Journal of Strength and Conditioning Research. 2005. 19(3), 647-651© 2005 National Strength & Conditioning Association

THE BENEFITS OF A FUNCTIONAL EXERCISE CIRCUITFOR OLDER ADULTS

MICHAEL A. WHITEHURST,^ BEVERLY L. JOHNSON,^ CHERIE M. PARKER,^ LEE E . BROWN,' AP4DALLISON M. FORD'

'Department of Exercise Science and Health Promotion, Florida Atlantic University, Davie, Florida 33314;-'DeVos-Blutn Family YMCA of Boynton Beach, Boynton Beach, Florida 33435; 'FACSM Division of Kinesiologyand Health Promotion, California State University, Fullerton, California 92834.

ABSTRACT. Whitehurst, M.A., B.L. Johnson, CM. Parker, L.E.Brown, and A.M. Ford. The benefits of a functional exercise cir-cuit for older adults. J. Strength Cond. Res. 19(31:647-651.2005.—The physical benefits of a functional exercise circuit arenot well known in an elderly population. The purpose of thisstudy was to evaluate the effect of a functional exercise circuiton mobility and perceived health in the elderly. Subjects were119 men and women (aged 74 |:r4.2| yearsi who received pre-and posttests of mobility (e.g., sit to stand, get up and go, timedwalk), flexibility (sit and reach), and balance (standing reach!and who completed the Medical Outcomes Study 36-Item Short-Form Health Survey (SF-361. A supervised functional exercisecircuit that included 10 different upper- and lower-body exercis-es performed under time constraints was performed 3 times perweek for 12 consecutive weeks. Paired /-tests showed siffnificantdifferences at posttest for the get up and go (p < 0.001), standingreaeh ip < 0.001), sit and reach (p < 0.001). and selected itemsfrom the SF-36, including physical functioning ip < 0.001), painip = 0.001), vitality ip = 0.001), and number of doctor visits ip< 0.001). A functional exercise circuit such as the one employedin this study may offer promise as an effective means of pro-moting mobility and perceived health in older adults.

KEY WOUDS. enhanced mobility, perceived health

INTRODUCTION

hile resistance exercise has been used exten-sively during the past decade to promotestrength, muscle hypertrophy, and mobilityin the elderly (6, 7, 10, 17), few if any studieshave reported using a functional approach in

which movement patterns common to activities of dailyliving (ADL) were employed as the primary exercise stim-ulus. The idea that exercise should be strict linear move-ments typical of resistance machines and free weightsmay be impractical for many older adults. Rather, a func-tional exercise, particularly one performed in a circuitfashion, may be well suited to older persons wishing toimprove function and mobility.

Using an exercise circuit to induce physiological stressin an effort to promote health-related fitness is not new.For example, circuit weight training has been shown toimprove strength and, to a lesser extent, cardiorespira-tory endurance in young, healthy subjects (8, 19). Simi-larly, circuit or workstation exercise interventions havebeen used to improve function and physical work capacityin stroke patients (4, 12) and cardiac patients (5). In arecent study, Nelson et al. (13) exposed older adults to ahome-based exercise program that included progressiveresistance exercise and mobility challenges. Nelson andcolleagues found significant improvements in dynamic

balance, whereas strength and gait speed did not differbetween exercise and control groups. Although the au-thors concluded tbat a home-based exercise program of-fers benefits, it could he argued that their failure to findsignificant results across all outcome measures resultedfrom the older subject's inability to perform exercises cor-rectly in the absence of feedback and/or sustain an ap-propriate intensity throughout tbe exercise session.

Our intention was to develop a functional exercise cir-cuit tbat required movement patterns and mobility chal-lenges common to ADL. In doing so, we sought to providea supervised exercise setting and effectively eliminate theneed for specialized equipment while providing physicallydemanding exercise performed in a group setting. We hy-pothesized that the f̂ unctional exercise circuit would pro-vide an exercise stimulus suitable for improving function-al mobility in older adults. In addition, considering thata psychologic benefit is often attributed to regular exer-cise (1), we examined the influence of the functional ex-ercise circuit on perceived health. Again, consistent withother forms of exercise, we hypothesized that the benefitsof the functional exercise circuit would extend beyond thephysical.

