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  • COMPARISON OF STRENGTH

    TRAINING PROGRAMS ON SPRINT

    TIME PERFORMANCE

    A Thesis Presented

    to the

    Graduate Faculty of Health and Physical Education

    Eastern New Mexico University

    In Partial Fulfillment of the Requirement for the Degree

    Master of Science

    by

    Tracie L. Edwards

    April 4, 2012

  • ii

  • iii

    COMPARISON OF STRENGTH TRAINING PROGRAMS ON SPRINT

    TIME PERFORMANCE

    Abstract of a Thesis

    Presented to the Graduate Faculty of Health and Physical Education

    Eastern New Mexico University

    In Partial Fulfillment of the Requirements

    for the Degree Master of Science

    by Tracie L. Edwards

    April 4, 2012

  • iv

    Abstract

    Different training methods are used to improve force, muscular strength, and power.

    One method is high-resistance (HR), which uses free weights or plate loaded machines.

    Another training protocol is high-velocity (HV), training which utilizes light loads and high

    repetitions along with plyometric exercises to increase speed and velocity. HV training is

    thought to improve overall sprint time performance whereas HR training will improve the

    initial acceleration phase of the 100 m sprint. The purpose of this study was to examine the

    effects of both HV and HR training programs on overall sprint time performance in female

    high school students. This study included 30 females from Roswell, New Mexico, ranging in

    age from 14 to 18 years. The participants, who were not familiar with strength training

    programs, were selected from the physical education classes at local high schools. For 8

    weeks the students participated in either a HV (jumping, bounding, hopping, etc.) or HR

    (squat, hamstring curls, leg press, leg extension, etc.) training protocol. Both training groups

    improved the 100 m sprint time from the pre-test to the post-test over the training period,

    however, the results showed no significant difference between the two groups mean change

    scores on sprint times (F(1, 28) = 0.062, p > 0.05). Follow-up analysis showed the within-

    subjects results were statistically significant (F(1, 28) = 18.687, p < 0.001) indicating that the

    8 weeks of training induced a significant change for individual sprint time performance

    regardless of protocol.

  • v

    Acknowledgements

    I want to first thank God for giving me the strength and guidance to finish what I

    started. I want to thank my husband for all of his support and allowing me to pursue my

    dream of getting a masters degree. I also want to thank my family who lives so far away in

    South Texas for giving me the confidence to complete this study and to look forward to the

    future.

    I want to thank Dr. Sarah Wall for all of her time and effort in guiding me through the

    tumultuous task of completing this study. She showed me the how to prepare for any future

    tasks that I may encounter along with encouraging me to finish what I started. I would also

    like to thank Dr. Mary Drabbs and Dr. Matt Martin for taking the time to be part of my thesis

    committee.

    I would like to thank the faculty and staff members at Roswell High School; P. J.

    Garnett, Micah Trujillo, Monika Trujillo, and Michael Garcia; and Valley Christian

    Academy; Tim Fuller, and Zach Ryan; for letting me into their physical education classes

    and campuses. Lastly, I would like to thank the participants of the study who gave their time

    and effort to me during the study.

  • vi

    Table of Contents

    Page

    Abstract iii

    Acknowledgements v

    List of Tables viii

    Chapter

    I. Introduction 1

    Problem Statement 3

    Purpose Statement 3

    Research Hypothesis 3

    Operational Definitions 3

    Limitations 4

    Assumptions 4

    Delimitations 4

    Risk and Benefits 5

    Significance of the Study 5

    II. Review of Literature

    Predicting Sprint Speed Based on Strength and Power 6

    Effects of Specific Types of Training on Running Form 9

    Strength Training For Adolescents 12

    Training Method Effects on Sprint Time Performance 14

    Summary 18

    III. Methods

    Introduction 20

    Participants 20

    Setting 20

    Research Design 21

    Instruments 21

    Validity of Study 21

  • vii

    Procedures 22

    Analysis Method 25

    Summary 25

    IV. Results

    Introduction 26

    Descriptive Statistics 26

    Data Treatment 27

    Statistical Analysis 27

    Summary 28

    V. Discussion

    Introduction 29

    Hypothesis Findings 29

    Pre- and Post-test Comparisons 31

    Conclusions 33

    Considerations for Future Research 33

    References 36

    Appendices 39

  • viii

    List of Tables

    Table Page

    1. Mean Performance Times of Female Physical Education Students 26

  • 1

    CHAPTER I

    Introduction

    An optimal level of strength, power, and force are necessary to maximize sprinting

    performance because sprinting requires a powerful start and a strong finish. Strength training

    when used as a form of physical conditioning can increase force, muscular strength and

    power. Methods such as high-resistance (HR) training have been used to increase velocity

    where sprint running and overall dynamic performance are involved (Delecluse et al., 1995).

    For example, HR training involves heavy loads with few repetitions and is designed to

    increase strength and power. A second popular method, termed high-velocity training (HV),

    involves light loads and high repetitions to increase speed and velocity. Other training

    methods using parachutes, sleds, weight belts and vests to improve explosiveness, quick

    acceleration, and first-step quickness have been studied to find the change in running

    kinematics and to determine if an increase in power is obtained (Cronin, Hansen, Kawamori,

    & McNair, 2008). A variety of training programs have been studied to determine which

    method of training works best for improving sprint time and phase performance (Delecluse et

    al.). Resistance training in combination with speed and HV training methods have also been

    used to determine the effects of such training on different age groups; however, little research

    includes adolescent females as the particpants.

    In 2007, Ignjatovic, Radovanovic, and Stankovic investigated how different

    resistance training programs affected muscular strength among children and male

    adolescents. Also, Blazevich and Jenkins (2002) studied male elite junior sprinters to

    determine the effects of high- and low-velocity resistance training on sprint running

    performance and strength performance. Many studies have also been completed on children

  • 2

    and other sport-specific athletes to determine the ratio of strength and power needed to

    achieve maximal running speed and which training programs improve sprint performance

    (Faigenbaum et al., 2007). These studies provide insight for strength and conditioning

    coaches to improve not only the entire sprint performance for different age groups, but also

    different phases of the sprint.

    The sprint has three phases: the initial acceleration, maximum running speed, and

    speed endurance (maintenance). In track and field, a sprinter may possess a good start but

    lack the ability to maintain maximum speed. The initial acceleration phase occurs between

    the start and 10 meters (m). The maximum running speed is achieved among untrained

    sprinters between 10 m and 60 m, but it may take an elite sprinter 80 m to reach top speed

    due to a higher endurance capacity (Delecluse et al., 1995). The endurance phase is the last

    10 to 20 m of the sprint. In addition, training for the initial acceleration phase is different

    than training for maximum running speed (Delecluse et al.). Researchers have studied the

    impact of resistance training emphasizing the exact methods which improved the athletes

    time in each phase (Young, 2006). Some researchers suggest that the benefit of improved

    sprint time is gained from HR training (Delecluse et al.), but it has yet to be shown that a

    sprinter can improve his/her speed when the HR training is performed at higher movement

    velocities (Blazevich & Jenkins, 2002). In addition to resistance training, many athletes use

    other training components, such as speed and agility exercises to enhance the athletic

    performance, but Blazevich and Jenkins hypothesized that if athletes wish to improve their

    HV force production, resistance training exercises should be performed at high movement

    speeds.

  • 3

    Coaches and athletes are always looking for better training methods to improve an

    athletes performance, but to date few studies have shown that HR training improves overall

    sprint time performance. In addition, given the number of studies on training programs with

    junior and elite male athletes along with male adolescents, more information is needed for

    coaches of female students at the high school level.

