Effects of Overload Eccentric and Concentric Resistance Training on the Cost of Walking, Muscle-tendon and Jumping Performance in Healthy Older Individuals

Normal aging leads to a decline in neuromuscular and mobility functions, including a 60% reduction in maximal voluntary force production, a 25% decrease in muscle volume and quality (sarcopenia), and reduced tendon stiffness by age 70. These changes impair walking speed, balance, and increase the metabolic cost of walking by \~20% in older adults compared to younger individuals. While walking training can reduce metabolic costs, no interventions have successfully addressed the 20% age-related difference. Resistance training, particularly eccentric (muscle-lengthening) training, shows promise for improving muscle strength and mass, but its effects on functional, cognitive abilities, and walking economy in older adults remain unexplored.