Changes in physical fitness and changes in mortality

BACKGROUND: Point estimates of physical fitness give important information on the risk of death in healthy people, but there is little information available on effects of sequential changes in physical fitness on mortality. We studied this latter aspect in healthy middle-aged men over a total follow-up period of 22 years. METHODS: 2014 healthy men aged 40-60 years had a bicycle exercise test and clinical examination, and completed a questionnaire in 1972-75 (survey 1). This was repeated for 1756 (91%) of 1932 men still alive by Dec 31, 1982 (survey 2). The exercise scores were adjusted for age. The change in exercise scores between surveys was divided into quartiles (Q1=least fit, Q4=fittest). An adjusted Cox's proportional hazards model was used to study the association between changes in physical fitness and mortality, with the Q1 men used as controls. FINDINGS: By Dec 31, 1994, 238 (17%) of the 1428 men had died, 120 from cardiovascular causes. There were 37 deaths in the Q4 group (19 cardiovascular); their relative risks of death were 0.45 (95% CI 0.29-0.69) for any cause and 0.47 (0.26-0.86) for cardiovascular causes. There was a graded, inverse relation between changes in physical fitness and mortality irrespective of physical fitness status at survey 1. INTERPRETATION: Change in physical fitness in healthy middle-aged men is a strong predictor of mortality. Even small improvements in physical fitness are associated with a significantly lowered risk of death. If confirmed, these findings should be used to influence public health policy.     

Energy requirements and physical activity in free-living older women and men: a doubly labeled water study

Determinants of daily energy needs and physical activity are unknown in free-living elderly. This study examined determinants of daily total energy expenditure (TEE) and free-living physical activity in older women (n = 51; age = 67 +/- 6 yr) and men (n = 48; age = 70 +/- 7 yr) by using doubly labeled water and indirect calorimetry. Using multiple-regression analyses, we predicted TEE by using anthropometric, physiological, and physical activity indexes. Data were collected on resting metabolic rate (RMR), body composition, peak oxygen consumption (VO2 peak), leisure time activity, and plasma thyroid hormone. Data adjusted for body composition were not different between older women and men, respectively (in kcal/day): TEE, 2,306 +/- 647 vs. 2,456 +/- 666; RMR, 1,463 +/- 244 vs. 1,378 +/- 249; and physical activity energy expenditure, 612 +/- 570 vs. 832 +/- 581. In a subgroup of 70 women and men, RMR and VO2 peak explained approximately two-thirds of the variance in TEE (R2 = 0.62; standard error of the estimate = +/-348 kcal/day). Crossvalidation of this equation in the remaining 29 women and men was successful, with no difference between predicted and measured TEE (2,364 +/- 398 and 2,406 +/- 571 kcal/day, respectively). The strongest predictors of physical activity energy expenditure (P < 0.05) for women and men were VO2 peak (r = 0.43), fat-free mass (r = 0.39), and body mass (r = 0.34). In summary, RMR and VO2 peak are important independent predictors of energy requirements in the elderly. Furthermore, cardiovascular fitness and fat-free mass are moderate predictors of physical activity in free-living elderly.     

Physical activity for decreasing cardiovascular mortality and total mortality. A public health perspective

Forty years of epidemiological research have shown that physical activity as well as physical fitness are inversely related to cardiovascular and all-cause mortality in men and women. This association is likely to be causal. The moderate and most active or fit individuals experience mortality rates that are approximately one-third to one half lower than the rates among those least active or fit. Furthermore, moderate or high levels of physical activity or cardiorespiratory fitness seem to protect against the influence of other potential predictors on mortality. There appears to be a dose-response curve. The greatest benefit is registered when the least active become moderately active or fit. In western societies the prevalence of physical inactivity has been found to be as high as 40%. Exercise guidelines, as traditionally prescribed for disease prevention and improvement of aerobic capacity, unfortunately have failed to enhance the level of physical activity. Currently, exercise training is being extended to include broader physical activity. This new paradigm emphasizes the potential effectiveness of moderately intense activities of daily life (lifestyle activity) for achieving health benefit, and aims at improving levels of general energy expenditure throughout the day. This paper analyses the actual epidemiological evidence for these new recommendations and discusses approaches at different levels of physical activity intervention including individual, community, organisational, environmental and policy-level strategies to increase the activity levels of inactive population groups as well as across the population as a whole.     