    Problem Statement

    The problem was that little information existed about the effect of different training

    programs on sprint running performance in high school female students.

    Purpose of the Study

    The purpose of this study was to examine the effects of both high-velocity (HV) and

    high-resistance (HR) training programs on overall sprint time performance in female high

    school students.

    Research Hypothesis

    The hypothesis of this study was that HV training would result in a greater

    improvement in sprint time when compared to HR training for high school female students.

    Operational Definitions

    Power is the amount of work done per unit of time and is the product of force and

    velocity. P = Fv.

    One repetition maximum (1RM) is the most amount of weight that a participant can

    lift for one repetition but not two.

    High-resistance training (HR) uses heavy weights with movement performed at a safe

    speed and fewer repetitions to increase maximum strength.

  • 4

    High-velocity training (HV) uses the athletes body weight as the resistance where

    coordination and speed are emphasized during the movements. Exercises include

    jumps, skipping, ladder drills, bounding, and hopping.

    Plyometric training is a technique used to develop explosive strength and power, and

    consists of a quick eccentric stretch followed by a powerful concentric contraction.

    Limitations

    Limitations of this study include:

    1. students may not be able to attend all of the training sessions;

    2. extra training may be performed outside the required training sessions;

    3. the study may be affected by injuries while training or dropout due to illness;

    4. the students may not be motivated to perform the training or tests as specified by

    the researcher;

    5. the participants are part of a convenience sample from intact physical education

    classes.

    Assumptions

    Assumptions of the study are:

    1. students will attend all training sessions;

    2. extra training will not be performed outside the required sessions;

    3. test participants will follow the testing protocols of the study;

    4. test participants will give maximal effort during all training and testing sessions.

    Delimitations Delimitations of the study are:

  • 5

    1. only female students between the ages of 14 and 18 years from the Roswell area

    of New Mexico participated in the study;

    2. the study was performed for eight weeks during the academic school year;

    3. the testing was done outside on an all-weather rubberized track;

    4. no one who had, or developed, chronic muscle pain or injury was included in the

    data analysis;

    5. sprint testing only took place on days without extreme weather conditions.

    Risk/Benefits

    A risk of the study was that any student might have become injured during the

    interventions. However, this risk was no greater than that occurring during everyday

    practices and/or activities during the physical education class. One potential benefit of the

    study for the participants was a decreased sprint time. Another benefit included knowledge of

    strength training methods for coaches/teachers to utilize a program that might be more

    effective in improving sprinting performance.

    Significance of the Study

    The significance of this study was to potentially inform physical educators of

    effective training methods to improve the physical well being as well as performance of their

    students. The results of the study could influence students to achieve new levels in their

    overall physical performance and help physical education teachers by using these techniques

    to teach students how to improve their overall performance. This study will also contribute to

    the existing literature about effective training methods to increase sprint performance.

  • 6

    CHAPTER II

    Review of Literature

    The purpose of this study was to examine the effects of both high-velocity (HV) and

    high-resistance (HR) training programs on overall sprint time performance in female high

    school students. Sections included in this review of literature are predicting sprint speed

    based on strength and power, effects of specific types of training on running form, strength

    training for adolescents, training method effects on sprint time performance, and summary.

    Predicting Sprint Speed Based on Strength and Power

    It is assumed that more powerful athletes have faster sprint performance outcomes.

    Researchers have found mixed results, however, when predicting sprint speed based on

    strength and power measures (Cronin & Hansen, 2005; Smirniotou et al., 2008). Also, Baker

    and Nance (1999) studied various measures of strength and power on sprinting capability.

    Timed 10 m and 40 m sprints for 20 professional male rugby players were conducted over a

    week at the completion of preseason training. The distances of 10 m and 40 m are

    comparable to the distance during play in the sport of rugby and many other sporting events

    and are thought to be indicative of the initial acceleration and maximum sprinting speed

    capability of athletes. The participants involved in the study had previously participated in a

    resistance and sprint training program for a minimum of four years which allowed for some

    familiarity with the resistance exercises that would be performed. On the first day of testing,

    the participants completed a three repetition maximum (3 RM) test by performing full squats

    and power cleans to measure strength. On the second day of testing, the participants

    completed a timed sprint test over 10 m and 40 m along with a loaded barbell jump squat test

    for maximal power. During the barbell jump squat test, the athletes performed three

  • 7

    consecutive plyometric movements against loads ranging from 40 kg to 100 kg to test for

    power. Even though the researchers tested measures of strength and power, the results of this

    study showed that none of the exercises performed were significantly correlated to

    performance in the 40 m sprint. However, strength and power exhibited a much stronger

    relationship when compared to the 10 m sprint time (Baker & Nance). The researchers

    concluded that there may need to be separate training strategies to improve running speed

    over the two distances for game play. This study also showed that specificity of training may

    be of more use than training for the sport as a whole when trying to increase speed over

    specific distances.

    To determine which protocol works best, different distances have been used to

    compare training methods for various sport programs. The distances typically used are

    similar to those for plays within sports like football, soccer, rugby, baseball, and softball;

    however, no distance less than 100 m exists in the sport of outdoor track and field. Therefore,

    in the following study, the researchers used short distances to try and explain the amount of

    power a track and field athlete exerts during the start of a race. Young, McLean, and Ardagna

    (1995) examined the relationship between strength qualities and sprinting performance.

    Eleven male and nine female sprinters, hurdlers, and jumpers between the ages of 16 and 18

    years participated in the study. An electronic timer was used to determine the sprint times at

    2.5, 5, 10, 20, 30, 40, and 50 m along with two force platforms to record the horizontal and

    vertical reaction forces during the sprint start. The force platforms used during the sprint test

    measured the block time, resultant block velocity, resultant block acceleration, and maximum

    resultant block force and were placed under both the hands and feet during the block start.

    The subjects performed two maximum effort timed 50 m sprints from a block start, and the

  • 8

    fastest time was used for the data analysis. After the sprint tests were performed, power tests

    consisting of squat jumps, counter movement jumps, and platform jumps for maximum

    height were then conducted. The counter movement jumps involved execution of a dip

    immediately prior to the upward phase of the jump takeoff. Participants in the study also

    completed a jump test from a 120 knee angle with a 19 kg bar resting on the shoulders. This

    knee angle is reported to be within the range to produce maximum force for the knee

    extensors and the angle is similar to the knee angle of the rear leg in the set position of the

    block start (Blount, Hoskinsson, & Korchemny, 1991). Results of the Young and colleagues

    study showed strength qualities, or power, were related to sprinting performance at both the

    start of the sprint and at maximum speed. (Note: the distance at which maximum speed is

    obtained differs among researchers and sprinters; therefore different distances are used in

    studies). Young and colleagues also found that the three best predictors of starting

    performance were obtained during the concentric jumping test, counter movement jump test,

    and drop jump test, whereas the single best predictor of maximum sprinting speed was the

    force generated within the first 100 ms from the initiation of movement out of the blocks.

    The previous studies indicated that specific strength training movements, like counter

    movement jumps, can predict the overall performance of the athlete; however, these training

    methods may affect running mechanics (Cronin et al., 2008). Strength measures, such as ones

    used by Young et al. (1995), may allow for enhancement of training programs and help

    coaches predict how fast their athletes may be. This knowledge should allow coaches to

    place athletes in the correct positions or events that relate to the sport in which they are

    participating. Research is still being performed to determine which strength training

    protocols work best.

