Differences in fat loss in response to physical activity among severely obese men and women
Sammanfattning
Background: Direct measurement of physical activity may be critical to revealing its relationship
with the change in fat mass over time. The aim of this study was to determine the relationship
between accelerometer-determined change in physical activity and change in fat mass in severely
obese men and women.
METHODS: A total of 49 severely obese men (n = 12) and women (n = 37) (mean age 42.8 years
(standard deviation (SD) 9.6); mean body mass index 42.0 kg/m2 (SD 5.9) participated in a 1-year
lifestyle intervention with 4 measurements of physical activity (Actigraph GT1M accelerometer),
energy intake (180-item food frequency questionnaire), and body composition. Associations were
determined using linear regression analyses.
RESULTS: In the total group change in both duration and intensity of physical activity were
independently related to change in fat mass (partial r = -0.38 to -0.31, p = 0.001-0.007) after
adjustment for baseline body weight, gender and change in energy intake. A gender-specific effect of
change in physical activity duration was found for change in fat mass (p for change in physical
activity duration*gender < 0.001), where the association was significant in men (partial r = -0.53, p <
0.001), but not in women (partial r = -0.17, p = 0.149).
CONCLUSION: Increased intensity of physical activity was associated with loss of fat mass in
severely obese men and women, whereas physical activity duration was associated with fat mass
loss in men.