Evaluation of a Group Exercise Program for
Elderly Women
Louis R Amundsen Julie M DeVahl Corinne T Ellingham
The purpose of this study was to evaluate the physical training effect of a specific set of calisthenics performed by a supervised group of elderly women. The exercise program was designed to be performed by groups of subjects without using
expen-sive equipment, large gymnasiums, or outdoor facilities. Fourteen women with an average age of 75.7 years trained for eight weeks. Five women with an average age of 71.8 years served as the control group. Submaximal graded exercise toler-ance (GXT) step tests were performed before and after training. Significant decreases in submaximal GXT heart rate (HR), systolic blood pressure (SBP), and rate-pressure product (RPP) were observed in the exercise group. Predicted maxi-mal aerobic power (MAP) increased 12.4% in the exercise group. The control group demonstrated significant decreases for submaximal GXT SBP and RPP, but not for HR. Predicted MAP for the control group decreased 33%. We concluded that this particular training regimen could be used safely and effectively with elderly subjects. The decrease in submaximal GXT HR, SBP, and RPP and the increase in predicted MAP indicate that a training effect can be expected when this exercise regimen is performed by sedentary elderly women. [Amundsen LR, DeVahl ]M, Ellingham CT Evaluation of a group exercise program for elderly women.
Phys Ther 69:475-483, 1989]
Key Words: Aging; Cardiac, tests and measurements; Exercise, general; Heart rate.
Ample intuitive and scientific informa tion indicates that physical perfor mance decreases as age increases. For example, cross-sectional studies indi cate that aerobic power decreases at the rate of 0.40 to 0.45 mL
O2.kg-1.min-1 per year, and longitu dinal studies have found a decrease of 1.0 mL O2.kg-1.min-1 per year.1 Active individuals, however, show less decrease in aerobic power (cardiopul
monary endurance) and skeletal mus cle strength than sedentary indivi duals.2-4 A relatively slow rate of decline in physical performance is likely when malnutrition, disease, genetic defects, and hypokinetic life styles are eliminated or minimized.5,6 Given these circumstances, we are likely to observe minimal perform ance deficits up to the age of 85 years and perhaps higher.5 Certainly, evi
dence exists that performance deficits are minimal in active individuals up to the age of 65 years.7 After age 65 to 75 years, a combination of factors typ ically occurs to contribute to a more rapid rate of decline. These factors are a sedentary life style, the effects of aging, and the cumulative effects of chronic health problems. Further study is needed to more clearly describe the rate of decline in physi cal performance and the trainability of persons over the age of 75 years. Most research concerning the effec tiveness of exercise for counteracting the ill effects of a hypokinetic life style on cardiopulmonary function has been conducted on relatively young individuals. In the past, it was custom ary to classify anyone over 55 or 60 years of age as "old." In addition, pre-L Amundsen, PhD, PT, is Director and Assistant Professor, Graduate Studies in Physical Therapy,
Department of Medicine and Rehabilitation, University of Minnesota, PO Box 388 UMHC, Minneap olis, MN 55455 (USA).
J DeVahl, MS, PT, is Marketing Clinical Therapist, Medtronic, Incorporated, 6951 Central Ave NE, PO Box 1250, Minneapolis, MN 55440. She was a student in the master's degree program in physi cal therapy, University of Minnesota, when this study was conducted.
C Ellingham, MS, PT, is Assistant Professor, Physical Therapy Program, Department of Physical Med icine and Rehabilitation, University of Minnesota.
This article was submitted June 15, 1988; was with the authors for revision for 12 weeks; and was accepted January 27, 1989.
vious studies have been limited by restricting the types of exercises to jogging, treadmill exercise, or bicycle ergometer exercise. Given the rapidly increasing number of elderly individ uals, the need for inexpensive exer cise in this population will continue to expand. Information on the effec tiveness of exercises that can be per formed by groups of elderly subjects without expensive equipment, large gymnasiums, or outdoor facilities is critical. The purpose of this study was to evaluate the physical training effect of a specific set of calisthenics per formed by a supervised group of elderly women. We hypothesized that eight weeks of physical training with the specific set of calisthenics would result in decreases in heart rate (HR), systolic blood pressure (SBP), and rate-pressure product (RPP) (SBP × HR) responses to given submaximal work rates and to increases in pre dicted maximal aerobic power (MAP). Review off Literature
Repetitive physical exercise using the lower extremities or a muscle mass greater than one-seventh of the total muscle mass has been demonstrated to be effective for physical training when performed at appropriate inten sities and durations by healthy young and middle-aged adults and by patients with cardiac disease.8-17 Recently, several reviews and recom mendations for physical training pro grams for the elderly have been published.1,6,18-20 The consensus is that exercise for the elderly is feasible and is likely to be effective for improving cardiopulmonary endur ance. The evidence, however, should be examined carefully before making inferences concerning the effective ness of specific programs.
