15 November 2019
Training Conflicts Fitness is complex! It involves a complex blend of strength and endurance, both muscular and aerobic. At different levels of intensity, the muscles utilise different fuel mechanisms. You have different types of muscle fibre in each muscle; some deliver explosive power, while others can supply a moderate level of power over extended periods. As an endurance athlete racing for more than about 2 hours your body will have to get good at using fat rather than glycogen and blood sugar as its source of energy.