Objectively and subjectively measured physical activity and its relation to cardiovascular risk factors in older people-Which is most appropriate?

OBJECTIVES: To determine the strength of the association between objectively and subjectively measured physical activity (PA) and cardiovascular risk factors (CVRF) in a sample of older adults to assess which measure of PA is most appropriate for use in this population. STUDY DESIGN AND OUTCOME MEASURES: The study was a cross-sectional analysis of a community-dwelling sample aged 60 years or more (61 women and 34 men). Data collection included anthropometric measurements, blood analytics, and objective and subjective measurements of PA from accelerometers and Yale PA Survey questionnaires, respectively. RESULTS: Although the questionnaire indicated a higher summary index (total units) of PA in men than in women, objective measurements of total PA (mean counts per minute and steps per day) did not differ by sex. However, we obtained different results between women and men when we analyzed the relation between objective and subjective PA parameters and CVRF. In women, parameters that indicate cardiovascular risk, such as body mass index (BMI), waist circumference (WC), glucose, and total cholesterol, negatively correlated with objective PA parameters, while HDLc positively correlated with objective PA parameters and negatively with subjective PA parameters. In men, BMI and WC were negatively correlated with objective PA parameters, while blood cholesterol, LDLc, and triglycerides negatively correlated with subjective PA parameters. CONCLUSIONS: In women, it seems more appropriate to use objective methods to measure PA, while in men, objective and subjective methods seem to be complementary. Both methods of measurement, accelerometers and questionnaires, should be used simultaneously in research studies in older populations to establish precise relationships between PA and cardiovascular risk.

Obesity parameters, physical activity, and physical fitness are correlated with serum dipeptidyl peptidase IV activity in a healthy population.

OBJECTIVE: To determine whether obesity, physical fitness, and physical activity parameters are associated with the enzymatic activity of serum dipeptidyl peptidase IV (sDPPIV) in a sample of healthy women and men. DESIGN AND METHODS: We have correlated parameters of obesity, physical fitness, and physical activity with sDPPIV activity in 374 healthy subjects (age: 60.7 ± 6.9 years, body mass index: 26.1 ± 4.1 kg/m2). Enzymatic activity was analyzed using spectrofluorimetry, body composition was assessed by impedanciometry, physical fitness data were obtained using the Senior Fitness Test, and physical activity data were collected by accelerometer. Pearson's partial correlation analysis was applied to determine the relationship between DPPIV activity and the rest of parameters and significantly correlated variables were introduced into linear regression models to predict DPPIV. RESULTS: Serum DPPIV activity was negatively associated with obesity parameters such as body mass (r = -0.112), body mass index (BMI) (r = -0.147), waist circumference (r = -0.164), waist-to-hip ratio (-0.104), and percentage of fat mass (r = -0.185). Serum DPPIV activity was positively associated with cardiovascular fitness (r = 0.138), total amount of physical activity (r = 0.153), and time spent doing light exercise (r = 0.184). Regression models revealed sex differences in enzyme activity with overall activity higher in women than in men (ß = 0.437, p < 0.001). Further, percent fat mass was an independent negative predictor of DPPIV activity (ß = -0.184, p = 0.001). Serum DPPIV activity was positively predicted based on the amount of time spent doing light physical activity (ß = 0.167, p = 0.001). CONCLUSION: Our results demonstrate that sDPPIV activity is positively associated with healthier parameters regarding fatness, fitness and physical activity.

Physical activity and dietary habits related to cardiovascular risk in independent community-living older women.

A side effect of increased life expectancy is a surge in sequelae of diseases and injuries, which in turn increase the duration of life with disability among the elderly. The aim of this study was to ascertain the physical activity and nutritional parameters that better predict cardiovascular risk in a cohort of older women. A cross-sectional study was designed including 65 women able to independently perform basic activities of daily life. Data collection included anthropometric measurement, blood pressure measurement, blood analytics, objectively measurement of physical activity, and dietary assessment. We were able to generate models that explain the relationship between physical activity, diet, and these health measurement parameters. We observed that the combination of moderate physical activity and a diet including protein-rich foods as nuts, dairy, and eggs were better predictors associated with favorable changes in risk factors for cardiovascular disease than age.

Sex differences in the aging pattern of renin-angiotensin system serum peptidases.

BACKGROUND: Serum peptidases, such as angiotensin-converting enzyme (ACE), angiotensin-converting enzyme-2 (ACE2), neutral endopeptidase (NEP), aminopeptidase N (APN), and aminopeptidase A (APA), are important elements of the renin-angiotensin system (RAS). Dysregulation of these enzymes has been associated with hypertension and cardiovascular risk. In the present study, serum activities of RAS peptidases were analyzed to evaluate the existence of sexual differences, with a possible different pattern in pre- and post-andropausal/post-menopausal participants. METHODS: One hundred and eighteen healthy men and women between 41 and 70 years of age (58 women and 60 men) were recruited to participate in the study. Serum RAS-regulating enzymes were measured by spectrofluorimetry. Enzymatic activity was recorded as units of enzyme per milliliter of serum (U/mL). RESULTS: Significantly lower serum APA activity was observed in men with respect to women; no sex differences were detected for ACE, ACE2, NEP, or APN. Significantly lower APA and ACE serum activity were observed in older men compared to older women. In contrast, younger (<55 years) men had significantly higher values of NEP serum activity than younger women. Significantly lower ACE serum activity was detected in older men compared to younger men. In women, significantly higher ACE2 serum activity was observed in older women compared to younger women. CONCLUSIONS: These results suggest a differential effect of aging on the activity of RAS enzymes in men and women, especially with respect to the breakpoint of andropausia/menopausia, on the critical serum enzymatic activities of the RAS, which could correlate with sexual differences in cardiovascular risk.

Relationship between physical activity and markers of oxidative stress in independent community-living elderly individuals.

The aim of the present study was to examine the relationship between objective data of physical activity and markers of oxidative stress in older men and women. Participants were old adults, aged≥60years (61 women and 34 men) who were all capable of performing basic daily activities by themselves and lived on their own. To describe physical activity we used objective data measured by accelerometers which record active and sedentary periods during everyday life for five days. Determination of oxidative stress was conducted from three perspectives: determination plasma total antioxidant status (TAS), plasma antioxidant enzyme activities, i.e., glutathione peroxidase (GPx), catalase (CAT) and superoxide dismutase (SOD), and membrane lipid peroxidation (TBARS). In the group of women, those who met physical activity recommendations (WR) had lower level of TAS. In addition, the moderate to vigorous physical activity (MVPA) was negatively correlated with TAS. Simultaneously, MVPA was correlated with increase in the GPx antioxidant enzyme activity, and the counts per minute were positively correlated with CAT activity. In the group of men, the cpm and the MVPA were negatively correlated with lipid peroxidation while lifestyle physical activity was positively correlated with CAT activity. These findings suggest that MVPA in the elderly although it is related to a decrease in the TAS in women, induces adaptive increase in antioxidant enzyme activity and decreases lipid peroxidation in both women and men. These results suggest that at this time of life, it is not only the amount of physical activity performed that is important but also its intensity.