Most physical training programs evolved from theories or programs originally developed for middle-aged individuals at risk for cardiac disease or from specific cardiac rehabilitation programs. For example, Adams and
deVries studied the effectiveness of 12 weeks of calisthenics, walking-jogging, and muscle stretching performed for 60 minutes, three times per week.21 Seventeen women with an average age of 65.9 years participated in the physical training program, and 6 women with an average age of 66.7 years who did not participate in the training program constituted the con trol group. All subjects were evaluated during pretraining and posttraining sessions. They used a bicycle ergome ter to perform submaximal graded exercise tolerance (GXT) tests that included the monitoring of HR, pul monary ventilation, and oxygen uptake (Vo2). The physical work capacity (watts achieved on the GXT tests) increased significantly for the trained subjects but not for the con trol subjects. Training resulted in greater efficiency of cardiovascular responses to the GXT tests. Trained subjects consistently demonstrated greater decreases in HR responses (pretraining minus posttraining val ues) to each submaximal work rate of the GXT tests than the untrained con trol group subjects. After training, however, the Vo2 at 85% of the pre dicted maximal HR measured at the final stage of the GXT tests was not significantly different between the trained group and the control group. Blood pressures were not reported for GXT test results.
Because previous investigators had shown little or no increase in aerobic power as a result of low- to moder ate-intensity physical training of the elderly, Seals et al conducted a study of the effects of low- and high-inten sity training.22 Low-intensity training consisted of continuous walking for 20 to 30 minutes at least three times per week and encouragement to increase general daily activity. High-intensity training consisted of a 10- to 15-minute warm-up period of muscle stretching and slow walking followed by 30 to 45 minutes of endurance exercise at a HR of 75% of HR reserve. This endurance exercise con
sisted of level walking progressed to jogging, bicycle ergometer exercise, or graded treadmill walking. Pretrain ing and posttraining GXT tests were conducted on a treadmill using the Bruce protocol. Physiological criteria were used to determine Vo2. Eleven subjects (7 men, 4 women) aged 62 ± 2 years, completed the training, which consisted of six months of low-intensity training followed by six months of high-intensity training. A statistically significant increase in Vo2 occurred after low-intensity training (0.8 MET,* p < .05) and again after high-intensity training (1.34 METs,
p < .01). Overall, the subjects' Vo2 increased 2.14 METs, from an average of 7.26 to 9.4 METs. One MET is the average Vo2 during rest in a sitting position.
The elderly subjects of the studies of Adams and deVries21 and Seals et al22 were relatively young. Obviously, a need exists for studies of subjects older than the average ages of 65.9 and 62 years of the studies by Adams and deVries21 and Seals et al,22 respectively. Other studies of older subjects have not demonstrated a training effect for the cardiopul monary system,23-25 have not tested for a cardiopulmonary training effect,26-27 or have used training meth ods that require unreasonably large gymnasiums or expensive equipment (bicycle ergometers or treadmills).28,29 Even though existing scientific evi dence, general reviews, and feasibility studies indicate that physical training is likely to be beneficial for elderly subjects, the effectiveness of specific exercise programs still needs to be demonstrated for specific populations of elderly subjects. A large number of people currently live in high-rise apartments reserved for the elderly. These residents have unique needs for physical training, and these build ings almost always have space that can easily be used for group exercise. This space has usually been set aside for meetings, dining, recreational activities, or parties. Exercise rooms equipped with stationary bicycles, bicycle ergometers, treadmills, and other exercise equipment are not *1 MET (metabolic equivalent) = 3.5 mL O2.kg-1.min-1
unusual. Even well-equipped exercise rooms, however, almost never entice or allow large numbers of residents to train at appropriate intensities with optimal routines. The ability of the people living in these buildings to travel to off-site exercise programs or even to walk outside is often limited by subclinical cardiopulmonary dis ease, orthopedic problems, obesity, chronic pain, metabolic disorders, vision and hearing impairments, and environmental hazards. Environmental hazards could include snow and ice, cold or hot weather, busy street cross ings, or high-crime areas. The advan tages of group exercise offered at the high-rise apartment appear obvious. Ideally, all exercise programs and rec ommendations should be evaluated prior to routine or general implemen tation. Studies of the effectiveness of specific convenient and inexpensive group exercise programs for residents of apartments reserved for the elderly are needed.
