OBJECTIVE: To evaluate bilateral isokinetic knee extensor and flexor muscle strength relative to hamstring flexibility in female modern dancers. METHODS: 20 trained university-level female modern dance students (mean age 23.8±3.8 yrs) volunteered for the study. Concentric isokinetic peak torque (PT, in Nm), peak torque % of body weight (PT%BW, in Nm/kg), and total work (TW, in J) of the knee extensor and flexor muscles for each leg were measured with a dynamometer at a velocity of 60, 180, and 300°/s. Hamstring flexibility of both limbs was assessed by a goniometer with the subjects in a supine position using the active straight leg raise (SLR) test. Participants were divided into flexible (n=10) and highly flexible (n=10) groups based on their hamstring flexibility. RESULTS: The flexible and highly flexible groups had significant differences (p≤0.05) for the right (flexible, 119.7±4.3°; highly flexible, 137.7±2.6°) and left active SLR tests (flexible, 120.6±5.3°; highly flexible, 138.3±4.5°). No significant differences were found between the flexible and highly flexible dancers for concentric knee extensor and flexor muscle strength in all selected parameters (p≤0.05). There were also no significant correlations between flexibility and bilateral PT, PT%BW, and TW scores (60, 180, and 300°/s) of dancers at the concentric contraction (p≤0.05). CONCLUSION: These findings indicate that hamstring flexibility (for both the flexible and highly flexible groups) is not correlated with knee strength and has no impact on torque and work production during maximal concentric isokinetic knee muscle action in university-level female modern dancers.
11 April 2019 in International Journal of Performance Analysis in Sport
The aim of this study was to determine the use and the variety of body movement difficulty in the routines of individual rhythmic gymnasts aiming to compete in the 2016-Olympic Games, both those who qualified and those who did not. The research data was collected from the routines of 24 rhythmic gymnasts, from a total of 96 videos that were recorded during an Olympic qualification competition for the 34th Rhythmic Gymnastics World Championships of 2015 in Stuttgart/Germany. The gymnasts were divided into G11-15, the top 15 gymnasts, and G216-24, the remaining 9 gymnasts. The number of body movements (jumps/leaps, balances and rotations) and their comparative execution “difficulty” values were examined by quality and quantity. Penché rotation on a flat foot (79.2%), a jeté with a turn jump (66.67%) and balancing with a high back scale leg (57.29%) were the most frequently used body movements. The preferences of G1 gymnasts over G2 gymnasts for different types of static and dynamic difficulties across different movements even where there was not a wide variety. Rhythmic gymnasts at different performance levels generally tend to use the same body movement difficulties for all of their routines and this clearly indicates a lack of body difficulty variation.
This study aims to determine the possible differences anthropometric characteristics and body composition profiles of elite taekwondo players with or without medals in European championships. Twenty-one black-belt elite taekwondo athletes (17.4±1.2 years) from the Turkish national team were divided into two groups, namely, medalists (MEC; n =11) and non-medalists (NmEC; n=10) in European championships. Twenty-eight anthropometric measurements including height, body mass, length, circumferences, breadth, and skinfolds were taken following the standard techniques proposed by the International Society for the Advancement of Kinanthropometry (ISAK). Body composition variables were evaluated by using skinfold thickness measurements. Results demonstrated that anthropometric and body composition, variables did not differ significantly between medalist and non-medalist taekwondo players (p>0.01). Our athletes have a low percentage of body fat and high muscle mass profile. Medalist and non-medalist elite Turkish taekwondo players in the European championships do not differ in terms of anthropometric and body composition components. They have a similar body composition profile suitable for taekwondo players and within acceptable healthy ranges. The present study assists coaches in the formulation of appropriate training programs aiming the development for managing the body composition status of players, which will be associated with high-level performance in taekwondo. Future studies should include body composition and somatotype profile inspection throughout the weight categories.