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Exercise Patterns in a Population of Older Adults
Exercise Patterns in a Population of Older Adults Janice B. McPhillips, MS, Karyn M. Pellettera, BS, Elizabeth Barrett-Connor, MD, Deborah L. Wingard, PhD, and Michael H. Criqui, MD, MPH
Little is known about the extent to which older adults engage in exercise, despite recent enthusiasm for exercise among people of all ages. This report describes the exercise patterns in a well-defined population of older adults living in southern California. From 1984 through 1987, we asked 1,140 members of a previously defined adult community 50-93 years of age to report the frequency and duration of participation in 14 leisure-time activities in the two weeks preceding a physical examination. Exercises were categorized as light, moderate, or heavy according to a previously validated scale. Interviewers ascertained information on chronic disease history, cigarette smoking, physical and emotional functioning, and self-rated health. More than 90% of the group reported some physical activity in the two-week period before their evaluation. While the rates of moderate and heavy exercise decreased with age, rates of participation in and duration of light exercise actually increased. Walking was the most common form of exercise reported and was positively associated with other exercise: walkers were more likely to engage in nearly every form of exercise ascertained by the questionnaire than were nonwalkers. Of those who walked or engaged in moderate or heavy exercise, nearly 60% did so three times a week for at least 20 minutes a time. Exercise frequency was lower in those with a history of chronic disease, obesity, or current cigarette smoking, and exercise was positively associated with physical and emotional functioning and self-rated health. These data illustrate that older adults can and do exercise late into life. While self-selection cannot be excluded, these data also support the hypothesis that exercise promotes well-being in older adults. [Am J Prev Med 1989;2:65-72)
The 1980's brought a surge of enthusiasm for the probable benefits of exercise in terms of improved health, quality of life, and reduction of risk for cardiovascular diseases. 1 - 6 As the population ages, the possibility that these benefits can be extended to the elderly is becoming a compelling public health issue,7- 9 although few data on exercise behavior among or benefits to older adults exist. We report on the exercise patterns of a large, free-living population of older men and women. METHODS
The study participants were part of an ongoing population-based study designed to examine lifeFrom the Division of Epidemiology, Department of Community and Family Medicine (McPhillips, Pellettera, Barrett-Connor, Wingard, and Criqui), and the Department of Medicine (Criqui), School of Medicine, University of California, San Diego, La Jolla, California. Address reprint requests to Dr. Barrett-Connor, Department of Community and Family Medicine, M-007, University of California, San Diego, La Jolla, CA 92093
style and chronic disease in older adults. 10 All residents of Rancho Bernardo, California, who were between 40 and 84 years of age at the time of the initial study (1972-74) were invited to participate in the study (1984-87), and 81 % did so. As part of this evaluation, they completed a self-administered exercise questionnaire that ascertained the frequency and duration with which they participated in 14 different leisure-time activities during the two-week period before their clinic visit. The questionnaire, adapted from the 1985 Health Interview Survey, can be found in the Appendix. 11 For analysis, activities were grouped on the basis of relative intensity, modified from the intensity codes established and validated by the Minnesota Heart Survey: 1, 12 light (gardening, dancing, calisthenics, golf, bowling, horse riding, and walking); moderate (hiking, tennis, bicycling, and swimming); and heavy (jogging, handball, and aerobic dance). Participation in other activities was not considered at length. Those participants who reported a minimum of 20 minutes of aerobic activity at least three times a week were considered to meet the American Heart Am
J Prev Med 1989;51'2 65
Association (AHA) guidelines for attaining enhanced cardiovascular fitness. 13 As defined by the AHA, aerobic activity includes any moderate or heavy activity and may include walking provided that the walker achieves a heart rate that is at least 60%-75% of his or her maximum heart rate. The self-administered exercise questionnaire was given to all subjects seen from May 1985 through March 1987. Trained interviewers obtained data on the number of city blocks walked per day (assuming 12 city blocks per mile), participation in organized exercise programs, and current or previous cigarette smoking. The participants answered standardized questions about a personal history of chronic diseases, including heart attack, intermittent claudication, hypertension, stroke, cancer, and diabetes. They were asked to rate themselves as "minimally limited," "moderately limited," or "severely limited" with respect to their physical and emotional functioning in the month before their visit and to rate their overall health as "better," "the same," or "worse" relative to others their own age. We measured the participants' height and weight in light clothing without shoes; obesity was defined as a body mass index (weight/height2) greater than or equal to 26 kg/m 2 . We computed participants' walking velocity by dividing the number of miles walked per day by the length of time (in hours) walked per session. Because these two pieces of information were obtained with different instruments at different times in the visit-the former interviewer-administered and the latter self-reported-they provide only crude measures of velocity and are used here for
comparison between men and women rather than as true values . We computed the mean number of hours of exercise, including 0 hours for subjects who reported no exercise . We assessed the differences in mean hours of exercise with Student's ttest. We age-adjusted the rates by the direct method (using the entire sample as the standard) and tested the differences in age-adjusted rates using the Mantel-Haenszel summary chi-square with one degree of freedom.14 RESULTS
The age- and sex-specific distribution of light, moderate, and heavy exercise for the 1,140 men and women 50-93 years of age is shown in Table 1. The mean age was 66.5 years for men and 67.0 years for women (P = .42). With the exception of those who reported no exercise (6.5% of all men and 11.8% of all women), the exercise patterns of men and women were very similar. Light activity was more common than moderate and heavy exercise combined: 87.9% of men and women reported light activity, 28.0% reported moderate activity, and 6.8% reported heavy activity. The rates of light activity reported remained relatively constant with increasing age, while participation in moderate and heavy activities declined. The number of hours of participation in light and moderate activities increased with age through the age of 79, especially among men (Table 2). The rates of participation in and mean hours of light activity were somewhat lower in the fall and winter months, while the rates of participation in and hours of moderate and heavy activity did not vary by season (unpublished obser-
Table 1. Age- and sex-specific and age-adjusted rates of exercise by relative intensity levels
Age (years) Men 50-59 60-69 70-79 ~so
Total Age-adjusted rate Women 50-59 60-69 70-79 ~so
Total Age-adjusted rate
N
Light exercise % n
143 179 124 62 50S
130 162 llS 52 462
90.9 90.5 95.2 S3.9 90.9 91.0
17S 197 171 S6 632
151 171 145 73 540
84.S S6.S 84.S 84.9 S5.4 S5.5
Moderate exercise % n 49 56 3S 10
153
5S 64
34 10
166
66 American journal of Preventive Medicine, volume 5, number 2
Heavy exercise % n
34.3 31.3 30.6 16.1 30.1 30.0
23 11 7 1
32.6 32.5 19.9 11.6 26.3 26.5
20 12
42
4
16.1 6.1 5.6 1.6 .3 .2 11.2 6.1
_.J
0
5.7 5.
