João Vilas-boas | Universidade do Porto (original) (raw)
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Papers by João Vilas-boas
Revista portuguesa de ciências do desporto, 2011
Revista Corpoconsciência, Jul 28, 2021
ISBS-Conference …, 2011
The purpose of this study was to perform a preliminary validation of a new electronic instrument ... more The purpose of this study was to perform a preliminary validation of a new electronic instrument for human movement and performance assessment in sports. Measurements of distance, walking speed, step length and frequency were acquired, for a ...
Livro de actas do …, 2011
DOAJ (DOAJ: Directory of Open Access Journals), Feb 1, 2022
Sports Biomechanics, Oct 12, 2022
ISBS - Conference Proceedings Archive, 2012
Motor Control, Oct 1, 2019
Revista portuguesa de ciências do desporto, 2018
International Journal of Sports Medicine, Sep 22, 2010
This study analysed motor control during front crawl swimming starts by elite and trained swimmer... more This study analysed motor control during front crawl swimming starts by elite and trained swimmers, based on comparisons of: 1) kinematic and kinetic parameters of the start and 2) variability of these parameters across 3 trials per swimmer. Given that the start time to the 15-m mark is greatly influenced by the swimming phase, the study also compared the stroking and coordinative parameters from water entry to 25-m in the 2 skill groups. The swimmers performed 3 x 25-m at the 50-m race-pace and used their preferential start technique (grab start). The elite swimmers showed better start organization as reflected by higher impulse values in the direction of intended displacement despite similar block phase durations. They then spent more time in the water entry, gliding and leg kicking phases, with shorter swimming phase duration and 15-m start time than the trained swimmers (p<0.05). The trained swimmers showed significantly lower values for stroke length and velocity (p<0.05) during the swimming phase. Analysis revealed low intra-subject variability (across the 3 trials) but high inter-subject variability, indicating that both elite and trained swimmers had mastered distinct, though different, motor patterns.
International Journal of Environmental Research and Public Health, Nov 26, 2019
International Journal of Sports Medicine, Sep 12, 2011
Studies that aim to characterize oxygen uptake kinetics in efforts above maximal oxygen consumpti... more Studies that aim to characterize oxygen uptake kinetics in efforts above maximal oxygen consumption intensity are scarce. Our aim was to analyze the oxygen kinetics in a maximal 200-m front crawl, all measurements being conducted in swimming pool conditions. 10 high-level male swimmers performed a maximal 200-m bout and oxygen uptake was directly measured through breath-by-breath gas analysis. Mean (±SD) peak oxygen uptake was 68.58 (±5.79) ml.kg(-1).min(-1), evidencing a fast component phase. As expected, peak oxygen uptake presented a direct relationship with mean swimming speed of the first 50-m lap and with the 200-m effort, and was also correlated with the amplitude of the fast component (r=0.75, r=0.72, r=0.73, p&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;0.05, respectively). The observed mean amplitude value was higher than those observed in the literature for other exercise intensity domains. However, the time for its onset, as well as the duration for attaining the steady state, was shorter, as the peak oxygen uptake was not correlated with these 2 components. Moreover, as previously described for swimming at high intensities, the slow component phenomenon was not observed. Aerobic metabolic pathway accounted for 78.6%, confirming the high aerobic contribution in middle distance swimming events.
Journal of Sports Sciences, Feb 4, 2019
ISBS - Conference Proceedings Archive, 2011
The Open Sports Sciences Journal, May 20, 2010
Journal of Science and Medicine in Sport
Sports Biomechanics, 2022
Individual starts for ventral and dorsal swimming events have changed. After the introduction of ... more Individual starts for ventral and dorsal swimming events have changed. After the introduction of back plate and wedge, some studies (mainly on ventral starts) have aimed to clarify their benefits and optimal application. This systematic review is aimed at a critical appraise of the literature on the main findings for back plate and wedge usage. We explored the databases of PubMed, Scopus and Web of Science and conducted a manual search on the reference list of papers. We based our search on the quality scale of the National Health Institutes and found 25 studies that met the eligibility criteria and that scored 7.75 ± 1.18 and 8.0 ± 0.71 on fair-quality studies addressing kick and backstroke starts. Kick start has shown faster start time comparing with grab and track starts by reducing block time and increasing horizontal take-off velocity. Backstroke start using the wedge improved performance through a greater centre of mass vertical position at take-off, horizontal and vertical position at entry and underwater velocity. Swimmers have adopted technical variants of kick and backstroke start by changing block set-up and stance, which should be monitored considering anthropometrics and strength abilities.
Cold provocation tests are largely used in clinical and research settings, but conductive cold pr... more Cold provocation tests are largely used in clinical and research settings, but conductive cold provocation tests have not been applied in the feet. This study analyses skin temperature dynamics after a conductive cold provocation test in a sample of 30 diabetic patients and 30 healthy controls. The test was easy and practical to apply and induced significant temperature changes immediately after and 5 minutes after the test. Tsk dynamics were similar in both groups. The cooling of the plantar surface was not homogenous with large differences in TSk drops between some regions of interest.
