Muscular strength and physical function.

PURPOSE: The purpose of this study was to evaluate the potential association of muscular strength and endurance at baseline with the prevalence of functional limitations at follow-up. METHODS: Study participants were 3,069 men and 589 women (30-82 yr) who received a clinical examination including a strength evaluation at the Cooper Clinic between 1980 and 1989 and responded to a 1990 mail-back survey. Participants also had to achieve at least 85% of their age-predicted maximal heart rate on a maximal exercise treadmill test and have no history of heart attack, stroke, diabetes, high blood pressure, cancer, or arthritis at their first visit. A strength index composite score (0-6) was calculated using age- and sex-specific tertiles from bench press, leg press, and sit-up tests. Those scoring 5 or 6 were categorized in the high strength group. Functional health status was assessed by responses to questions about the participant's ability to perform light, moderate, and strenuous recreational, household, daily living, and personal care tasks. RESULTS: After an average follow-up of 5 yr, 7% of men and 12% of women reported at least one functional limitation. A logistic regression model including age, aerobic fitness, body mass index, and new health problems at follow-up found that, relative to those with lower levels of strength, the odds of reporting functional limitations at follow-up in men and women categorized as having higher levels of strength were 0.56 (95%CI = 0.34, 0.93) and 0.54 (95%CI = 0.21, 1.39), respectively. CONCLUSIONS: These findings, if replicated in other populations, suggest that maintenance of strength throughout the lifespan may reduce the prevalence of functional limitations.

The value of strength training for older adults.

Health in older adults can best be measured in terms of functional status. Skeletal muscle strength has been reported to be a determinant of functional status in older individuals. Two major contributors to the decline in muscle function as a person ages are disuse and physical inactivity. Declining muscle function through a loss of muscular strength may decrease functional independence and mobility and increase the risk for falls and injuries, physical frailty, and disability. Older individuals lacking an appropriate amount of muscular strength may not be able to perform various activities of daily living, which are important indicators of independence.

Physical fitness, physical activity, and functional limitation in adults aged 40 and older.

PURPOSE: A cohort of middle-aged and older men and women were followed for an average of 5.5 yr to examine the association between physical fitness, physical activity, and the prevalence of functional limitation. METHODS: The participants received medical assessments between 1980 and 1988 and responded to a mail-back survey regarding functional status in 1990. RESULTS: Among 3495 men and 1175 women over 40 yr of age at baseline, 350 (7.5%) reported at least one functional limitation in daily or household activities at follow-up. The prevalence of functional limitation was higher among women than men. Physically fit and physically active participants reported less functional limitation than unfit or sedentary participants. After controlling for age and other risk factors, the prevalence of functional limitation was lower for both moderately fit (odds ratio = 0.4, 95% CI = 0.2-0.6) and high fit men (odds ratio = 0.3, 95% CI = 0.2-0.4), compared with low fit men. Corresponding figures for women were 0.5 (0.3-0.7) and 0.3 (0.2-0.5) for moderately fit and high fit women. The association between physical activity and functional limitation was similar to the data for physical fitness. CONCLUSIONS: These data support a protective effect of physical fitness and physical activity on functional limitation among older adults and extend this protective effect to middle-aged men and women.

Relations of sit-up and sit-and-reach tests to low back pain in adults.

The sit-up and sit-and-reach tests are found on nearly all youth and adult fitness tests because of the perceived relation between performance on these tests and low back pain. However, this relationship has not been well validated. Therefore, the purpose of the study was to examine the relationship between performance on these two common field tests of muscular strength and flexibility (the sit-up and the sit-and-reach tests) and self-reported low back pain (LBP). The sample included 2,747 adults with a mean age of 44.6 +/- 9.8 years. The 1-minute sit-up (mean = 30.9 +/- 10.6) and sit-and-reach tests (mean = 39.88 +/- 10.49 cm) were administered to participants as part of a voluntary clinical health and fitness evaluation between 1980 and 1990. Participants completed a mail-back survey in 1990 on musculoskeletal health problems. Low back pain was quantified by developing on ordinal variable from questionnaire responses which represented a range of severity of LBP from none (0) to LBP which required medical care (3). With an average of 6.1 (+/- 2.0) years of follow-up, LBP was reported by 54% of the study participants (men = 45%, women = 54%). Pearson correlations between sit-up (r = .002; p = .94), sit-and-reach (r = -.043; p = .03), and LBP indicated poor LBP criterion-related validity from the sit-up and sit-and-reach tests. Partial correlations, where age, gender, percent of body fat, and time between testing and survey response were controlled, displayed no increase in the relationship. This study does not support the validity of sit-up and sit-and-reach test items for health-related fitness batteries because they were unrelated to LBP.

Clinical feasibility of a free-weight strength-training program for older adults.

BACKGROUND: An emerging trend in the field of gerontology is the recognition that older adults, especially the frail elderly population, can increase their levels of strength and thus improve functional capability. Social acceptance of physical frailty and provision of care and assistance to dependent persons has now turned to helping the frail elderly adults maintain or improve functional independence. METHODS: The purpose of our study was to show the feasibility and effectiveness of a low-cost strength-training program using free weights for increasing strength and functional fitness among older adult volunteers. Participants aged 73 to 94 years were residents of a multilevel care retirement community in Columbia, SC. The strength-training program, led by an instructor, used dumbbells and ankle weights and was conducted in a multipurpose recreation room at the retirement facility. RESULTS: Functional performance measures (timed chair stand, 6-meter walk, stair climb, balance) handgrip strength, and self-assessment of activity level were outcome measures. All 25 participants completed the strength-training program. The average program adherence rate of all participants was 87 percent. No participant injuries or other adverse effects were observed. Functional performance measures improved significantly among program participants, with the greatest improvement in the timed chair stand (33.5 percent improvement) and the stair climb (17.6 percent improvement). CONCLUSION: Free-weight strength-training programs are appropriate for older adults, can be implemented in community settings, and are associated with significant improvement in functional performance.

