Moderate intensity swimming training on bone mineral density preservation under food restriction in female rats

Abstract

Aim:

To investigate the effect of moderate-intensity swimming training on bone mineral density under a 20% food restriction (FR) schedule for 12 weeks in female rats.

Methods:

Forty female Wistar rats were distributed into four groups: control (CG), exercised (EG), food restriction (FRG), and food restriction/exercised (FREG). At 95 days, the animals were subjected to aquatic adaptation and then performed the critical load test to individually determine the critical load intensity (CLi, % of body mass). Exercised groups swam 5 days a week, 30 minutes daily with weekly adjustment of the load equivalent to 80% of the CLi. The FR schedule was 20% in relation to CG and started concomitantly with physical training (PT). After 12 weeks, visceral fat weight was recorded and the femur was collected for biophysical and biomechanical analysis.

Results:

FR and exercise training promoted visceral fat reduction (p<0.01). FR reduced bone mineral density (p<0.01), while exercise training prevented such reduction. On the other hand, FR and exercise training did not promote significant changes in biomechanical parameters of the femur.

Conclusion:

Exercise training at moderate intensity was efficient in preserving bone mineral density despite long term of FR at 20%.

Keywords:
aerobic exercise; bone tissue; energy restriction; adipose tissue