Method
Subjects
Volunteers from a high-rise apartment complex supervised by the Minneapo lis Housing Authority served as sub jects for the study. The protocol for testing and training was presented to each subject in written format as a component of the consent form and verbally by one of the investigators (CTE). The project was approved by the University of Minnesota Commit tee on the Use of Human Subjects. All subjects completed a preliminary screening that consisted of the review of a medical history form, a resting single-lead electrocardiogram, and resting blood pressure and HR. An electrocardiograph,† consisting of an ECG monitor, oscilloscope, and HR meter, and a Gould strip chart recorder* were used to obtain the ECGs. Subjects were not tested if the
resting ECG showed abnormalities not previously documented and cleared by the attending physician. The ECG was considered abnormal if any of the following were present: premature ventricular contractions exceeding six per minute, ST-segment depression or elevation greater than 1 mm 0.08 second after the J point, ventricular or atrial arrhythmias, or bundle branch blocks. Subjects were not tested if the resting HR exceeded 100 beats per minute (bpm), the SBP exceeded 200 mm Hg, or the diastolic blood pressure exceeded 110 mm Hg.
Procedure
Both the preliminary screening and the pretest were scheduled for one visit. Testing or training was termi nated or delayed pending a physi cian's approval if the preliminary screening or further testing appeared to be abnormal. Measurements of height and weight were obtained for all subjects.
Following these measurements, car diopulmonary fitness was assessed by a submaximal GXT test. All subjects were then invited to participate in an eight-week group exercise program. After the training period, all subjects who completed the pretest were invited to participate in the posttest. Subjects who completed the pretest and the posttest, but were unable to attend exercise classes because of conflicts in their schedules, served as the control group.
Graded Exercise Tolerance Test
The submaximal GXT test used in this study involved a stepping ergometer designed for testing elderly or seden tary subjects.30-34 The step heights and cadences are described in Table 1. Heart rate and ECG readings were constantly displayed during the GXT test. Electrocardiographic tracings were recorded routinely during the
last 20 seconds of each exercise stage. Blood pressure was measured as soon after each exercise stage as possible. Delay time for BP measurement was estimated to be 15 to 20 seconds. The GXT test consisted of stepping in the pattern shown in Figure 1 at a constant frequency of 20 mounts per minute and 80 counts per minute for three minutes at each stage of the test and progressively increasing the height of stepping for additional test stages. The following test protocol was established: 1) Stage 1—level stepping, 2) Stage 2—stepping up and down on a 4-in§ platform, 3) Stage 3—stepping up and down on an 8-in platform, and 4) Stage 4—stepping up and down on a 12-in platform. The test was terminated if the HR
exceeded 75% of its range, symptoms or signs of exercise intolerance were observed, or special precautions needed to be followed because of a medical history of arthritis or severe cardiopulmonary disease. For conve nience, target HR ranges for the GXT test were selected from Table 2.8,9 The GXT test was terminated at a tar get HR of at least 60% but not greater than 75% of the age-predicted HR range. The test was terminated earlier if the following objective signs of exercise intolerance were observed or reported: 1) the ECG results were abnormal, 2) the SBP exceeded 225 mm Hg, 3) the diastolic blood pres sure exceeded 130 mm Hg, or 4) the
T a b l e 1 . Step Test Heights and Cadences for Graded Exercise Tolerance Testing Height (ina) 0 4 8 12 Stepping Frequency (METsb) 20/min 2.0 3.4 4.7 6.1 30/min 2.8 4.5 7.0 9.5 a1 in = 2.54 cm.
b1 MET (metabolic equivalent) = 3.5 mL O2 .kg- 1 .min- 1.
†Model PM 2A, Electronics for Medicine, 30 Virginia Rd, White Plains, NY 10603. ‡Model 220, Gould Inc, 3631 Perkins Ave, Cleveland, OH 44114.
§1 in = 2.54 cm.
SBP decreased more than 20 mm Hg. The GXT test was also terminated if the subject asked to stop or reported or demonstrated shortness of breath; chest, neck, jaw, or arm pain; back, hip, knee, or ankle pain; dizziness, nausea, or confusion; general fatigue or fatigue of the lower extremities; or sudden pallor or inappropriate
sweating.30,35 Tests were not pro
gressed to target HRs if the medical history included reports of significant joint pain (especially in the hips or knees), a diagnosis of significant car diopulmonary disease, severe osteoporosis, or a rate of increase in the HR that indicated the target HR would be significantly exceeded on the next stage of the test.
Each three-minute exercise stage was followed by a one-minute pause to allow the measurement of BP without extraneous noise from stepping. The one-minute pause also allowed time to position the appropriate stepping platform. Standing BP was measured immediately after the subject stopped stepping. Blood pressure was mea sured noninvasively using a standard stethoscope and aneroid gauge sphyg momanometer. One investigator (LRA) measured all BPs.
