Influence of two strength training modalities (hypertrophy vs. contrast training) on muscular strength, bone health parameters and quality of life in a group of older adults with low skeletal muscle mass index

The main aim of the current study was to compare the effects of two strength training modalities (hypertrophy vs. contrast training) on bone health parameters, physical performance and quality of life in a group of subjects aged 60 and above with low skeletal muscle mass index (SMI). 45 older adults voluntarily participated in this study, but only 41 (22 women and 19 men) completed it. The participants were assigned to 3 different groups: control group (CG; n = 15), contrast training group (CTG; n = 13) and hypertrophy training group (HTG; n = 13). The duration of the training protocol was six months. The experimental groups performed two sessions of strength training per week; the duration of each session was forty-five minutes. Several measurements (which included anthropometrics, body composition, bone parameters, maximal strength parameters, physical performance parameters, fracture risk and quality of life) were performed in the three groups before and after the six-month training period. The different measurements of the protocol were carried out under the same conditions with identical materials and investigators for all the participants and for each approach. The current study has demonstrated that the two training modalities show common benefits such as improving maximal strength, physical performance and quality of life parameters but have no significant effects on bone mineral density (BMD) and bone mineral content (BMC). The influence of training was marked more for improving maximal strength and reducing fracture risk for the contrast training group (who performs movements at high speed) compared to the hypertrophy training group (who performs movements at spontaneous speed). In conclusion, this study shows that both resistance training programs are effective in improving maximal strength, physical performance and quality of life in older adults with low SMI. However, this 6-month intervention was not sufficient to significantly increase BMC nor BMD values in this population.