Designing Functional Training Programs to Improve Muscle Characteristics in Older Adults Using Electromyography

Aging is accompanied by a gradual loss of functional ability and independence, which has a negative effect on individual quality of life and presents a significant and increasing burden on our society. The age-related loss of muscle mass and strength, also known as sarcopenia, is a major contributor to this loss of functional ability. Older women are particularly susceptible to sarcopenia due to the post-menopausal acceleration in loss of muscle mass. This is reflected by a relatively high rate of falling incidents and concurrent injuries like hip fractures in older women compared to men. Physical exercise is considered to be the most effective way to combat sarcopenia. Muscle plasticity, and therefore the ability to improve strength, appears to be well preserved with age. By improving muscle strength we can improve the functional limits of older adults and increase the reserve capacity for safe performance of everyday tasks. However little is known about the best training type and intensity to improve muscle mass and strength in older adults. Furthermore, training-based adaptations in older adults are often highly task-specific, meaning that improvements strength do not necessarily translate to improvements in functional ability. Evidence from previous intervention studies indicates that training programs for older adults should combine resistance exercise and task-specific exercise to achieve optimal results. However, time-constraints and limited long-term adherence of older adults to resistance exercise present a challenge for designing effective prevention training programs. Bench-stepping is a weight-bearing exercise with high functional similarity to activities of daily life such as stair negotiation. Because it is a weight-bearing exercise that requires vertical displacement of the body's center of mass, it also shows potential for transfer effects on muscle mass and strength. However, previous studies investigating the effects of bench-stepping and stair based exercise have found little to no improvements in muscle mass and strength, likely due to sub-optimal training intensities. Kinetic analyses show that increasing step height beyond heights commonly encountered in daily life results in significant increases in peak power output. This indicates that, by using incremental step heights, bench-stepping could be a viable and task-specific exercise to improve muscle mass and strength. An important factor to take into account is that different muscles