Percorrer por autor "Fernandes, Ricardo J."
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- Biomechanical and bioenergetical evaluation of swimmers using fully-tethered swimming: A qualitative reviewPublication . Amado, Nuno M.; Morouço, Pedro, G.; Marques, Mário C.; Fernandes, Ricardo J.; Marinho, Daniel A.It is presented a qualitative review of the specialized literature on fully-tethered swimming, with the scopes of summarizing and highlighting published knowledge, identifying its gaps and limitations, and motivate future research. The major research conclusions can be summarized as follows: (i) tethered swimming is a reliable test to evaluate force exerted in water by swimmers; (ii) higher maximum values of force are obtained in breaststroke and butterfly, while average values are higher in front crawl; (iii) tethered forces present moderate to strong relationships with swimming velocity, and associations between forces diminish as swimming distance increases; (iv) 30 s maximal tethered swimming may be used as an adaptation of Wingate test for swimming; (v) differences in stroke mechanics can occur in tethered swimming but there is no evidence to suggest that they affect swimming performance; (vi) Tethered swimming is a valid methodology to evaluate aerobic energy contribution in swimming and recent investigations concluded that it can also provide information on the anaerobic contribution. Based on and stimulated by current knowledge, further research should focus on the following topics: (i) the usefulness of tethered swimming as a valid tool to evaluate other swimming techniques; (ii) differences in force parameters induced by gender or competitive level; (iii) defining accurate variables for estimation of anaerobic power and/or capacity using tethered swimming; (iv) bilateral asymmetries in exerted forces, and corresponding influence of breathing; (v) relative contribution of arms and legs for whole-body propelling forces
- Evaluation of Adolescent Swimmers Through a 30-s Tethered TestPublication . Morouço, Pedro G.; Vilas-Boas, João P.; Fernandes, Ricardo J.Our purpose was to demonstrate that 30-s tethered swimming test can be a useful tool to estimate swimming performance in short distance freestyle events. Thirteen high level adolescent swimmers (7 male and 6 female of16.6 ± 1.0 and 15.8 ± 0.8 years old) performed a 30-s maximum effort in front crawl tethered swimming. Afterward, subjects completed 50-m and 100-m freestyle events at the National Championships. Both maximum and mean force values obtained in the tethered test related directly with 50-m (r =.78 and r =.72, p <.01, respectively) and 100-m freestyle velocities (r =.63 and r =.61, p <.05, respectively). Fatigue index did not present a significant relationship with any of the studied performance variables. However, a proposed parameter-fatigue slope-correlated with 50-m (r=-.75, p <.01), 100-m performances (r=-.57, p <.05) and with r[La-] (r=-.90, p <.01). It is concluded that, for adolescent swimmers, values obtained from 30-s tethered test are well related with swimming performance in sprint events. In addition, fatigue slope seems to be more associated with swimming performance in short distance events than fatigue index.
- Quantification of upper limb kinetic asymmetries in front crawl swimmingPublication . Morouço, Pedro; Marinho, Daniel A.; Fernandes, Ricardo J.; Marques, Mário C.This study aimed at quantifying upper limb kinetic asymmetries in maximal front crawl swimming and to examine if these asymmetries would affect the contribution of force exertion to swimming performance. Eighteen high level male swimmers with unilateral breathing patterns and sprint or middle distance specialists, volunteered as participants. A load-cell was used to quantify the forces exerted in water by completing a 30. s maximal front crawl tethered swimming test and a maximal 50. m free swimming was considered as a performance criterion. Individual force-time curves were obtained to calculate the mean and maximum forces per cycle, for each upper limb. Following, symmetry index was estimated and breathing laterality identified by questionnaire. Lastly, the pattern of asymmetries along the test was estimated for each upper limb using linear regression of peak forces per cycle. Asymmetrical force exertion was observed in the majority of the swimmers (66.7%), with a total correspondence of breathing laterality opposite to the side of the force asymmetry. Forces exerted by the dominant upper limb presented a higher decrease than from the non-dominant. Very strong associations were found between exerted forces and swimming performance, when controlling the isolated effect of symmetry index. Results point that force asymmetries occur in the majority of the swimmers, and that these asymmetries are most evident in the first cycles of a maximum bout. Symmetry index stood up as an influencing factor on the contribution of tethered forces over swimming performance. Thus, to some extent, a certain degree of asymmetry is not critical for short swimming performance.