Purpose: The aims of this study were to:(1) provide a comprehensive physiological profile of simulated basketball activity and(2) identify temporal changes in player responses in controlled settings.Methods: State-lev...Purpose: The aims of this study were to:(1) provide a comprehensive physiological profile of simulated basketball activity and(2) identify temporal changes in player responses in controlled settings.Methods: State-level male basketball players(n = 10) completed 4 × 10 min simulated quarters of basketball activity using a reliable and valid courtbased test. A range of physiological(ratings of perceived exertion, blood lactate concentration([BLa~—]), blood glucose concentration([BGlu]), heart rate(HR), and hydration) and physical(performance and fatigue indicators for sprint, circuit, and jump activity) measures were collected across testing.Results: Significantly reduced [BLa~—](6.19 ± 2.30 vs. 4.57 ± 2.33 mmol/L; p = 0.016) and [BGlu](6.91 ± 1.57 vs. 5.25 ± 0.81 mmol/L;p = 0.009) were evident in the second half. A mean HR of 180.1 ± 5.7 beats/min(90.8% ± 4.0% HR max) was observed, with a significant increase in vigorous activity(77%—95% HR max)(11.31 ± 6.91 vs. 13.50 ± 6.75 min; p = 0.024) and moderate decrease in near-maximal activity(>95% HR_(max))(7.24 ± 7.45 vs. 5.01 ± 7.20 min) in the second half. Small increases in performance times accompanied by a significantly lower circuit decrement(11.67% ± 5.55% vs. 7.30% ± 2.16%; p = 0.032) were apparent in the second half.Conclusion: These data indicate basketball activity imposes higher physiological demands than previously thought and temporal changes in responses might be due to adapted pacing strategies as well as fatigue-mediated mechanisms.展开更多
Purpose： The purpose of this study was to examine the effects of landing kinematics and electromyographic （EMG） activities of medial gastrocnemius on a combined inversion and plantarflexion surface on the ankle （M...Purpose： The purpose of this study was to examine the effects of landing kinematics and electromyographic （EMG） activities of medial gastrocnemius on a combined inversion and plantarflexion surface on the ankle （MG）, peroneus longus （PL）, and tibialis anterior （TA） muscles. Methods： Twelve recreational athletes performed five drop landings from an overhead bar of 30 cm height on to three surfaces： a flat surface, a 25° inversion surface, and a combined surface of 25° inversion and 25° plantarflexion. The kinematic variables and integrated EMG （IEMG） of the three muscles were assessed using a one-way repeated measures ANOVA and a 3 × 3 （surface × muscle） ANOVA, respectively （p 〈 0.05）. Results： The IEMG results showed a significant muscle by surface interaction. The flat surface induced higher TA activity than the two tilted surfaces. The inverted surface produced significantly higher inversion peak angle and velocity than the flat surface, but similar PL activity across the surfaces. The MG IEMG, ankle plantarflexion angle, and inversion range of motion were significantly higher for the combined surface compared to the inverted surface. Conclusion： These findings suggest that compared to the inversion surface, the combined plantarflexion and inversion surface seems to provide a more unstable surface condition for lateral ankle sprains during landing.展开更多
基金support of the players and coaches in the Rockhampton representative U18 team
文摘Purpose: The aims of this study were to:(1) provide a comprehensive physiological profile of simulated basketball activity and(2) identify temporal changes in player responses in controlled settings.Methods: State-level male basketball players(n = 10) completed 4 × 10 min simulated quarters of basketball activity using a reliable and valid courtbased test. A range of physiological(ratings of perceived exertion, blood lactate concentration([BLa~—]), blood glucose concentration([BGlu]), heart rate(HR), and hydration) and physical(performance and fatigue indicators for sprint, circuit, and jump activity) measures were collected across testing.Results: Significantly reduced [BLa~—](6.19 ± 2.30 vs. 4.57 ± 2.33 mmol/L; p = 0.016) and [BGlu](6.91 ± 1.57 vs. 5.25 ± 0.81 mmol/L;p = 0.009) were evident in the second half. A mean HR of 180.1 ± 5.7 beats/min(90.8% ± 4.0% HR max) was observed, with a significant increase in vigorous activity(77%—95% HR max)(11.31 ± 6.91 vs. 13.50 ± 6.75 min; p = 0.024) and moderate decrease in near-maximal activity(>95% HR_(max))(7.24 ± 7.45 vs. 5.01 ± 7.20 min) in the second half. Small increases in performance times accompanied by a significantly lower circuit decrement(11.67% ± 5.55% vs. 7.30% ± 2.16%; p = 0.032) were apparent in the second half.Conclusion: These data indicate basketball activity imposes higher physiological demands than previously thought and temporal changes in responses might be due to adapted pacing strategies as well as fatigue-mediated mechanisms.
文摘Purpose： The purpose of this study was to examine the effects of landing kinematics and electromyographic （EMG） activities of medial gastrocnemius on a combined inversion and plantarflexion surface on the ankle （MG）, peroneus longus （PL）, and tibialis anterior （TA） muscles. Methods： Twelve recreational athletes performed five drop landings from an overhead bar of 30 cm height on to three surfaces： a flat surface, a 25° inversion surface, and a combined surface of 25° inversion and 25° plantarflexion. The kinematic variables and integrated EMG （IEMG） of the three muscles were assessed using a one-way repeated measures ANOVA and a 3 × 3 （surface × muscle） ANOVA, respectively （p 〈 0.05）. Results： The IEMG results showed a significant muscle by surface interaction. The flat surface induced higher TA activity than the two tilted surfaces. The inverted surface produced significantly higher inversion peak angle and velocity than the flat surface, but similar PL activity across the surfaces. The MG IEMG, ankle plantarflexion angle, and inversion range of motion were significantly higher for the combined surface compared to the inverted surface. Conclusion： These findings suggest that compared to the inversion surface, the combined plantarflexion and inversion surface seems to provide a more unstable surface condition for lateral ankle sprains during landing.
