Biomechanical Analysis of The Complete Core Conditioner

Corresponding Author: Brandon HossackEngineering and Human Performance Lab, University of Lethbridge

683 Heritage Boulevard West, T1K 7E61(403)619-1509brandonhossack@gmail.com

BACKGROUND: Core stability competence has seen an increase in attention due to the possible linkage between acute training effects, as well as long-term health benefits. A substantial amount of core exercise machines have stated the advantage of training they may provide, but innovative machines are on the rise. OBJECTIVE: This study is to provide insight and scientific evidence as to whether or not the Complete Core Conditioner will provide an increase in core exercise intensity for acute and/or long-term health benefits. METHODS: A sample of 9 university students were subjected to exercises involving flexion and extension about the trunk both on and off of the Complete Core Conditioner. Data was analyzed to determine whether the Complete Core Conditioner provided a workout of increased intensity.RESULTS: The Complete Core Conditioner provided subjects with an increase in range of motion, but not in maximal velocity throughout each exercise. CONCLUSIONS: Although the Complete Core Conditioner provided an increase in range of motion suggesting a higher intensive workout, further research is needed to validate the suggested increased effects of core stability exercise on this machine.

Keywords: Complete Core Conditioner, Core Exercise, Core Stability, Core Strength, Range of Motion, Movement Velocity.

INTRODUCTION

Core exercise has become increasingly popular for not only the acute effects of strength maximization or aesthetics but has also been associated with improving athletic performance, injury prevention, and the potential capacity for alleviating low back pain [1]. Due to the rise of public obsession with the linkage core training has with bodily aesthetics, exercise machines have been innovated to incorporate the maximal amount of core training in the shortest given time period of exercise. Although this could be considered as a significant driving factor in technological advancements involving core training, innovators have also considered the benefits of core stability due to core exercise with a more long-term approach. Helping with postural control and movement efficiency, satisfactory core stability and coordination can prevent compensatory movement patterns that often lead to strain and overuse injuries [1]. The purpose of this study was to determine whether or not the Complete Core Conditioner would provide a patient or exerciser with an increased intensity of exercise when comparing similar abdominal exercises to those commonly performed on the floor to achieve this standard in a more efficient manner.

Anatomically, the core is defined to include not only the axial skeleton, but also all soft tissue with proximal attachment points to the axial skeleton itself [2]. Core exercises are designed to innervate maximal amounts of these muscles in a coordinated manner to ensure that there is not an offset of strength gains, leading to the possibility of injury or future lower back pain (LBC). The rectus abdominis, internal and external obliques, and transverse abdominis are the most common muscles incorporated with concentric flexion of the trunk, and resisting

isometric or eccentric extension about the hips [3]. For this reason, we tested the Complete Core Conditioner through a series of exercises primarily involving flexion and extension of the trunk.

It has long been debated as to whether core stability exercise is more beneficial than general exercise for the treatment of low back pain. Past research has found through a meta-analysis that core stability exercise is more effective in decreasing acute pain and may improve physical function in those with lower back pain (Wang, Zheng, Yu, Bi, Lou, Liu, Cai, Hua, Wu, Wei, Shen, 2012)[4]. This has driven scientists and innovators to developing an abdominal exercise machine that targets core stability programs, but also possesses the novelty of time efficiency. To do so, exercise intensity must be increased through each repetition of the exercise program.

Full range of motion (ROM) should be considered when applying core stability exercises to a workout regimen. By subjecting themselves to shortened ROM, patients and exercisers are only maintaining, or improving, partial segments of their muscles. More specifically, the gains of strength or stability are localized to the ranges at which the muscles are being activated throughout the particular exercise repetition. This eventually leads to instability within the core and limited postural stability if not corrected early. Utilizing a full ROM throughout a particular exercise is essential, as it will provide greater strength gains throughout the full length of the muscle [5]. This leads to more even distribution of strength, and does not limit core stability and postural control in various positions. Through an increased range of motion the exerciser or patient will find an increase in exercise intensity. There is more work being performed within each

repetition, in turn, proving to be a more efficient exercise for training or maintaining strength. This study examines the extent to which the CCC can improve or impede range of motion through various core stability exercises.

