Exercise training increases intramyocellular lipid and oxidative capacity in older adults
Related Experiment Video
Updated: Aug 23, 2026

Improving Strength, Power, Muscle Aerobic Capacity, and Glucose Tolerance through Short-term Progressive Strength Training Among Elderly People
Published on: July 5, 2017
Ryan Pruchnic1, Andreas Katsiaras, Jing He
1Dept. of Medicine, University of Pittsburgh Medical Center, 3459 Fifth Ave., Pittsburgh, PA 15213, USA.
Abstract:
Intramyocellular lipid (IMCL) has been associated with insulin resistance. However, an association between IMCL and insulin resistance might be modulated by oxidative capacity in skeletal muscle. We examined the hypothesis that 12 wk of exercise training would increase both IMCL and the oxidative capacity of skeletal muscle in older (67.3 +/- 0.7 yr), previously sedentary subjects (n = 13; 5 men and 8 women). Maximal aerobic capacity (Vo(2 max)) increased from 1.65 +/- 0.20 to 1.85 +/- 0.14 l/min (P < 0.05), and systemic fat oxidation induced by 1 h of cycle exercise at 45% of Vo(2 max) increased (P < 0.05) from 15.03 +/- 40 to 19.29 +/- 0.80 (micromol.min(-1).kg fat-free mass(-1)). IMCL, determined by quantitative histological staining in vastus lateralis biopsies, increased (P < 0.05) from 22.9 +/- 1.9 to 25.9 +/- 2.6 arbitrary units (AU). The oxidative capacity of muscle, determined by succinate dehydrogenase staining intensity, significantly increased (P < 0.05) from 75.2 +/- 5.2 to 83.9 +/- 3.6 AU. The percentage of type I fibers significantly increased (P < 0.05) from 35.4 +/- 2.1 to 40.1 +/- 2.3%. In conclusion, exercise training increases IMCL in older persons in parallel with an enhanced capacity for fat oxidation.
Related Concept Videos
Exercise and Muscle Performance
Endurance exercises
Endurance exercises involve running, swimming, or cycling, which require repetitive movements with low force output. When a person engages in endurance exercise, a few noticeable changes occur in their skeletal muscles. For instance, the number of capillaries...
Exercise and Cardiac Output
Sustained exercise increases the muscles' oxygen demand, which can be met...
Exercise and Cardiovascular Response
Light to moderate physical activity initiates a series of interconnected responses in the body. The heart rate modestly increases in anticipation of the workout, followed by widespread vasodilation as oxygen consumption by skeletal muscles increases. This results in decreased peripheral resistance, increased capillary blood flow, and accelerated...
Mitochondria
Muscle Recovery and Fatigue
The Effect of Aging on Tissues
