Long-term effects of exercise and amino acid supplementation on muscle mass, physical function and falls in community-dwelling elderly Japanese sarcopenic women: A 4-year follow-up study.

AIM

To determine the long-term effects of interventions carried out for the improvement of muscle mass, strength, walking ability and fall rate, 4 years after the completion of the intervention.

METHODS

Out of 304 elderly sarcopenic women aged over 75 years, 155 participated in an intervention and 149 were excluded from the intervention. Those excluded were considered as non-participants and included in the analysis. Follow-up data were available for 259 women (135 intervention participants; 124 non-participants). Muscle mass was determined by bioelectrical impedance analysis. Physical fitness measurements and interview surveys were carried out at baseline and at 4-year follow up.

RESULTS

Compared with the non-participants, women in the intervention group had significantly smaller reductions in measures of muscle mass, strength and walking speed from baseline to follow up. The absolute mean difference between the two groups was 3.7% (95% confidence interval -6.5 to -0.8; P = 0.012) for leg muscle mass, 10.7% (-21.0 to -0.3; P = 0.011) for knee extension strength and 8.4% (-16.0 to -0.9; P = 0.029) for usual walking speed. Instrumental activities of daily living disability significantly increased in both participants and non-participants in 4 years. The fall rate of the previous 1 year in intervention participants was 18.5% in 2008 and 23.0% in 2012 (χ(2)  = 2.122, P = 0.145), and 17.7% in 2008 and 29.0% in 2012 among non-participants (χ(2)  = 15.415, P < 0.001).

CONCLUSION

Participation in an intervention could prevent significant declines in lower extremity muscle mass, strength and mobility, even in the long-term, and might be beneficial in suppressing otherwise significant rises in fall rates.