METHODS

SubjectsThis study sought to determine whether elderly subjectscould improve tbeir mobility and perceived health from anontraditional functionally (i.e., movement patterns com-mon to ADL) based exercise program. This study was ap-proved by Florida Atlantic University's Institutional Re-view Board for Human Subjects Research. Subjects were119 (aged 73 I ±4.61 years) volunteers from Palm BeachCounty, Florida. Upon phone inquiry, subjects werescheduled for a physical examination (an informed con-sent and a detailed medical history were also obtained).Subjects whose medical history and/or physical exami-nation showed more than 2 major coronary heart diseaserisk factors and/or who presented with an unstable con-dition (e.g., heart disease, high blood pressure, abnormallevels of blood lipids) within the last 12 months and/orwho had mobility issues were referred to their physicianfor follow-up [n = 3) and deemed unfit for participationin this study.

Immediately following the physical examination, sub-jects completed the Medical Outcomes Study 36-ItemShort-Form Health Survey (SF-36) and a battery of teststhat targeted mobility (e.g., sit to stand, get up and go,timed walk), fiexibility (sit and reach), and balance

647

648 WHITEHURST, JOHNSON, PARKP:K ET AL.

(standing reach). The SF-36 (numeric responses, e.g., 1 =all of the time; 6 -- none nf the time) dealt with generalhealth, physical functioning, mental state, social activity,pain, and vitality. Subjects were also asked to provide thenumber of falls, emergency room visits, hospitalizations,and doctor visits, where pretest was defined as 12 monthsprior to their participation in this study. All tests wererepeated within 1 week following the conclusion of the 12weeks of continuous exercise.

ProceduresThe sit-to-stand maneuver was electronically timed andrequired the suhject to rise from a seated to a standingposition, without the aid of the arms, as quickly as pos-sible. The best of 3 trials was recorded. A detailed de-scription of this test may be found elsewhere (18).

The get-up-and-go test required the subject to risefrom a seated position, walk 8 ft (2.44 m), turn, and re-turn to the seated position as quickly as possible (14).

The timed walk test was an aerobic endurance testlasting 6 minutes. Briefly, the subject walked a rectan-gular course (13.4 X 3.35 m) for 6 minutes, covering asmuch distance as possible (14).

Fiexihility was measured in the sit-and-reach positionusing a standard sit-and-reach hox, and the best of 3 tri-als was recorded (9).

The standing-reach test was a field test of balance andprovided a measure of the subject's stability and risk offalling. Subjects stood with the shoulder of the dominantarm next to a wall. Affixed to the wall was a slide. Thestart position was defined as the subject grasping thehandle of the slide mechanism, arm in front of the bodyand parallel to the fioor. The subject moved the slidemechanism forward by leaning forward as far as possibleor just prior to tbe point that a step was necessary toavoid falling. The distance from the start position (mea-sured from the handle on the slide mechanism) to thestopping point was recorded. Each subject received 3 tri-als, and the greatest reach was recorded. All tests wereadministered in the order described.

Functional Exercise Circuit—OverviewA functional exercise circuit was performed 3 times perweek for 12 consecutive weeks. The circuit consisted of 10exercises or stations performed consecutively, each last-ing 60 seconds, with 3 circuits completed each session.During the 60 seconds, participants were able to complete10-30 repetitions before transitioning (15-20 seconds) totbe next station. A total of 15-30 subjects participated ineacb session. Subjects were monitored at all times to en-sure safety and adherence to good form and were in-structed to avoid the Valsalva maneuver while perform-ing the different exercises in the circuit. Subjects werenot allowed to complete more than several repetitions ateach station of the circuit for tbe first week. More repe-titions and hence difficulty were introduced slowly duringsubsequent weeks (weeks 2-3). A timer called out times(e.g., 15, 30, 45 seconds) during the 60-second interval.Finally, subjects wore a heart rate monitor while exercis-ing and were instructed to monitor tbeir intensity bychecking their monitor periodically (training beart rate =70-80*^ predicted maximum heart rate) as well as usingthe Borg scale (13-14). Periodic inspections by the inves-tigators showed that subjects were at or just below 70%of tbeir THR during the functional exercise circuit. Of the

Woighl lrari\riT: perfornii.'il iivcr cihvl;n;lL' tmirrm-ludinp stopping iiver hurdles. ['iirwiird/baL-kwalking, slLins and suips and rapid directional

V.,it

tSuperman

tCrunch

tMixiillcii push-gp

FIGURE 1. Layout of functional exercise circuit,

36 possible sessions, subjects averaged slightly more than30 sessions or 83*}? of all possible sessions.