Table 2. A&e- and sex-specific mean hours of exercise over a two-week period by relative mtensity levels
Age (years) Men (n = 508) 50-59 60-69 70-79 ~80
Total Women (n = 632) 50-59 60-69 70-79 ~80
Total
Light exercise Mean± SD
Moderate exercise Mean± SD
Heavy exercise Mean± SD
10.9 14.3 19.0 9.1 13.9
± ± ± ± ±
14.9 14.8 16.0 10.5 15.0
1.1 1.4 1.5 0.9 1.3
± ± ± ± ±
2.5 3.4 4.3 3.8 3.5
0.7 0.1 0.2 0.0 0.3
± ± ± ± ±
2.3 0.6 1.1 0.1 1.4
8.1 9.9 10.2 6.2 9.0
± ± ± ± ±
11.0 11.5 11.8 6.2 10.9
0.8 1.2 0.6 0.2 0.8
± ± ± ± ±
1.8 3.2 1.6 0.7 2.2
0.3 0.3 0.1 0.0 0.2
± ± ± ± ±
1.6 1.5 0.7 0.0 1.2
vations). Some individuals participated in more than one level of activity. However, the majority of those who reported light activity (64.3% of men and 68.5% of women) engaged only in light activity. Participation in only light activity increased with age in both men and women: 57.3% of 50 to 59year-old men and women who engaged in light activity did not report moderate or heavy activities, and 83.2% of men and women 80 years of age or older did not report any moderate or heavy activities. Considered together, 34.6% of men and 29.4% of women of all ages participated in moderate or heavy activities. The rates of participation in either moderate or heavy activities were slightly higher among men than among women at all ages and declined with age in both sexes. Only eight men and 44 women, or 4.6% of the group, reported participation in organized exercise programs. The activities most frequently reported by both men and women were walking (n = 695, 61.0%), gardening (n = 662, 58.1 %), calisthenics (n = 300, 26.3% ), and golf (n = 248, 21.8%) (Table 3). The specific exercises men and women engaged in were similar except for those who did heavy exercise: more men reported jogging than women (7.2% and 1.6%, respectively, P < .001), and women reported more aerobic dance than men (4.7% and 0.4%, respectively, P < .001). The number of hours of walking, swimming, and bicycling was positively correlated with age (r = .08, P = .02 for walking; r = .18, P = .02 for swimming; r = .18, P = .02 for bicycling). Only 116 (10.2%) men and women reported engaging in other activities. The most commonly reported activities among those who reported other activities were housecleaning (n = 23, 19.8%), heavy household projects such as painting
(n = 11, 9.5%), rowing on a rowing machine (n = 10, 8.6%), and lawn bowling (n = 8, 6.9%). Walking was the most common form of exercise reported. Those who walked did so an average of nearly eight times every two weeks for at least 30 minutes each time (Table 4). Among women, the number of hours walked and the frequency of walking increased with age (hours walked: r = .10, P = .04; frequency of walking: r = .12, P = .02). In men, the frequency of walking increased with age
Table 3. Age-adjusted sex-specific rates of participation in fourteen activities
Activity Light Walking Gardening Calisthenics Golf Dancing Bowling Horse riding
Women (n = 632) Men (n = 508) Rate(%) Rate(%) n n
12 3
62.0 66.5* 25.2 28.1* 8.7 2.4 0.8
381 323 172 106 69 18 3
60.2 51.1 27.1 17.0 11.0 2.9 0.3
Moderate Swimming Bicycling Hiking Tennis
65 57 29 28
12.8 11.3 5.7 5.4**
73 72 20 16
11.7 11.5 3.2 2.6
Heavy Jogging Aerobic dance Handball
37 2 4
7.2* 0.4* 0.8
10 29 0
1.6 4.7 0
314 339 128 142 44
Statistically significant difference between men and women based on Mantel-Haenszel chi-square statistic with one degree of freedom. • P ~ .05 . •• p ~ .001.
Am j Prev Med 1989 ;51'2 6
·eported walking
Table 4. Age- and sex-specific walking activity over
Age (years) Men 50- 59 60-69 70-79
;.so
Total Women 50-59 60-69 70-79
;.so
Total
Walking Frequency (Walks per 2 weeks)
n
6.5 S.3
Duration (Minutes per - .,.
Distance 'Blocks per day)
= 14.2 = 11.5 i.- =11 .9 - .0 =12.5 i.--.. =11 .S i.- = 10.0 .- =11.7 -=.3 = 10.2
9.1 7.9
:!:: :!:: :!:: :!:: :!::
4.3 5.5 4.9 9.1 5.7
33.S 35.3 33.2 30.9 33.S
:!:: :!:: :!:: :!:: :!::
20.S 24.1 24.5 36.S 25.3
7.2 7.5 S.1 9.0 7.S
:!:: :!:: :!:: :!:: :!::
5.7 5.5 5.4 4.S 5.5
34.S 35.3 34.4 31.5 34.4
:!:: :!:: :!:: :!:: :!::
19.S 2S.2 2S.6 18.3 25.0
79 107 SS 40 314
s.o
104 117 107 53 3Sl
(r = .13, P = .02), although there was no consistent trend in the number of hours walked and age. Men reported walking significantly faster and farther than women: men walked 2.5 miles an hour compared to 2.0 miles per hour for women (P = .01), and men walked an average of 10.0 city blocks a day compared to 7.9 for women (P = .003). Walking was not a substitute for other exercise in these older adults. Those who reported walking also reported engaging in other activities of all intensity levels
Table 5. Age-adjusted rates of participation in other activities among walkers and nonwalkers Walkers (n
Activity Light Gardening Calisthenics Golf Dancing Bowling Horse riding Moderate Swimming Bicycling Hiking Tennis Heavy Jogging Aerobic dance Handball
Nonwalkers
= 695)
(n
= 445)
n
(%)
n
(%)
433 212 152 Sl 17 2
(62.3) (30.4) (21.5) (11.6) (2.5) (0.3)
229 SS 32 13 4
(51.2)* (19.S)* (21.8) (7.2)** (2.9) (0.9)
8S 77 46 32
(12.7) (11 .2) (6.8) (4.S)
50 52 3 12
(11.3) (11.6) (0.6)* (2.6)
33 25 1
(4.9) (3.7) (0.2)
14 6 3
96
(3.0) (1 .3)** (0.7)
Statistically significant difference between walkers and nonwalkers based on Mantel-Haenszel chi-square statistic with one degree of freedom. • p ,,;;; .05. •• p ,,;;; .001.
