​Explosive-strength Training Improves 5-km Running Time by Improving Running Economy and Muscle Power

Explosive-strength Training Improves 5-km Running Time by Improving Running Economy and Muscle Power

Incorporating a specific type of strength training, explosive-strength training into a endurance oriented individual may enhance neural adaptations, such as motor unit recruitment. Though VO2max, is commonly used to predict endurance performance, running economy (RE), and motor unit recruitment are anaerobic characteristics that may further differentiate well-trained endurance athletes. Previous literature demonstrates that heavy resistance training has been shown to increase endurance performance in untrained individuals. Paavolainen et al., 1999 investigated the responses and adaptations of explosive-strength training incorporated with endurance training on 5-km running performance, aerobic power, RE, several neuromuscular parameters, and overall muscle power.

Participants were divided into an experimental group (E) consisting of 10 and a control group (C) of 8 individuals, with no less than 5 years of experience. Using a 9-wk training protocol, combining sprints and explosive-based exercises with cross country or road running (<84%) and similar circuit training regimens of abdominal and leg exercises. The results indicated a decreased 5km run time, a decreased contact time, and constant velocity per lap also had significantly decreased after training. Also significant group-by-training were found in RE and Vmart, and VO2max-demand. Contrary, only the C group had presented an increase in VO2max when compared with group E.

When analyzing the training regiment, the researchers employed maximal velocity contractions with limited weight bearing activity. Though aiming to assess both aerobic and anaerobic characteristics, the utilization of heavier loads may have attenuated these responses. Incorporating more strength training related exercises for these highly trained endurance athletes may have also demonstrated elevated differences between groups. As explained in the discussion portion, it seemed the explosive-training protocol did not seem to have a significant effect on endurance performance. Possibly incorporating more strength training sessions per week, could have presented greater effects but with the limitation that endurance performance could decrease as a result.

The parameters assessed, were crucial and appropriate for the intended anaerobic-related adaptations. The investigators also clarified that EMG activity was not recorded, which could lend greater understanding into the proposed neurological adaptations.  Along with assessing the difference of the characteristics, analyzing correlations between differing adaptations allowed for researchers to support and propose reasoning behind their hypothesis.