Maximal leg-strength training improves cycling economy in previously untrained men

Purpose: This study examined cycling economy before and after 8 wk of maximal leg-strength training. Methods: Seven previously untrained males (25 +/- 2 yr) performed leg-strength training 3 d center dot wk(-1) for 8 wk using four sets of five repetitions at 85% of one repetition maximum (1RM). Body mass, lean-leg muscle mass (LLM), percentage of body fat, and leg strength (1RM) were measured at 0, 4, and 8 wk of training. Cycling economy was calculated as the Delta(V) over dot O-2/Delta WR (change in the O-2 cost of exercise divided by the change in the power between two different power outputs). Results: There were significant increases in LLM and 1RM from 0 to 4 wk of training (LLM: 25.8 +/- 0.7 to 27.2 +/- 0.8 kg; 1RM: 138 +/- 9 to 215 +/- 9 kg). From 4 to 8 wk of training, 1RM continued to increase significantly (215 +/- 9 to 266 +/- 8 kg) with no further change observed in LLM. Peak power during incremental cycling increased significantly (305 +/- 14 to 315 +/- 16 W), whereas the power output achieved at the gas-exchange threshold (GET) remained unchanged. Peak O-2 uptake and the O-2 uptake achieved at the GET also remained unchanged following training. Cycling economy improved significantly when the power output was increased from below the GET to above the GET but not for power outputs below the GET. Conclusion: Maximal leg-strength training improves cycling economy in previously untrained subjects. Increases in leg strength during the final 4 wk of training with unchanged LLM suggest that neural adaptations were present.