Leg Power in Elite Male Fencers: A Comparative Study among the Three Competitive Disciplines

Transcription

1 Leg Power in Elite Male Fencers: A Comparative Study among the Three Competitive Disciplines Gustavo D. Aquilino, Aldo F. Longo, Néstor A. Lentini. Exercise Physiology Laboratory, National Sport High Performance Center (CeNARD), Buenos Aires, Argentina. ABSTRACT The motor response of a fencer is required to be fast and explosive. Leg power plays a key role in the competitive fencing disciplines. PURPOSE: To compare leg power performance of elite male fencers by competitive discipline. METHODS: Data of 18 fencers who took part in the Argentine national team were considered in the study (Age = ± 5.26 yr, Weight = ± 8.16 kg, Height = 1.81 ± 0.06 m; mean ± SD). Three groups of 6 subjects each were defined according to the competitive disciplines of the sport: Épée, Foil and Sabre. Leg Power was indirectly measured through the assessment of height jumped following three well-known protocols: Abalakov Jump, Counter Movement Jump and Squat Jump. A contact platform was used to assess height jumped. Lewis formula was employed for calculation of Average Power (AP). Based on data gathered over several years, the best performance of each subject was selected for the analyses. ANCOVAs were conducted on AP for Abalakov, Counter Movement and Squat Jumps; Weapon was the independent factor in the analyses and Weight was introduced as a covariable. Linear associations among the three vertical jumps were evaluated on the whole sample by means of Pearson correlation tests; height jumped was used for these analyses. RESULTS: Sample means of height jumped in cm for Épée, Foil and Sabre were, respectively, 51.77, and in Abalakov Jump; 44.83, and in Counter Movement Jump; and 38.97, and in Squat Jump. ANCOVAs on AP were not statistically significant (p>0.05) for Weapon for any of the tests: Abalakov Jump (1159.7, and W; F = 0.14), Counter Movement Jump (1080.6, and W; F = 0.41) and Squat Jump (1011.2, and W; F = 0.24). As predictable, there were found high correlations among vertical jumps (ra,c = 0.92, ra,s = 0.83, rc,s = 0.91; p<0.05). CONCLUSIONS: The results obtained showed negligible differences in AP among the three disciplines of the sport. It would be desirable to obtain further statistical evidence from a larger sample size. Key Words: Fencing; Leg Power; Vertical Jump.

2 INTRODUCTION Fencing is a combat sport. From a metabolic point of view, it requires a high level of anaerobic power for performance success. The motor response of a fencer is required to be fast and explosive. The explosive strength of legs is particularly relevant to achieve the highest competition levels, so leg power plays a key role in the competitive fencing disciplines. Previous investigation revealed that fencing performance is correlated to leg power (Iglesias Reig and Cano Alonso, 1990). The explosive strength of legs evaluated by means of vertical jump is highly related to the percentage of fast-twitch muscle fibers, and exposes the maximum power of the leg extensor muscles (Bosco, 2000). In the fencing competitions, the winner of the bout is the first of the two fencers to reach 5 heats in the pool round, and 15 heats in the instance of direct elimination. In Épée and Foil, there is a time limit of 3 minutes in the pool round and three 3-minute periods separated by 1-minute breaks in direct elimination. In these disciplines, if the bout ends before either fencer has reached 5 (or 15) hits, then the fencer with the most hits is declared the winner. In the modality of Sabre, there is a 1-minute break in the instance of direct elimination when one fencer s score reaches 8. Sabre often involves faster footwork and quicker bouts than Épée and Foil. Given these differences, we wondered if they could be reflected in leg power. Specifically, this study aimed to compare leg power performance of elite male fencers by competitive discipline.

3 METHODS Subjects Data of 18 fencers who took part in the Argentine national team were considered in the study. The participants competed in Olympic Games, Panamerican Games or South American Games. Three groups of 6 subjects each were defined according to the competitive disciplines of the sport: Épée, Foil and Sabre. Descriptive statistics of the basic anthropometric measures of the fencers are shown in Table 1. Table 1. Anthropometric characteristics of the fencers: Descriptive measures. Mean SD Minimum Maximum Age (yr) Weight (kg) Height (m) Procedures Leg power was indirectly measured through the assessment of height jumped following three well-known protocols: Abalakov Jump, Counter Movement Jump and Squat Jump. A contact platform was used to assess height jumped (Axon Jump, Modelo S; size: cm; weight: 7.3 kg, temporal resolution: 1 ms). Average Power (AP) was calculated according to Lewis formula (Fox and Mathews, 1974): [ ] AP = Body mass Height jumped = Watts, (1) where Body mass is in kg and Height jumped is in m. In the jump protocols, the height jumped was assessed three times, and the highest jump was recorded as the subject's maximum height jumped.

