Acute static stretching with different volumes improves hamstring flexibility but not reactive strength index and leg stiffness in well-trained judo athletes

Purpose: The aim of this study was to compare the effects of different volumes of static stretching exercises (SS) on the reactive strength index (RSI), leg stiffness (Kleg), and hamstring flexibility in well-trained judo athletes. Method: In total, 17 international level judo athletes (11 women and 6 men; age, 20.47 ± 1.59 years; experience in judo, 11.35 ± 1.84 years) were recruited for this study. The athletes completed three different SS sessions named low (LV–SS: 3.5 min), moderate (MV–SS: 7 min), and high volumes (HV–SS: 10.5 min), 72 h apart, in a randomized crossover study. Before and after each SS exercise session, hamstring flexibility, RSI and Kleg were evaluated by a sit-and-reach test and a Myotest accelerometric system, respectively. Results: Different volumes of SS exercises improved hamstring flexibility (p .05). Different volumes of SS exercises neither improved nor reduced RSI and Kleg (p > .05). Conclusion: Judo athletes can use LV–SS, MV–SS, or HV-SS for hamstring flexibility enhancement, and SS exercises can be used as a part of a warm-up session prior to judo training or competition

THE EFFECT OF 14 WEEKS STRENGTH AND SERVING EXERCISE WITH YOUNG FEMALE VOLLEYBALL PLAYERS ON TENNIS SERVING

This study aims to determine the effects of strength and serving practices on serving skills performed by volleyball players who practice volleyball regularly. 30 female athletes with an average age of 16.30±0.8 years control group (CG) and 16.44±0.1 years experimental group (EG), who have been participating in volleyball practices on a regular basis for at least five years (90 min/day, three days/week), volunteered for this study. All players were randomly divided into two groups: the EG (n=15) and the CG (n=15). The participants continued attending their regular practices three times a week for 14 weeks, involving technical-tactical training and speed and agility practices required to succeed in volleyball. In addition to these practices, the EG also performed extra serving practices for another hour once a week and participated in strength workout training programs aiming to improve their upper and lower extremities on another day. At the beginning of this study, these players' anthropometric characteristics and ability to get the serve over the net and to serve to a target were noted before and after this 14-week program. When the physical characteristics of these groups were compared, no statistically significant differences were found (p>0.05). However, when the players' ability to get the serve over the net and to serve to a target were compared, statistically significant differences were found between these two groups (p>0.05). Finally, it was concluded that strength and serving practices, in addition to technical practices, which play a crucial role in improving performance and skills in volleyball, improved the serving skills of young female volleyball players; thus, giving extra programs to improve serving skills was found essential.  Article visualizations

Residual effects of static stretching and self-myofascial-release exercises on flexibility and lower body explosive strength in well-trained combat athletes

BACKGROUND: The self-myofascial technique is a new exercise modality that is thought to improve muscular performance and restore soft tissue. However, there are limited empirical data demonstrating the efficacy of this technique on athletic performance. OBJECTIVE: The purpose of this study was to determine the effects of self-myofascial-releasing exercises on the residual characteristics of the sit and reach (S&R) and countermovement jump (CMJ) performance in well-trained combat athletes. METHODS: Sixteen well-trained male combat athletes (age: 23.9 ± 3.6 years, mass: 78.78 ± 10.41 kg, combat experience: 12.87 ± 5.23 years) performed three exercise sessions called "aerobic running (AR)", "aerobic running combined with static stretching (AR + SS)", and "aerobic running combined with self-myofascial release (AR + SMR)" at 48 hour intervals in a randomized crossover design. After each session, the subjects performed the S&R and CMJ tests successively with 30-s of rest between the tests at the 15th second and at the 2nd, 4th, 6th, 8th, 10th, 15th, and 30th minute during the recovery period. RESULTS: ANOVA and the post-hoc LSD (Least Significant Difference) test revealed that the AR + SMR treatment increased the flexibility greater than AR + SS (p = 0.029) at the 45th second. Additionally, the AR + SMR treatment resulted in less of a decrease in CMJ height compared to AR + SS at the 10th minute (p = 0.025). A larger decrease in the CMJ height was found after AR + SS compared to the AR and AR + SMR treatments at the 10th and 15th minute, respectively (p = 0.025 and p = 0.038). These results revealed that SMR had no advantage over AR and SS in terms of enhancing flexibility. A statistically insignificant inhibitory effect of SMR was detected on the CMJ performance. SS appeared to have an inhibitory effect on the CMJ performance for approximately 15 minutes. CONCLUSION: SMR may have a detrimental effect on CMJ performance. Trainers or athletes should consider using the SMR technique before training or competition to prevent possible power decrement. © 2017-IOS Press and the authors. All rights reserved