Effects of heavy strength training on performance determinants and performance in cycling and running

This thesis presents data from one large research project resulting in four research papers. The main aim of the project was to examine the effects of adding heavy strength training to female endurance athletes’ normal endurance training on performance in cycling and running, factors affecting performance, and possible mechanisms behind changes in performance and performance determinants. The secondary aim of the thesis was to compare strength related adaptations after a strength-training program between endurance athletes maintaining their normal endurance training and untrained participants. To answer the main research question, nineteen well-trained female duathletes (VO2max cycling: 54 ± 3 ml∙kg-1∙min-1, VO2max running: 53 ± 3 ml∙kg-1∙min-1) were randomly assigned to either normal endurance training (E, n = 8) or normal endurance training combined with strength training (E+S, n = 11). To answer the second research question an additional group consisting of untrained females were recruited (S, n = 10). These participants performed the same strength training program as the athletes in E+S but performed a maximal of one session of endurance training per week. The strength training program consisted of four lower body exercises (3 x 4-10 repetition maximum) twice a week for 11 weeks