  • 9

    Effects of Specific Types of Training on Running Form

    Sprint running is described in three phases: an acceleration phase, a maximum speed

    phase, and a maintenance phase (Delecluse et al., 1995; Moir, Sanders, Button, & Glaister,

    2007). The ability to develop maximal sprint speed in a short time may be of greatest

    significance when sprint efforts are of short duration. The athletes ability to accelerate is

    dependent on factors such as running technique (kinematics) and the force production of the

    lower limb musculature (Cronin et al., 2008). Understanding the athletes abilities allows

    coaches to design training exercises that use applied forces as resistance to improve force

    production while running different distances. Coaches and athletes use weighted vests, sleds,

    parachutes, tires and bungee cords regularly to improve leg strength and force production;

    however, the use of these objects may change sprint kinematics (Cronin, Ogden, Lawton, &

    Brughelli, 2007).

    In 2007, Cronin and his colleagues enlisted the help of 20 athletes involved in

    competitive sports to determine what effect weighted vests and sleds had on trunk lean and

    foot strike. The participants were videotaped while running a 30 m sprint from a standing

    start with cameras placed at 5 m, 15 m, and 25 m from the start to provide a baseline measure

    of sprint kinematics. The subjects were also videotaped while wearing a weighted vest and

    pulling a sled performing the same 30 m sprint. Loads of 15% and 20% of body mass were

    chosen to examine the effect of heavier external loads on sprint kinematics. The sleds base

    (7.2 kg) was attached to the athlete using a shoulder harness and a 2 m long rope. The vest

    consisted of a belt around the athletes waist with straps over the shoulders that were fastened

    at the back so the load could be added evenly around the front and side of the waist. Dual

    beam infrared lights connected to an electronic timer were placed at the start, 10 m, and 30 m

  • 10

    marks to measure sprint times during all trials including the un-resisted, sled towing, and vest

    wearing trials. The results of this study showed that the 30 m sprint times increased as the

    load of both sled and vest increased along with a step count increase through the acceleration

    phase of sprinting. The greatest influence on performance was found when towing a sled was

    compared with sprinting with a weighted vest. The results reflect the different manner in

    which the two techniques overload the body and therefore provide insight into possible

    different mechanisms by which vest and sled towing may act to improve sprint acceleration

    performance. The researchers also found that sled towing and vest sprinting both resulted in

    acute changes in sprint kinematics during the acceleration phase. Cronin and colleagues

    (2008) believed that sled towing may be a more appropriate training modality for the early

    stages of the acceleration phase of sprinting because the running mechanics are similar to that

    of normal block starts.

    Sleds and weighted vests are common pieces of training equipment that many schools

    can provide to train their athletes without putting them in the weight room (Cronin et al.,

    2007). Bungee cords, tire pulling, and parachutes are also used to help athletes gain strength

    and improve performance by using resistance other than weights. These methods may be

    effective for improving strength but also can cause a change in the athletes kinematics while

    running by changing the angle of foot strike and trunk lean (Cronin et al., 2007). If coached

    properly, the athlete can use these techniques during the initial acceleration phase; however,

    the running mechanics are not the same throughout the rest of the sprint performance. In

    2008, Alcaraz, Palao, Elvira, and Linthorne conducted a study on 11 male and seven female

    sprinters and jumpers between the ages of 17 and 26 years to compare kinematics of

    sprinting at maximum velocities without resistance to the kinematics of sprinting when using

  • 11

    three types of resisted sprint training devices (i.e., sled, parachute, and weight belt). The

    weighted sled was attached to the participant at the waist and was loaded with 16% of the

    participants body mass. A medium sized parachute (1.2 m x 1.2 m) was also used and was

    attached to the participant at the waist by a harness. Lastly, a weighted belt was loaded to 9%

    of the participants body mass and placed around their waist. The participants were given a

    20 m run-in start to the actual trial distance of 30 m. This distance allowed the participants to

    be at top running speed during each weighted trial. The researchers found that the sled,

    weighted belt, and weighted vest were appropriate devices for training the maximum velocity

    phase in sprinting, even though an acute reduction in stride length and running velocity

    occurred. The parachute and sled produced the greatest kinematic change in the lower limbs

    and trunk causing the trunk to lean more and the participant to have a shorter foot strike

    distance. The researchers indicated that this is an adequate form of resistance training due to

    the improved sprint time; however, the trunk lean must be carefully monitored with resisted

    sprint devices so that an inappropriate angle is not induced or reinforced (Alcaraz et al.).

    When compared to Cronin et al. (2008) the studies had similar findings which suggest that

    training with sleds and weighted vest are beneficial for improving sprint time, but the athletes

    need to be monitored and corrected when their running mechanics change.

    Training with resistance devices is a common program in many coaches regimens.

    Coaches should use them appropriately so the athlete experiences a large training stimulus

    which stresses the system to produce adaptation to improve overall physical performance.

    Coaches should guard against specific changes in the athletes forward lean and changes in

    the angles for the support leg during the foot strike (Alcaraz et al., 2008).

  • 12

    Strength Training for Adolescents

    Researchers have used different combinations of sets and repetitions to study the

    effects of resistance training on young athletes (Faigenbaum, Milliken, Moulton, & Westcott,

    2005). Faigenbaum (2000) described adolescence as a period of time between childhood and

    adulthood and includes girls between the ages of 12 and 18 years and boys aged 14 to 18

    years. Training athletes in this age group has not been as extensively studied as training

    adults, and many questions and concerns arise when training younger athletes that include

    whether or not strength training can increase muscular strength in young athletes and the

    perceived high risk of injury (Guy & Micheli, 2001). The role of strength training for

    adolescents remains a topic of controversy due to misconceptions regarding the risks to

    younger athletes, such as a loss of flexibility and range of motion necessary for optimal

    performance in their chosen sport (Guy & Micheli). However, researchers have found

    benefits that refute the misconceptions, for example that strength training can increase

    flexibility and range of motion among children (Faigenbaum et al., 2005; Guy & Micheli).

    It appears, however, that recommended training protocols for maximizing muscular

    strength in adults (i.e., heavy weight combined with low repetitions) might not be ideal for

    adolescents who could benefit from performing additional repetitions with a lighter load

    during the early phase of training (Faigenbaum et al., 2005). For example, Faigenbaum and

    colleagues (2005) studied the efficacy of pre-adolescent children 8 to 12 years old

    performing lighter loads for 15 to 20 repetitions for eight weeks. The results indicated that

    higher repetitions resulted in greater gains in local muscular endurance and flexibility among

    children. However, in a later study conducted on pubertal boys, training with lower

    repetitions resulted in greater gains in local muscular endurance (Faigenbaum et al., 2007).

  • 13

    Guy and Micheli (2001) believed that resistance training can result in marked strength gains

    in the prepubescent child which is helpful due to the increase in sports participation among

    younger athletes.

    Competitive sports have increased in popularity among prepubescent children and

    raise many questions about the risk associated with weight training for those desired sports.

    Injuries are common in any activity and can be avoided in many cases; however, many

    injuries that occur during youth training are attributed to improper lifting technique and

    excessive loading (Guy & Micheli, 2001). Guy and Micheli believed that a better assessment

    of the risk associated with resistance training would come from studies of closely monitored

    and supervised training programs with properly prescribed training loads. Their conclusion

    was that the risks associated with resistance training are no greater than those of competitive

    sports given that the strength training program is properly supervised and the athletes are

    instructed correctly.