Training Regimen
The physical training consisted of group exercise supervised by a licensed physical therapist (JMD). For mal exercise sessions were held twice per week, and subjects were encour aged to exercise with a partner one additional session per week. Subjects were taught to monitor their own pulse rate and to exercise within a target HR zone. The target HR zone was established on the basis of the pretraining GXT test. Because of the submaximal design of the GXT test, the training HR zone was set at a range starting 10 bpm below the highest asymptomatic HR and pro gressing only as high as 75% of the age-predicted maximal HR range. The target HR range, however, was never set higher than the highest asymptom atic HR observed on the pretraining GXT test. Name tags labeled with the target HR were used during all group
exercise sessions to facilitate the mon itoring of exercise intensity.
A calisthenics program was designed to exercise all major muscle groups of the body (Figs. 2, 3). Exercises 1 to 5 were designed to allow a gradual warm-up and to improve local muscle endurance (Fig. 2). Exercises 6 to 8 were designed primarily to promote cardiopulmonary endurance and sec ondarily to improve lower extremity local muscle endurance (Fig. 3). Exer cises 9 to 12 were designed primarily to promote flexibility and to provide a supervised "cool-down" period.
During each session, subjects moni tored and reported HR prior to start ing exercise 1, before starting exer cise 6, after completing exercise 8, and at the end of the session. The exercises were progressive as shown in Table 3. This progression was designed to accommodate the most adaptive or the most fit subjects. Sub jects were instructed to add rest peri ods or to bend their knees less for exercises 6 to 8, when HR exceeded the target range, or when any pain or unusual fatigue was experienced. Exercise 1 and exercises 3 to 5 were regulated primarily by the resistance
Fig. 1 . Stepping pattern for graded exercise tolerance testing.
T a b l e 2 . Age-related Target Heart Rate (HR) Ranges for Submaximal Graded
Exer-cise Tolerance Testing (in Beats per Minute)8,9
Age (yr) 20-30 31-40 41-50 51-60 61-70 71-80 81-90 Predicted Maximal HRa 200-190 189-180 179-170 169-160 159-150 149-140 139-130 Recommended Target HRb 138-165 132-157 126-149 120-142 114-134 108-127 102-119
a220 minus subject's age (in years).
bCalculated using Karvonen's formula: target HR = resting HR + [0.60-0.75(HR range)]; HR range = predicted maximal HR - resting HR; resting HR = 60 bpm.
given by the partner, rather than by intermittent rest periods. All exercises were performed to music, which assisted in pacing and added variety to the program.
Data Analysis
All statistical analyses were performed on a personal computer with a statisti cal analysis package." Means and stan dard deviations were calculated for all subjects for physiological measure ments. We performed t tests for related measures to test for changes in submaximal GXT HR, SBP, and RPP over the training period for the exer cise and control groups.
Identical work rates for submaximal GXT test responses were compared for pretest versus posttest results. For example, if the highest work rate achieved on the pretest was 3.4 METs, comparisons were calculated for responses to 3.4 METs on the posttest, even if the subject was capable of pro gressing to the 4.7-MET level. In addi tion, predicted MAPs recorded before and after training were compared using the t test for related measures. Predicted MAP was calculated using the following formula15,36:
Predicted Map = GXT MET
141 (GXT HR/age-predicted HR) - 42 where GXT MET is the highest MET level performed on the GXT test, GXT HR is the HR recorded at GXT MET, and age-predicted HR is 220 minus the subject's age (in years).
The highest achieved MET levels on the pretest and posttest were used to calculate the predicted MAP. Percent ages of change were also calculated to allow a convenient quantification of direction and magnitude of change over the training period for the exer cise and control groups. Measure ments of secondary interest (age, height, and weight) were reported only as descriptive statistics.
Fig. 2. Exercises for physical training: Warm-up and local muscle endurance (exer-cises 1-5), cardiopulmonary fitness (exer(exer-cises 6-8), and muscle stretching and "cool-down" exercises (exercises 9-12).
Results
Initially, 36 elderly residents from a high-rise apartment supervised by the Minneapolis Housing Authority volun teered for the exercise program. No subjects were eliminated because of resting ECG, HR, or blood pressure abnormalities during the preliminary screening. The medical history screening procedure eliminated two subjects from the study because of
their inability to perform the step test. Five female subjects who participated in both the pretest and the posttest, but were unable to attend exercise sessions because of other commit ments during the time scheduled for group sessions, served as the control group. Fifteen subjects were elimi nated from the study because they attended fewer than half of the group sessions. Fourteen female subjects constituted the exercise group. These subjects rarely performed the recom mended third session per week. Demographic data for all exercise ║NH Analytical Software, 1958 Eldridge Ave, Roseville, MN 55113.
