Specificity of physiological adaptation to endurance training in distance runners and competitive walkers

Summary The present study was designed to evaluate the specificity of physiological adaptation to extra endurance training in five female competitive walkers and six female distance runners. The mean velocity () during training, corresponding to 4 mM blood lactate [onset of blood lactate accumulation (OBLA)] during treadmill incremental exercise (training was 2.86 m·s^–1 SD 0.21 in walkers and 4.02 m·s^–1, SD 0.11 in runners) was added to their normal training programme and was performed for 20 min, 6 days a week for 8 weeks, and was called extra training. An additional six female distance runners performed only their normal training programme every day for about 120 min at an exercise intensity equivalent to their lactate threshold (LT) (i.e. a running of about 3.33 m·s^–1). After the extra training, there were statistically significant increases in blood lactate variables (i.e. oxygen uptake (O₂) at LT, at LT, O₂ at OBLA, at OBLA; P<0.05), and running F for 3,000m (P<0.01) in the running training group. In the walking training group, there were significant increases in blood lactate variables (i.e., at LT, at OBLA; P<0.05), and walking economy. In contrast, there were no significant changes in lactate variables, running and economy in the group of runners which carried out only the normal training programme. It is suggested that the changes in blood lactate variables such as LT and OBLA played a role in improving F of both the distance runners and the competitive walkers. Furthermore, the significant improvement in walking economy brought about by extra endurance training might be a specific phenomenon for competitive walkers compared to runners.