| Sarcopenia is believed to play a principal role in the pathogenesis of frailty and functional impairment that may occur with old age, as well as to serve as a contributing risk factor for numerous other disease processes. There is strong evidence to suggest that sarcopenia is a reversible cause of disability, and that aging persons with early sarcopenia are probably the most likely to benefit from exercise interventions. For the current investigation, meta-analysis procedures were implemented to determine the treatment effect of progressive resistance training for muscular strength and lean body mass (LBM) in elderly populations. All progressive resistance training intervention studies which had a comparison group, and that included one or both primary outcomes related to LBM or muscular strength, were included in the original article acquisition. Subsequent coding and elimination of articles, as well as the analyses of data followed rigorous procedures. Data were pooled from a total of 97 eligible articles, representing over 2,400 subjects. The mean adjusted effect size for progressive resistance training-induced increases in lean body mass was considered to be of minimal effect. Conversely, the mean adjusted effect size for muscular strength was considered to be of moderate effect. Greater strength gains were demonstrated among subjects in the youngest age category, than any of the other groups. For specific strength training variables, weekly volume, intensity, and frequency emerged as significant independent moderators, and each were characterized by a distinct dose-response relationship. The results of the current investigation demonstrate that progressive resistance training is very effective for eliciting muscular strength adaptation among elderly subjects, despite a respective trivial effectiveness for eliciting significant increases in whole body lean mass. These findings and subsequent dose-response relationships may be considered a viable treatment option for individuals experiencing age-related functional declines. Specifically, for individuals experiencing such declines, progressive resistance training may serve as a superior modality over other forms of physical activity to augment force production capacity and potentially minimize further diminution of whole body lean mass. |