T a b l e 3 . Exercise Program Progression Week 1 2 3 4 5 6 7 8
Warm-up and Local Muscle Endurance Exercises (1-5) Repetitionsa Durationb 5 10 15 20 25 30 30 30 3 5 6 7 8 8 8 8 Cardiopulmonary Endur-ance Exercises (6-8) Cyclec Duration 1 2 3 4 5 6 7 8 5 8 11 14 17 20 23 26
"Cool-down" and Muscle Stretching Exercises (9-12) Repetitionsd Duration 1 1 2 3 3 3 3 3 3 5 6 6 6 6 6 6 Total Duration 11 18 23 27 31 34 37 40
group and control group subjects are shown in Table 4.
The GXT tests were stopped at Stage 1 for six subjects at Stage 2 for two subjects because they achieved their target HR. The GXT test was stopped at Stage 2 for one subject because she complained of shortness of breath. Extra precautions necessitated by a history of painful hips or knees sec ondary to arthritis, heart disease, pul monary disease, implantation of a fixed-rate pacemaker, or severe osteoporosis caused us to terminate the GXT test of six subjects after Stage 1 and three subjects after Stage 2. One subject's GXT test was stopped after Stage 2 because her HR rate of increase between Stage 1 and Stage 2 was considered to be excessive.
Statistically significant decreases
(p < .05) were observed after train ing for resting SBP and RPP and for submaximal GXT HR, SBP, and RPP for the exercise group (Tab. 5). Pre dicted MAP increased 12.4% after training for the exercise group, but this increase was not statistically sig nificant. Resting HR and RPP did not change significantly for the control group; however, the resting SBP did decrease significantly on the posttest
for the control group. Submaximal GXT HR did not decrease over the training period for the control group; however, submaximal GXT SBP did decrease significantly on the posttest for the control group.
Discussion
For the experimental group, all physi ological variables changed in the direction that indicated a training effect. Physical training is expected to improve the efficiency of the cardio vascular and respiratory systems. The observed decreases in submaximal GXT HR, SBP, and RPP are indicative of improved efficiency of cardiovascu
lar adjustments required for oxygen delivery and utilization. Heart rate, SBP, and RPP responses to known submaximal work rates are readily-available objective quantitative mea sures. When these tests are performed as a component of pretraining and posttraining assessments, the effective ness of the treatment for an individual patient or group of patients can readily be determined. Given that all of these measures decreased signifi cantly in our study, we would logi cally conclude that training was effec tive for our exercise group. Other studies of the effectiveness of physical training on the elderly have appar ently not reported the statistical
signif-T a b l e 4 . Characteristics of Subjects Variable Age (yr) Height (ina) Weight (lbb) Group Exercise (n = 14) 75.7 61.1 139.2 s 7.3 3.1 31.2 Control (n = 5) 71.8 61.6 135.3 s 9.7 2.0 27.3
aRepetitions per minute.
bDuration = total time (in minutes) allowed for the phase.
cOne cycle consisted of 30 to 60 seconds of stepping (80 steps per minute) for each component of exercises 6 to 8. dEach repetition held for 5 seconds at week 1 and 10 seconds at weeks 2 to 8.
a1 in = 2.54 cm. 1 lb = 0.4536 kg.
T a b l e 5 . Means and Standard Deviations, Paired t-Test Results, and Percentages of Change for Pretraining Versus Posttraining
Comparisons for Exercise and Control Groups
Group and Independent Variablea Exercise group (n = 14) Resting HRc SBP RPPc Exercised METs HRc SBP RPPc MAP Control group (n = 5) Resting HR SBP RPP Exercised METs HR SBP RPP MAP Pretest 74.9 153.4 11.5 2.6 102.9 160.4 16.6 4.5 87.1 145.6 12.6 2.3 110.6 143.2 15.8 3.7 s 10.6 20.9 2.2 0.7 13.1 25.9 3.6 1.7 10.4 17.0 1.7 0.6 16.1 12.9 2.8 0.8 Posttest 72.1 142.6 10.2 2.6 97.4 147.6 14.3 5.1 90.1 128.4 11.5 2.3 110.9 134.0 14.9 3.6 s 8.9 19.3 1.5 0.7 13.2 20.1 2.8 2.1 6.6 10.2 0.9 0.6 9.5 12.1 2.2 0.7 t 2.01 2.42 3.17 2.51 2.44 3.58 1.44 0.63 4.92 1.64 0.09 3.94 2.27 0.58 Pb .07 .03 .01 .03 .03 .00 .18 .56 .01 .18 .93 .02 .08 .60 % - 3 . 7 -7.1 -11.3 - 5 . 3 - 8 . 0 -13.9 12.4 3.4 -11.8 - 8 . 8 0.2 -6.4 - 6 . 0 - 3 . 3
icance of these changes. Indeed, it appears that only Adams and deVries even mentioned these changes at repeated submaximal levels.21 The relative magnitude of the change in RPP (-13.9%) in our study is in agreement with the changes reported by May and Nagle (-14.87%) for patients with coronary artery disease.11
The control group was analyzed to evaluate the effects of familiarization with the testing procedure. Any novel experience is likely to cause slight increases in HR and SBP. It is also possible that the practice will result in greater mechanical efficiency in the performance of the step test. The sig nificant decrease in GXT SBP in the control group could be due to either
of these reasons. Novelty or anxiety, however, will increase HR as much as or more than SBP and cause relatively greater increases during the resting measurements, which are taken dur ing the peak of anticipation, than dur ing exercise. Because the HR responses of the control group did not decrease on the posttraining step test, an increase in mechanical effi ciency or psychological adaptation to circumstances perceived to be novel, exciting, or threatening is not likely to have caused the observed decreases in SBP. Other explanations for the decreases in SBP are possible. A high percentage of the subjects were taking medication to control high blood pressure. Random or systematic changes in the length of time between ingestion of medication and
testing could have occurred for con trol subjects between the pretest and the posttest. The relatively small num ber of subjects in the control group would make it more sensitive to these possible changes. No subjects, how ever, reported changes in dosage or types of medication at the posttest review of the medical history.