~.o
± 11.3
:~. 5
.: 3
3.9 4.0 4.6 4.9 4.3
=3.: =3./ :!:: :!:: :!::
4.5
4.4 3.9
7.
= 11.0
with greater frequency than those who did not report walking (Table 5). Overall, th e majority of those who walked (89.2% of men and 84.3% of women) reported engaging in at least one other activity in the two weeks before the visit. Aside from walking, the other most frequently reported activity for both men and women was gardening. Men who gardened spent an average of 8.9 hours gardening during the previous two weeks, while women who gardened spent an average of 5.3 hours (P = .0005). Calisthenics and golf were two other frequently reported activities. Over the two week period, on the average, men and women who did calisthenics or golfed spent in excess of 2 hours doing calisthenics and almost 15 hours golfing. Those who reported no exercise at all made up 9.5% of the total. These nonexercisers were slightly older and significantly more overweight than exercisers (68.3 and 66.6 years, P = .10; body mass indexes of 29.1 and 25.4 kg/m 2 , P = .003). Current cigarette smoking and a history of stroke, heart attack, high blood pressure, and diabetes were all more common among the nonexercisers than among those who reported any exercise, although none of these differences was statistically significant (unpublished observations). Of the 816 men and women who engaged in moderate or heavy exercise or walking, 59.4% did so at least three times a week for a minimum of 20 minutes each time and thereby met the AHA guidelines in terms of frequency and duration of exercise for the two weeks before their clinic visit. Table 6 shows the age- and sex-specific proportion of all men and w omen wh o met the AHA guidelines (without regard to achieved heart rate, which was
68 American journal of Preventive Medicine, volume 5, number 2
Table 6. Age-adjusted rates of meeting American Heart Association (AHA) guidelines according to chronic disease, obesity, and cigarette smoking status Age-adjusted percentage meeting AHA guidelines
a
Chronic disease
Obesity
Smoking
Age (years)
n
Yes
No"
Obese
Non obese"
Current
Past
Never"
Men 50-69 70-93
322 186
43.1 49.3
42.1 49.6
41.5 41.2
41.8 53.8
21.1 ** 33.3*
43.9 45.7*
48.0 64.0
Women 50-69 70-93
375 257
44.1 26.7*
43.6 43 .8
32.2* 20.6*
47.0 41.7
30.8 21.5
48.7 39.8
44.0 38.8
Statistically significant differences from reference group based on Mantel-Haenszel chi-square statistic with one degree of freedom . Reference group.
p.;; .05 . •• p.;; .01.
not ascertained) by chronic disease, obesity, and smoking status. Over 40% of all men and women below the age of 70 years met the AHA guidelines whether or not they reported one or more chronic diseases. Significantly fewer women who were 70 years of age or older at the time of their visit and who also had one or more chronic diseases met the AHA guidelines than did those 70 years of age or older without a history of chronic disease (P < .05). Significantly more nonobese women met the AHA exercise guidelines than did overweight women (P < .05), but there was no significant difference in exercise status between leaner and fatter men. Fewer women who were current smokers met the
AHA guidelines than former or never smokers, though none of these differences was statistically significant. In younger and older men there was a trend for increasing exercise according to nonsmoking status, and most of these comparisons were statistically significant. The mean cumulative hours of exercise in the preceding two weeks according to self-assessment of health relative to others their own age and physical and emotional functioning in the month prior to the visit are presented in Table 7. Overall, those who felt better about their health and physical and emotional functioning exercised more than those who did not, although the comparisons were consis-
Table 7. Mean cumulative hours of exercise over a two-week period according to health and physical and emotional functioning
Question
n
Hours of light" exercise (mean)
Compared to others your own age, how would you rate your health? Group 1: Better/same Group 2: Worseb
1,096 42
11.4** 6.0
1.0 0.8
0.2 0.1
971 77
11.8*** 5.9
1.0* 0.6
0.3 0.2
1,059 34
11.6*** 6.1
1.0 0.7
0.2*** 0.0
How would you rate your physical functioning during the past month? Group 1: Minimally limited Group 2: Largely limitedb How would you rate your emotional functioning during the past month? Group 1: Minimally limited Group 2: Largely limitedb
• ••
Hours of moderate exercise (mean)
Hours of heavy exercise (mean)
Includes walking. Reference group .
p.;; .05. p.;; .01. ••• p.;; .001.
Am j Prev Med 7989; 5(2) 69
tently statistically significant only for number of hours of light exercise.
