Grant: Travel Awards - Institute Community Support

Background: It is believed that normal aging is associated with a progressive loss of muscle mass, strength and quality thereby reducing quality of life and increasing the risk of falls, fractures and functional disabilities in the elderly. The increasing number of persons aged over 65 years old worldwide imposes a high burden on health care services and costs. Hence, we sought to find a strategy that could limit loss of muscle mass, strength and quality during aging. One of these strategies is throughout practicing physical activity to reduce or at least stabilize decline of muscle function. Thus, the aim of this study is to investigate the role of voluntary and regular physical activity on muscle function in elderly active men compared to young active men. Methods: Eleven young (24 ± 3 years) and 10 old (72 ± 4 years) men were recruited. They were practicing regular physical activity for the last 5 years. Lean body mass, fat mass and knee extension strength were assessed. Muscle composition was assessed by Magnetic Resonance Imaging and muscle biopsies were collected in the Vastus Lateralis. Results: Both groups had the same level and type of physical activity. Total, leg and appendicular (legs + arms) lean body mass were lower in the elderly group. Similarly, knee extension strength was also lower in this group. However, there was no difference in relative muscle strength and muscle quality indexes between our two groups. Conclusion: Our results indicate that muscle quality and its related observed factors are maintained with age, except for absolute muscle mass and strength. As previously stated in numerous studies muscle quality indexes are considered as the best predictors of functional capacity in the elderly. Therefore, our results support that adopting a lifestyle that includes regular physical activity for at least 5 years could counteract muscle function decline during aging.