Investigating the neural adaptations to strength training in older adults

Advancing age is associated with impaired functional ability, which refers to a reduced ability to perform activities of daily living, such as walking, stair climbing, rising from a chair/bed/toilet, or getting in and out of a car. Reduced ability to perform activities of daily living, increases the risk of falls, a loss of independence, and increased mortality. There is extensive data showing that age-related declines in muscle strength, muscle power, rate of force development, gait, balance and muscular endurance are associated with maladaptive plasticity within the motor cortex, a critical region for movement. In young healthy participants, strength training induces plasticity within the motor cortex and is associated with increased muscle strength. However, to date, there have been no studies that have systematically examined whether older adults, who participate in regular strength training, also experience similar levels of plasticity within the motor cortex as young healthy adults do. Understanding the clinical effects of strength training in older adults is important because the ability to activate muscles and produce force is critical for a number of activities of daily living. For example, there is a good correlation that exists between muscle strength and several clinical outcomes such as, gait speed, decreased risk of falls, and better balance; also, people with greater strength levels tend to live longer. In this regard, understanding the neuroplastic changes that occur in the ageing the corticospinal tract following a strength training intervention is important, as it will advance our understanding of the neural adaptations that accompany the increases in muscle strength.