DISCUSSION In this cross-sectional study, the rate of participation in light exercise varied little with age while rates of moderate and heavy exercise decreased with age. Older participants who engaged in light exercises did so for longer periods of time than their younger counterparts. These increments with increasing age were especially pronounced among men and may reflect an increasing participation in leisure-time activities after retirement, as described by others. 15 The overall decrease in exercise activity with age observed in our study is consistent with previously reported results. 1,3,16,17 Although others such as the Minnesota Heart Survey, 1 Tecumseh Study, 16 and studies in Orange County, California, 3 and New England 17 have reported a decline in all leisure-time activities with age, increasing participation in light activities after the age of 45 has been observed in both Minnesota1 and Michigan. 16 The amount of walking reported by this cohort is impressive and possibly is due, in part, to the favorable year-round climate in southern California. Participation in golf, bicycling, and other outdoor activities is most likely greater than that observed elsewhere. However, despite the differing climate, walking also was reported as the primary form of exercise in older adults living in Seattle, Washington.18 It is noteworthy that walking was associated with other exercises in this cohort of active older adults. Those who walked were more likely to participate in other exercises ascertained by the questionnaire than were nonwalkers. The association between exercise and well-being has been explored in a variety of studies. There is evidence to suggest that exercise decreases depression and hostility in alcoholics, postmyocardial infarction patients, and other clinically depressed individuals .19 Among healthy clinic patients, a regimen of regular exercise reduced tension, depression, fatigue, and confusion as well as decreasing the number of doctor visits 20 and improving self-rated health. 21 The data from our study, while not prospective in nature, also illustrate a correlation between exercise and self-rated physical and psychological well-being. These data do not resolve the major conundrum of whether those who exercise more are initially healthier or whether exercise promotes well-being. In response
e- to que- • s a::- those who cave ~o-e clearly more act.-:e se \·.·ho gave less positive response . s~ . ar -• - 0 e with a history of chronic disease exercised !es than those without. This issue of self- election has plagued all studies of exercise and health to date, both cross-sectional, as here, and prospective. 22 This study is based on self-reported leisure-time exercise of residents from an upper-middle-class and health-conscious California community. Although an overestimate of the reported amount or type of exercise cannot be excluded, several lines of evidence suggest that self-reports are generally valid. First, the foregoing reported exercise correlated highly with response to a general question, "Do you regularly engage in strenuous exercise or hard physical labor?" The latter question has been shown to be correlated with treadmill exercise capacity. 23 Almost 60% of those who engaged in moderate or heavy activity answered the question affirmatively. Second, the amount and type of exercise is plausible for healthy adults in this age range. Finally, the cohort has given reliable self-reports about other more readily validated health behaviors. For example, their diet recall showed the expected correlations of mineral intake with measured blood pressure24 and weekly alcohol intake with aspartate aminotransferase. 25 The American public is increasingly health conscious, and this interest includes increased exercise and improved diet. 26 Patterns of exercise in Rancho Bernardo are almost surely better than those for many other North Americans of similar age who have neither the climate nor the exposure to the emphasis on health, fitness, and youth that pervades the southern California culture. Although not representative, these data do illustrate the potential for an exercise program resembling that recommended by the American Heart Association for the prevention of heart disease in adults at least up to the age of 80. Clearly, more exercise is possible at older ages than was previously thought. The longterm benefits of such programs are only beginning to be documented, 27 but impro\'ed vigor and selfsatisfaction with physical and mental health appear to be correlated with exercise among the elderly.
This work was supported by gra:-: :- .. -A..\'81801 from the National Institute of Diabetes , Dt::es~ :e and Kidney Diseases and a grant from the \.'\'eigh• •'a• ~ ;dation, Inc. The authors thank Cheryl Wuchi.-ia : - - -:ce in the preparation of this manuscript.
70 American journal of Preventive Medicine, volume 5, number 2
APPENDIX
In the past 14 days, have you done any of the following exercises, sports, or physically active hobbies?
1) 2) 3) 4) 5) 6) 7) 8) 9) 10)
11) 12) 13) 14) 15)
Walking for exercise? Jogging or running? Hiking? Gardening or yard work? Aerobics or aerobic dancing? Other dancing? Calisthenics or general exercise? Golf? Tennis? Bowling? Bicycle riding? Swimming or water exercises? Horseback riding? Handball, racquetball, or squash? Have you done any other exercises, sports, or physically active hobbies in the past 2 weeks other than the ones listed above? If yes, what were they?
Yes
No
D D D D D D D D D D D D D D
D D D D D D D D D D D D D D
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On the average, how many times in the past 14 days did you play/go/do: _ _ times _ _ times _ _ times _ _ times _ _ times _ _ times _ _ times _ _ times _ _ times _ _ times _ _ times _ _ times _ _ times _ _ times
About how many minutes did you actually spend on each occasion? _ _ minutes _ _ minutes _ _ minutes _ _ minutes _ _ minutes _ _ minutes _ _ minutes _ _ minutes _ _ minutes _ _ minutes _ _ minutes _ _ minutes _ _ minutes _ _ minutes
_ _ times _ _ times _ _ times
_ _ minutes _ _ minutes _ _ minutes
8. Paffenbarger RS, Hyde RT, Hsieh CC, et al. Physical activity, other life-style patterns, cardiovascular disease and longevity. Acta Med Scand 1986;71l(suppl):85-91. 9. Siscovick DS, Laporte RE, Newman JM. The diseasespecific benefits and risks of physical activity and exercise. Public Health Rep 1985;100:180-8. 10. Criqui MH, Barrett-Connor E, Austin M. Differences between respondents and non-respondents in a population-based cardiovascular disease study. Am J Epidemiol 1978;108:367- 72. 11. Moss AJ, Parsons VL. Current estimates from the National Health Interview Survey, United States, 1985. Washington, DC: National Center for Health Statistics, 1986; DHHS publication no. (PHS)86-1588. (Vital and Health Statistics; series 10; no. 160.) 12. Taylor HL, Jacobs DR, Schucker B, et al. A questionnaire for the assessment of leisure time activities. J Chronic Dis 1978;31:741-55. 13. American Heart Association. Exercise and your heart. Dallas: American Heart Association, 1984; AHA publication no. 51-053A. 14. Mantel N, Haenszel W. Statistical aspects of the analysis of data from retrospective studies of disease. J Natl Cancer Inst 1959;22:719-48. 15. Stephens T, Jacobs DR, White CG. A descriptive epi-
· Am j Prev Med 7989;5(2) 71
demiology of leisure-time physical activity. Public Health Rep 1985;100:147-58. 16. Cunningham DA, Montoye HJ, Metzner HL, et al. Active leisure time activities as related to age among males in a total population. J Gerontol 1968;23:551-6. 17. Zborowski M. Aging and recreation. J Gerontol 1962;17:302-9. 18. Perry BC. Exercise patterns of an elderly population. Am J Fam Pract 1982;15:545-6.
22. Siegel AJ, Henne ·ens c.: ~ history of coronary heart disease - ,. runners. N Engl J Med 1979;301:90- : . 23. Haskell WL, Taylor HL, Wood PD, et al. Srrenuous physical activity, treadmill exercise test performance and plasma high-density lipoprotein cholesterol. Circulation 1980;62(suppl 4):53-61. 24. Khaw KT, Barrett-Connor E. The association between blood pressure, age, and dietary sodium and potassium: a population study. Circulation 1988;77:53-61.
19. Taylor CB, Sallis JF, Needle R. The relation of physical activity and exercise to mental health. Public Health Rep 1985;100:195-202.
