MODULE SUPPLEMENT: MUSCULO-SKELETAL SYSTEM
Interventions to Minimize Changes

Loss of muscle strength has been noted to occur at a rate of about 1-2% per year after age 60 (Vandervoort, 2002). Of importance, however, is that a number of changes that occur in muscles with age can be moderated by activity and exercise. Even very late in life, resistance training and endurance exercise can improve muscle mass, muscle strength, and balance, and may increase protein synthesis in the muscle (Williams, et al., 2002). Tai-Chi also has been shown to promote improved balance. Thus it is possible to help older adults stay functional by minimizing deconditioning and maximizing strength training.

Recent studies have shown that measures of lower extremity muscle power, rather than muscle strength, are better predictors of functional performance (Bassey et al., 1992; Suzuki et al., 2001; Bean et al., 2002). Additionally, interventions that target muscle power, such as high-velocity resistance training, have been shown to be more effective in improving peak muscle power and physical function in older adults, with similar gains in muscle strength, compared to a traditional strength training program (Fielding et al., 2002; Miszko et al., 2003).

At the same time, data support the fact that the muscles of older adults may be less effective in adapting to stresses caused by strenuous exercise and less efficient in repairing damage caused by free radicals (McArdle, et al., 2002). This fits with data discussed in the section on Free Radicals in the Theories of Aging discussion (Note: this link will open in a new browser window), but suggests that additional data are needed to refine our understanding of the types and levels of exercise that would be most beneficial for older adults while minimizing the potential for long-term damage.