Associations between skeletal muscle properties, physical fitness, physical activity and coronary heart disease risk factors in men

High physical fitness and physical activity are associated with favourable lipid levels, especially a high level of high density lipoprotein cholesterol (HDL-C). A person's skeletal muscle properties, metabolism and percentage of different muscle fibres (ST-%), which may modify coronary heart disease (CHD) risk factors, such as serum insulin, obesity and serum sex hormones may also influence his fitness level and leisure-time physical activity. We studied the associations of physical fitness, physical activity and ST-% with serum lipids and lipoproteins in 72 healthy men. Their parameters were compared with those of 20 men with defined CHD. Significant interrelationships between ST-%, fitness and leisure-time physical activity index (LTPAI) were observed. Multiple regression analysis showed that ST-%, fitness and leisure-time physical activity explained about 32% of the variation in HDL-C in the healthy men. In healthy men ST-% correlated positively with fitness (r(s) = 0.62, P < 0.001) and with LTPAI (r(s) = 0.62, P < 0.001). Fitness level also correlated significantly with LTPAI (r(s) = 0.81, P < 0.001). Serum insulin showed negative associations with ST-% (r(s) = -0.63, P < 0.001) and fitness (r(s) = -0.54, P < 0.001) and LTPAI (r(s) = -0.62, P < 0.001). Free fraction of testosterone correlated negatively with serum HDL-C level (r(s) = -0.34, P < 0.01), with fitness (r(s) = -0.41, P < 0.001) and with LTPAI (r(s) = -0.54, P < 0.001). In sedentary men with the lowest fitness and physical activity the mean of ST-% (45%) was similar to that in CHD patients (44%). However, ST-% in men in the highest tertile of physical activity and fitness (68%) was significantly higher than in CHD patients and in men in the lowest tertile of physical activity and fitness. Skeletal muscle enzyme activity in lipid metabolism was significantly lower in both CHD patients and in sedentary and low-fit men than that in fitter and physically active men. The present data imply that skeletal muscle properties are important determinants of risk profiles, such as physical activity, fitness and serum lipid and lipoprotein patterns. Although fitness is a graded, independent predictor of mortality from CHD, a relatively high fitness level is not enough. This was clearly observed in the clustering analysis, in which the healthy men, according to their ST-%, fitness, leisure-time physical activity and serum sex hormone binding globulin (SHBG), fell into three natural groups: (i) Inactive men with lowest ST-% (mean 42%), lowest fitness (10.7 METs) and lowest HDL-C (1.36 mm/l); (ii) Fit men with high ST-% (66%), high fitness (14.5 METs) and moderately high HDL-C (1.54 mol/l); (iii) Active men with high ST-% (66%), highest fitness (14.9 METs) and highest serum HDL (1.83 mmol/l). The results support the idea that both fitness and physical activity give further protection against CHD by modifying risk factors. Our findings also suggest that skeletal muscle properties should be considered in the studies which assess CHD risk factors and their modifications especially in the field of health-related fitness.     

Effects of 60 Hz electromagnetic fields on early growth in three plant species and a replication of previous results

