Author(s): WEGNER, M., MÜLLER-ALCAZAR, A., BUDDE, H., Institution: UNIVERSITÄT HAMBURG, Country: GERMANY, Abstract-ID: 2243

Introduction
Physical exercise interventions can cause neuroendocrine activation, which in turn increases salivary testosterone (T) concentrations. Many studies investigating exercise effects have focused on endurance exercise (EE) but not on coordinative exercise interventions (CE). Moreover, seldom research investigate the intraindividual differences related to these two types of exercise. The aim of this study is to examine these effects using an intraindividual comparison. We hypothesized that testosterone concentrations after an acute coordinative exercise would be similar to the testosterone concentrations found after acute endurance exercise of the same intensity and duration, given that in the coordinative exercise condition we expected the cognitive load to be higher compared to the endurance exercise condition.
Methods
Sixty-one students between eighteen and thirty years of age (M = 21.9, SD = 3.2) first completed a coordinative exercise and seven days later an endurance
exercise of the same intensity and length with a maximum heart rate of 64 - 76% (HRmax) over a period of 15 min. Both exercise conditions were performed at the same time of day in the afternoon because of diurnal variation. In order to measure changes in the hypothalamic-pituitary-gonadal axis activity, saliva samples were collected at baseline (t1), and then five and thirty minutes after the exercise (t2 and t3). Age, gender, BMI, and physical activity effects on the pattern of results were checked.
Results
Testosterone levels changed significantly over time, F(2,106) = 10.418, p < .001, eta2 = .164. Compared to baseline, testosterone levels increased shortly after the exercise (t2) and decreased again at t3 with levels being non-different from baseline. There was no difference in testosterone levels regarding the two exercise types, F(2,106) = 0.471, p = .496, eta2 = .009.
Discussion
Testosterone levels increased in both conditions shortly after exercise and decreased again thirty minutes after the exercise to baseline levels. Although slightly lower in cardiovascular demand, the required higher cognitive demands under coordinative exercise lead to comparable release of testosterone when compared to the endurance exercise condition. The results of the study suggest that coordinative exercise could be similarly used for interventions as endurance exercise.