90 In opposition to traditional resistance training, high-velocity training interventions in older adults have shown positive benefits on physical function. A number of studies have observed improvements in balance100, 101 and 103 and stair climb time,17, 88 and 100 as well as overall physical function.17, 101 and 106 However, it should be noted that in some cases large gains in muscle power translated to small, but significant, gains in physical function.100 In contrast, modest improvements in muscle power conveyed significant improvements in physical function.102 Therefore, the magnitude of improvement in

muscle power is not always proportional to the gains in physical function. XAV-939 purchase One potential explanation for the disproportionate gains in muscle capacity and physical function in the aforementioned studies is the curvilinear

relationship that appears to exist between these two parameters in older adults.17, 27 and 110 Low-functioning individuals may experience exponential gains in physical function as they improve muscle capacity, whereas high-functioning individuals may experience fewer benefits as they are already functioning near optimal levels (e.g., GABA function ceiling effect). Interestingly, a number of intervention studies limited to older women have significantly improved muscle capacity and physical function. Such results have been reported in a variety of populations including healthy community-dwelling,99 breast-cancer survivors,111 pre-frail,112 chronic osteoarthritis,98 and nonagenarian113 older women. Furthermore, strength training interventions as short as 3–6 weeks have effectively increased muscle strength and physical function in older women.86 and 98 In sedentary older women, 6 weeks of strength training resulted in significant gains in muscle strength (23.5%) else and quality (14.8%), and also improved physical function (30-s chair stand (23.8%) and 8-foot up-and-go (−22.4%)). Furthermore, there

was a significant association between changes in muscle quality and improvements in physical function tasks.86 In summary, despite positive results from a few studies, additional research is needed to determine the correlation between change in muscle capacity and change in physical function following a training intervention. Numerous studies have compared the benefits of traditional strength training vs. high-velocity training in older adults. When compared directly, it has been reported that both methods significantly and similarly improve muscle strength and muscle power in healthy community-dwelling adults. 88 Contrastingly, it has also been reported that high-velocity training results in greater gains in muscle power in healthy older adults 114 and older women with self-reported functional limitations. 115 Thus, no consensus has been reached with regard to which method has a greater impact on muscle capacity.