OBJECTIVE: To examine the relation between obstetric factors and the prevalence of urinary incontinence three months after delivery. DESIGN: 2134 postal questionnaires sent between August 1989 and June 1991. SETTING: Teaching hospital in Dunedin, New Zealand. SUBJECTS: All women three months postpartum who were resident in the Dunedin area. MAIN OUTCOME MEASURE: Prevalence of urinary incontinence. RESULTS: 1505 questionnaires were returned (70.5% response rate). At three months postpartum 34.3% of women admitted to some degree of urinary incontinence with 3.3% having daily or more frequent leakage. There was a significant reduction in the prevalence of incontinence for women having a caesarean section, in particular in primiparous women with a history of no previous incontinence (prevalence of incontinence following a vaginal delivery 24.5%, following a caesarean section 5.2% P = 0.002). There was little difference between elective caesarean sections and those carried out in the first and second stages of labour. The odds ratios for women having a caesarean section were 0.4 (95% confidence interval (CI) 0.2.-0.7) (all women and all primiparae) and 0.2 (95% CI 0.0-0.6) (primipara with no previous incontinence) in comparison with those having a normal vaginal delivery. The prevalence of incontinence was also significantly lower in women having had two caesarean sections (23.3%; P = 0.05) but similar in those women having three or more caesarean sections (38.9%) in comparison with those women who delivered vaginally (37.7%). Other significant independent odds rations were found for daily antenatal pelvic floor exercises (PFE) (0.6, 95% CI 0.4-0.9), parity > or = 5 (2.2, 95% CI 1.0-4.9) and pre-pregnancy body mass index (1.07, 95% CI 1.04-1.10). CONCLUSIONS: Adverse risk factors for urinary incontinence at three months postpartum are vaginal delivery, obesity and multiparity (> or = 5). Caesarean section and daily antenatal PFE appear to be protective, although not completely so.     

Smaller lungs in women affect exercise hyperpnea

We subjected 29 healthy young women (age: 27 +/- 1 yr) with a wide range of fitness levels [maximal oxygen uptake (VO2 max): 57 +/- 6 ml . kg-1 . min-1; 35-70 ml . kg-1 . min-1] to a progressive treadmill running test. Our subjects had significantly smaller lung volumes and lower maximal expiratory flow rates, irrespective of fitness level, compared with predicted values for age- and height-matched men. The higher maximal workload in highly fit (VO2 max > 57 ml . kg-1 . min-1, n = 14) vs. less-fit (VO2 max < 56 ml . kg-1 . min-1, n = 15) women caused a higher maximal ventilation (VE) with increased tidal volume (VT) and breathing frequency (fb) at comparable maximal VT/vital capacity (VC). More expiratory flow limitation (EFL; 22 +/- 4% of VT) was also observed during heavy exercise in highly fit vs. less-fit women, causing higher end-expiratory and end-inspiratory lung volumes and greater usage of their maximum available ventilatory reserves. HeO2 (79% He-21% O2) vs. room air exercise trials were compared (with screens added to equalize external apparatus resistance). HeO2 increased maximal expiratory flow rates (20-38%) throughout the range of VC, which significantly reduced EFL during heavy exercise. When EFL was reduced with HeO2, VT, fb, and VE (+16 +/- 2 l/min) were significantly increased during maximal exercise. However, in the absence of EFL (during room air exercise), HeO2 had no effect on VE. We conclude that smaller lung volumes and maximal flow rates for women in general, and especially highly fit women, caused increased prevalence of EFL during heavy exercise, a relative hyperinflation, an increased reliance on fb, and a greater encroachment on the ventilatory "reserve." Consequently, VT and VE are mechanically constrained during maximal exercise in many fit women because the demand for high expiratory flow rates encroaches on the airways' maximum flow-volume envelope.     

Physical activity, physical fitness, and all-cause and cancer mortality: a prospective study of men and women

We studied physical fitness and physical activity in relation to all-cause and cancer mortality in a cohort of 7080 women and 25,341 men examined at the Cooper Clinic in Dallas, Texas, during 1970 to 1989. Physical fitness was assessed at baseline by a maximal treadmill exercise test, while physical activity was self-reported on the attendant health habits questionnaire. Both men and women averaged about 43 years of age at baseline (range, 20 to 88 years), and they were followed for approximately 8 years on average. Through the end of 1989, the women contributed 52,982 person-years of observation and incurred 89 deaths, including 44 deaths due to cancer. The men contributed 211,996 person-years and incurred 601 deaths, with 179 due to cancer. After adjustment for baseline differences in age, examination year, cigarette habit, chronic illnesses, and electrocardiogram abnormalities, we found a strong inverse association between risk of all-cause mortality and level of physical fitness in both men and women (P for trend < 0.001). Physically active men also were at lower risk of all-cause mortality than were sedentary ones (P for trend = 0.01). Among women, however, self-reported physical activity was not significantly related to risk of death from all causes. The risk of mortality from cancer declined sharply across increasing levels of fitness among men (P for trend < 0.001), whereas among women the gradient was suggestive but not significant (P for trend = 0.07). Physically active men also were at lower risk of death from cancer than were sedentary men (P for trend = 0.002), but among women physical activity was unrelated to cancer mortality.     