    Free weights, weight machines, and exercises that use the bodys own resistance are

    different types of training that are used while strength training young athletes. Ignjatovic and

    colleagues (2007) examined the effects of strength training on young athletes for eight

    weeks. Twenty-one basketball players ranging in age from 14 to 15 years participated in a

    training protocol of three circuits of six repetitions for each of the different exercises

    performed (but not listed in the study) for the lower back muscles, upper and lower body, and

    abdominals. In the first three weeks of training, two sessions per week were performed and

    during weeks three through six the number of training sessions increased to three. During the

    last two weeks of training, the sessions decreased to two per week. The researchers used

    isometric muscle strength tests (dynamometer and Standing Leg/Sitting Calf Muscle

  • 14

    Extension) that registered maximal voluntary contraction force. A video camera and motion

    analysis software were used to determine the height the participants produced during

    maximal vertical jump. The researchers found that applied training for strength development

    led to an increase in maximal isometric force along with an increase in concentric force

    produced in leg extensions and calf extensions. Ignjatovic et al. concluded that strength

    training in young athletes resulted in an increase in maximal isometric muscle contraction

    and increased performance of the vertical jump of the participants.

    Adolescent participation in strength training programs can be appropriate when the

    programs are designed well and competently supervised. Strength training not only provides

    improvement in sport performance but may provide the adolescents with a gain in self-

    confidence in their physical abilities so they will continue to participate in other activities as

    they get older (Ignjatovic et al., 2007).

    Training Method Effects on Sprint Time Performance

    Strength training has become a popular way for athletes to increase overall

    performance in sports. Many types of strength training methods are used by strength and

    conditioning coaches and athletes to increase speed, strength, and power. One popular

    method of weight training which requires athletes to lift heavy loads with few repetitions is

    called high-resistance (HR) (Delecluse et al., 1995). A second popular training technique is

    high-velocity (HV) training which can include plyometric exercises. Plyometric exercises use

    the athletes body weight as the resistance and include exercises such as bounding, hopping,

    skipping, and jumping. Some coaches and athletes perceive plyometric training as the only

    strength-training method to result in an improvement in sprint performance because

    coordination and speed are specifically related (Delecluse et al.).

  • 15

    Delecluse and colleagues (1995) found that training with heavy weights and low

    repetitions allowed the participants to increase sprint speed over short distances; however, a

    study performed by Faigenbaum et al. (2007) researched the effects of plyometric exercises

    added to resistance training in early pubertal boys to determine which program was more

    beneficial in improving strength and sprint times. Faigenbaum et al. (2007) hypothesized that

    six weeks of training the early pubertal boys with a combined resistance and plyometric

    training program would lead to greater improvements in fitness performance. Twenty-seven

    boys between the ages of 12 and 15 years were randomly placed in a resistance training (RT)

    group and a combined resistance and plyometric training (PRT) groups. Prior to the start of

    the study, the subjects were tested in a 9.1 m shuttle run, vertical jump, long jump, and seated

    medicine ball toss. Both groups then exercised twice a week for six weeks. The PRT boys

    participated in a plyometric training program that included jumping forward and backward,

    one and two leg hops, hurdle and cone hops, and dot drills. The PRT then joined the RT

    participants and performed additional resistance training of three sets of ten to twelve

    repetitions in the squat, front squat, and upper body resistance exercises. These exercises

    were to be performed in an explosive manner to emphasize maximum performance during

    the remainder of the training protocol. The RT group did not participate in plyometric

    exercises during this training intervention. At the end of the 6-week training program the

    participants' strength and speed were reevaluated using the vertical jump, long jump, seated

    medicine ball toss, and 9.1 m shuttle run test. The results found that while strength increased

    neither training program improved sprint performance. This was possibly due to the short

    sprint distance which did not allow the participants to reach maximum running velocity.

  • 16

    Improving the final sprint time performance is a goal of both coaches and athletes. As

    previously mentioned, the sprint consists of several components such as the initial

    acceleration, and maximum speed, and maintenance phases (Delecluse et al., 1995, Moir et

    al., 2007). All three phases must be performed at a high level to maximize sprint time, and

    each phase requires different physical abilities for optimal sprint performance. Understanding

    the effect of resistance training on separate sprint phases is important when trying to explain

    how the strength gained may or may not have improved sprint performance. Moir et al.

    enlisted 16 male participants between the ages of 17 and 21 years who were physically active

    in sports including rugby, soccer, and basketball to participate in the study. Prior to the start

    of the training protocol, the researchers timed the participants in a 20 m sprint. During an 8-

    week resistance training program, two mesocycles, each four weeks in length, were used.

    The first mesocycle emphasized a strength-endurance program consisting of exercises such

    as parallel squats, bench press, and power cleans which the participants performed for three

    sets of 12 repetitions. The second mesocycle emphasized the development of maximum

    strength, also a 4-week program, which consisted of three sets of five repetitions. Although

    the researchers listed no justification for the order of their prescribed mesocycles it does

    appear to represent principles of periodization training, which is when training is varied in

    intensity, type, and length of time. At the end of the 8-week study, sprint times were tested

    again over 20 m measuring the initial acceleration phase of the sprint. During this study Moir

    and collogues found increased maximum and explosive strength while also increasing

    accelerative sprint time immediately after the training period. The study also concluded that

    potential benefits of increased muscular strength during sprints less than 30 m are likely to be

    affected by the running technique of the participant (Moir et al.).

  • 17

    Many different training programs are used to improve sprint time along with overall

    athletic performance; however, coaches are free to choose which one works best for their

    program. In 1995, Delecluse and colleagues compared the effects of HR and HV training on

    sprint performance. The researchers believed that HR training results in improved initial

    sprint acceleration without improving maximum speed whereas HV training, that includes

    movement specific plyometric exercises, would improve maximum running speed. The male

    physical education students included in the study had not taken part in an earlier strength

    training program. Sixty-six students between the ages of 18 and 22 years were randomly

    placed into four groups including HR, HV, run, and passive groups. Prior to the start of the

    study, all participants performed a pre-test in the 100 m, along with being tested for their

    10 RM strength for bench press, leg press, half squat, leg extension, and arm curl. In

    addition, the HV group was given a pre-test for bounding, hopping, the standing broad jump,

    and vertical jump to determine their maximum distances prior to the training period. These

    pre-tests allowed the participants to familiarize themselves with the exercises that were

    included in the training program. The run group participated in a running workout (not

    explained) with the other two training groups once a week to see if the running program

    alone would elicit a change in sprint times, while the passive group did not train at all. The

    intervention took place over the course of nine weeks. The results found by Delecluse et al.

    showed that HR training increased the participants strength levels, but the effect on sprint

    performance was only significant when compared to the passive training group. In addition,

    the results showed that training with an increasing load in this condition resulted in greater

    initial sprint acceleration but no significant improvement for other components or parameters

    of sprint performance such as continued acceleration and maintaining maximum speed. On

  • 18

    the other hand, the HV group was the only group to significantly improve in the 100 m time

    due to a gain in initial acceleration. Also, when compared to the HR group, the HV group

    was more efficient in improving initial acceleration and final sprint time.

    The studies discussed found that different training protocols improved overall

    performance when used together but also found that specific training protocol improved

    certain phases of the sprint, not the overall sprint performance. However, Faigenbaum and

    colleagues (2007) showed that in order to improve the sprint performance as a whole the

    training protocol of HR and HV should be used together.

    Summary

    Specific strength and power measures can predict the speed of athletes over short

    distances such as the initial acceleration and maximum speed phases of the 100 m sprint. The

    training methods used to achieve power and strength output can also hinder the athletes

    performance by changing foot strike angles or trunk lean. These effects can cause an increase

    in time and injury if not properly supervised by trained staff during practices. Different

    training methods have also been studied to determine which works best among elite male

    athletes and boys of various ages; however, few studies relate to adolescent females.

