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Acute effect of whole body vibration on isometric strength, squat jump, and flexibility in well-trained combat athletes

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.

Alternative to traditional stretching methods for flexibility enhancement in well-trained combat athletes: local vibration versus whole-body vibration

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 2nd, 4th, 6th, 8th, 10th and 15th 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.

Comparison of the Effect of Passive and Active Recovery, and Self-Myofascial Release Exercises on Lactate Removal and Total Quality of Recovery

Recovery from exercise-induced fatigue is crucial for subsequent performance. Self-myofascial release (SMR) using a foam roller is an alternative to active recovery (AR). This study aims to compare the effects of passive recovery (PR), AR, and SMR on blood lactate [La - ] removal and total quality of recovery (TQR). Twenty-two well trained male athletes (age: 22.6±2.9 years) underwent three testing sessions conducted 72 hours apart but at the same time of each day in a randomized order. After determining resting [La - ] and heart rate (HR), the subjects completed a Wingate anaerobic test (WAnT), triggering muscular fatigue. HR and [La - ] were measured threeminutes after the WAnT, following which the subjects underwent one of the three different recovery interventions over 15 minutes: PR (lying supine), AR (cycling at 40% of the estimated maximum HR of the respective subject), and SMR (using foam roller on lower extremity muscles). After each recovery intervention, [La - ], HR, and TQR were measured. There was no statistically significant difference in [La - ] and HR values obtained before the WAnT test (p=0.368, p=0.691, respectively) and right after the WAnT test (0.264, p=0.629) Both AR and SMR were more effective than PR for [La - ] removal and obtaining a higher TQR (p 0.05). In contrast, a significantly higher TQR was observed with SMR than AR and PR (p<0.001). Athletes can apply AR or SMR to recover from strenuous exercise. SMR can be an alternative to PR and AR as a recovery tool.

The Effects of Whole Body Vibration Treatments on Lower Body Muscular Activity in Well-Trained Athletes from Different Sports Branches

A limited number of acute whole body vibration (WBV) studies have investigated the effects of WBV treatments which were applied with different vibration frequencies and amplitude combinations on lower extremity muscle activation of well-trained athletes from different sports branches. To compare the effects of WBV on lower extremity muscle activation via Surface Electromyography (sEMG) of well-trained athletes from different sports branches (soccer, basketball and swimming) during static and dynamic squat exercises. sEMG activities of Tibialis Anterior (TA), Gastrocnemius Medialis (GM), Vastus Medialis (VM), Rectus Femoris (RF), Vastus Lateralis (VL) and Biceps Femoris (BF) muscles of 7 male soccer players, 7 male basketball players, and 6 male swimmers were recorded during WBV applied in static squat and dynamic squat positions with different frequencies (30-35-40 Hz) and amplitude (2-4 mm) combinations separated from each other by 5 min passive rest periods. Each combination was applied for 30 sec. The highest muscle activation was determined in TA of the swimmers compared to soccer players during static squat with 4mm-30Hz WBV application (p=0.027). The lowest muscle activation was also determined in VL of the swimmers compared to soccer players during static squat with 2mm-40Hz WBV (p=0.049). During dynamic squat with 4mm-40Hz WBV, the highest muscle activity was determined in RF of the basketball players compared to swimmers (p=0.030). However, dynamic squat with 2mm-40Hz WBV application gave rise to the lowest muscle activation in VL of the basketball players compared to soccer players (p=0.042). Well-trained athletes from different sports branches demonstrated different neuromuscular responses to acute WBV treatments. WBV during dynamic squatting which was applied with 4mm-40 Hz may be more beneficial in enhancing neuromuscular performance acutely for well-trained male athletes since it resulted in higher levels of muscular activation responses according to the present study.

Associations among handgrip strength, dietary pattern, and physical activity level in Physical Education students.

Aim: The purpose of this study was to determine the relationships among handgrip strength (HGS), dietary pattern, and physical activity level in students from a physical education and sport department. Material and Methods: In this study, 124 men and 77 women aged 18–29 y participated. HGS was evaluated in the dominant hand by using an adjustable handgrip dynamometer and expressed in Newton. Dietary pattern was evaluated by using the Dietary Pattern Index (DPI) adapted into the Turkish. Physical activity level was measured by using the short version of the International Physical Activity Questionnaire (IPAQ). Results: The Spearman correlation coefficient showed that HGS positively correlated with IPAQ score (r=0.204, p=0.004), body mass index (r=0.559, p<0.001), and age (r=0.205, p=0.003), but negatively correlated with DPI score (r=−0.179, p=0.01). Conclusion: HGS is a useful, simple, and objective assessment tool for monitoring the physical activity levels and dietary patterns of young subjects.

ACUTE EFFECT OF SELF-MYOFASCIAL RELEASE EXERCISE VOLUME TO VERTICAL JUMP PERFORMANCE AND FLEXIBILITY IN WELL-TRAINED WOMEN VOLLEYBALL PLAYERS

Öz: Amaç: Bu çalışmanın amacı, kendi kendine uygulanan farklı süreli (30 saniye-60 saniye) miyofasiyal gevşetme egzersizlerinin alt ekstremite esneklik ve dikey sıçrama performansı üzerine akut etkilerinin incelenmesidir. Yöntem: Çalışmaya aynı takımda oynayan 18 bayan voleybolcu katılmıştır. Sporculara, 48 saat arayla, randomize crossover çalışma deseni kullanılarak, kontrol, 30 ve 60 saniye süreli foam roller egzersizi olacak şekilde üç farklı uygulama yaptırıldı. Her uygulamanın sonrasında sporculara esneklik (S&R) ve yaylanarak sıçrama testi (CMJ) uygulandı. Bulgular: Araştırmanın sonuçları incelendiğinde, üç uygulama arasında istatistiksel bir farka rastlanmadı (p>0.05). Sonuç: Sonuç olarak, hem 30 hem de 60 saniye süreli foam roller egzersizlerinin benzer etkiye sahip olduğu ve kontrol grubuyla karşılaştırıldığında esneklik ve dikey sıçrama performansı üzerinde olumsuz bir etkiye sahip olmadığı görüldü. Bu sebeple, foam roller ile yapılan self-miyofasiyal gevşetme egzersizleri antrenman ya da yarışmalardan önce alternatif ısınma aracı olarak sporcular tarafından kullanılabilir.