Muscle architecture and strength: Adaptations to short-term resistance training in older adults

Abstract

Muscle morphology and architecture changes in response to 6 weeks of progressive resistance training were examined in healthy older adults. In this randomized, controlled design, muscle strength, quality, and architecture were evaluated with knee extension, DEXA, and ultrasound, respectively, in 25 older adults. Resistance training resulted in significant increases in strength and muscle quality of 32% and 31%, respectively. Cross-sectional area of the vastus lateralis increased by 7.4% (p ≤ 0.05). Physiological cross-sectional area (PCSA) of the thigh, a composite measure of muscle architecture, was related significantly to strength (r = 0.57; p ≤ 0.01) and demonstrated a significant interaction after training (p ≤ 0.05). Change in PCSA of the vastus lateralis was associated with change in strength independent of any other measure. Six weeks of resistance training was effective at increasing strength, muscle quality, and muscle morphology in older adult men and women.