Cardiorespiratory Fitness and the Risk of All-Cause, Cardiovascular and Cancer Mortality in Men with Hypercholesterolemia.

Background: Whether higher cardiorespiratory fitness (CRF) confers protection against cardiovascular disease (CVD) in individuals with manifest hypercholesterolemia is poorly understood. Methods: Participants were 8920 men aged 20−82 years with hypercholesterolemia but no history of CVD and/or cancer and who received a preventive examination at the Cooper Clinic in Dallas, TX, USA, during 1974−2001. CRF was quantified as maximal treadmill test duration and was grouped for analysis as low, moderate, or high based on the traditional Aerobics Center Longitudinal Study cutpoints. Using Cox regression analyses, we computed hazard ratios and 95% confidence intervals for risk of mortality based on CRF. Results: During an average of 17 years of follow-up, 329 CVD and 290 cancer deaths occurred. After control for baseline age, examination year, body mass index, total cholesterol, smoking, alcohol intake, physical activity, hypertension, diabetes, and parental history of CVD, hazard ratios (95% confidence interval) for CVD deaths across moderate and high categories of CRF (with low fit as referent) were: 0.66 (0.50−0.87) and 0.55 (0.39−0.79), respectively. There was an inverse association between CRF and CVD death among normal-weight (trend p < 0.0001), younger (<60 y, trend p = 0.01), and inactive men (trend p = 0.002). However, no significant association was found between CRF and cancer mortality. Conclusions: Among men with hypercholesterolemia, higher CRF was associated with a lower risk of dying from CVD independent of other clinical risk factors. Our findings underscored the importance of promoting CRF in the primary prevention of CVD in patients with hypercholesterolemia.

The Association of Physical Activity during Weekdays and Weekend with Body Composition in Young Adults.

Physical activity (PA) is a key contributor in long-term weight management but there remains limited research on the association between weekly PA patterns and weight change. The purpose of the present study was to examine the prospective association between weekly PA patterns and weight change in generally healthy young adults. Anthropometric measurements, including dual X-ray absorptiometry, were obtained every 3 months over a period of one year in 338 adults (53% male). At each measurement time, participants wore a multisensor device for a minimum of 10 days to determine total daily energy expenditure and time spent sleeping, sedentary, in light PA (LPA), in moderate PA (MPA), and in vigorous PA (VPA). PA did not differ between weekdays and the weekend at baseline. Twenty-four-hour sleep time, however, was significantly longer during weekends compared to weekdays, which was associated with less time spent sedentary. Weight loss was associated with a significant increase in LPA at the expense of sedentary time during the weekend but not during weekdays. Regression analyses further revealed an inverse association between change in VPA during the weekend and body composition at 12-month follow-up. Taken together, these results suggest that weekend PA plays an important role in long-term weight management.

Subjective Estimation of Physical Activity Using the International Physical Activity Questionnaire Varies by Fitness Level.

BACKGROUND: Subjective measures of moderate and vigorous physical activity (MVPA) rely on relative intensity whereas objective measures capture absolute intensity; thus, fit individuals and unfit individuals may perceive the same activity differently. METHODS: Adults (N = 211) wore the SenseWear Armband (SWA) for 10 consecutive days to objectively assess sedentary time and MVPA. On day 8, participants completed the International Physical Activity Questionnaire (IPAQ) to subjectively assess sitting time and MVPA. Fitness was assessed via a maximal treadmill test, and participants were classified as unfit if the result was in the bottom tertile of the study population by sex or fit if in the upper 2 tertiles. RESULTS: Overall, estimates of MVPA between the IPAQ and SWA were not significantly different (IPAQ minus SWA, 67.4 ± 919.1 MVPA min/wk, P = .29). However, unfit participants overestimated MVPA using the IPAQ by 37.3% (P = .02), but fit participants did not (P = .99). This between-group difference was due to overestimation, using the IPAQ, of moderate activity by 93.8 min/wk among the unfit individuals, but underestimation of moderate activity among the fit participants by 149.4 min/wk. CONCLUSION: Subjective measures of MVPA using the IPAQ varied by fitness category; unfit participants overestimated their MVPA and fit participants accurately estimated their MVPA.