R and omized controlled trials found a positive correlation for SB with BMI , neck circumference , fat mass , HbA1C , cholesterol and insulin levels , cohort studies additionally for WC , leptin , C-peptide , ApoA1 and Low density lipoprotein and a negative correlation for HDL .
Most studied biomarkers associated with SB were of cardiovascular or metabolic origin .
OBJECTIVE Pathomechanisms of sedentary behaviour ( SB ) are unclear .
We conducted a systematic review to investigate the associations between SB and various biomarkers in older adults .
Vitamin d and physical activity status: associations with five-year changes in body composition and muscle function in community-dwelling older adults.
CONTEXT High vitamin D and physical activity ( PA ) levels are independently associated with improved body composition and muscle function in older adults . OBJECTIVE The objective of this study was to investigate the interaction of 25-hydroxyvitamin D ( 25OHD ) and PA status in maintenance of body composition and muscle function in older adults . DESIGN AND SETTING This was a 5-year prospect i ve population -based study of Australian community-dwelling older adults . PARTICIPANTS Participants in the study included 615 community-dwelling volunteers aged 50 years old or older [ 61.4 ± 6.9 ( mean ± SD ) y ; 48 % female ] r and omly selected from electoral rolls and categorized according to baseline serum 25OHD ( ≥ or < 50 nmol/L ) and PA ( ≥ or < 10,000 pedometer determined steps/d ) levels as follows : high 25OHD and high PA ( VitD+PA+ ) ; high 25OHD and low PA ( VitD+PA- ) ; low 25OHD and high PA ( VitD-PA+ ) ; and low 25OHD and low PA ( VitD-PA- ) . A subset of 518 participants completed accelerometer assessment s during follow-up . MAIN OUTCOME MEASURES Changes in dual-energy X-ray absorptiometry-assessed body composition and lower-limb muscle function were measured . RESULTS VitD+PA+ had significantly smaller increases in body fat over 5 years compared with other groups ( all P < .05 ) . Higher baseline pedometer-determined PA result ed in declines in total body fat ( β = -.23 kg per 100 steps/d , P = .001 ) over 5 years for participants with high 25OHD but not those with low 25OHD ( P > .05 ) . Among participants with accelerometer data , these associations were generally mediated by higher levels of moderate/vigorous PA . CONCLUSIONS High vitamin D status appears to enhance PA-related declines in body fat during aging , but the mechanism may be greater amounts of outdoor moderate/vigorous PA rather than a direct effect of 25OHD
R and omized controlled trials found a positive correlation for SB with BMI , neck circumference , fat mass , HbA1C , cholesterol and insulin levels , cohort studies additionally for WC , leptin , C-peptide , ApoA1 and Low density lipoprotein and a negative correlation for HDL .
Most studied biomarkers associated with SB were of cardiovascular or metabolic origin .
OBJECTIVE Pathomechanisms of sedentary behaviour ( SB ) are unclear .
We conducted a systematic review to investigate the associations between SB and various biomarkers in older adults .