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 15^th second and at the 2^nd, 4^th, 6^th, 8^th, 10^th, 15^th, and 30^th 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 45^th second. Additionally, the AR + SMR treatment resulted in less of a decrease in CMJ height compared to AR + SS at the 10^th 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 10^th and 15^th 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.

The purpose of this study was to investigate the effect of whole body vibration (WBV) training on maximal strength, squat jump, and flexibility of well-trained combat athletes. Twelve female and 8 male combat athletes (age: 22.8 ± 3.1 years, mass: 65.4 ± 10.7 kg, height: 168.8 ± 8.8 cm, training experience: 11.6 ± 4.7 years, training volume: 9.3 ± 2.8 hours/week) participated in this study. The study consisted of three sessions separated by 48 hours. The first session was conducted for familiarization. In the subsequent two sessions, participants performed WBV or sham intervention in a randomized, balanced order. During WBV intervention, four isometric exercises were performed (26 Hz, 4 mm). During the sham intervention, participants performed the same WBV intervention without vibration treatment (0 Hz, 0 mm). Hand grip, squat jump, trunk flexion, and isometric leg strength tests were performed after each intervention. The results of a two-factor (pre-post[2] × intervention[2]) repeated measures ANOVA revealed a significant interaction (p = 0.018) of pre-post × intervention only for the hand grip test, indicating a significant performance increase of moderate effect (net increase of 2.48%, d = 0.61) after WBV intervention. Squat jump, trunk flexion, and isometric leg strength performances were not affected by WBV. In conclusion, the WBV protocol used in this study potentiated hand grip performance, but did not enhance squat jump, trunk flexion, or isometric leg strength in well-trained combat athletes.

This study aimed to compare the effect of local vibration (LV) and whole body vibration (WBV) on lower body flexibility and to assess whether vibration treatments were more effective than traditionally used static and dynamic stretching methods. Twenty-four well-trained male combat athletes (age: 22.7 ± 3.3 years) performed four exercise protocols - LV (30 Hz, 4 mm), WBV (30 Hz, 4 mm), static stretching (SS), and dynamic stretching (DS) - in four sessions of equal duration 48 hours apart in a randomized, balanced order. During a 15-minute recovery after each protocol, subjects performed the stand and reach test (S&R) at the 15th second and the 2(nd), 4(th), 6(th), 8(th), 10(th) and 15(th) minute. There was a similar change pattern in S&R scores across the 15-minute recovery after each protocol (p = 0.572), remaining significantly elevated throughout the recovery. A significant main protocol effect was found for absolute change in S&R scores relative to baseline (p = 0.015). These changes were statistically greater in LV than WBV and DS. Changes in SS were not significantly different from LV, but were consistently lower than LV with almost moderate effect sizes. After LV, a greater percentage of subjects increased flexibility above the minimum detectable change compared to other protocols. Subjects with high flexibility (n = 12) benefited more from LV compared with other methods (effect size ≥ 0.862). In conclusion, LV was an effective alternative exercise modality to acutely increase lower extremity flexibility for well-trained athletes compared with WBV and traditional stretching exercises.

Plyometric exercise is a major tool for improving explosive actions. This study aimed to compare the efficacy of a vertical and horizontal plyometric training program on stretch-shortening performance variables in adolescent soccer players. Thirty-two male soccer players (aged 12.09 ± 0.89 years, with soccer experience 5.37 ± 1.58 years) were divided into horizontal plyometric, vertical plyometric, or control groups. The horizontal and vertical plyometric groups participated in a 6-week training program that was performed twice per week, with a 48-h interval, in conjunction with regular soccer training. The control group participated only in regular soccer training. Vertical jump height, reactive strength index, leg stiffness, ground contact time, standing long jump distance, agility, and 10 and 20 m sprint performances were tested as stretch-shortening performance variables of the participants. Stretch-shortening performance variables were assessed before and after completion of the training program. The results showed that either horizontal or vertical plyometric training had no effect on VJH, RSI, GCT, or Kleg performance (F = 2.14, 1.32, 0.66, 1.03; p > 0.05). Furthermore, there was no effect on SLJ, 10 m sprint, 20 m sprint, or agility performance (F = 2.06, 0.14, 0.06, 0.27; p > 0.05). A 6-week horizontal or vertical plyometric intervention was found to be insufficient to elicit stretch-shortening performance enhancement in adolescent male soccer players. Although there was no performance change in any group, it was observed that the players enjoyed plyometric training. Therefore, coaches could safely use plyometric exercises to design enjoyable training programs.

[Purpose] The present study aimed to investigate the lower limbs injury risk factors that are based on conventional Hamstring to Quadriceps ratio and limb asymmetry index in varsity American football players. [Participants and Methods] Twenty-six varsity American football players aged 19–27 years and with 2.31 ± 1.29 years of American football experience from Dogu Akdeniz University volunteered to undergo measurements of average peak torque for isokinetic flexion and extension of dominant limb and non-dominant limb at 60°·s−1 and 300°·s−1. Hamstring to Quadriceps ratio and limb asymmetry index were also calculated for Hamstring and Quadriceps muscles. [Results] Statistical analysis revealed that dominant Quadriceps is stronger than non-dominant Quadriceps at 60°·s−1 speed. No statistical difference was found between dominant and non-dominant Hamstring peak torque at 60°·s−1 . Hamstring to Quadriceps ratio determined as normal both for 60°·s−1 and 300°·s−1according to the currently reported cut off value (H:Q ratio >60). Hamstring and Quadriceps limb asymmetry index also determined as normal (cut off value for LSI 10%) at 60°·s−1. However, for both Hamstring and Quadriceps, side- to- side strength asymmetry at 300°·s−1 was observed. [Conclusion] To prevent possible lower limb injury and to increase performance, varsity American football players who are actively training and competing might consider taking strength asymmetry into account to tailor their strength training program accordingly.