The Troms? Study: physical activity and the incidence of fractures in a middle-aged population

We have studied the relation of occupational and recreational physical activity to fractures at different locations. All men born between 1925 and 1959 and all women born between 1930 and 1959 in the city of Troms? were invited to participate in surveys in 1979-1980 and 1986-1987 (The Troms? Study). Of 16,676 invited persons, 12,270 (73.6%) attended both surveys. All nonvertebral fractures (n = 1435) sustained from 1988 to 1995 were registered in the only hospital in the area. Average age in the middle of the follow-up period (December 31, 1991) was 47.3 years among men and 4501 years among women, ranging from 32 to 66 years. Fracture incidence increased with age at all locations among women, but it decreased with or was independent of age among men. Low-energetic fractures constituted 74.4% of all fractures among women and 55.2% among men. When stratifying by fracture location, the most physically active persons among those 45 years or older suffered fewer fractures in the weight-bearing skeleton (relative risk [RR] 0.6, confidence interval [CI] 0.4-0.9, age-adjusted), but not in the non-weight-bearing skeleton (RR 1.0, CI 0.7-1.2, age-adjusted) compared with sedentary persons. The relative-risk of a low-energetic fracture in the weight-bearing skeleton among the most physically active middle-aged was 0.3 (CI 0.1-0.7) among men and 0.9 (CI 0.4-1.8) among women compared with the sedentary when adjusted for age, body mass index, body height, tobacco smoking, and alcohol and milk consumption. It seems that the beneficial effect on the skeleton of weight-bearing activity is reflected also in the incidence of fractures at different sites.     

The moderating influence of physical fitness on age gradients in vigilance and serial choice responding tasks.

The moderating influence of physical fitness on age gradients in measures obtained from vigilance and serial choice responding tasks is examined in a sample of 90 postal workers. Physiological data relating to aerobic fitness determined fitness level within 2 age groups: younger participants ages 18 to 30 years (M ?=?25.19; 24 men, 24 women) and older participants ages 43 to 62 years (M ?=?49.19; 20 men, 22 women). A performance decrement across time was found in several measures, and some variation as a function of age was apparent. However, post hoc statistical analyses did not indicate this was due to older adults underperforming younger adults. According to predictions, significant Age?×?Fitness interactions showed older less fit workers to consistently underperform other participants. The findings suggest that older less fit individuals have lower signal sensitivity and processing speed than older fitter people and younger individuals. Results are discussed in relation to underlying physiological mechanisms. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Habitual physical activity in a population residing in the city of Barcelona

OBJECTIVES: To describe the sociodemographic distribution of habitual physical activity and to analyse its relationship with self-perceived health status and occupational status, among the population older that 16 years of age in the city of Barcelona, Spain. METHODS: A sample of 1,885 adult men and 2,196 women answered the Health Interview Survey of Barcelona in 1992. Those whose habitual activity required high physical exertion or walking were considered as active. Bivariate and multivariate analyses adjusting logistic regression models were used to study the relationship between habitual physical activity and the rest of variables, for each occupational situation. RESULTS: Fifty six percent of adults reported being physically active. Physical activity was lower among workers than non workers, although workers reported more physical exertion (14.5% in men and 8.0% in women). Physical activity was associated with occupation and educational level among male workers, but only with occupation among female workers. In the non working population, physical activity was lower among those who perceived their health status as fair or poor, compared with those that described it as good or very good, (ORa in men was 0.2, 95% confidence interval = 0.1-0.5; ORa in women was 0.5, 95% confidence interval = 0.3-0.8). CONCLUSIONS: More than half of the Barcelona population were physically active in an habitual manner. Among workers, this activity was mainly determined by the occupation. Non-workers with a poor self-perceived health status did less physical activity.     

