Whole-body vibration slows the acquisition of fat in mature female rats

Objective: To evaluate the effects of whole-body vibration on fat, bone, leptin and muscle mass. Methods/Design: Thirty 7-month-old female 344 Fischer rats were randomized by weight into three groups ( baseline, vibration or control; n=8-10 per group). Rats in the vibration group were placed inside individual compartments attached to a Pneu-Vibe vibration platform (Pneumex, Sandpoint, ID, USA) and vibrated at 30-50 Hz (6mm peak to peak) for 30 min per day, 5 days per week, for 12 weeks. The vibration intervention consisted of six 5-min cycles with a 1-min break between cycles. Results: There were significant body composition differences between the whole-body vibration and the control group. The whole-body vibration group weighed approximately 10% less (mean +/- s.d.; 207 +/- 10 vs 222 +/- 15 g, P<0.03) and had less body fat (20.8 +/- 3.8 vs 26.8 +/- 5.9 g, P<0.05), a lower percentage of body fat (10.2 +/- 1.7 vs 12 +/- 2.0%, P<0.05), and lower serum leptin levels (1.06 +/- 0.45 vs 2.27 +/- 0.57 ng ml(-1), P<0.01) than the age-matched controls. No differences were observed for total lean mass, bone mineral content (BMC), bone mineral density (BMD), insulin-like growth factor-I (IGF-I) or soleus ( SOL) and extensor digitorum longus (EDL) mass or function. Regional high-resolution dual-energy X-ray absoptiometry scans of the lumbar spine (L1-4) revealed that the whole-body vibration group had significantly greater BMC (0.33 +/- 0.05 vs 0.26 +/- 0.03 g, P<0.01) and BMD (0.21 +/- 0.01 vs 0.19 +/- 0.01 g cm(-2), P<0.01) than the control group. No differences between the groups were observed in the amount of food consumed. Conclusion: These findings show that whole-body vibration reduced body fat accumulation and serum leptin without affecting whole body BMC, BMD or lean mass. However, the increase in vertebral BMC and BMD suggests that vibration may have resulted in local increases in bone mass and density. Also, whole-body vibration did not affect muscle function or food consumption.