    Previous studies have shown that training programs containing HV exercises improve sprint

    time performance among males and younger athletes which will help coaches and athletes

    improve performance and conduct proper training programs. The findings of the studies on

    how training programs can improve specific phases were consistent, but researchers believed

    that the programs should be used together to improve the sprint performance, and that

    training helps adolescents improve self-esteem as well as strength and power. More research

  • 19

    should to be conducted to look at training programs among females as well as males to help

    achieve athletic success.

  • 20

    CHAPTER III

    Methods

    Introduction

    The purpose of this study was to examine the effects of both high-velocity (HV) and

    high-resistance (HR) training programs on overall sprint time performance in female high

    school students. Pre- and post-test 100 m sprint times were analyzed to understand the effects

    of HR training and HV training on 100 m sprint times among female students. Sections

    included in this chapter are participants, setting, research design, instruments, validity of

    study, procedures, analysis method, and summary.

    Participants

    In this study 30 females from Roswell, New Mexico, ranging in age from 14 to 18

    years, were selected from a volunteer pool of students in the physical education classes at

    Roswell High School and Valley Christian Academy. The participants who were familiar

    with strength training programs were excluded from the analysis as this might have adversely

    affected the results. However, these adolescents were able to participate alongside their peers

    in the activities.

    Setting

    Training was conducted in the Roswell High School and Valley Christian Academy

    weight rooms with similar facilities and training machines. Testing was conducted outdoors

    on the track facilities on the Roswell High School campus. An athletic trainer was present at

    the time of training and testing to provide drinking water and see to any medical needs during

    the interventions. Testing did not occur on days when the wind speed exceeded 15 mph,

    during rain, or on days when the temperature was below 65 F or above 90 F.

  • 21

    Research Design

    A quasi-experimental design was implemented. Due to the real-world setting, pre-test

    and post-test groups were created using matched pairs while as many threats to validity as

    possible were controlled. This design was used to analyze the mean change in sprint times at

    the end of the 8-week intervention to determine if the training programs had any effect on the

    participants times. The training protocol was the independent variable, and the change in

    sprint time performance was the dependent variable.

    Instruments

    Sprint speed was assessed using an electronic timing system manufactured by Equine

    Electronics, which measured time within 1/100th of a second. The electronic timing device

    sent a signal upon the release of pressure on the sensor pad to the handheld timing device.

    The device shut off once the participant broke the laser barrier. The electronic timing device

    was deemed acceptable for this study, but the timing equipment had unknown validity and

    reliability. The equipment was pilot tested to determine the feasibility of the testing

    equipment. The resistance training equipment that was used included a 45 lb weight bar,

    Smith squat machine, hamstring curl, hip extension and flexion on a weighted cable

    machine, weighted seated leg press, and seated leg extension. Cones were also utilized during

    the plyometric exercises

    The sprint testing procedure had face validity because the 100 m sprint is an actual

    race in track and field events.

    Validity of Study

    Possible threats to internal validity of this study were history, selection bias, and

    expectancy. History was a threat due to any events occurring during the experiment that were

  • 22

    not part of the treatment such as any extra training performed by the participants. The

    convenience sample that was used was a threat to internal validity; selection bias affects the

    ability to generalize as the location the participants were drawn from was not a full

    representation of the female student population. Also, the fact that the researcher expected

    that one training program would enhance the participants sprint time in the 100 m was a

    threat to validity.

    Procedures

    Human subjects approval was obtained prior to the start of the study. After additional

    approval to conduct the study had been granted by the Roswell High School and Valley

    Christian Academy principals, and coaches/physical education instructors, a meeting was

    held to discuss and explain the study to parents and potential volunteers. During the meeting,

    the researcher asked the volunteers about their current knowledge and experience with

    strength training programs. This knowledge allowed the researcher to determine potential

    participants for the training intervention. The researcher also described the types of exercises

    that would be performed during the HR training program (i.e., leg press, leg extension, hip

    extension, hip flexion, hamstring curl, calf raise, and squat) and the HV training program

    (i.e., standing broad jumps, vertical jumps, cone jumps, skipping, bounding, and hopping).

    All participants and their parent/guardian signed informed consent forms (Appendix A) that

    were handed to the researcher before approval to join the study was given.

    Before the two 100 m trials performed during the pre-test took place, the participants

    were notified of which day they would be needed based on alphabetical order. Based on the

    number of participants from each class period, the girls were divided into groups with a

    maximum of 10. The entire pre-trial took place over two days to provide ample time for

  • 23

    completion of both trials and not allow for too much rest (i.e., cool down) between each trial.

    For the pre-test and the post-test, the participants met at the Roswell High School track

    facility wearing shorts, t-shirt, possibly sweatpants and sweatshirt, and flat soled running

    shoes (spiked shoes were not allowed).

    The electronic timing equipment was set up using a single lane on the track. The

    100 m start and finish line were already marked on the track, and the pressure switch was

    placed at the starting line. The participants were shown how to start the square shaped

    pressure switch, the correct starting stance (three-point stance) and the proper technique to

    correctly finish the sprint. The participants were allowed to practice starting the electronic

    timing device and jogging through the infrared beam from a short distance of 20 m; once all

    10 participants felt comfortable, the warm up activities began.

    The participants were led through a warm up by the researcher that consisted of a 400

    m jog followed by static and dynamic stretches including bounding exercises. Following the

    stretching, the individuals were allowed any additional warm-up activities they felt necessary

    before performing the 100 m sprint. At the conclusion of the warm up activities the

    researcher moved the infrared beam, which stopped the timer, to the finish line. Each

    participant ran individually starting from a three point stance. No starting blocks were used to

    avoid any familiarity with previously used equipment. Starting commands were similar to

    those used in competition, such as on your mark, set, and go. Each participant was

    individually assigned a subject identification number to keep track of the results and time in

    the 100 m. Each participant completed two timed trials with a maximum 15 minute rest

    period between each trial. The participants time was displayed on a digital hand held reader

  • 24

    held by the researcher at the finish line and the time was manually recorded with the best

    time for each participant being used in the data analysis.

    At the conclusion of all pre-test trials, the sprint times were ranked from the fastest to

    the slowest time and participants were assigned to one of the two intervention groups, HR

    and HV, by way of matched pairs. The first two participants with the fastest times were

    placed in different training groups, then the next two participants were randomly assigned to

    the groups and so on until all participants were assigned.

    After the pre-test in the 100 m dash was completed, the participants who were placed

    in the HR training group engaged in a strength test to find their 8 repetition maximum (8

    RM) in each of the selected weight training exercises including leg press, leg extension, hip

    extension, hip flexion, hamstring curl, calf raise, and Smith machine squat. This test was

    performed over several days within the week following the 100 m pre-test. The results of the

    8 RM tests were recorded for later use when the training sessions began.

    For the next eight weeks the participants engaged in their respective training

    programs. For the first two weeks, training took place twice a week following which the

    training increased to three days a week. The HR group was directed to perform the exercises

    in a controlled manner and to execute them safely on the exercise machines. The participants

    were directed to lift three sets of their 8 RM. The HR training program exercises are outlined

    in Appendix B. Because adaptation to the weight training was expected, the researcher added

    weight as required to maintain the 8 RM as the student got stronger.

    The HV group participated in a program of unloaded plyometric and agility exercises

    that emphasized the speed of movement. Unloaded plyometric exercises use the body and

    gravity as resistance while performing the exercises. This program also involved frequency

  • 25

    drills including standing broad jumps, vertical jumps, cone jumps, skipping, bounding, and

    hopping as outlined in Appendix C. A circuit involving the exercises was performed three or

    four times in succession.

