LE3 .A278 2023

2023

Murphy, René

Acadia University

Bachelor of Kinesiology

Honours

Kinesiology

Kinesiology

Sarcopenia is the progressive loss of skeletal muscle mass, quality, and strength with advanced aging, and disproportionality effects post-menopausal women. In the United States alone, health care costs associated with sarcopenia totalled as high as $18.5 billion (USD) per year. Sarcopenia is associated with several negative psychological and physical health effects, with chronic resistance exercise being prescribed as the main non-pharmacological means by which to mitigate its effects. Additionally, with its hypertrophic effects, gains in knee extensor strength, prolonged muscle protein synthesis response, and tolerability to the older adult population, low-load high-repetition resistance exercise is becoming more common. It is therefore pertinent to understand the acute effects of a single bout of exercise under such conditions. Any transient decrements in physical functioning, such as reductions in strength and power of the lower body and gait alterations can increase the potential risk of falls in older adults, affecting their ability to successfully perform activities of daily living. This study sought to determine leg extensor torque, power production, walking kinetics, and standing balance in the three days following a low-load high-repetition lower body resistance exercise protocol in older women 65+ years. The exercise protocol consisted of three sets of leg press and leg extension at 30% of 1RM until failure. Leg extensor dynamometry (maximum voluntary contractions and isotonic contractions) assessed strength and power. Standing balance was measured using center of pressure velocity and walking measures of balance were recorded using step length and step width. No significant diminishments in strength or power were observed. Changes in center of pressure velocity (P <0.001) and step length and width (P <0.001) were statistically significant 24 h post exercise. It was observed that older women experienced reductions in standing and walking balance 24 h post low-load high-repetition resistance exercise, which may potentially increase risk of falls and negatively affect habitual activities.

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https://scholar.acadiau.ca/islandora/object/theses:3969