The method used for predicting MAP needs to be discussed. Obviously, the prediction of a hypothetical maximal value from different submaximal vari ables is likely to introduce systematic or random error. An inspection of the formula used for predicting MAP indi cates that two submaximal measured values and one value estimated by age are required. The actual measurement of HR from ECG strips obtained dur-aHR = heart rate (bpm); SBP = systolic blood pressure (mm Hg); RPP = rate-pressure product (bpm.mm Hg.103); METs = highest exercise work rate,
expressed in metabolic equivalents (one MET = 3.5 mL O2.kg-1.min-1); MAP = maximum aerobic power calculated from submaximal responses,
expressed in METs.
bp < .05 for the two-tailed paired t test.
cSubject with a fixed-rate pacemaker not included.
ing the step test is not likely to intro duce significant error. Heart rate, which was constantly displayed on the HR meter, appeared to be quite stable during the last 20 seconds of each exercise stage; aging has been shown to decrease the variability of HR dur ing the respiratory cycle.37 The MET levels for this step test were estab lished from data obtained on young adults rather than older adults; how ever, oxygen cost is not likely to change with age unless the mechani cal work of stepping is altered by fac tors indirectly related to aging. The factors that could alter the pattern of stepping include osteoarthritis, mal alignment related to healed hip frac tures, cerebrovascular insufficiency, and peripheral nerve involvement. Obvious failure to follow the prescribed stepping cadence and pat tern was not present in either the experimental group or the control group.
Estimates of MAP should be used pri marily for comparing pretraining and posttraining or treatment performance for the same subject or for gross fit ness classifications. Ideally, predicted MAP values should be used for inter-group comparisons only if end points and GXT test protocols are identical. Comparisons between values obtained from different protocols should be made with caution, because each method of predicting MAP is likely to contain specific characteristics that introduce subtle differences into the calculated MAP. For example, differ ences between MAPs measured with different modes of exercise have been documented, but these differences have been determined to have mini mal practical implications. The results of tests conducted with a bicycle ergometer, treadmill, or step test yield comparable results for young healthy subjects and for patients with cardiac disease unless the subject has obvious problems with the performance of the test.16 Additionally, the advantages of predicting MAP from submaximal val ues rather than establishing MAP from volitional maximal work rates must be noted. Volitional maximal values are likely to introduce error unless strin gent criteria are used to document
that MAP was actually measured. The MAP can be documented objectively, for example, if the following criteria are met: 1) Vo2 no longer increases when work rate is increased, 2) exer cise HR equals or exceeds the age-predicted maximal HR, 3) the respira tory exchange ratio (Vco2/Vo2) exceeds 1.15, and 4) blood lactate four minutes after exercise is at least 8 mmol per liter of blood.22 The diffi culties and dangers of routinely fol lowing these guidelines when testing the elderly appear obvious.
Our MAP values can be compared with values obtained in other studies. Morse and Smith reported MAP values of 5 to 7 METs for 65- to 75-year-olds and 2 to 4 METs for ambulatory nurs ing home residents.38 They deter mined volitional maximal values with treadmill tests. Even though their pre vious work had demonstrated the fea sibility of maximal tests for the elderly, Sidney and Shephard consid ered it prudent not to attempt maxi mal tests on elderly, sedentary volun teers for a study of the effects of physical training.28,39 The average MAP they predicted from the submaximal bicycle ergometer tests of their 60- to 83-year-old subjects was 6.12 METs. The average age was not reported, but this preretirement fitness training group is likely to approximate an average age of 65 years. Thompson et al performed symptom-limited tests for MAP using the Balke treadmill protocol on a sample of 58 people, 64 to 83 years of age.24 Four subjects had positive test results (eg, ST-segment depression) and were eliminated from the study, 3 were unable to walk on the treadmill, and 10 exceeded the arbitrary upper limit of 8.1 METs. The average MAP (5.5 METs) was reported only for the subjects who completed the study (n = 21). This value is simi lar to our exercise group's mean pre test and posttest predicted MAP values of 4.5 and 5.1 METs, respectively. Our subjects could be classified as having average to low fitness for their respec tive age group.