While the stations of the circuit required specificmovement patterns, the circuit was designed to empha-size level changes, directional changes, and the negoti-ating of ohstacles. In this way, tbe circuit was more thanjust a repetitive process. Rather, the configuration of thecircuit and its inherent obstacles placed cognitive and at-tentional demands on the subjects at all times. The sta-tions were labeled by number and name while the sub-jects rotated tbrough the circuit numerically (1-2 . . . .10-lt. See Figure 1 for a layout of the exercise circuit.

Functional Exercise CircuitWall Exercise. The subject stood with his or her back tothe wall. A large rubber ball (1.06 m) was placed betweenthe midback and the wall. Wbile leaning against the ball,the subject fiexed the knees, trying to attain a 90° bendbefore returning to tbe straight-legged starting position.

Single Leg Balance. With a foam cushion (5.08 cm)positioned near a wall, the subject balanced on 1 leg whilestanding on the foam cushion. This task will was repeatedon both legs, approximately 30 seconds per leg.

CroHs-Legged Seated Torsn. The subject assumed aseated cross-legged position (back straigbt) on the floor toperform a series of 4 gentle stretches. With the arms out-stretched and tbe hands resting on the knees, the first

FUNCTIONAL EXERCISL CIRCUIT AND THE ELDERLY 649

movement included bending forward at the waist andthroughout the spine, in order to move the head towardthe floor, and then returning to the straight-hack posi-tion. The second and third movements required the sub-ject to maintain the straight hack while rotating the torsoposition (arms were allowed to follow the torso hut didnot provide assistance) as far as possihle in one directionand then in the opposite direction. The fourth and finalmovement required the subject to place the hands behindthe buttocks for support while arching the back sueh thatthe chest moved toward the ceiling. Each position washeld for 3-10 seconds and repeated several times in se-quence.

Modified Push-Up. From a kneeling position, thehands were placed on the floor, shoulder width apart, andarms straight. The goal was to lower the chest to the floorand return to the straight-arm position. Suhjects whoeould not perform the modified push-up performed wallpush-ups in which their feet were shoulder width andparallel and as far from the wall as could he toleratedwhile they were still able to flex the arms and move thechest as close to the wall as possihle.

Crunch. While lying on the back, arms crossed againstthe chest and knees bent so the feet were flat on the floor,the subject tucked the chin against the sternal notch andraised the back from the floor as far as possible while, atthe same time, contracting the abdominal muscles suehthat the hack rounded and the chest moved toward thehent knees. The suhjeet held the upright position for 1count before returning the back to the floor and repeatingthe movement.

Superman. While lying facedown on the floor witharms outstretched overhead, the subject lifted the thighsand chest off the floor simultaneously. At the top, the sub-ject paused for 1 count hefore lowering the chest andthighs to the Boor.

V-Sit. The subject assumed a seated position with thelegs outstretched, the back straight (some suhjects placedtheir hands on either side of the hips to assist in main-taining a straight hack), and the feet spread 0.6-1.2 m,depending on individual capability. Alternating hetweenlegs, the suhject leaned toward an outstretched leg as faras possihle. Upon stretching to a comfortable limit, thesuhject paused and held the stretch for 5-10 seconds be-fore returning to the start position. The suhject thenstretched toward the other leg. This process was repeatedseveral times for each leg.

Stretch and Balance. Standing with feet shoulderwidth apart and arms at the sides ofthe body, the subjectreached overhead with the right arm while simultaneous-ly ahducting the left leg such that that foot left the floor.In the outstretched position, the arm and leg formed adiagonal line that was held for as long as 10 seconds. Thesame action was repeated for the other side of the hody.These movements were repeated 2-4 times per side. Suh-jects were allowed to hold a chair with the uninvolvedhand for support.

