F32F FREE COMMUNICATION/SLIDE TRAINING
The major purpose of the present study was to determine whether maximal strength squat training using high loads, few repetitions and maximal mobilization of force might improve running economy, and thus an aerobic endurance performance, as has been shown in female upper body work in previous research. 24 trained subjects from three soccer teams with a mean VO2max of 4.36 L, 59.8 mL · kg−1 · min−1 or 174.5 mL · kg−0.75 · min−1 participated in the study. The training group (TG) performed maximal strength training, 5 repetitions in 4 series of higher loads than 85% of 1 RM with emphasis on maximal mobilization of force in the concentric action, three times per week for 8 weeks. The control group (CG) trained soccer technical training during the same amount of time. IRM increased with 33.7% from 161.3 kg to 215.6 kg in half squats for the TG with no change in bodyweight, whereas no change was reported for the control group. Rate of force development at a maximal voluntary contraction improved by 52.3% and peak force improved by 9.6% in TG, while no change was observed in the CG. Running economy at anaerobic threshold improved by 4.7% from 0.788 to 0.751 mL · kg−0.75 · m−1 while no change was observed in the CG. No change was observed in the parameters VO2max and anaerobic threshold for either group. These data suggest that maximal strength training with emphasis on mobilization of force in the concentric action improves 1RM and rate of force development mainly from neural adaptations altering recruitment patterns and result in improved running economy.