25. Barrett-Connor E, Suarez L. A community study of alcohol and other factors associated with the distribution of high density lipoprotein cholesterol in older vs. younger men. Am J Epidemiol 1982;115:88-93.
20. Stones MJ, Kozma A, Stones L. Fitness and health evaluations by older exercisers. Can J Public Health 1987;78:18-20.
26. Barrett-Connor E. Health promotion: proof of the pudding. Am J Prev Med 1987;3:2-ll.
21. Jylha M, Leskinen E, Alanen E, et al. Self-rated health and associated factors among men of different ages. J Gerontol 1986;6:710-17.
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72 American Journal of Preventive Medicine, volume 5, number 2
Little is known about the extent to which older adults engage in exercise, despite recent enthusiasm for exercise among people of all ages. This report describes the exercise patterns in a well-defined population of older adults living in southern California. From 1984 through 1987, we asked 1,140 members of a previously defined adult community 50-93 years of age to report the frequency and duration of participation in 14 leisure-time activities in the two weeks preceding a physical examination. Exercises were categorized as light, moderate, or heavy according to a previously validated scale. Interviewers ascertained information on chronic disease history, cigarette smoking, physical and emotional functioning, and self-rated health. More than 90% of the group reported some physical activity in the two-week period before their evaluation. While the rates of moderate and heavy exercise decreased with age, rates of participation in and duration of light exercise actually increased. Walking was the most common form of exercise reported and was positively associated with other exercise: walkers were more likely to engage in nearly every form of exercise ascertained by the questionnaire than were nonwalkers. Of those who walked or engaged in moderate or heavy exercise, nearly 60% did so three times a week for at least 20 minutes a time. Exercise frequency was lower in those with a history of chronic disease, obesity, or current cigarette smoking, and exercise was positively associated with physical and emotional functioning and self-rated health. These data illustrate that older adults can and do exercise late into life. While self-selection cannot be excluded, these data also support the hypothesis that exercise promotes well-being in older adults. [Am J Prev Med 1989;2:65-72)
The 1980's brought a surge of enthusiasm for the probable benefits of exercise in terms of improved health, quality of life, and reduction of risk for cardiovascular diseases. 1 - 6 As the population ages, the possibility that these benefits can be extended to the elderly is becoming a compelling public health issue,7- 9 although few data on exercise behavior among or benefits to older adults exist. We report on the exercise patterns of a large, free-living population of older men and women. METHODS
The study participants were part of an ongoing population-based study designed to examine lifeFrom the Division of Epidemiology, Department of Community and Family Medicine (McPhillips, Pellettera, Barrett-Connor, Wingard, and Criqui), and the Department of Medicine (Criqui), School of Medicine, University of California, San Diego, La Jolla, California. Address reprint requests to Dr. Barrett-Connor, Department of Community and Family Medicine, M-007, University of California, San Diego, La Jolla, CA 92093
style and chronic disease in older adults. 10 All residents of Rancho Bernardo, California, who were between 40 and 84 years of age at the time of the initial study (1972-74) were invited to participate in the study (1984-87), and 81 % did so. As part of this evaluation, they completed a self-administered exercise questionnaire that ascertained the frequency and duration with which they participated in 14 different leisure-time activities during the two-week period before their clinic visit. The questionnaire, adapted from the 1985 Health Interview Survey, can be found in the Appendix. 11 For analysis, activities were grouped on the basis of relative intensity, modified from the intensity codes established and validated by the Minnesota Heart Survey: 1, 12 light (gardening, dancing, calisthenics, golf, bowling, horse riding, and walking); moderate (hiking, tennis, bicycling, and swimming); and heavy (jogging, handball, and aerobic dance). Participation in other activities was not considered at length. Those participants who reported a minimum of 20 minutes of aerobic activity at least three times a week were considered to meet the American Heart Am
J Prev Med 1989;51'2 65
Association (AHA) guidelines for attaining enhanced cardiovascular fitness. 13 As defined by the AHA, aerobic activity includes any moderate or heavy activity and may include walking provided that the walker achieves a heart rate that is at least 60%-75% of his or her maximum heart rate. The self-administered exercise questionnaire was given to all subjects seen from May 1985 through March 1987. Trained interviewers obtained data on the number of city blocks walked per day (assuming 12 city blocks per mile), participation in organized exercise programs, and current or previous cigarette smoking. The participants answered standardized questions about a personal history of chronic diseases, including heart attack, intermittent claudication, hypertension, stroke, cancer, and diabetes. They were asked to rate themselves as "minimally limited," "moderately limited," or "severely limited" with respect to their physical and emotional functioning in the month before their visit and to rate their overall health as "better," "the same," or "worse" relative to others their own age. We measured the participants' height and weight in light clothing without shoes; obesity was defined as a body mass index (weight/height2) greater than or equal to 26 kg/m 2 . We computed participants' walking velocity by dividing the number of miles walked per day by the length of time (in hours) walked per session. Because these two pieces of information were obtained with different instruments at different times in the visit-the former interviewer-administered and the latter self-reported-they provide only crude measures of velocity and are used here for
comparison between men and women rather than as true values . We computed the mean number of hours of exercise, including 0 hours for subjects who reported no exercise . We assessed the differences in mean hours of exercise with Student's ttest. We age-adjusted the rates by the direct method (using the entire sample as the standard) and tested the differences in age-adjusted rates using the Mantel-Haenszel summary chi-square with one degree of freedom.14 RESULTS
The age- and sex-specific distribution of light, moderate, and heavy exercise for the 1,140 men and women 50-93 years of age is shown in Table 1. The mean age was 66.5 years for men and 67.0 years for women (P = .42). With the exception of those who reported no exercise (6.5% of all men and 11.8% of all women), the exercise patterns of men and women were very similar. Light activity was more common than moderate and heavy exercise combined: 87.9% of men and women reported light activity, 28.0% reported moderate activity, and 6.8% reported heavy activity. The rates of light activity reported remained relatively constant with increasing age, while participation in moderate and heavy activities declined. The number of hours of participation in light and moderate activities increased with age through the age of 79, especially among men (Table 2). The rates of participation in and mean hours of light activity were somewhat lower in the fall and winter months, while the rates of participation in and hours of moderate and heavy activity did not vary by season (unpublished obser-
Table 1. Age- and sex-specific and age-adjusted rates of exercise by relative intensity levels
Age (years) Men 50-59 60-69 70-79 ~so
Total Age-adjusted rate Women 50-59 60-69 70-79 ~so
Total Age-adjusted rate
N
Light exercise % n
143 179 124 62 50S
130 162 llS 52 462
90.9 90.5 95.2 S3.9 90.9 91.0
17S 197 171 S6 632
151 171 145 73 540
84.S S6.S 84.S 84.9 S5.4 S5.5
Moderate exercise % n 49 56 3S 10
153
5S 64
34 10
166
66 American journal of Preventive Medicine, volume 5, number 2
Heavy exercise % n
34.3 31.3 30.6 16.1 30.1 30.0
23 11 7 1
32.6 32.5 19.9 11.6 26.3 26.5
20 12
42
4
16.1 6.1 5.6 1.6 .3 .2 11.2 6.1
_.J
0
5.7 5.
