Research Paper Title

Effect of Protein Supplementation Combined with Resistance Training on Muscle Mass, Strength and Function in the Elderly: A Systematic Review and Meta-Analysis.

Background

The loss of muscle mass, strength and function associated with increasing age has various health ramifications, including the elevated risk for falls, fractures, frailty, poor quality of life, and mortality. Several studies have confirmed the effects of protein supplementation and RT (resistance training) for this age-related change independently, but whether a combination of the two produces a stronger effect remains controversial.

This study aimed to explore whether a combination of protein supplementation and RT leads to reduction of muscle mass, strength and function in the elderly.

Methods

The researchers retrieved RCTs (randomised controlled trials) reporting the effects of protein supplementation combined with RT on muscle mass, strength and function in the elderly, published before May 2018 through PubMed, MEDLINE, Embase, and manual searches.

Results

Twenty-one RCTs were included, involving 1,249 participants. The results showed that protein supplementation combine with RT significantly enhances the muscle mass and strength of the older adults, where FFM (fat-free mass) increased by 0.23 kg (95% CI: 0.09, 0.38; P=0.002), ASMM (appendicular skeletal muscle mass) by 0.39 kg (95% CI: 0.14, 0.64; P=0.002), handgrip strength by 0.29 kg (95% CI: 0.08, 0.50; P=0.008), knee extension strength by 0.27 kg (95% CI: 0.06, 0.47; P=0.013), leg press strength by 0.33 kg (95% CI: 0.01, 0.64; P=0.04), but no significant effects were seen on muscle function.

Conclusions

Compared to simple RT, protein supplementation combined with RT is more effective in enhancing the muscle mass and strength in the elderly, and the findings do not support the benefit of combination treatment for muscle function.

Reference

Hou, L., Lei, Y., Li, X., Huo, C., Jia, X., Yang, J., Xu, R. & Wang, X. (2019) Effect of Protein Supplementation Combined with Resistance Training on Muscle Mass, Strength and Function in the Elderly: A Systematic Review and Meta-Analysis. The Journal of Nutrition, Health, and Aging. 23(5), pp.451-458. doi: 10.1007/s12603-019-1181-2.