Enhancing endurance performance in mice through apple polyphenol-derived procyanidin and phenolic acid

Abstract

Oral apple polyphenol (AP) administration can enhance muscle strength and endurance. However, apples encompass many polyphenols, and the components contributing to muscle strength and endurance improvements remain unclear. We aimed to elucidate the effects of AP and its components on muscle strength and endurance. Forty male C57BL/6J mice, aged 6 weeks, were randomly assigned to (1) AIN-93G-based normal diet, (2) normal diet supplemented with 2.5 % AP, (3) normal diet supplemented with 1.13 % procyanidins, (4) normal diet supplemented with 0.58 % phenolic acids, and (5) normal diet supplemented with 0.58 % dihydrochalcone groups. Following a 4-week feeding period, grip strength was measured; however, no significant differences occurred among the groups. In contrast, treadmill running capacity to exhaustion significantly increased in the 2.5 % AP, procyanidin, and phenolic acid groups compared to the control group. These findings suggest that the endurance capacity improvement was due to procyanidins and phenolic acids present within the AP components.