Table 2. A&e- and sex-specific mean hours of exercise over a two-week period by relative mtensity levels
Age (years) Men (n = 508) 50-59 60-69 70-79 ~80
Total Women (n = 632) 50-59 60-69 70-79 ~80
Total
Light exercise Mean± SD
Moderate exercise Mean± SD
Heavy exercise Mean± SD
10.9 14.3 19.0 9.1 13.9
± ± ± ± ±
14.9 14.8 16.0 10.5 15.0
1.1 1.4 1.5 0.9 1.3
± ± ± ± ±
2.5 3.4 4.3 3.8 3.5
0.7 0.1 0.2 0.0 0.3
± ± ± ± ±
2.3 0.6 1.1 0.1 1.4
8.1 9.9 10.2 6.2 9.0
± ± ± ± ±
11.0 11.5 11.8 6.2 10.9
0.8 1.2 0.6 0.2 0.8
± ± ± ± ±
1.8 3.2 1.6 0.7 2.2
0.3 0.3 0.1 0.0 0.2
± ± ± ± ±
1.6 1.5 0.7 0.0 1.2
vations). Some individuals participated in more than one level of activity. However, the majority of those who reported light activity (64.3% of men and 68.5% of women) engaged only in light activity. Participation in only light activity increased with age in both men and women: 57.3% of 50 to 59year-old men and women who engaged in light activity did not report moderate or heavy activities, and 83.2% of men and women 80 years of age or older did not report any moderate or heavy activities. Considered together, 34.6% of men and 29.4% of women of all ages participated in moderate or heavy activities. The rates of participation in either moderate or heavy activities were slightly higher among men than among women at all ages and declined with age in both sexes. Only eight men and 44 women, or 4.6% of the group, reported participation in organized exercise programs. The activities most frequently reported by both men and women were walking (n = 695, 61.0%), gardening (n = 662, 58.1 %), calisthenics (n = 300, 26.3% ), and golf (n = 248, 21.8%) (Table 3). The specific exercises men and women engaged in were similar except for those who did heavy exercise: more men reported jogging than women (7.2% and 1.6%, respectively, P < .001), and women reported more aerobic dance than men (4.7% and 0.4%, respectively, P < .001). The number of hours of walking, swimming, and bicycling was positively correlated with age (r = .08, P = .02 for walking; r = .18, P = .02 for swimming; r = .18, P = .02 for bicycling). Only 116 (10.2%) men and women reported engaging in other activities. The most commonly reported activities among those who reported other activities were housecleaning (n = 23, 19.8%), heavy household projects such as painting
(n = 11, 9.5%), rowing on a rowing machine (n = 10, 8.6%), and lawn bowling (n = 8, 6.9%). Walking was the most common form of exercise reported. Those who walked did so an average of nearly eight times every two weeks for at least 30 minutes each time (Table 4). Among women, the number of hours walked and the frequency of walking increased with age (hours walked: r = .10, P = .04; frequency of walking: r = .12, P = .02). In men, the frequency of walking increased with age
Table 3. Age-adjusted sex-specific rates of participation in fourteen activities
Activity Light Walking Gardening Calisthenics Golf Dancing Bowling Horse riding
Women (n = 632) Men (n = 508) Rate(%) Rate(%) n n
12 3
62.0 66.5* 25.2 28.1* 8.7 2.4 0.8
381 323 172 106 69 18 3
60.2 51.1 27.1 17.0 11.0 2.9 0.3
Moderate Swimming Bicycling Hiking Tennis
65 57 29 28
12.8 11.3 5.7 5.4**
73 72 20 16
11.7 11.5 3.2 2.6
Heavy Jogging Aerobic dance Handball
37 2 4
7.2* 0.4* 0.8
10 29 0
1.6 4.7 0
314 339 128 142 44
Statistically significant difference between men and women based on Mantel-Haenszel chi-square statistic with one degree of freedom. • P ~ .05 . •• p ~ .001.
Am j Prev Med 1989 ;51'2 6
·eported walking
Table 4. Age- and sex-specific walking activity over
Age (years) Men 50- 59 60-69 70-79
;.so
Total Women 50-59 60-69 70-79
;.so
Total
Walking Frequency (Walks per 2 weeks)
n
6.5 S.3
Duration (Minutes per - .,.
Distance 'Blocks per day)
= 14.2 = 11.5 i.- =11 .9 - .0 =12.5 i.--.. =11 .S i.- = 10.0 .- =11.7 -=.3 = 10.2
9.1 7.9
:!:: :!:: :!:: :!:: :!::
4.3 5.5 4.9 9.1 5.7
33.S 35.3 33.2 30.9 33.S
:!:: :!:: :!:: :!:: :!::
20.S 24.1 24.5 36.S 25.3
7.2 7.5 S.1 9.0 7.S
:!:: :!:: :!:: :!:: :!::
5.7 5.5 5.4 4.S 5.5
34.S 35.3 34.4 31.5 34.4
:!:: :!:: :!:: :!:: :!::
19.S 2S.2 2S.6 18.3 25.0
79 107 SS 40 314
s.o
104 117 107 53 3Sl
(r = .13, P = .02), although there was no consistent trend in the number of hours walked and age. Men reported walking significantly faster and farther than women: men walked 2.5 miles an hour compared to 2.0 miles per hour for women (P = .01), and men walked an average of 10.0 city blocks a day compared to 7.9 for women (P = .003). Walking was not a substitute for other exercise in these older adults. Those who reported walking also reported engaging in other activities of all intensity levels
Table 5. Age-adjusted rates of participation in other activities among walkers and nonwalkers Walkers (n
Activity Light Gardening Calisthenics Golf Dancing Bowling Horse riding Moderate Swimming Bicycling Hiking Tennis Heavy Jogging Aerobic dance Handball
Nonwalkers
= 695)
(n
= 445)
n
(%)
n
(%)
433 212 152 Sl 17 2
(62.3) (30.4) (21.5) (11.6) (2.5) (0.3)
229 SS 32 13 4
(51.2)* (19.S)* (21.8) (7.2)** (2.9) (0.9)
8S 77 46 32
(12.7) (11 .2) (6.8) (4.S)
50 52 3 12
(11.3) (11.6) (0.6)* (2.6)
33 25 1
(4.9) (3.7) (0.2)
14 6 3
96
(3.0) (1 .3)** (0.7)
Statistically significant difference between walkers and nonwalkers based on Mantel-Haenszel chi-square statistic with one degree of freedom. • p ,,;;; .05. •• p ,,;;; .001.