Changes in physical activity, mortality, and incidence of coronary heart disease in older men

BACKGROUND: We studied the relations between physical activity and changes in physical activity, all-cause mortality, and incidence of major coronary-heart-disease events in older men. METHODS: In 1978-80 (Q1), 7735 men aged 40-59 were selected from general practices in 24 British towns, and enrolled in a prospective study of cardiovascular disease, which included physical activity data. In 1992 (Q92), 12-14 years later, 5934 of the men (91% of available survivors, mean age 63 years) gave further information on physical activity and were then followed up for a further 4 years. The main endpoints were all-cause mortality during 4 years of follow-up from Q92, and major fatal and non-fatal coronary-heart-disease events during 3 years of follow-up from Q92. FINDINGS: Among 4311 men with no history of coronary heart disease, stroke, or "other heart trouble" by Q92 and who did not report "poor health", there were 219 deaths. In the inactive/occasionally active, light, moderate, and moderately vigorous/vigorous activity groups there were 101 (18.5/1000 person-years) 48 (11.4), 23 (7.3), and 47 (9.1) deaths, respectively (adjusted risk ratios 1.00, 0.61 [95% CI 0.48-0.86], 0.50 [0.31-0.79], 0.65 [0.45-0.94]). Men who were sedentary at Q1 and who began at least light activity by Q92 had significantly lower all-cause mortality than those who remained sedentary, even after adjustment for potential confounders (risk ratio=0.55 [0.36-0.84]). Physical activity improved both cardiovascular mortality (0.66 [0.35-1.23]) and non-cardiovascular mortality (0.48 [0.27-0.85]). The relation between physical activity at Q92, changes in physical activity, and mortality were similar for men with pre-existing cardiovascular disease. INTERPRETATION: Maintaining or taking up light or moderate physical activity reduces mortality and heart attacks in older men with and without diagnosed cardiovascular disease. Our results support public-health recommendations for older sedentary people to increase physical activity, and for active middle-aged people to continue their activity into old age.     

Glycine receptor reduction within segmental gray matter in a rat model in neuropathic pain

OBJECTIVES: To determine the prevalence rates of self-reported sleep complaints and their association with health-related factors. DESIGN: A cross-sectional study. SETTING: People living in the community. PARTICIPANTS: A total of 2398 noninstitutionalized individuals, aged 65 years and older, residing in the Veneto region, northeast Italy. MEASUREMENTS: Odds ratios for the association of sleep complaints with potential risk factors. RESULTS: The prevalence of insomnia was 36% in men and 54% in women, with increased risks for women (odds ratio (OR) = 1.69, 95% CI: 1.3-2.1), depression (OR = 1.93, 95% CI, 1.5-2.5), and regular users of sleep medications (OR = 5.58, 95% CI, 4.3-7.3). About 26% of men and 21% of women reported no sleep complaints. Night awakening, reported by about two-thirds of the participants, was the most common sleep disturbance. Women and regular users of sleep medications had significantly increased odds for insomnia and for not feeling rested upon awakening in the morning. Depressive symptomatology was more strongly associated with insomnia and night awakening than with awakening not rested, whereas physical disability was more strongly associated with awakening not rested than with the other two sleep disturbances. CONCLUSION: Our findings show that sleep complaints, highly common among older Italians, are associated with a wide range of medical conditions and with the use of sleep medications. Further longitudinal studies are needed to investigate the causes and the negative health consequences of sleep disturbances to improve both the diagnosis and treatment.     

High body fatness, but not low fat-free mass, predicts disability in older men and women: the Cardiovascular Health Study

Using data from the Cardiovascular Health Study, we studied the relation between body composition (fat mass and fat-free mass, assessed by bioelectrical impedance) and self-reported, mobility-related disability (difficulty walking or stair climbing) in 2714 women and 2095 men aged 65-100 y. In a cross-sectional analysis at baseline (1989-1990), disability was reported by 26.5% of the women and 16.9% of the men. A positive association was observed between fat mass and disability. The odds ratio for disability in the highest quintile of fat mass was 3.04 (95% CI: 2.18, 4.25) for women and 2.77 (95% CI: 1.82, 4.23) for men compared with those in the lowest quintile. Low fat-free mass was not associated with a higher prevalence of disability. In a longitudinal analysis among persons not reporting disability at baseline, 20.3% of the women and 14.8% of the men reported disability 3 y later. Fat mass at baseline was predictive of disability 3 y later, with odds ratios of 2.83 (95% CI: 1.80, 4.46) for women and 1.72 (95% CI: 1.03, 2.85) for men in the highest quintile of fat. The increased risk was not explained by age, physical activity, chronic disease, or other potential confounders. Low fat-free mass was not predictive of disability. The results showed that high body fatness is an independent predictor of mobility-related disability in older men and women. These findings suggest that high body fatness in old age should be avoided to decrease the risk of disability.     

