West, DJ, Cunningham, DJ, Finn, CV, Scott, PM, Crewther, BT, Cook, CJ, and Kilduff, LP. The metabolic, hormonal, biochemical, and neuromuscular function responses to a backward sled drag training session. J Strength Cond Res 28(1): 265–272, 2014—We examined the metabolic, hormonal, biochemical, and neuromuscular function (NMF) responses to a backward sled drag training session (STS) in strength-trained men (n = 11). After baseline collection of saliva (testosterone and cortisol), whole blood (lactate and creatine kinase [CK]), and countermovement jumps (peak power output), participants completed 5 sets of 2 × 20-m (30 second-recovery between drags and 120 second-recovery between sets) maximal backward sled drags (loaded with 75% body mass). Participants were retested immediately, 15 minutes, 1, 3, and 24 hours after STS. Peak power output decreased after STS (baseline, 4,445 ± 705 vs. 0 minute, 3,464 ± 819 W; p = 0.001) and remained below baseline until recovering at both the 3- and 24-hour time points. No changes in CK levels were seen at any time point after STS. Blood lactate increased immediately after STS (baseline, 1.7 ± 0.5 vs. 0 minute, 12.4 ± 2.6 mmol·L−1; p = 0.001) and remained elevated at 60 minutes (3.8 ± 1.9 mmol·L−1; p = 0.004) before returning to baseline at 3 and 24 hours. Testosterone peaked at 15 minutes post (baseline, 158 ± 45 vs. 15 minutes, 217 ± 49 pg·ml−1; p < 0.001) before decreasing below baseline at the 3-hour time point (119 ± 34 pg·ml−1; p = 0.008), but then increased again above baseline at 24 hours (187 ± 56 pg·ml−1; p = 0.04). Cortisol tended to increase at 15 minutes (baseline, 3.4 ± 1.8 vs. 15 minutes, 5.2 ± 2.7 ng·ml−1; p = 0.07) before declining below baseline at 3 hours (1.64 ± 0.93 ng·ml−1; p = 0.012) and returning to baseline concentrations at 24 hours. In conclusion, sled dragging provides an effective metabolic stimulus, with NMF restored after ≤3 hours of recovery. Characterizing the recovery time course after sled training may aid in athlete training program design.
1Department of Sport and Exercise Science, School of Life Science, Northumbria University, Newcastle upon Tyne, United Kingdom;
2Health and Sport Portfolio, College of Engineering, Swansea University, Swansea, United Kingdom;
3Hamlyn Center, Institute of Global Health Innovation, Imperial College, London, United Kingdom; and
4Sport and Exercise Science, University of Bath, Bath, United Kingdom
Address correspondence to Dr. Liam P. Kilduff, email@example.com.