~.o
± 11.3
:~. 5
.: 3
3.9 4.0 4.6 4.9 4.3
=3.: =3./ :!:: :!:: :!::
4.5
4.4 3.9
7.
= 11.0
with greater frequency than those who did not report walking (Table 5). Overall, th e majority of those who walked (89.2% of men and 84.3% of women) reported engaging in at least one other activity in the two weeks before the visit. Aside from walking, the other most frequently reported activity for both men and women was gardening. Men who gardened spent an average of 8.9 hours gardening during the previous two weeks, while women who gardened spent an average of 5.3 hours (P = .0005). Calisthenics and golf were two other frequently reported activities. Over the two week period, on the average, men and women who did calisthenics or golfed spent in excess of 2 hours doing calisthenics and almost 15 hours golfing. Those who reported no exercise at all made up 9.5% of the total. These nonexercisers were slightly older and significantly more overweight than exercisers (68.3 and 66.6 years, P = .10; body mass indexes of 29.1 and 25.4 kg/m 2 , P = .003). Current cigarette smoking and a history of stroke, heart attack, high blood pressure, and diabetes were all more common among the nonexercisers than among those who reported any exercise, although none of these differences was statistically significant (unpublished observations). Of the 816 men and women who engaged in moderate or heavy exercise or walking, 59.4% did so at least three times a week for a minimum of 20 minutes each time and thereby met the AHA guidelines in terms of frequency and duration of exercise for the two weeks before their clinic visit. Table 6 shows the age- and sex-specific proportion of all men and w omen wh o met the AHA guidelines (without regard to achieved heart rate, which was
68 American journal of Preventive Medicine, volume 5, number 2
Table 6. Age-adjusted rates of meeting American Heart Association (AHA) guidelines according to chronic disease, obesity, and cigarette smoking status Age-adjusted percentage meeting AHA guidelines
a
Chronic disease
Obesity
Smoking
Age (years)
n
Yes
No"
Obese
Non obese"
Current
Past
Never"
Men 50-69 70-93
322 186
43.1 49.3
42.1 49.6
41.5 41.2
41.8 53.8
21.1 ** 33.3*
43.9 45.7*
48.0 64.0
Women 50-69 70-93
375 257
44.1 26.7*
43.6 43 .8
32.2* 20.6*
47.0 41.7
30.8 21.5
48.7 39.8
44.0 38.8
Statistically significant differences from reference group based on Mantel-Haenszel chi-square statistic with one degree of freedom . Reference group.
p.;; .05 . •• p.;; .01.
not ascertained) by chronic disease, obesity, and smoking status. Over 40% of all men and women below the age of 70 years met the AHA guidelines whether or not they reported one or more chronic diseases. Significantly fewer women who were 70 years of age or older at the time of their visit and who also had one or more chronic diseases met the AHA guidelines than did those 70 years of age or older without a history of chronic disease (P < .05). Significantly more nonobese women met the AHA exercise guidelines than did overweight women (P < .05), but there was no significant difference in exercise status between leaner and fatter men. Fewer women who were current smokers met the
AHA guidelines than former or never smokers, though none of these differences was statistically significant. In younger and older men there was a trend for increasing exercise according to nonsmoking status, and most of these comparisons were statistically significant. The mean cumulative hours of exercise in the preceding two weeks according to self-assessment of health relative to others their own age and physical and emotional functioning in the month prior to the visit are presented in Table 7. Overall, those who felt better about their health and physical and emotional functioning exercised more than those who did not, although the comparisons were consis-
Table 7. Mean cumulative hours of exercise over a two-week period according to health and physical and emotional functioning
Question
n
Hours of light" exercise (mean)
Compared to others your own age, how would you rate your health? Group 1: Better/same Group 2: Worseb
1,096 42
11.4** 6.0
1.0 0.8
0.2 0.1
971 77
11.8*** 5.9
1.0* 0.6
0.3 0.2
1,059 34
11.6*** 6.1
1.0 0.7
0.2*** 0.0
How would you rate your physical functioning during the past month? Group 1: Minimally limited Group 2: Largely limitedb How would you rate your emotional functioning during the past month? Group 1: Minimally limited Group 2: Largely limitedb
• ••
Hours of moderate exercise (mean)
Hours of heavy exercise (mean)
Includes walking. Reference group .
p.;; .05. p.;; .01. ••• p.;; .001.
Am j Prev Med 7989; 5(2) 69
tently statistically significant only for number of hours of light exercise.