Movement velocity has also been linked to exercise intensity. Recent literature (Conceição, Fernandes, Lewis, Gonzaléz-Badillo, Jimenéz-Reyes, 2015) found a strong relationship between maximum instantaneous movement velocity within an exercise repetition and the %1RM among participants in a study involving three lower body exercises [6]. Using a linear regression equation, an individual’s %1RM can be accurately predicted from the movement velocity incorporated with submaximal loading. Through the correlation of movement velocity and exercise intensity, this study also uses the movement velocity of subjects throughout exercise on the Complete Core Conditioner and compares it with that of similar exercise on a more traditional, flat surface.

METHODS

ParticipantsStudents from the University of Lethbridge were recruited for this study and compensated with participation marks that would contribute to their cumulative grade in their respective courses from which they were introduced to the study. There were 23 males and females recruited, but only 9 of them contributed data towards analysis for this study. All subjects were students at the University of Lethbridge and completed a PAR-Q assessment to assess whether or not the individual was capable in performing a short bout of exercise. Each subject was able to complete the warm-up, exercise bout, and debrief in a half hour.

Experimental ProceduresTo analyze the relationship of

exercise intensity of specific exercises performed on the CCC and similar exercises performed on the floor, a cross-sectional study design was used.

Originally, researchers had designed pilot tests involving self-designed exercises that were tailored to both the CCC as well as a flat surface such as a mat or the floor. Subjects found some of the exercises too difficult, or were unable to properly position themselves on the CCC to accommodate the exercise. Because of these pilot tests we were better able to design exercises and assess subjects through more basic core stability movements on both the CCC as well as the floor. Furthermore, the warm-up for each of the subjects had not been formerly established, so data collected from inconsistent subject procedures were not taken into account. The data obtained from the pilot tests were not included in this study.

Upon entering the lab in which the CCC was located, subjects were introduced to the researchers and familiarized with the CCC itself. Full explanation was given as to why the study was being conducted, and questions were answered regarding the machine or the study in general. Each of the subjects was then introduced to the warm-up consisting of a low intensity aerobic exercise that provided the subject with movement through extensive ranges of motion.

Subjects were randomized to perform the exercises on the floor first, followed by the same exercises on the CCC, and vice versa. This was to ensure fatigue was not reflected in the results and did not influence movement behaviour in accordance to the particular setting for each exercise.

Including the most common muscle(s) involving flexion and extension of the trunk, we used three exercises commonly

used in core training on the floor or a flat surface. These included a pronated leg raise (figure 1), a supine crunch (figure 2), and a supine leg crunch (figure 3). The latter of the three utilized more lower body movement than the supine crunch. Each subject was to perform the three exercises on the floor as well as the modified version on the CCC. Again, randomized order was enforced, although exercises involving either the CCC or the floor were done together. The subject was to complete 5 repetitions of each of the three exercises beginning with the floor or the CCC, and would continue to do the same three exercises in the complimentary setting, in sequential order. The pronated leg raise was tested first, supine crunch second, and the supine leg crunch last. Participants were instructed how to properly complete each exercise through demonstration of continual repetitions. Constant supervision was provided to ensure postural features were maintained throughout each of the exercises in order to establish continuity among exercises for each of the subjects. If a participant was to deviate from the given exercise, verbal instructions were made clear. For example, ‘bend your knees’ during the supine leg crunch, or ‘maintain a 90 degree angle at the knee joint’ during the supine crunch.

Once three exercises had been completed on the floor or the CCC, the subject would switch settings and perform the same three exercises. Verbal instructions and further demonstrations were given between each exercise. Subjects were continually told to focus more on the movement patterns of each exercise rather than completing the repetitions as fast as possible.

There were no exclusion criteria for this study, however it was required to have completed a PAR-Q assessment to ensure safety throughout the testing.

InstrumentationOnce questions from the subjects had

been answered and each of them had been introduced to the procedures of the study, they were asked to complete a Physical Activity Readiness Questionnaire (PAR-Q) assessment. This asked simple questions relating to the physical capabilities of low to moderate exercise, and whether it was safe to do so for each of the participants. Prior to being subjected to any form of exercise, the subject’s completed PAR-Q assessment was examined by the researcher to ensure safety was controlled.