Even though elderly subjects have demonstrated a training effect from intensities as low as 40% to 50% of
the HR range, we used a training intensity goal of 60% to 75% and modified this target HR range accord ing to the results of the pretest GXT. The average percentages of the HR range achieved on the GXT test were 51.8% for the exercise group and 57.2% for the control group. When expressed simply as a percentage of age-predicted maximal HR, these val ues were 72.0% for the exercise group and 74.4% for the control group. Each subject was assigned a minimum and a maximum target HR for training. The minimum and maxi mum values averaged 94.6 and 101.5 bpm, respectively. The average train ing HR was 41.4% to 50.1% of the available HR range. When expressed as a simple percentage of the age-predicted maximal HR, the percent ages were 66.0% to 71.0%
Even with these apparently conserva tive target HRs, we were more likely to have difficulty reaching than exceeding the target HR. Amundsen et al, however, demonstrated that exercise HRs reported by the subjects tend to be lower than HRs measured by the exercise leaders.30 Subjects tend to count accurately but to be slower to locate the pulse and to begin counting after exercise has ceased. Nevertheless, further study of similar subjects using higher target HRs appears to be advisable to explore the possibility of obtaining greater and statistically significant gains in predicted MAP. Despite the absence of statistically significant gains and because of the relatively small number of subjects in our study, our observed percentage of increase in MAP (12.4%) after eight weeks of training compares favorably with the gain observed (12%) for the six months of low-intensity training used by Seals et al.22
Conclusion
The results suggest that this particular training regimen, which consists of calisthenics that require very little space and no equipment other than common straight-back chairs and pos sibly background music, can be applied to groups of elderly subjects
safely and productively. The decrease in submaximal HR, SBP, and RPP, and the increase in predicted MAP indi cate that a training effect can be expected from this or similar physical exercise training protocols performed by elderly subjects.
References
1 Stamford BA: Exercise and the elderly. In Pandolf KB (ed): Exercise and Sports Reviews. New York, NY, Macmillan Publishing Co, 1988, vol 16, pp 341-379
2 Dehn MM, Bruce RA: Longitudinal variations in maximal oxygen intake with age and activ ity. J Appl Physiol 33:805-807, 1972
3 Drinkwater BL, Horvath SM, Wells CL: Aero bic power of females, ages 10 to 68. J Geron tol 30:385-394, 1975
4 Aniansson A, Sperling L, Rundgren A, et al: Muscle function in 75-year-old men and women: A longitudinal study. Scand J Rehabil Med [Suppl] 9:92-102, 1983
5 Fries JF, Crapo LM: Vitality and Aging: Impli cations of the Rectangular Curve. San Fran cisco, CA, W H Freeman & Co Publishers, 1981, pp 1-9, 25-40
6 Grimby G: Physical activity and muscle train ing in the elderly. Acta Med Scand [Suppl] 711: 233-237, 1986
7 Shephard RJ: Gross changes in form and function. In Shephard RJ (ed): Physical Activity and Aging. Chicago, IL, Year Book Medical Publishers Inc, 1978, pp 52-145
8 Karvonen MJ, Kentala E, Mustala O: The effects of training on heart rate. Annales Medicinae Experimentatus et Biologie Fenniae 35:307-315, 1958
9 Amundsen LR: Establishing activity and train ing levels for patients with ischemic heart dis ease. Phys Ther 59:754-758, 1979
10 Carter CL: Cardiac rehabilitation of outpa tients during the recovery phase following myocardial infarction. In Amundsen LR (ed): Cardiac Rehabilitation: Clinics in Physical Ther apy. New York, NY, Churchill Livingstone Inc, 1981, pp 111-119
11 May GA, Nagle FJ: Changes in rate-pressure product with physical training of individuals with coronary artery disease. Phys Ther 64: 1361-1366, 1984
12 Stippig J, Berg A, Keul J: Medical and phys iological aspects. In Amundsen LR (ed): Car diac Rehabilitation: Outpatient Physical Train
ing Methods. Rockville, MD, Aspen Publishers Inc, 1988, pp 3-6
13 Graf RS: Rehabilitation during the acute and convalescent stages following myocardial infarction. In Amundsen LR (ed): Cardiac Reha bilitation: Clinics in Physical Therapy. New York, NY, Churchill Livingstone Inc, 1981, pp 99-109