DISCUSSION In this cross-sectional study, the rate of participation in light exercise varied little with age while rates of moderate and heavy exercise decreased with age. Older participants who engaged in light exercises did so for longer periods of time than their younger counterparts. These increments with increasing age were especially pronounced among men and may reflect an increasing participation in leisure-time activities after retirement, as described by others. 15 The overall decrease in exercise activity with age observed in our study is consistent with previously reported results. 1,3,16,17 Although others such as the Minnesota Heart Survey, 1 Tecumseh Study, 16 and studies in Orange County, California, 3 and New England 17 have reported a decline in all leisure-time activities with age, increasing participation in light activities after the age of 45 has been observed in both Minnesota1 and Michigan. 16 The amount of walking reported by this cohort is impressive and possibly is due, in part, to the favorable year-round climate in southern California. Participation in golf, bicycling, and other outdoor activities is most likely greater than that observed elsewhere. However, despite the differing climate, walking also was reported as the primary form of exercise in older adults living in Seattle, Washington.18 It is noteworthy that walking was associated with other exercises in this cohort of active older adults. Those who walked were more likely to participate in other exercises ascertained by the questionnaire than were nonwalkers. The association between exercise and well-being has been explored in a variety of studies. There is evidence to suggest that exercise decreases depression and hostility in alcoholics, postmyocardial infarction patients, and other clinically depressed individuals .19 Among healthy clinic patients, a regimen of regular exercise reduced tension, depression, fatigue, and confusion as well as decreasing the number of doctor visits 20 and improving self-rated health. 21 The data from our study, while not prospective in nature, also illustrate a correlation between exercise and self-rated physical and psychological well-being. These data do not resolve the major conundrum of whether those who exercise more are initially healthier or whether exercise promotes well-being. In response
e- to que- • s a::- those who cave ~o-e clearly more act.-:e se \·.·ho gave less positive response . s~ . ar -• - 0 e with a history of chronic disease exercised !es than those without. This issue of self- election has plagued all studies of exercise and health to date, both cross-sectional, as here, and prospective. 22 This study is based on self-reported leisure-time exercise of residents from an upper-middle-class and health-conscious California community. Although an overestimate of the reported amount or type of exercise cannot be excluded, several lines of evidence suggest that self-reports are generally valid. First, the foregoing reported exercise correlated highly with response to a general question, "Do you regularly engage in strenuous exercise or hard physical labor?" The latter question has been shown to be correlated with treadmill exercise capacity. 23 Almost 60% of those who engaged in moderate or heavy activity answered the question affirmatively. Second, the amount and type of exercise is plausible for healthy adults in this age range. Finally, the cohort has given reliable self-reports about other more readily validated health behaviors. For example, their diet recall showed the expected correlations of mineral intake with measured blood pressure24 and weekly alcohol intake with aspartate aminotransferase. 25 The American public is increasingly health conscious, and this interest includes increased exercise and improved diet. 26 Patterns of exercise in Rancho Bernardo are almost surely better than those for many other North Americans of similar age who have neither the climate nor the exposure to the emphasis on health, fitness, and youth that pervades the southern California culture. Although not representative, these data do illustrate the potential for an exercise program resembling that recommended by the American Heart Association for the prevention of heart disease in adults at least up to the age of 80. Clearly, more exercise is possible at older ages than was previously thought. The longterm benefits of such programs are only beginning to be documented, 27 but impro\'ed vigor and selfsatisfaction with physical and mental health appear to be correlated with exercise among the elderly.
This work was supported by gra:-: :- .. -A..\'81801 from the National Institute of Diabetes , Dt::es~ :e and Kidney Diseases and a grant from the \.'\'eigh• •'a• ~ ;dation, Inc. The authors thank Cheryl Wuchi.-ia : - - -:ce in the preparation of this manuscript.
70 American journal of Preventive Medicine, volume 5, number 2
APPENDIX
In the past 14 days, have you done any of the following exercises, sports, or physically active hobbies?
1) 2) 3) 4) 5) 6) 7) 8) 9) 10)
11) 12) 13) 14) 15)
Walking for exercise? Jogging or running? Hiking? Gardening or yard work? Aerobics or aerobic dancing? Other dancing? Calisthenics or general exercise? Golf? Tennis? Bowling? Bicycle riding? Swimming or water exercises? Horseback riding? Handball, racquetball, or squash? Have you done any other exercises, sports, or physically active hobbies in the past 2 weeks other than the ones listed above? If yes, what were they?
Yes
No
D D D D D D D D D D D D D D
D D D D D D D D D D D D D D
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On the average, how many times in the past 14 days did you play/go/do: _ _ times _ _ times _ _ times _ _ times _ _ times _ _ times _ _ times _ _ times _ _ times _ _ times _ _ times _ _ times _ _ times _ _ times
About how many minutes did you actually spend on each occasion? _ _ minutes _ _ minutes _ _ minutes _ _ minutes _ _ minutes _ _ minutes _ _ minutes _ _ minutes _ _ minutes _ _ minutes _ _ minutes _ _ minutes _ _ minutes _ _ minutes
_ _ times _ _ times _ _ times
_ _ minutes _ _ minutes _ _ minutes
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· Am j Prev Med 7989;5(2) 71
demiology of leisure-time physical activity. Public Health Rep 1985;100:147-58. 16. Cunningham DA, Montoye HJ, Metzner HL, et al. Active leisure time activities as related to age among males in a total population. J Gerontol 1968;23:551-6. 17. Zborowski M. Aging and recreation. J Gerontol 1962;17:302-9. 18. Perry BC. Exercise patterns of an elderly population. Am J Fam Pract 1982;15:545-6.
22. Siegel AJ, Henne ·ens c.: ~ history of coronary heart disease - ,. runners. N Engl J Med 1979;301:90- : . 23. Haskell WL, Taylor HL, Wood PD, et al. Srrenuous physical activity, treadmill exercise test performance and plasma high-density lipoprotein cholesterol. Circulation 1980;62(suppl 4):53-61. 24. Khaw KT, Barrett-Connor E. The association between blood pressure, age, and dietary sodium and potassium: a population study. Circulation 1988;77:53-61.
19. Taylor CB, Sallis JF, Needle R. The relation of physical activity and exercise to mental health. Public Health Rep 1985;100:195-202.
25. Barrett-Connor E, Suarez L. A community study of alcohol and other factors associated with the distribution of high density lipoprotein cholesterol in older vs. younger men. Am J Epidemiol 1982;115:88-93.
20. Stones MJ, Kozma A, Stones L. Fitness and health evaluations by older exercisers. Can J Public Health 1987;78:18-20.
26. Barrett-Connor E. Health promotion: proof of the pudding. Am J Prev Med 1987;3:2-ll.
21. Jylha M, Leskinen E, Alanen E, et al. Self-rated health and associated factors among men of different ages. J Gerontol 1986;6:710-17.
27. Donohue RP, Abbott RD, Reed DR, et al. Physical activity and coronary heart disease in middle-aged and elderly men: the Honolulu Heart Program. Am J Public Health 1988;78:683-5.
72 American Journal of Preventive Medicine, volume 5, number 2