Lifelong exercise and stroke

OBJECTIVES: To examine the potential of lifelong patterns of increased physical activity to prevent stroke. DESIGN: Case-control study. SETTING: 11 general practices in west Birmingham. SUBJECTS: 125 men and women who had just had their first stroke and were aged 35-74 and 198 controls frequency matched for age and sex recruited over 24 months during 1988-90. Exclusion criteria were a previous history of stroke, mitral valvular heart disease combined with atrial fibrillation, primary or metastatic cerebral neoplasm, or coagulation disorder or myeloproliferative disease. MAIN OUTCOME MEASURES: Odds ratios for stroke related to lifetime history of exercise after 15 years of age. RESULTS: A history of vigorous exercise during the ages 15-25 appeared to protect from stroke: odds ratio adjusted for age and sex 0.33 (95% confidence interval 0.2 to 0.6). This effect was independent of other potential risk factors. Increasing years of participation in vigorous exercise between the ages of 15 and 55 produced an increasing protection from stroke (p < 0.001). In the 65 cases and 169 controls who were free of cardiac ischaemia, peripheral vascular disease, and poor health recent vigorous exercise and walking were protective against stroke: odds ratios of 0.41 (0.2 to 1.0) for recent vigorous exercise and 0.30 (0.1 to 0.7) for recent walking. CONCLUSIONS: Appreciable protection from stroke in later life is conferred by vigorous exercise in early adulthood. This increased level of physical activity should, if possible, be continued lifelong.     

Self-reported rectal bleeding in a United States community: prevalence, risk factors, and health care seeking

OBJECTIVE: Little data on rectal bleeding in the U.S. population are available. We therefore sought to assess the prevalence of different types of rectal bleeding, their association with potential risk factors including other colonic symptoms, and predictors of health care seeking in a U.S. community. METHODS: We used a crossectional survey by mail, applying a previously validated self-report symptom questionnaire. Our population comprised an age- and gender-stratified random sample of Olmsted County, Minnesota residents aged 20-64 yr. RESULTS: In total, 1643 responded (77%). Rectal bleeding was reported by 235 subjects (age- and gender-adjusted prevalence, 15.5 per 100; 95% confidence interval [CI], 13.6-17.4); 218 found blood on wiping, 74 noted blood coating the stools, and 46 reported dark blood mixed in the stools. The prevalence of rectal bleeding was significantly higher in younger persons (18.9%, 20-40 yr vs 11.3% > 40 yr; p < 0.001). By stepwise logistic regression analysis, constipation (odds ratio [OR] = 3.03; 95% CI, 2.09-4.41) and diarrhea (OR = 1.90; 95% CI, 1.25-2.84) were independent predictors of rectal bleeding. Among those with rectal bleeding, 13.9% (95% CI, 9.6-19.1%) had visited a physician for bowel problems in the prior yr; only a history of abdominal surgery was an independent predictor of physician visits but this explained just 15.9% of the deviance. CONCLUSIONS: In otherwise healthy young and middle-aged persons, approximately one in seven have a history of rectal bleeding and this is more frequent in younger people; only a minority seek health care and this is not related to symptom status.     

Six-month physical activity and fitness changes in Project Active, a randomized trial