The subjects were then put through a warm-up consisting of low intensity aerobic exercise. The song titled ‘Head and Shoulders, Knees and Toes’ from the album titled PLAY; Action Songs for Kids was played at low to medium volume. Each subject was to follow along with the words and touch the spoken body segment. This was to emphasize the flexion and extension of multiple joints while incorporating submaximal ranges of motion and lightly increasing heart rate.

The Complete Core Conditioner provided the subjects with an opportunity to execute each exercise with different postures and varying grip points. Although these can be manipulated for comfort, we ensured handles were positioned in consistent locations for each of the subjects.

Infrared cameras were used for motion capture in the Engineering and Human Performance Lab located within the University of Lethbridge. Reflective markers were attached by adhesive material to each of the subject’s primary joints that would undergo change in a core stability exercise. These included the shoulder, elbow, wrist, hip, knee and ankle on both sides of the body. Vicon Motus software enabled researchers to digitize the motion of each of the markers and correctly label them with each of the corresponding joints.

The exercises were performed on the CCC, and on the floor covered by a thin carpet comfortable enough for abdominal exercises.

Data CollectionAs the subjects performed each of

the exercises both on the CCC and on the floor, infrared cameras would monitor the displacement of each of the markers distributed on each of the joints of the subject. This was then digitized through the Vicon Motus computer software program and as previously stated, labelled with the corresponding joint. Subjects that wore flashy clothing prevented accurate digitization and were not included within the data analysis for this study.

To determine the range of motion of each exercise, the joint undergoing the highest resultant displacement was recorded. For example, the supine leg crunch involved moving the knees toward the chest, with extremely little movement from the upper body. Due to this, measuring the ankle markers would be most beneficial in determining not only the resultant displacement, but also the maximal movement velocity for the exercise. This was consistent for the pronated leg raise, as the lower body was the location for primary movement. In contrast, the supine crunch incorporated fixed ankles and knee joints with an upper body movement to bring the shoulders up from the ground, or furthest eccentric position. To monitor the movement of the supine crunch, resultant displacement and maximal movement velocity was recorded from the wrists of each subject. At no point in time were the subjects instructed to complete a repetition as fast as possible, but were encouraged to go about the repetition as if they were to be exercising in a routine setting.

The absolute values for maximal instantaneous velocity (metres per second)

was averaged from all frames captured by the infrared cameras, and again averaged between both the left and right of either the wrists or ankles. The same was done for the resultant displacement (metres).

Data AnalysisOriginally, all the digitization data

were transferred to an excel spreadsheet. Organization was done, and tables and graphs were made in accordance to exercise type and location (setting) of each exercise.

Using a repeated measures ANOVA test, we combined the three exercises to analyze the effect of two independent variables on effectiveness of the Complete Core Conditioner through range of motion and movement velocity. The two independent variables were the location (setting) of the exercise and the exercise test type. The location had two conditions: on the floor, or on the CCC. The exercise test type involved three different core stability exercises: the pronated leg raise, the supine crunch and the supine leg crunch.

Statistical ProceduresBoth the resultant displacement was

recorded to analyze the range of motion in accordance to each exercise as well as the maximum movement velocity in an excel spreadsheet. Through the repeated measure ANOVA the range of motion was compared between the exercise types on the CCC and on the floor. The velocity data were compiled in a similar fashion to directly compare the differences between the exercise on the CCC and the floor. An alpha level of 0.05 was established for statistical significance level.

RESULTS

There was no statistical difference in maximum movement velocity (p>0.05) amongst the exercises performed on the

floor and on the CCC. However, there was a statistical difference (p<0.05) in resultant displacement vectors amongst the exercises performed on the floor and on the CCC. As the subjects performed the exercises on the floor and on the CCC, a greater range of motion was found to be consistent with the displacement of the primary moving joint throughout exercises performed on the CCC.

