STØREN, ØYVIND; HELGERUD, JAN; STØA, EVA MARIA; HOFF, JAN
Endurance performance in long-distance running, lasting approximately 7-150 min, is 80-99% dependent on aerobic metabolism. Interindividual variance in aerobic endurance performance in running is dependent on the three factors: maximal oxygen consumption (VO2max), lactate threshold(LT), and running economy (RE). RE is commonly defined as the steady-rate VO2 measured as mL·kg−1·min−1 at a standard velocity or in mL·kg−1·m−1. Strength training has been associated with interfering or inhibiting endurance development. On the other hand, endurance training performed without concurrent strength training has been reported to impair strength and vertical jumping height. When combining strength and endurance training, several studies have reported improved RE.
The term maximal strength training (MST) has been used to describe strength training using high loads, few repetitions, and emphasis on neural adaptations to strength enhancement rather than muscular hypertrophy. In an recent publication, an improvement in maximal strength of 28% improved work efficiency by 32% in a group of Chronic Obstructive Pulmonary Disease patients. Similar MST interventions have been used for competitive cross-country skiers in double poling, showing an improvement in work economy of 9% to 27%.
The aim of this study is thus to assess to which extent MST with emphasis on neural adaptations, supposedly not increasing body mass, as a supplement to endurance training will affect RE among well-trained, long-distance runners. The hypothesis is that MST performed as half- squats, and as a supplement to endurance training, will improve 1RM, rate of force development (RFD), RE, and time to exhaustion at maximal aerobic speed (MAS).
The intervention manifested significant improvements in 1RM (33%), RFD (26%), RE (5%), and time to exhaustion at MAS (21%). No changes were found in maximal oxygen uptake or body weight. The control group exhibited no changes from pre to post values in any of the parameters.
Conclusion: Heavy resistance training for 8 wk improved RE and time to exhaustion at MAS among well-trained, long-distance runners, without concurrent increase in maximal oxygen uptake or body weight. The matched control group exhibited no changes in any of the measured parameters.
Read the full study: https://pubmed.ncbi.nlm.nih.gov/18460997/