    A post-test for sprint time was performed in a similar manner to the pre-test at the

    conclusion of the 8-week intervention using the same timing device. At the end of the

    training and research period, the mean change in 100 m time was calculated for each

    participant (Appendix D).

    Analysis Method

    Data analysis was done using a paired t-test to examine whether a difference existed

    between the two groups mean change scores. The null hypothesis was that the HV training

    would not result in a greater improvement in sprint time when compared to HR training for

    high school female students. Alpha was set at .05 to control for type I errors.

    Summary

    Research has been performed using males of different ages and abilities to test

    different training methods to improve performance, but there is a lack of research relating to

    both adolescent females and physical education students. Studies have also been conducted

    to see what effects different exercises and equipment have on specific phases of sprint

    running, but few look at the sprint as a whole. This study was designed to test the effects of

    HR and HV training on overall sprint time performance in the 100 m among female physical

    education students. Participants of this study may not only benefit from the training by

    achieving a faster sprint time, but may also improve their overall physical performance on

    state mandated assessments.

  • 26

    CHAPTER IV

    Results

    Introduction

    The purpose of this study was to examine the effects of both high-velocity (HV) and

    high-resistance (HR) training programs on overall sprint time performance in female high

    school students. Pre- and post-test 100 m sprint times were analyzed to understand the effects

    of HR training and HV training on sprint performance among female students. Sections

    included in this chapter are descriptive statistics, data treatment, statistical analysis, and

    summary.

    Descriptive Statistics

    Female participants were selected from a volunteer pool of students enrolled in

    physical education classes at Roswell High School and Valley Christian Academy High

    School. Participants (N = 30) ages 14-17 years were assigned to two groups - the HV group

    (n = 16) and the HR group (n = 14) - using matched pairs as described in Chapter 3.

    Table 1

    Mean 100 m Performance Times of Female Physical Education Students

    Age (years) Pre-test (s) Post-test (s) Change Score (s)

    M SD M SD M SD M SD

    HV 15.78 0.75 20.57 2.06 19.72 2.08 -0.85 1.10

    HR 15.32 0.40 20.04 1.89 19.18 1.53 -0.86 1.07

  • 27

    Data Treatment

    A between subjects design was implemented to analyze the mean change in sprint

    times at the end of the 8-week intervention to determine if the training programs had any

    effect on the participants times. All participants completed two trials of the 100 m during

    both the pre-test and the post-test and only the best trial time in each set was used for data

    analysis. The sprint times were measured using an electronic timing system, and all times

    were recorded to the 1/100th of a second. Preliminary review of the data suggested that

    training improved the 100 m sprint time regardless of the training protocol.

    The pre- to post-test change scores were computed for every participant and were

    used to calculate the mean for each group. A paired t-test was then used to calculate the mean

    change score for each group to determine if there were any significant improvements

    between the training protocols.

    Statistical Analysis

    Data were analyzed using SPSS Student Version 17 for Windows software to test

    the null hypothesis. The results showed no significant difference between the two groups

    mean change scores (F(1, 28) = 0.062, p > 0.05). Therefore, the null hypothesis, which stated

    that the HV training would not result in a greater improvement in sprint time when compared

    to HR training for high school female students, could not be rejected.

    Since an improvement was observed between the pre- and post-test time for both

    groups, further analysis was needed to confirm whether the improvement was significant. A

    repeated measures ANOVA was used to analyze pre- to post-test data for all individuals in

    both training groups over the eight weeks of training. The within subjects results were

    statistically significant (F(1, 28) = 18.687, p < 0.001) showing that the eight weeks of

  • 28

    training induced a significant improvement in the sprint time performance regardless of

    protocol.

    Summary

    Based on the results, no significant difference was found between the two training

    groups mean change scores. However, both protocols over the eight weeks of training

    resulted in a significant improvement in the pre- to post-test times for 100 m.

  • 29

    CHAPTER V

    Discussion

    Introduction

    The purpose of this study was to examine the effects of both high-velocity (HV) and

    high-resistance (HR) training programs on overall sprint time performance in female high

    school students. Participants for the study were 30 adolescent females (M = 15.56 years, SD

    = .65 years) who were participating in high school physical education classes at Roswell

    High School and Valley Christian Academy. The participants had little knowledge and

    experience with strength training and completed an 8-week training protocol consisting of

    HV exercises or HR exercises. The data were analyzed to determine which training protocol

    better improved sprint time performance in this population.

    This chapter discusses the results of the study and includes the following sections

    hypothesis findings, pre- and post-test comparisons, conclusions, and considerations for

    future research.

    Hypothesis Findings

    It was hypothesized that HV training would result in a greater improvement in sprint

    time compared to HR training for high school female students. Results showed that training

    improved overall sprint time performance in the 100 m dash; however, no significant

    difference between the mean change scores for the two training protocols (F(1, 28) = 0.062, p

    > 0.05) was found.

    According to current literature, a HV training program will improve sprint time

    performance in the 40 m and increase height during a vertical jump test (Chelly et al., 2010;

    Chimera, Swanik, Swanik, & Straub, 2004). Chelly et al. performed a series of exercises

    including counter movement jumps and squat jumps to assess the leg power of male soccer

  • 30

    players. For eight weeks the researchers had the participants complete the training during

    their regular season and found that plyometric training induced a significant increase in thigh

    muscle volume, a significant increase in squat jump and counter movement jump heights,

    and a significant increase in running velocities at 5 m and 40 m. Chimera et al. also evaluated

    the effects of plyometric training on the performance of the lower extremities during jumping

    exercises as well as the trainings influence on the stretch shortening cycle during running

    performance. The stretch shortening cycle is the stretching of the muscles before the

    contraction to produce a greater force during most jumping movements and is the basis for

    plyometric exercises. The researchers had 20 collegiate female athletes perform plyometric

    exercises twice a week for six weeks and found a significant increase in vertical jump height

    along with an improved sprint time. In the current study jump height was not measured, but

    the sprint time results are supported by the conclusions of Chelly et al. and Chimera et al.

    that running velocities among the participants may improve with plyometric exercises.

    Several earlier studies have also shown that a HV training program can improve

    sprint time in a 100 m sprint or a 40 yard shuttle run when compared to, or in combination

    with, a HR training program (Delecluse et al., 1995; Faigenbaum et al., 2007). Delecluse and

    colleagues analyzed the effects of training on 100 m sprint performance among male physical

    education volunteers between the ages of 18 and 22 years for nine weeks. The authors

    concluded that the HV group was the only training group to significantly improve the overall

    time in the 100 m sprint when compared to the other testing groups used in the study. Also,

    Faigenbaum and colleagues (2007) compared the effects of a 6-week training period of

    combined plyometric and resistance training and resistance training alone on fitness

    performance in boys between the ages of 12 and 15 years. The study found that combined

  • 31

    plyometric and resistance training significantly improved the vertical jump, long jump, and

    9.1 m shuttle run, whereas the resistance training only protocol did not show significant

    differences in the performance areas that were tested. This suggests that a combination of the

    two training programs will significantly improve sprint time performance. The previously

    discussed studies support the finding of the current study that the participants sprint time

    will be improved with plyometric training; however, the resistance training results seem

    contradictory. The current study produced a significant improvement in sprint time among all

    of the participants, possibly because the students were not very active before the study

    leaving room for an increase in performance. However, on several occasions a few students

    would not complete the required number of jumps. This may have affected the results among

    the HV training group when compared to the HR group.

    Unlike previous research, the results of the current study show an overall

    improvement in the participants sprint performance for both training protocols. This

    improvement may not have been significant between the two training groups but when

    comparing the pre- to post-test times, the change was significantly greater.