Star Exereise. Six rubber cones (height ^ 0.07 m) werepositioned in a circle around the subject, with each eoneapproximately 0.094 m from the suhjeet. While balancingon 1 leg, the suhjeet flexed the knee, reached down, andtonehed the top of a cone. The subject returned to theupright posture (starting position) before attempting totouch another eone. It should be pointed out that the suh-jects used opposing limhs (e.g., right leg as the hase and

left arm to touch the cone). Additionally, the subject wasoriented in a constant direction during the task. Thismeant that touching a cone in the rear required hendingand flexing the knee and blindly reaching back. The long-term goal for each subject was for him or her to touch the6 cones with all combinations of balanced leg and out-reaehed arm. However, not all subjects could touch allcones at all times without temporarily losing balance andhaving to temporarily stabilize themselves with the otherfoot.

Weight Transfer. The subject picked up tote bags, onein eaeh hand, representing approximately 20*7̂ of his orher hody weight. With the arms at the sides, the subjectwalked around the outside of the exereise eireuit andthrough or around obstacles that included stepping overharriers (there were 3 to choose from: 4.7, 7.0, and 9.4cm), reversing direction, and walking backward while ear-rying the tote bags.

Statistical AnalysesMean and standard deviation were calculated for eaehvariable. Paired t-tests were used to determine differene-es over time for eaeh variable. The p ^ 0.05 was used. Alldata analysis was completed using SPSS version 11.0(SPSS Inc., Chicago, IL).

R E S U L T S

As shown in Tahle 1, paired ^tests deteeted significantdifferenees in pre- and posttests for get up and go ip =0.000), standing reach Ip ^ 0.000), sit and reach (p =0.000), self-reports of physical functioning (p = 0.001),pain ip ^ 0.001), vitality ip ^ 0.001), and doctor visitsip ^ 0.000). The initial alpha level of p = 0.05 was cor-rected (0.05 per number of paired /-tests or 18).

DISCUSSION

This study sought to evaluate the relative value of a func-tional exercise circuit as a means of promoting mobilityand perceived health in an elderly population. On the ba-sis of the results obtained in the get-up-and-go test, itappears that the functional exereise circuit interventionpromoted mohility. Although not signiflcant (0.006), thetimed walk test, indicative of eardiorespiratory endur-ance and mobility, improved hy 7.47 .̂ These flndings areconsistent with other studies in which mobility improvedin an elderly population following exereise training (6, 7,10). However, unlike previous studies, the current studyemployed movements common to ADL, with resistanceprovided hy the subject's body weight. Given the natureofthe circuit (e.g., directional changes, obstacles) and thetime limit imposed at eacb station, we speculate that aprogressive overload was produced that manifested itselfas improved mohility.

Standing reach, a field measure of stahility and fallrisk, improved 12.9%. This improvement may he a prod-uct ofthe dynamic nature ofthe training regimen. A dy-namic exercise intervention in the form of agility trainingwas employed in a recent investigation by Liu-Ambroseet al. (11). Using body sway as a measure of fall risk,these authors reported a 29.6 and 30.6'> reduction insway following agility and resistance training. Given thatthere was no signifleant difference in hody sway followingagility or resistance training, it could be argued that themore functionally based agility exereise is at least as goodas traditional resistance exercise at reducing the risk of

650 WurTEHURST, JOHNSON, PARKER RT AL.

TABLE 1. Changes in mobility and perceived health following 12 weeks of functional exercise (mean ± SD).Variable

Get up and goSit to standStanding reach (m)Timed walkSit and reach (ni)Physical functioningRole physicalPainGeneral heal thVitalitySocial functioningRole emotionalMental healthFallsEmergency department visitsHospitalizationsDoctor visitsNumber of medications

Test 1

7.92 t. 2.10.78 ± 0.65

0.3432 ± 0.087.5 ± 1.8

0.248 ± 0.1466.5 ± 23.267.2 ± 38.666.8 ± 21.168.9 ± 18.657.5 ± 21.485.3 ± 19.479.2 ± 35.276.0 ± 15.30.18 ± 0.640.11 ± 0.340.08 ± 0.271.34 ± 1.13.87 ± 2.6

