Comparing Vascular Responses to Resistance Exercise with and Without Blood Flow Restriction in Young and Older Adults

Aging leads to declines in functional capacity and effort tolerance. Muscle strength remains stable from ages 25 to 50 but declines significantly after age 60, affecting activities like stair climbing and walking, reducing autonomy and independence. While muscle atrophy is a significant factor, macrovascular endothelial dysfunction also impairs skeletal muscle performance in older adults. Nitric oxide (NO), produced by endothelial cells, regulates vascular homeostasis and contractile function. NO enhances muscle fiber shortening velocity, reduces twitch time-to-peak contraction, and increases the rate of force development. Aging-related endothelial dysfunction reduces NO availability, leading to reduced muscle mass and sarcopenia via decreased skeletal muscle perfusion. Increased arterial stiffness disrupts ventricular-vascular coupling, reducing cardiac output and contributing to age-re