    Pre- and Post-test Comparisons

    The length of a training program (i.e., number of weeks) may help reduce injuries if a

    significant change could be shown in a shorter amount of time. Research indicates that a

    minimum of eight weeks is needed to see training adaptations in performance; however, the

    optimal amount of time required is likely to be greater than ten weeks (Kravitz, 1996;

    Randell, Cronin, Keogh, Gill, & Pedersen, 2011). The present study was conducted over the

    course of eight weeks so the pre-test trials could be performed during moderate temperatures

    and post-test trials concluded before the end of the school year in mid-May. The results of

  • 32

    the present study suggest that a training period of less than ten weeks may induce a

    significant change between the pre- and post-test sprint trials. The researcher acknowledges

    that both training protocols produced a significant improvement from the pre- to post-test

    trial sprint time, however, other outside factors may have influenced the outcome of the

    trials. The change in sprint time performance between the pre- and post-test trials could be

    due to a familiarity with the researcher and the participants being more comfortable with

    performing the running trials and the training protocols. Also, the pre- and post-training

    weight of the participants was not formally measured by the researcher, but fat loss could be

    a reason for the improvement seen in sprint time. Also, in conversation with some of the

    participants from the HR group indicated that muscle mass may have increased. This may

    indicate that the participant put on muscle mass and this gain could also be a reason for a

    significant improvement among the pre- to post-test times.

    The sprint trials were conducted outside and with a tail wind, so the wind conditions

    may have affected the pre- and post-test trial times due to the seasonal wind speeds. It should

    be noted that sprint times considered to be wind-aided, for example greater that 8.95 mph

    (NCAA, 2011), are not counted toward the qualifying marks to compete at Nationals.

    Excessive wind speeds during the pre- and post-test trials were controlled for by the

    researcher in not allowing the participants to complete their trials if the sustained wind

    exceeded 15 mph. The pre-test sprint trials were conducted in sustained wind speeds of less

    than 5 mph for all participants, but averaged 12 mph during the post-test. However, the

    significant difference (p < .001) in sprint times between trials suggests that the improvement

    is unlikely to be due solely to increased wind speeds.

  • 33

    Conclusions

    The experimental hypothesis was not supported in this study because it did not meet

    the set level of significance (p < 0.05) as a predictor of training protocol influence on sprint

    performance. Both training groups improved sprint time from the pre-test to the post-test

    within the eight weeks of training. It could be suggested that both training protocols can help

    students and athletes improve their sprint performance. Based on the information from this

    study it may be important for people involved in sprinting, coaching, and other sports to

    understand that a shorter amount of time for training, not only the training protocol, can

    produce an improvement in sprint time. However, it is unrealistic for physical educators and

    coaches to determine the effects of the training protocols on the sprint phases of their

    students and athletes because they may not have access to the high speed video equipment

    and force platforms used by previous researchers. A select untrained population was used for

    this study; therefore, the results may not hold true for other populations such as children,

    older adults, athletes, or the general population who regularly train and are interested in

    overall wellness.

    Considerations for Future Research

    The findings from this study have generated new ideas that could be of interest to

    individuals involved in athletics, training, physical education, and in sports which require

    sprinting. This study could also provide information to coaches and athletes about training

    programs that will improve performance in the 100 m sprint.

    Since both training protocols produced an improvement in sprint time, it would be of

    interest to compare a combination of both HR and HV protocols to determine the amount of

    significant change that may occur compared to HV training alone. Faigenbaum and

  • 34

    colleagues (2007) conducted a study which compared the effects of a 6-week training period

    of combined plyometric and resistance training and resistance training alone. The study

    found that the combined group made considerable improvements in the shuttle run compared

    to that of the resistance training group alone; therefore, combining the training protocols

    might provide insight for professionals for improving the speed of their athletes and students.

    Also, this study only looked at females between the ages of 14 years and 18 years of

    age. It could also be of interest to examine other age groups within a different regional

    setting to determine if the training protocols will produce a significant change in sprint time.

    Many studies have been conducted on male participants who were soccer and elite sprinters,

    therefore, another consideration could be to look at female athletes as well. This study

    provides information not only about females, but also about regular physical education

    students for whom little research is available.

    This study used specific training exercises to see if any change in sprint time would

    occur. A consideration would be to change up the sets, repetitions, and exercises used in the

    protocols to see which combination of exercise induces a greater change in the sprint time

    performance. For example, the students could perform more or fewer repetitions of the

    exercises, or add different plyometric jumping exercises (i.e., plyometric boxes, jump squats,

    and other bounding exercises).

    Lastly, the length of the current study was only eight weeks of training. It would be of

    interest to see the minimum number of weeks that would induce a significant change in the

    sprint time performance based on the training program of the participants. This information

    might help professionals reduce injury among the population they are working with by

  • 35

    shortening the training time along with helping physical educators improve their students

    performance in class.

  • 36

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    sprinting performance. Journal of Sports Medicine and Physical Fitness, 35, 13-19.

  • 39

    APPENDIX A: Informed Consent Forms

  • 40

    INFORMED CONSENT FORM

    Comparison of Strength Training Methods on Sprint Time Performance

    Your daughter is invited to participate in a research study to be conducted by Tracie L. Edwards. Your teenager is currently enrolled in the Roswell ISD physical education classes, and this new study will be conducted within this program. The purpose of the study is to examine the effect of two different strength training programs on 100 m sprint time performance among high school female physical education students. Your daughter was selected as a possible participant because she is in the age group of interest. The researcher will ask the volunteers about their current knowledge and experience with strength training programs. Data will be analyzed from volunteers who have no prior experience with strength training programs; however, if the volunteer has current knowledge of strength training programs they will be allowed to participate in the program but their data will not be used for analysis.

    Specifically, I am asking for parent approval along with student approval to participate in the collection of 100 m sprint time data from your daughter and have her participate in one of two different strength training programs for 8 weeks. I will visit the school to ensure the students complete the training exercises for that particular day. An explanation of the procedure follows:

    The procedure begins with student participating in an explanation of the timing equipment being used then various warm up (stretching) exercises. The students will then complete two trials of a 100 m sprint for their best time. During the timed trials each student will individually perform the 100 m while the rest of the participants while watching from the starting line. The students time will be kept confidential from everyone but the researcher and their identity will be coded. At the end of the timed trials all of the students will be randomly placed into two training groups to begin their strength training programs. The high-resistance training program includes exercises such as leg press, leg extension, hip extension, hip flexion, hamstring curl, calf raise, bench press, seated rows, and arm curls and the high-velocity training program includes standing broad jumps, vertical jumps, hurdle jumps, skipping, bounding, and hopping. For the next 2 weeks the students will participate twice a week in their assigned training program. At the end of the first two weeks the students will increase their training to three days a week. At no time will students be left unattended while the participating in the timed trials or during their training program. At the end of the 8th week of training the students will complete two time trials in the 100 m sprint to determine if their times have changed.

    In addition, your daughter will need to wear the appropriate clothing and footwear to participate in this study and the proper exercise equipment will be used at all times.

    There are no foreseeable risks or discomforts, above those that might be expected during physical activity (fatigue or soreness), associated with collection of this data. Please note, any student who expresses a desire to not participate in training on any occasion will be allowed to stop immediately and if the participant wishes to withdraw from the study at any time they will be allowed without any repercussions. I plan to use information obtained from the sprint times in any way thought best for education and publication. I will present the results of this study to my committee and dean at the end of the semester. All data will be collected and stored in a confidential way (code lists will be kept in a locked cabinet), and the students results will be reported anonymously at all times.