PURPOSE: Project Active is a randomized clinical trial (N = 235) comparing a lifestyle physical activity program with a structured exercise program in changing physical activity (total energy expenditure [kcal.kg-1.d-1]) and cardiorespiratory fitness (VO2peak in mL.kg-1.min-1). METHODS: Sedentary but healthy adults (N = 235) aged 35-60 years received 6 months of intensive intervention. RESULTS: Analysis of covariance (ANCOVA), adjusting for baseline measure, age, gender, body mass index (BMI), cohort, and ethnicity, showed that at 6 months both lifestyle and structured groups significantly increased energy expenditure over baseline (P < 0.001). The mean increases +/- SE, 1.53 +/- 0.19 kcal.kg-1.d-1 for the lifestyle group and 1.34 +/- 0.20 kcal.kg-1 d-1 for the structured group, were not significantly different between groups (P = 0.49). For cardiorespiratory fitness, both groups had significant increases from baseline (P < 0.001). Mean increases +/- SE were 1.58 +/- 0.33 mL.kg-1.min-1 and 3.64 +/- 0.33 mL.kg-1.min-1 for the lifestyle and structured groups, respectively. This was significantly greater in the structured group (P < 0.001). We also studied changes in intensity of physical activity. Both groups significantly increased moderate intensity activity from baseline, but the increase was significantly greater in the lifestyle group than the structured group (P = 0.02). In contrast, the structured group increased its hard activity more than the lifestyle group, but the difference was not significantly different (P = 0.02). In contrast, the structured group increased its hard increased (P < 0.01) for both groups by 0.25 kcal.kg-1.d-1. CONCLUSION: Both intervention approaches are effective for increasing physical activity and fitness over a 6-month period in initially sedentary men and women.     

Physical inactivity in New Zealanders aged 60 years and older

AIMS: To determine the prevalence of physical inactivity among older New Zealanders (> or = 60 years) and to examine the patterns of physical inactivity by sex, age, residential and cognitive status. METHODS: Information on housework-related and leisure-time physical activities obtained from the 910 controls in the Auckland Hip Fracture Study, was used to determine the prevalence of inactivity. Direct standardisation was used to extrapolate the inactivity prevalence figures from the study population to the general Auckland population. Logistic regression analyses were undertaken to examine the patterns of physical inactivity by sex, age, residential and cognitive status. RESULTS: Of the study participants 48.7% did not undertake any leisure-time physical activities and 15.6% did not undertake any physical activity. Extrapolation of these data to the Auckland population indicated that 38.9% of older people do not participate in any leisure time activity and 6.1% do not partake in any physical activity. Non-participation in physical activities was shown to be greater for women (odds ratio = 1.92; 95% confidence interval: 0.98-4.07); those in the older age groups (> or = 90 years, 7.00; 1.88-45.60); those living in institutions (6.52; 4.01-10.64); and for those who were cognitively impaired (13.96; 7.06-28.92). CONCLUSION: Policies and programmes should focus on encouraging and supporting older people to become physically more active, by engaging in activities in which they enjoy participating; by educating older people as to the feasibility and benefits of physical activities, including maintenance of an independent active life; and by encouraging residents in institutions to continue their involvement in housework-related activities, such as gardening, home maintenance and general housework.     

Enhanced coronary vasoconstriction in the Syrian myopathic hamster supports the microvascular spasm hypothesis

This study examines the relation between blood pressure and insulin resistance in obese, sedentary middle-aged and older men. Eleven hypertensive and 17 normotensive subjects of comparable age (58.6 +/- 1.0 years, mean +/- SEM), percent body fat (27.7 +/- 0.7%), and maximal aerobic capacity (30.2 +/- 0.9 mL.kg-1.min-1) participated in this study. Glucose disposal (M, milligrams per kilogram of fat-free mass per minute) determined during a three-dose hyperinsulinemic euglycemic clamp was lower in the hypertensive than normotensive subjects at the low (M at 120 pmol/m2.min: 2.3 +/- 0.2 versus 3.2 +/- 0.3, P = .06), intermediate (M at 600 pmol/m2.min: 8.0 +/- 0.6 versus 10.4 +/- 0.6, P = .02), and high (M at 3000 pmol/m2.min: 13.5 +/- 0.5 versus 15.5 +/- 0.7, P = .04) insulin infusion rates. The calculated insulin concentration necessary for a half-maximal effect (EC50) was greater in the hypertensive than normotensive subjects (1164 +/- 168 versus 864 +/- 66 pmol/L, P = .03). In this population of normotensive and hypertensive men, systolic, diastolic, and mean arterial blood pressures were related to glucose disposal at these insulin infusion rates (r = -.35 to -.46, P < .05) as well as the EC50 (r = .42 to .44, P < .05). Thus, hypertensive obese, sedentary older men have a reduction in both sensitivity and maximal responsiveness to insulin that is directly related to the severity of hypertension independent of obesity and physical fitness.     

