Isometric Knee Extension and Hip Abduction Strength Are Negatively Correlated With Age in Female Recreational Runners

Running mitigates age-related changes in cardiovascular fitness, but running alone does not preserve muscle strength in aging adults. In addition to age-related declines in muscle strength, menopause negatively affects muscle strength in females. However, the effects of aging on muscle strength in female runners has not been well studied. The purpose of this study was to determine the relationship between age and lower-extremity muscle strength in healthy female recreational runners. Peak isometric and isokinetic (concentric and eccentric) strength of the hip abductors, hip extensors, knee extensors, and plantar flexors was tested in 54 participants (ages 27–65 years) using an isokinetic dynamometer. Simple correlation was used to determine the relationship between age and muscle strength. There was a significant negative correlation between age and isometric hip abduction strength (R = −.32, p = .017) and age and isometric knee extension strength (R = −.28, p = .041). There were no significant correlations between age and any other measures of isometric or isokinetic strength. Interventions to improve hip abduction and knee extension strength may be beneficial in aging female runners. Running may help mitigate some age-related declines in concentric muscle strength in female runners. Several strength measures were weakly to moderately correlated with running pace. Efforts to maintain lower-extremity muscle strength into older age may mitigate age-related declines in running pace.