Current knowledge of the physiological, biomechanical, and sensory eVects of the cycle to run transition in the Olympic triathlon (1.5 km, 10 km, 40 km) is reviewed and
implications for the training of junior and elite triathletes are discussed. Triathlon running elicits hyperventilation, increased heart rate, decreased pulmonary compliance, and exercise induced hypoxaemia. This may be due to exercise intensity, ventilatory muscle fatigue, dehydration, muscle fibre damage, a shift in metabolism towards fat oxidation, and depleted glycogen stores after a 40 km cycle. The energy cost (CR) of running during the cycle to run transition is also increased over that of control running. The increase in CR varies from 1.6% to
11.6% and is a reflection of triathlete ability level. This increase may be partly related to kinematic alterations, but research suggests that most biomechanical parameters are
unchanged. A more forward leaning trunk inclination is the most significant observation reported. Running pattern, and thus running economy, could also be influenced by sensorimotor perturbations related to the change in posture. Technical skill in the transition area is obviously very important. The conditions under which the preceding cycling section is performed - that is, steady
state or stochastic power output, drafting or non-drafting-are likely to influence the speed of adjustment to transition. The extent to which a decrease in the average 10
km running speed occurs during competition must be investigated further. It is clear that the higher the athlete is placed in the field at the end of the bike section, the greater the importance to their finishing
position of both a quick transition area time and optimal adjustment to the physiological demands of the cycle to run transition. The need for, and current methods of, training
to prepare junior and elite triathletes for a better transition are critically reviewed in light of the eVects of sequential cycle to run exercise.