Adiposity and Age Explain Most of the Association between Physical Activity and Fitness in Physically Active Men

Abstract

BackgroundTo determine if there is an association between physical activity assessed by the short version of the International Physical Activity Questionnaire (IPAQ) and cardiorespiratory and muscular fitness.Methodology/Principal FindingsOne hundred and eighty-two young males (age range: 20–55 years) completed the short form of the IPAQ to assess physical activity. Body composition (dual-energy X-Ray absorptiometry), muscular fitness (static and dynamic muscle force and power, vertical jump height, running speed [30 m sprint], anaerobic capacity [300 m running test]) and cardiorespiratory fitness (estimated VO2max: 20 m shuttle run test) were also determined in all subjects.Activity-related energy expenditure of moderate and vigorous intensity (EEPAmoderate and EEPAvigorous, respectively) was inversely associated with indices of adiposity (r = −0.21 to −0.37, P<0.05). Cardiorespiratory fitness (VO2max) was positively associated with LogEEPAmoderate (r = 0.26, P<0.05) and LogEEPAvigorous (r = 0.27). However, no association between VO2max with LogEEPAmoderate, LogEPPAvigorous and LogEEPAtotal was observed after adjusting for the percentage of body fat. Multiple stepwise regression analysis to predict VO2max from LogEEPAwalking, LogEEPAmoderate, LogEEPAvigorous, LogEEPAtotal, age and percentage of body fat (%fat) showed that the %fat alone explained 62% of the variance in VO2max and that the age added another 10%, while the other variables did not add predictive value to the model [VO2max = 129.6−(25.1× Log %fat) − (34.0× Log age); SEE: 4.3 ml.kg−1. min−1; R2 = 0.72 (P<0.05)]. No positive association between muscular fitness-related variables and physical activity was observed, even after adjusting for body fat or body fat and age.Conclusions/SignificanceAdiposity and age are the strongest predictors of VO2max in healthy men. The energy expended in moderate and vigorous physical activities is inversely associated with adiposity. Muscular fitness does not appear to be associated with physical activity as assessed by the IPAQ.

Androgen Receptor Gene Polymorphisms and the Fat‐Bone Axis in Young Men and Women

“…Whole‐body composition was assessed by DXA (QDR‐1500, software version 7.10; Hologic Corp, Waltham, Massachusetts) as previously reported (Perez‐Gomez et al, 2008). Upper and lower limb lean mass (kg) was calculated from regional analysis of the whole body scan (Sanchís‐Moysi et al, 2009; Serrano‐Sanchez et al, 2010), which gives a valid and a reliable estimate of muscle mass in the extremities (Kim et al, 2002).…”

“…Therefore, osteocalcin may act as a confounder, masking a potential relationship between AR polymorphism and fat mass phenotype in humans. Likewise, physical activity and fitness (Nielsen et al, 2010; Serrano‐Sanchez et al, 2010; Wang et al, 2010) may also influence the relationship between AR polymorphism and the fat mass phenotype.…”

Skeletal muscle signaling response to sprint exercise in men and women

“…The body composition of each subject was determined by DXA (Hologic QDR-1500, Hologic Corp., software version 7.10, Waltham, MA) as described elsewhere (PerezGomez et al 2008;Serrano-Sanchez et al 2010). Then, subjects reported to the laboratory on two different days to perform familiarization Wingate tests (Monark 818E, Monark AB, Vargerg, Sweden).…”

Tai Chi Is a Promising Exercise Option for Patients With Coronary Heart Disease Declining Cardiac Rehabilitation

“…Finally, aerobic fitness did not improve despite improvements in overall PA. This finding is not surprising, given that several factors, including, among others, heritability, age and adiposity, and smoking, influence aerobic fitness in addition to PA.…”

“…Finally, aerobic fitness did not improve despite improvements in overall PA. This finding is not surprising, given that several factors, including, among others, heritability, 59 age and adiposity, 60 and smoking, 61 influence aerobic fitness in addition to PA. Our work has several important strengths. First, this was the first study to examine the effect of tai chi on objectively measured PA. Second, we were able to enroll a communitybased sample of severely deconditioned, high-risk patients who had declined enrollment in CR.…”