14 Hagberg JM, Ehsani AA, Holloszy JO: Effect of 12 months of intense exercise training on stroke volume in patients with coronary heart disease. Circulation 67:1194-1199, 1983 15 Hellerstein HK, Hirsch EL, Adler R, et al: Principles of exercise prescription for normals and cardiac subjects. In Naughton J, et al (eds): Exercise Testing and Exercise Training in Cor onary Heart Disease. New York, NY, Academic Press Inc, 1973, pp 129-167
16 Shephard RJ, Allen C, Benade AJ, et al: The maximum oxygen intake. Bull WHO 38:757-764, 1968
17 Blomquist CG, Saltin B: Cardiovascular adaptations to physical training. Annu Rev Physiol 45:169-189, 1983
18 Vallbona C, Baker SB: Physical fitness pros pects in the elderly. Arch Phys Med Rehabil 65: 194-200, 1984
19 Payton OD, Poland JL: Aging process: Implications for clinical practice. Phys Ther 63: 41-48, 1983
20 Frontera WR, Evans WJ: Exercise perfor mance and endurance training in the elderly. Topics in Geriatric Rehabilitation 2:17-32, 1986
21 Adams GM, deVries HA: Physiological effects of an exercise training regimen upon women aged 52 to 79. J Gerontol 28:50-55,
1973
22 Seals DR, Hagberg JM, Hurley BF, et al: Endurance training in older men and women: I. Cardiovascular responses to exercise. J Appl Physiol: Respirat Environ Exercise Physiol 57: 1024-1029, 1984
23 Benestad AM: Trainability of old men. Acta Med Scand 178:321-327, 1965
24 Thompson RF, Crist DM, Marsh M, et al: Effects of physical exercise for elderly patients with physical impairments. J Am Geriatr Soc 36:130-135, 1988
25 Gutman GM, Herbert CP, Brown SR: Fel-denkrais versus conventional exercises for elderly. J Gerontol 32:562-572, 1977 26 Smith EL, Reddan W, Smith PE: Physical activity and calcium modalities for bone min eral increase in aged women. Med Sci Sports Exerc 13:60-64, 1981
27 Frekany GA, Leslie DK: Effects of exercise program on selected flexibility measurements
of senior citizens. Gerontologist 15:182-183, 1975
28 Sidney KH, Shephard RJ: Frequency and intensity of exercise training for elderly sub jects. Med Sci Sports 10:125-131, 1978 29 Barry AJ, Daly JW, Pruett ED, et al: The effects of physical conditioning on older indi viduals. I. Work capacity, circulatory-respira tory function, and work electrocardiogram. J Gerontol 21:182-191, 1966
30 Amundsen LR, Ellingham CT, Eliason ML, et al: Cardiac considerations and physical train ing. In Jackson O (ed): Physical Therapy of the Geriatric Patient: Clinics in Physical Therapy. New York, NY, Churchill Livingstone Inc, 1983, pp 181-201
31 Amundsen LR, Ellingham CT: Cardiac con siderations and physical training. In Jackson O (ed): Physical Therapy of the Geriatric Patient: Clinics in Physical Therapy, ed 2. New York, NY, Churchill Livingstone Inc, to be published 32 Nielsen DH, Amundsen LR: Exercise physi ology: An overview with emphasis on aerobic capacity and energy cost. In Amundsen LR (ed): Cardiac Rehabilitation: Clinics in Physical Therapy. New York, NY, Churchill Livingstone Inc, 1981, pp 11-28
33 Amundsen LR, Ellingham CT, Shore S: Car diopulmonary Fitness Test. Abstract. Cardiopul monary Record 2(3):13, 1987
34 Amundsen LR, Ellingham CT: Safe and effective exercise for the elderly. In: First World Congress on Allied Health, Abstracts— Access to Quality Health Care for All: The Pro vision of Human Resources. Elsinore, Den mark, June 14-17, 1988
35 Amundsen LR: Assessing exercise toler ance: A review. Phys Ther 59:534-537, 1979 36 Patterson RP: Home computer based per formance evaluation. In: Proceedings of the Twentieth Annual Rocky Mountain Bioengi-neering Symposium and the Twentieth Inter national ISA Biomedical Sciences Instrumenta tion Symposium. Rochester, MN, April 18-19, 1983, pp 77-81
37 Hrushesky WJM, Fader D, Schmitt O, et al: The respiratory sinus arrhythmia: A measure of cardiac age. Science 224:1001-1004, 1984 38 Morse CE, Smith EL: Physical activity pro gramming for the aged. In Smith EL, Serfass RC (eds): Aging and Exercise. Hillsdale, NJ, Enslow Publishers, 1981, pp 109-129 39 Sidney KH, Shephard RJ: Maximum and submaximum exercise tests in men and women in the seventh, eighth, and ninth dec ades of life. J Appl Physiol 43:280-287, 1977
