Maximal aerobic power, lactate threshold, and running performance in master athletes

Purpose: This study sought to determine how lactate threshold (LT) is relat ed to running performance in older male and female runners, if LT changes s ignificantly with age, and if gender alters the relationship between LT and performance in older runners. Methods: Subjects were 168 master runners (1 11 men, 57 women) selected from a longitudinal study, who ran at least 10 m iles . wk(-1) for 5 yr or more. (V)over dotO(2max) was measured on a treadm ill and body composition by hydrostatic weighing. Blood samples taken each minute of exercise were analyzed for lactate concentration and LT determine d as the breakpoint in lactate accumulation. Performance times and training histories were self-reported by questionnaire. Results: Men had significan tly greater body mass, fat-free mass (FFM), and (V)over dotO(2max) (L . min (-1); mL . kg(-1) min(-1)) than women. FFM and (V)over dotO(2max) (L . min( -1); mL . kg(-1). min(-1)) declined with age in both men and women. Running performance was significantly different between men and women and declined with age in both. LT (L . min(-1); mL . kg(-1). min(-1)) was significantly different between men and women, and declined significantly with age in me n, whereas LT (%(V)over dotO(2max)) did not differ between men and women an d increased significantly with age in both. (V)over dotO(2max) (mL . kg(-1) . min(-1)) was the most significant predictor of performance in both men an d women, whereas LT (L . min(-1)) added to the prediction of 5-km and 10-km performance in women. Conclusion: The results of this study demonstrate th at (V)over dotO(2max) (mL . kg(-1) min(-1)) is a better predictor of perfor mance than LT in older male and female runners. Additionally, LT as a perce ntage of (V)over dotO(2max) increases significantly with age.