Test 2

7.25 ± 2.00.74 ± 1.5

0.386 ± 0.068.1 ± 2.2

0.289 ± 0.1372.7 ± 20.773.9 ± 34.973.2 ± 20.970.1 ± 17.263.5 ± 20.090.0 ± 17.083.1 ± 30.379.5 ± 16.20.08 ± 0.300.03 ± 0.180.01 ± 0.090.91 ± 0.873.68 ± 2.8

•^ change

8.45.1

12.97.4

14.08.59.08.71.79.45.24.74.4

55,572.787.532.0

4.9

Significance

0.000*0.8160.000̂ ^̂0.0060.000 •'0.001*0.1100.001*0.4520.001*0.0060.2520.0080.1310.0380.0060.000 '̂0.110

^ 0.002.

falling in older subjects. Using another form of dynamicexercise, Tai Chi, Wolf et al. (20) found that Tai Chi train-ing redueed the risk of multiple falls by 4T7< compared tothose of an education group. We would suggest that thefunctional exercise circuit employed in this study wassimilar to the aforementioned dynamic training interven-tions. Assuming as much, a functional or dynamic ap-proach may activate the centers for postural control (i.e.,somatosensory, vestibular, visual) (15) with the synapticplasticity occurring in the postural control centers as afunction of repetition and learning (18). Speculatively, anadditional beneflt of the functional exereise circuit wastask complexity. That is, the required movement patternswere not always easy to remember or easy to produce.Hence, the functional exercise circuit represented a con-tinuum of perceptual, cognitive, and action challengesthat, over time, may have affected cognitive and cerebel-lum function as well (16).

The improved sit-and-reach performance was not un-expected. Again, given the dynamic nature of the exer-cise, including level changes and hoth static and dynamicmovements, improved hip and lower-hack flexion was ex-peeted and consistent with the findings of other studiesin which flexibility was targeted through specific exercis-es (2).

Perceptions of physical functioning, pain, and vitalitywere all signifleantly improved following training. As faras physical functioning is eoneerned, there appears to bea relationship between function and mohility, particularlywalking speed (3). Therefore, it is logical to conclude thatimproved mobility was associated with a high degree ofphysical functioning. Similarly, subjects in this study ap-peared to perceive less pain and feel more vital following12 weeks of exposure to a functional exereise circuit. Fi-nally, a reduction in the numher of doctor visits wouldseem to go hand in hand witb improved mobility as wellas a reduction in pain and a feeling of more vitality. Otherinvestigators have reported that older adults who reporta high level of physical functioning also perceived them-selves as heing healthy (21). Hence, such subjects are lessapt to make scheduled visits to their doctor.

This study offers support for using a functional exer-

cise circuit as a safe and cost-effective alternative to tra-ditional exercise interventions for older adults. Suhjectsdid appear to derive hoth functional and perceived healthbenefits from their participation in the functional exercisecircuit. Clearly, these finding must be interpreted withcaution. Without an experimental investigation, we maynot conclude a cause-and-efTect relationship. However,considering the adherence rate of 83% and the faet thatno subjects sustained injury during the course of thestudy, the functional exercise circuit did appear to besuitahle for older adults. Future investigations should fo-cus on comparing a traditional exereise intervention withthe functional exercise circuit.

PRACTICAL APPLICATIONS

A practitioner may find that a functional exercise circuitcan be both challenging and beneficial for an elderly sub-ject wishing to improve physical functioning and mobility.In addition, hecause the functional exereise circuit in-cludes a series of movement patterns that must be pro-duced under varying conditions (i.e., spaee negotiations,directional changes, level changes), the subject is affordedcognitive stimulation. Still, it is unclear at this timewhether hetter results could be expected from a function-al exercise circuit like the one employed here when com-pared to traditional exercise interventions. Nevertheless,considering that none of the subjects in this study wasinjured and that the participation is both time- and cost-effective, it seems logical to consider a functional exercisecircuit an alternative form of exercise for older adults.

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AcknowledgmentsThis study was supported hy a grant from the QuantumFoundation, Inc., West Palm Beach, Florida.

Address correspondence to Dr. Michael Whitehurst,whitehur@fau.edu.