Effect of two different volumes of resistance training on serum level of fibroblast growth factor-21, body fat percentage and mobility in obese elderly women

Fibroblast growth factor 21 (FGF21) increases lipolysis and fatty acid oxidation. The effect of different volumes of resistance training on FGF21 is not well defined. Therefore, the aim of this study was to compare the effects of high and low volume of resistance trainings on serum level of FGF-21, body composition and mobility in sedentary obese older women.

Thirty sedentary obese elderly women (age 64.57±4.50 years, body mass index 32.34±2.69 kg/m2, and body fat percent 40.93±2.11) who were resident in Mashhad participated in this quasi-experimental study. The subjects were randomly assigned into three equal groups of control, low volume resistance training (LVRT), and high volume resistance training (HVRT). The subjects performed LVRT (one-set) and HVRT (three-set) protocols twice weekly for 12 weeks. Anthropometric and biochemical evaluations were carried out one week before the first session and 48 hours after the last session. In addition, 30-second chair stand, arm curl, two minutes step and eight foot up-and-go tests were evaluated. Dependent t-test and analysis of covariance were used to examine the intra- and inter-group differences, respectively.

Following training, the body fat percentage was significantly lower in HVRT group than LVRT group (P=0.001). In contrast, the results in 30-second chair stand (P=0.001) and arm curl (P=0.001) were significantly higher in HVRT group than LVRT group. However, there were no significant differences between two groups of HVRT and LVRT in weight (P=0.999), body mass index (P=0.999), FGF21 (P=0.999), two minutes step (P=0.072), and eight foot up-and-go (P=0.231) at the end of the protocols.

These results demonstrate that three-set resistance training resulted in greater improvements in body composition and mobility than single-set resistance training in obese elderly women.