Plasma fibrinogen levels in healthy postmenopausal women: physical activity and hormone replacement status

BACKGROUND: Fibrinogen is a major component of the coagulation system and a powerful independent risk factor for cardiovascular disease in postmenopausal women. Regular physical activity has been recommended as an effective clinical approach to lowering plasma fibrinogen levels; currently, however, there are little or no data to support a relationship between habitual exercise status and plasma fibrinogen levels in healthy postmenopausal women who either use or do not use hormone replacement therapy (HRT). METHODS: Plasma fibrinogen levels were measured in 20 physically active (56 +/- 1 yr) and 31 sedentary (58 +/- 1 yr) healthy postmenopausal women. Nine (45%) physically active and 15 (48%) sedentary women had been using HRT for > 1 year; the others were nonusers of HRT. RESULTS: Plasma fibrinogen levels were approximately 15% lower (p = .001) in the physically active women (2.48 +/- .08 g/L) than the sedentary controls (2.92 +/- .06 g/L) and approximately 7% lower (p = .04) in the users (2.65 +/- .08 g/L) versus nonusers (2.84 +/- .08 g/L) of HRT. Moreover, the lower (0.4 g/L) plasma fibrinogen levels associated with regular physical activity were evident in both the users (2.39 +/- .11 vs 2.80 +/- .08 g/L, p = .001) and nonusers (2.56 +/- .11 vs 3.03 +/- .08 g/L, p = .006) of HRT. Stepwise multiple regression analysis revealed that percent body fat was the primary determinant of plasma fibrinogen levels, accounting for 30% of the variability. CONCLUSIONS: Regular physical activity is associated with lower plasma fibrinogen levels in postmenopausal women; the lower plasma fibrinogen levels associated with regular physical activity are evident in both users and nonusers of HRT; and plasma fibrinogen levels are positively related to percent body fat in postmenopausal women differing in physical activity and HRT status. Lower plasma fibrinogen levels in physically active postmenopausal women may contribute to their lower risk of cardiovascular disease.     

Relationship between changes in physical activity and plasma insulin during a 2.5-year follow-up study

The association between changes in physical activity, body weight, and diet and fasting plasma insulin was analyzed in a 2.5-year follow-up study of 146 men aged 50 to 60 years. Physical activity was assessed by a 7-day physical activity recall interview, diet by a 4-day food record, and plasma insulin radioimmunologically. Total physical activity decreased from (mean +/- SD) 45.1 +/- 10.1 to 39.0 +/- 6.1 metabolic equivalent (MET) hours (METh).d-1 and conditioning physical activity (> 5.0 METs) from 8.0 +/- 11.2 to 2.7 +/- 5.0 METh.d-1, whereas plasma insulin increased from 8.2 +/- 5.8 to 9.2 +/- 6.7 mU.L-1 and body weight from 80.5 +/- 12.0 to 81.6 +/- 11.6 kg during the follow-up period (P < or = .001 for all). The change in conditioning physical activity correlated inversely (r = -.34, P < .001) and change in body weight positively (r = .42,P < .001) with the change in plasma insulin level. With data adjusted for the baseline insulin level, cardiovascular health status, alcohol intake, change in body weight, smoking, age, and follow-up time, the odds ratio for an increase in fasting plasma insulin was 8.9 (95% CI, 2.1 to 37.1; P = .003) for men with the greatest decrease in conditioning physical activity (< -7 METh) compared with men who reported an increase in conditioning physical activity. The same logistic regression model showed an odds ratio of 9.9 (95% CI, 2.1 to 45.4; P = .003) for the increase in plasma insulin for subjects who gained more than 3.3 kg body weight compared with subjects who lost at least 0.6 kg. Men who consumed at least 12 g.d-1 alcohol at both examinations had an odds ratio of 12.8 (95% CI, 1.7 to 94.5; P = .012) compared with nondrinkers. These data suggest that in middle-aged men, a reduction in physical activity increases the risk for increased plasma insulin independently of alcohol intake and changes in body weight.