CONCLUSION

The results obtained from this study prove to highlight the effectiveness of the CCC in increasing the range of motion throughout three core stability exercises. These exercises are the pronated leg raise, supine crunch, and supine leg crunch. Although maximum movement velocity was also tested, there was no significant difference between the primary moving joints (ankles or wrists) amongst the exercises performed on the floor vs. the CCC.

In reference to previously established notions, the increased range of motion provided by the CCC helps to maximize core stability by stretching the muscle groups of the abdomen to maximal lengths. Involving the rectus and transverse abdominis and the internal and external obliques, flexion and extension exercises have been provided with larger resultant displacements by utilizing the features of the CCC.

Although there was a slight difference in movement velocity, it can possibly be attributed to the materials on which the exercises were performed. For example, the pronated leg raise was performed on a flat surface with little to no

elastic qualities. As the subject performed the pronated leg raise on the CCC, there may have been additional movement velocity recorded due to the elastic effects of the Swiss ball. With this being said, there was no significant difference found in maximum movement velocity when comparing the exercises performed on the floor and the CCC.

This study suggests there to be an increased exercise intensity provided from the CCC through an increased range of motion in accordance to core stability exercises focusing on flexion and extension of the trunk. The findings may correlate to increasing core strengthening techniques, but may also be implied to the possibility of preventing acute low back pain and correcting postural imbalances within the core musculature.

LimitationsThis particular study only utilized 9

subjects out of 23 that had originally signed up to participate. This was due to lack of knowledge on the CCC itself, and what would be appropriate testing methods for each of the participants. Further research could use this research as a pilot study to incorporate more subjects from the beginning of testing.

Furthermore, more exercises involving a variety of movements could be incorporated into the testing method. Although core stability involves more than just flexion and extension [1], rotation can be incorporated to assess a more appropriate core stability program.

ACKNOWLEDGEMENTS

The author would like to thank Dr. Jon Doan of the Engineering and Human Performance Lab in the University of Lethbridge for his time and lab setting for this study, Mr. Stephane Simard for providing insight throughout the study, the students of the University of Lethbridge who participated in the study, and the colleagues that helped in various manners.

REFERENCES

[1] Akuthota, V., Ferreiro, A., Moore, T., & Fredericson, M. (2008). Core stability exercise principles. Current sports medicine reports, 7(1), 39-44.[2] Behm, D. G., Drinkwater, E. J., Willardson, J. M., & Cowley, P. M. (2010). The use of instability to train the core musculature. Applied Physiology, Nutrition, and Metabolism, 35(1), 91-108.[3] Escamilla, R. F., McTaggart, M. S., Fricklas, E. J., DeWitt, R., Kelleher, P., Taylor, M. K., ... & Moorman III, C. T. (2006). An electromyographic analysis of commercial and common abdominal exercises: implications for rehabilitation and training. Journal of Orthopaedic & Sports Physical Therapy, 36(2), 45-57.[4] Wang, X. Q., Zheng, J. J., Yu, Z. W., Bi, X., Lou, S. J., Liu, J., ... & Shen, H. M. (2012). A meta-analysis of core stability exercise versus general exercise for chronic low back pain. PloS one, 7(12), e52082.[5] Drinkwater EJ, Moore NR, Bird SP. Effects of changing from full range of motion to partial range of motion on squat kinetics. The Journal of Strength & Conditioning Research. 2012 Apr 1;26(4):890-6.[6] Conceição, F., Fernandes, J., Lewis, M., Gonzaléz-Badillo, J. J., & Jimenéz-Reyes, P. (2015). Movement velocity as a measure of exercise intensity in three lower limb exercises. Journal of sports sciences, 1-8.

FIGURE CAPTIONS

Figure 1. Pronated Leg Crunch, both on the CCC and on the floor.

Figure 2. Supine Crunch, both on the CCC and on the floor.

Figure 3. Supinated Leg Crunch, both on the CCC and on the floor.

Figure 4. Maximum movement velocity (metres/second) comparing exercises on the floor to the exercises on the CCC; no significant difference (p>0.05)

Figure 5. Average resultant displacement (metres) comparing exercises on the floor to the exercises on the CCC; significant difference (p<0.05)

FIGURES

Figure 1.

Figure 2.

Figure 3.

Figure 4.

Figure 5.