    By signing this form, you are agreeing to the participation of your teenager in these strength training programs. Your daughters participation or refusal to participate in the data collection will in no way affect her standing in school nor positively or negatively impact her grade in the physical education class. At the conclusion of the study, a summary of results will be made available to interested parents/guardians and educators. Should you have any questions or desire further information, please call Dr. Sarah Wall at (575) 562-2915 [[email protected]]. For more information regarding your rights as a subject you may contact the Dr. Darren Pollock, Chair of the Human Subjects Committee (575) 562-2862 [[email protected]].You will be provided of a copy of this form to keep.

  • 41

    HAVING READ THE INFORMATION PROVIDED YOU MUST DECIDE WHETHER OR NOT TO ALLOW YOUR DAUGHTER TO PARTICIPATE. YOUR SIGNATURE INDICATES YOUR WILLINGNESS TO ALLOW HER PARTICIPATION IN THE STUDY.

    Student Name (Print)_______________________________ Date________________ Parent/Guardian Signature___________________________ Date________________ Investigator Signature______________________________ Date________________

  • 42

    INFORMED CONSENT FORM

    Comparison of Strength Training Methods on Sprint Time Performance

    You are invited to participate in a research study to be conducted by Tracie L. Edwards. You are currently enrolled in the Roswell ISD physical education classes, and this new study will be conducted within this class. The purpose of the study is to examine the effect of two different strength training programs on 100 m sprint time performance among high school female physical education students. You were selected as a possible participant because you are in the age group of interest. It is necessary for you to have no previous experience with strength training programs to participate in the data collection. We feel this previous experience may change the outcome of the study due to the familiarity with the equipment that will be used. However, if you have participated in strength training programs you still will be allowed to participate alongside your peers but your data will not be used for the study.

    Specifically, I am asking for your (student) approval to participate in the collection of 100 m sprint time data and your participation in one of two different strength training programs for 8 weeks. I will visit the school to ensure you complete the training exercises for that particular day. An explanation of the procedure follows:

    The procedure begins with you (student) participating in an explanation of the timing equipment being used then warm up (stretching) exercises. Next, you will run two 100 m sprints for your best time. During the timed trials you will individually perform the 100 m while the rest of the participants encourage and cheer you on to perform your best while watching from the starting line. No one will know your time and your identity will be coded. At the end of the timed trials all of you will be placed into one of two training groups, high-resistance or high-velocity. The high-resistance training program includes exercises such as leg press, leg extension, hip extension, hip flexion, hamstring curl, calf raise, bench press, seated rows, and arm curls. The high-velocity training program includes standing broad jumps, vertical jumps, hurdle jumps, skipping, bounding, and hopping. For the next 2 weeks you will participate twice a week in your assigned training program. At the end of the first two weeks you will train three days a week. At no time will you be left alone while participating in the timed trials or during your training program. At the end of the 8th week of training you will again complete the 100 m sprint trials to determine if your times have changed.

    In addition, you will need to wear the proper clothing such as shorts, wind pants, and t-shirt, and correct running style shoes to participate in this study and the proper exercise equipment will be used at all times.

    There are no foreseeable risks or discomforts, above those that might be expected during physical activity (i.e. soreness or fatigue), associated with collection of this data. Please note, if you expresses a desire to not participate in training on any occasion you will be allowed to stop immediately and if you wish to withdraw from the study at any time you will be allowed without any consequences. I plan to use information obtained from the sprint times in any way best for education and publication. I will present the results of this study to my committee and dean at the end of the semester. All data will be collected and stored in a confidential way (code lists will be kept in a locked cabinet), and the students results will be reported anonymously at all times.

    By signing this form, you are agreeing to your participation in these strength training programs. Your participation or refusal to participate in the data collection will in no way affect your standing in school nor positively or negatively hurt you grade in the physical education class. At the conclusion of the study, a summary of results will be made available to interested parents/guardians and educators. Should you have any questions or desire further information, please call Dr. Sarah Wall at (575) 562-2915 [[email protected]]. For more information regarding your rights as a subject you may contact the Dr. Darren Pollock, Chair of the Human Subjects Committee (575) 562-2862 [[email protected]].You will be provided of a copy of this form to keep.

  • 43

    HAVING READ THE INFORMATION PROVIDED YOU MUST DECIDE WHETHER OR NOT YOU ARE ALLOWING YOURSELF TO PARTICIPATE. YOUR SIGNATURE INDICATES YOUR WILLINGNESS TO ALLOW YOUR PARTICIPATION IN THE STUDY.

    Student Name (Print)______________________________ Date________________ Student Signature_________________________________ Date________________ Investigator Signature______________________________ Date________________

  • 44

    APPENDIX B: High Resistance Training Workout

  • 45

    High-Resistance Training Workout

    Sets X Repetitions

    Week 1-2 Week 3-4 Week 5-6 Week 7-8

    Leg Extension 3 X 8 RM 3 X 8 RM 3 X 8 RM 3 X 8 RM

    Hamstring Curl 3 X 8 RM 3 X 8 RM 3 X 8 RM 3 X 8 RM

    Hip Extension 3 X 8 RM 3 X 8 RM 3 X 8 RM 3 X 8 RM

    Hip Flexion 3 X 8 RM 3 X 8 RM 3 X 8 RM 3 X 8 RM

    Squat 3 X 8 RM 3 X 8 RM 3 X 8 RM 3 X 8 RM

    Leg Press 3 X 8 RM 3 X 8 RM 3 X 8 RM 3 X 8 RM

    Calf Raise 3 X 8 RM 3 X 8 RM 3 X 8 RM 3 X 8 RM

    *The weight will be progressively increased to maintain 8 RM.

  • 46

    APPENDIX C: High Velocity Training Workout

  • 47

    High-Velocity Training Workout

    Instructions

    Exercises Reps Series Evaluation

    Standing Broad Jumps 5 3 Distance

    Vertical Jumps 5 3 Height

    Cone Jumps 5 3 Height

    Skipping 20 1 Time

    Leg Frequency/Ladder 20 1 Time

    Bounding 5 4 Distance

    Hopping 5 4 Distance

  • 48

    APPENDIX D: Pre- and Post-Test Times and Change Scores

  • 49

    Pre- and Post-Test Times and Scores

    Participant Number Pre Post

    Change Score

    Group Pre Post Change Score 1 16.16 16.05 -0.11 HV 20.57 19.72 -0.85

    2 20.63 18.91 -1.72 HR 20.04 19.18 -0.86

    3 23.62 21.55 -2.07

    4 18.36 17.55 -0.81

    5 22.90 21.59 -1.32

    6 20.21 18.56 -1.65

    7 18.50 19.44 0.93

    8 20.38 20.99 0.61

    9 18.75 17.85 -0.90

    10 22.27 20.58 -1.69

    11 16.11 16.51 0.40

    12 19.83 18.94 -0.89

    14 21.03 20.34 -0.69

    15 23.77 21.97 -1.80

    16 19.99 17.44 -2.55

    17 17.84 18.37 0.54

    18 19.69 18.29 -1.40

    19 20.75 20.37 -0.38

    20 20.21 19.61 -0.59

    21 23.13 23.99 0.85

    23 20.11 19.36 -0.75

    25 21.79 22.02 0.23

    27 18.70 17.67 -1.03

    28 18.68 17.91 -0.76

    29 22.41 22.40 -0.01

    30 20.18 17.12 -3.06

    31 20.19 20.16 -0.03

    32 20.18 19.96 -0.23

    33 20.35 20.38 0.03

    34 22.96 20.08 -2.88