Effect of body mass index on activity limitation and mortality among older women: the National Health Interview Survey, 1986-1990.

We assessed the impact of body mass on the association between activity limitations due to chronic conditions and mortality among 24,612 noninstitutionalized white or African American women aged > or = 65 years who participated in a National Health Interview Survey between 1986 and 1990. We found that more African American women had activity limitations than white women (59% vs 46%, respectively). The difference by race was greatest (19% vs 10%) for the most severe limitation (unable to perform the major activity). For women aged 65-69, the major activity was working or keeping house; for those aged > or = 70, it was the ability to live independently. For white women in all three categories of body mass index (BMI) and for African American women with BMI 15%-85%, the risk of dying was significantly higher for those unable to perform the major activity than for those with no limitations, controlling for the effects of education, marital status, and perceived health. The findings confirm the established link between low BMI and mortality and between activity limitations and mortality. Additionally, the findings further suggest that activity limitations linked to chronic conditions increase the risk of death within each stratum of BMI after adjusting for potential confounders.

The feasibility of conducting strength and flexibility programs for elderly nursing home residents with dementia.

A strength and flexibility training program was designed to determine the feasibility of conducting such a program with elderly nursing home residents with dementia. Training sessions included a warm-up and cool-down to improve flexibility, and a variety of strength exercises using Therabands to improve strength. Ten subjects met three times per week for 20 minutes each session. Throughout the program, the number of repetitions and the resistance of the Therabands was increased. At the end of the 11-week training program, improvements occurred in strength and flexibility. We conclude that this strength training program is feasible to conduct for elderly persons with dementia.

Anxiety, depression, physical fitness, and all-cause mortality in men.

The association of low physical fitness with an increased risk of mortality is independent of physiological risk factors, but psychological variables such as anxiety and depression have not been evaluated as possible confounders for all-cause mortality. The purpose of this study was to evaluate the possible confounding effects of anxiety and depression on the relation between physical fitness and mortality in male patients who were given a preventive medical examination between 1977-1986. Physical fitness was measured by maximal exercise treadmill testing. Anxiety and depression were measured by the Clinical Analysis Questionnaire. During follow-up, 83 men died. These cases, aged 19-76 yr, were combined for analyses with 323 randomly selected comparison subjects aged 19-80 yr. The crude odds ratio (95% confidence intervals) for dying in the unfit men was 2.0 (1.1,3.5) compared to the physically fit men. This finding was essentially unchanged after adjustment for anxiety (2.0 (1.1,3.5)), depression (2.1 (1.2,3.8)), or anxiety and depression (2.1 (1.1,3.5)). The increased risk of death in unfit men is not confounded by anxiety or depression. Thus, the higher all-cause death rate in unfit men cannot be explained by higher levels of anxiety or depression.

The relationship between sociodemographic characteristics and recruitment, retention, and health improvements in a worksite health promotion program.

BACKGROUND: Recruitment, retention, and success in a worksite health promotion program was examined among various demographic groups of employees (n = 11,830) of the Dallas, Texas Independent School District. METHODS: Enrolled employees (n = 3,873) were given a health screen consisting of health habit assessment, measurement of clinical variables, physical fitness testing, and a medical examination. RESULTS: Thirty-three percent of employees were successfully recruited into the program. Recruitment rates were virtually identical for men and women (32% and 33%, respectively), but varied across ethnic, age, and education groups. Blacks, younger employees, and noncollege graduates were less likely to be recruited. Sixty-nine percent of the employees were retained in the program, as defined by participation in the second screen, and women were more likely to be retained than men (71% versus 64%, respectively). Retention rates throughout the 10-week program were higher for whites and Hispanics, and were virtually identical for each age group and education level. Overall, participants in the program showed an improvement in physical fitness and general well-being, lost weight, and smoked less. These changes were relatively consistent across the various demographic groups. DISCUSSION: Data suggest demographic characteristics are related to recruitment and retention in a health promotion program.

The impact of previous athleticism on exercise habits, physical fitness, and coronary heart disease risk factors in middle-aged men.

A longitudinal study was performed to determine differences in physiologic variables, health behaviors, risk factors, or clinical status between former athletes (FA) (N = 345) and nonathletes (NA) (N = 75). The subjects, 420 self-referred white males aged 25-60 years old, were examined for prior athleticism and health. Athleticism was determined through self-reported high school or college athletic history. Baseline physiologic and health behavior characteristics were not different between the two groups. Of those study participants (N = 203 FA, 48 NA) who were sedentary at baseline, 208 (N = 167 FA, 41 NA) voluntarily began an exercise program during the followup period (average followup = 56 months). These numbers correspond to exercise adoption rates of 82 and 85% for FA and NA respectively, and were not statistically different (95% CI FA = 0.76, 0.88, NA = 0.73, 0.97). Repeated measures analysis of covariance was performed to determine if physiologic responses to adoption were different between FA and NA. No statistically significant difference was found between the two groups, time effects were similar in the two, and no significant interaction of time by group was observed. We conclude that prior athleticism has little apparent impact on health and health behaviors, thus suggesting that contemporaneous exercise has more impact on clinical variables.