4 Statistical Analysis Based on data gathered over several years, the best performance of each subject was selected for the analyses. ANCOVAs were conducted on AP for Abalakov, Counter Movement and Squat Jumps; Weapon was the independent factor in the analyses and Weight was introduced as a covariable. Linear associations among the three vertical jumps were evaluated on the whole sample by means of Pearson correlation tests; height jumped was used for these analyses. Statistical significance was set at the 0.05 probability level. All analyses were performed using R software version RESULTS A statistical summary of the jump heights attained in the three tests is firstly presented in Table 2. Sample means of height jumped in cm for Épée, Foil and Sabre were, respectively, 51.77, and in Abalakov Jump; 44.83, and in Counter Movement Jump; and 38.97, and in Squat Jump. Figure 1 resumes the results categorized by sport discipline corresponding to each vertical jump. ANCOVAs on AP were not statistically significant (p>0.05) for Weapon for any of the tests. Table 3 shows the mean responses and 95% confidence intervals for AP in the three vertical jumps. As predictable, there were found high correlations among the jumps (ra,c = 0.92, ra,s = 0.83, rc,s = 0.91; p<0.05); the corresponding scatter diagrams are presented in Figure 2. Table 2. Statistical summary of the vertical jumps. Vertical Jump Mean Median SD Minimum Perc 25 Perc 75 Maximum Abalakov Counter Movement Squat All values expressed in cm.

5 Table 3. Vertical jumps: Estimates and 95% confidence intervals for AP by Weapon and F-tests. Abalakov Jump Weapon Estimate Lower 95% CI Upper F-value p-value Épée > 0.05 Foil Sabre Counter Movement Jump Weapon Estimate Lower 95% CI Upper F-value p-value Épée > 0.05 Foil Sabre Squat Jump Weapon Estimate Lower 95% CI Upper F-value p-value Épée > 0.05 Foil Sabre All values of AP expressed in Watts. Prediction equations for AP (in Watts) derived from the analyses are the following: A P Weight Foil Sabre, (2) Abalakov = A P Weight Foil Sabre, (3) CM = A P = Weight Foil Sabre, (4) Squat where Weight is in kg, and Foil and Sabre are coded 1 if yes and 0 if no. The R squared values of the statistical models were, respectively, 0.68, 0.78 and 0.76.

6 Figure 1. Abalakov, Counter Movement and Squat Jumps: Plots of means and standard errors by Weapon for height jumped.

7 Figure 2 Scatter diagrams between vertical jumps.

8 Squat Jump.

9 SUMMARY AND CONCLUSION A high level of anaerobic power is a prerequisite for fencers, particularly in elite competition. Previous research showed an association between fencing performance and leg power. Several vertical jump protocols are widely used to indirectly evaluate leg power, such as the Abalakov, Counter Movement and Squat jumps. In the discipline of Sabre, the bouts tend to be shorter and to involve faster movements than in the rest of the fencing disciplines. However, these differences seemed not to be clearly reflected in leg power. The results obtained from the analyses for the vertical jump tests used showed negligible differences in AP among the three disciplines of the sport, being these differences not statistically significant. The highest sample estimates were found in Sabre and the lowest in Épée. Nonetheless, it would be desirable to obtain further statistical evidence from a larger sample size. High positive linear associations were found between the vertical jump tests. Maybe just one of these evaluations would be enough if the goal is only to obtain a measure for comparison purposes. Complementary, prediction equations for AP of elite male fencers are provided for three well-known vertical jump protocols, as well as reference data of maximum height jumped, which are quite similar to the international ones. ACKNOWLEDGMENT The authors wish to thank Víctor Sergio Groupierre and Sergio Turiace for their technical assistance.

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