Gender differences in residual effect of prior drop jumps on oxygen uptake during heavy cycling exercise.

BACKGROUND AND OBJECTIVE: Unaccustomed eccentric or eccentric-concentric exercise leaves us stiff and sore the next day and can cause muscle damage. The data about the residual effect of prior eccentric-concentric exercises on oxygen uptake (VO2 ) during constant cycling exercise in women or the data about differences of such effect between genders are scarce. Therefore, the aim of this study was to assess differences of the residual effect of PDJ on VO2 during HCE and indirect muscle damage parameters between women and men.

MATERIALS AND METHODS: The study aimed to asses differences of the residual effect of prior drop jumps (PDJ) on VO2 during heavy cycling exercise (HCE) and indirect muscle damage parameters between men (n=8) and women (n=11). On four different days participants performed one incremental cycling exercise and three HCE (control [CON], 45min [45' PDJ] and 24h [24h PDJ] after 100 drop jumps). The intensity of HCE was set to work rate corresponding to 50% of the difference between the second and the first ventilatory thresholds which were determined analyzing pulmonary gas exchange parameters during incremental cycling exercise. Capillary blood samples were collected in order to measure blood lactate concentration immediately after HCE and serum creatine kinase (CK) activity 24h after PDJ. Subjects rated perceived exertion and delayed onset muscle soreness (DOMS) using 20 and 10 point scales, respectively.

RESULTS: VO2 at 3-6min of HCE performed 45' after PDJ was significantly increased as compared to CON HCE only in the male group. Both men and women felt moderate muscle pain. CK activity was significantly increased 24h after PDJ in the male group. Both during HCE 45' PDJ and 24h PDJ, the significant positive correlation was observed between relative changes of VO2 during steady state of HCE and CK activity only in the male group.

CONCLUSIONS: Prior eccentric-concentric exercise of thigh muscles (100 drop jumps) accelerates VO2 kinetics at the start and increases VO2 during steady state of heavy cycling only in the male group. So, prior exercise of such type has a higher negative impact on cycling economy in men than in women and this might be related to greater muscle damage and fatigue in physically active male persons after plyometric exercise.