Article

Objective: To determine the relationship between change in physical activity
level and change in directly measured maximal aerobic fitness in severely obese
subjects participating in a 1-year lifestyle intervention, and to determine
whether change in 6-min walk test (6MWT) could be used as an indicator of change
in aerobic fitness. Methods: Complete data on aerobic fitness (maximal oxygen
consumption (VO2max) and time to exhaustion on the VO2max test), 6MWT, and
physical activity (Actigraph GT1M accelerometer) were obtained for 21 subjects
(mean age 42.6 years (standard deviation (SD) 11.0 years); mean body mass index
39.6 (SD 4.5) kg/m2). Multiple linear regression (controlling for change in body
mass index) was used to analyse the relationships for: (i) changes in physical
activity vs aerobic fitness and change in 6MWT; and (ii) changes in aerobic
fitness vs 6MWT. Results: Change in physical activity level was related to VO2max
and time to exhaustion (partial r > 0.63, p < 0.003). No significant
relationships were found between changes in aerobic fitness and 6MWT (partial r <
0.22, p > 0.351) or between changes in physical activity level and 6MWT (partial
r = 0.15, p = 0.531). Conclusion: Increased physical activity level over 1 year
resulted in increased aerobic fitness in severely obese subjects. Although the
sample size was small, these results suggest that change in 6MWT might not be a
good indicator of maximal change in aerobic fitness in this population.

Langue : ANGLAIS