Background: The purpose of this study was to investigate the beneficial effects that sedentary behavior modification has on obesity and metabolic syndrome among obese women who participated in a 12 week exercise intervention program.
Methods: A total of 38 women voluntarily participated in a 12-week exercise intervention program. The intervention included treadmill aerobic exercise, circuit weight training, stretching and sedentary behavior odification, which was done by reducing sitting time during postprandial periods. Primary outcomes including body fat, physical fitness, and metabolic risk factors were measured prior to and after the intervention. After completion of the intervention, the subjects were classified into one of the following three groups; those who were in the high 25 percentile (n = 10, HIGH group) of reduced sitting time, those who were in the middle 50 percentile (n = 18, MID group), and those in low 25 percentile (n = 10, LOW group).
Results: Participating in the 12-week exercise intervention resulted in significant decreases in body weight, body mass index, percent body fat, waist circumference, and metabolic risk factors. Improved parameters of body fat were proportionally and significantly associated with the amount of reduced sitting time since the greatest improvements were found in the HIGH group, which were
followed by those of the MID and LOW groups.
Conclusions: The findings of the study suggest that reduced sitting time can play a critical role in magnifying the beneficial effects of a combined exercise program on obesity and metabolic risk factors.

Keywords: Exercise training, Sitting time, Obesity, Metabolic syndrome

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