Revista portuguesa de ciências do desporto, 2011
Revista Corpoconsciência, Jul 28, 2021
ISBS-Conference …, 2011
The purpose of this study was to perform a preliminary validation of a new electronic instrument ... more The purpose of this study was to perform a preliminary validation of a new electronic instrument for human movement and performance assessment in sports. Measurements of distance, walking speed, step length and frequency were acquired, for a ...
Livro de actas do …, 2011
DOAJ (DOAJ: Directory of Open Access Journals), Feb 1, 2022
Sports Biomechanics, Oct 12, 2022
ISBS - Conference Proceedings Archive, 2012
Motor Control, Oct 1, 2019
Revista portuguesa de ciências do desporto, 2018
International Journal of Sports Medicine, Sep 22, 2010
This study analysed motor control during front crawl swimming starts by elite and trained swimmer... more This study analysed motor control during front crawl swimming starts by elite and trained swimmers, based on comparisons of: 1) kinematic and kinetic parameters of the start and 2) variability of these parameters across 3 trials per swimmer. Given that the start time to the 15-m mark is greatly influenced by the swimming phase, the study also compared the stroking and coordinative parameters from water entry to 25-m in the 2 skill groups. The swimmers performed 3 x 25-m at the 50-m race-pace and used their preferential start technique (grab start). The elite swimmers showed better start organization as reflected by higher impulse values in the direction of intended displacement despite similar block phase durations. They then spent more time in the water entry, gliding and leg kicking phases, with shorter swimming phase duration and 15-m start time than the trained swimmers (p<0.05). The trained swimmers showed significantly lower values for stroke length and velocity (p<0.05) during the swimming phase. Analysis revealed low intra-subject variability (across the 3 trials) but high inter-subject variability, indicating that both elite and trained swimmers had mastered distinct, though different, motor patterns.
International Journal of Environmental Research and Public Health, Nov 26, 2019
International Journal of Sports Medicine, Sep 12, 2011
Studies that aim to characterize oxygen uptake kinetics in efforts above maximal oxygen consumpti... more Studies that aim to characterize oxygen uptake kinetics in efforts above maximal oxygen consumption intensity are scarce. Our aim was to analyze the oxygen kinetics in a maximal 200-m front crawl, all measurements being conducted in swimming pool conditions. 10 high-level male swimmers performed a maximal 200-m bout and oxygen uptake was directly measured through breath-by-breath gas analysis. Mean (±SD) peak oxygen uptake was 68.58 (±5.79) ml.kg(-1).min(-1), evidencing a fast component phase. As expected, peak oxygen uptake presented a direct relationship with mean swimming speed of the first 50-m lap and with the 200-m effort, and was also correlated with the amplitude of the fast component (r=0.75, r=0.72, r=0.73, p&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;0.05, respectively). The observed mean amplitude value was higher than those observed in the literature for other exercise intensity domains. However, the time for its onset, as well as the duration for attaining the steady state, was shorter, as the peak oxygen uptake was not correlated with these 2 components. Moreover, as previously described for swimming at high intensities, the slow component phenomenon was not observed. Aerobic metabolic pathway accounted for 78.6%, confirming the high aerobic contribution in middle distance swimming events.
Journal of Sports Sciences, Feb 4, 2019
ISBS - Conference Proceedings Archive, 2011
The Open Sports Sciences Journal, May 20, 2010
Journal of Science and Medicine in Sport
Sports Biomechanics, 2022
Individual starts for ventral and dorsal swimming events have changed. After the introduction of ... more Individual starts for ventral and dorsal swimming events have changed. After the introduction of back plate and wedge, some studies (mainly on ventral starts) have aimed to clarify their benefits and optimal application. This systematic review is aimed at a critical appraise of the literature on the main findings for back plate and wedge usage. We explored the databases of PubMed, Scopus and Web of Science and conducted a manual search on the reference list of papers. We based our search on the quality scale of the National Health Institutes and found 25 studies that met the eligibility criteria and that scored 7.75 ± 1.18 and 8.0 ± 0.71 on fair-quality studies addressing kick and backstroke starts. Kick start has shown faster start time comparing with grab and track starts by reducing block time and increasing horizontal take-off velocity. Backstroke start using the wedge improved performance through a greater centre of mass vertical position at take-off, horizontal and vertical position at entry and underwater velocity. Swimmers have adopted technical variants of kick and backstroke start by changing block set-up and stance, which should be monitored considering anthropometrics and strength abilities.
Cold provocation tests are largely used in clinical and research settings, but conductive cold pr... more Cold provocation tests are largely used in clinical and research settings, but conductive cold provocation tests have not been applied in the feet. This study analyses skin temperature dynamics after a conductive cold provocation test in a sample of 30 diabetic patients and 30 healthy controls. The test was easy and practical to apply and induced significant temperature changes immediately after and 5 minutes after the test. Tsk dynamics were similar in both groups. The cooling of the plantar surface was not homogenous with large differences in TSk drops between some regions of interest.