– Alvonti and colleagues (2014) investigated the effects of different lower body static stretch durations (10, 15, 20, 30, 40, 60 seconds) on speed and agility performance in 34 trained athletes. Each athlete performed a sprint (20 m) and agility test (T-Test) following each stretching procedure on different days in a randomized order. The results showed that the 15-20 seconds of static stretching improved speed and agility, while the longer duration stretches had no effect. When performance level was controlled for, it was revealed that only the athletes of low-moderate speed/agility performance were impacted by the stretching, as the higher level athletes did not show differences in performance under any of the stretching interventions.
– Ataee et al. (2014) studied the effects of strength training with the addition of chains vs. conventional strength training over a 4 week training program. Twenty-four trained male athletes (20 years old) were randomly split into an accommodation group and a constant load group. The participants lifted 3 times per week performing squats and bench presses with 85% of their 1RM for 3 sets of 5. Pre and post testing of strength (1RM) and power (med ball throw and vertical jump) revealed no significant differences in improvements among all variables except maximal squat strength. The accommodation group (using chains) improved 1RM squat strength significantly more than the constant load group.
– Brumitt et al (2014) surveyed 193 Division III athletes on their off-season training habits at the start of the pre-season. The athletes responded to questions regarding what exercises they performed (weight lifting, running ,plyometrics, scrimmage, etc.) as well as how often they performed them. Single leg hop and standing long jump values were then collected. Results showed that the athletes who spent more time training performed better on the performance tests.
– Rumpf et al. (2014) investigated the effects of resisted sprint training (sled towing) on 32 youth athletes. Of the athletes, 18 were determined as pre-peak height velocity, while that remainder were at mid or post-peak height velocity. Over 6 weeks, the athletes performed 12–14 workouts of 8-10 sprints over 15-20 meters. Compared to pre-testing of 30m sprint speed, only the mid/post-peak height velocity group showed significant improvements in sprint performance. Therefore, it is likely unnecessary to have young athletes who have yet to reach peak height velocity perform resisted sprints.
References:
Avloniti, A., Chatzinikolaou, A., Fatouros, I. G., Avloniti, C., Protopapa, M., Draganidis, D., … & Kambas, A. (2014). The Acute Effects of Static Stretching on Speed and Agility Performance Depend on Stretch Duration and Conditioning Level. Journal of Strength and Conditioning Research, Ahead of Print.
Ataee, J., Koozehchian, M. S., Kreider, R. B., & Zuo, L. (2014). Effectiveness of accommodation and constant resistance training on maximal strength and power in trained athletes. PeerJ, 2, e441.
Brumitt, J., Heiderscheit, B. C., Manske, R. C., Niemuth, P. E., & Rauh, M. J. (2014). Off‐season training habits and preseason functional test measures of division iii collegiate athletes: a descriptive report. International journal of sports physical therapy, 9(4), 447.
Rumpf et al. The effect of resisted sprint training on maximum sprint kinetics and kinematics in youth, European Journal of Sport Science, Ahead of print.