The original purpose of this investigation was to determine if soccer players who performed an agility training program in a specialized training shoe would have a lower incidence of acute ankle sprains as compared to controls. Two elite male college soccer teams participated in the study. The experimental team performed an agility training program two to three days per week over a three month period wearing the Nike Free Trainer. Data on ankle sprain incidence throughout the season was collected, as well as scores on tests of ankle strength, static balance, dynamic balance, agility and self-reports of ankle function. These scores were compared to those of the control team. Statistical analysis showed a statistically significant improvement in the experimental team members in the anteromedial reach direction of the dynamic balance test (p=0.001). This group also showed positive trends in ankle strength ratio and five of the eight other reach directions of the dynamic balance test. Unfortunately, pre-test, post-test statistical analysis was possible for only half of the experimental team subjects. Post-test data was not generated for the other half of these subjects due to unrelated injury or subject noncompliance. Lack of pre-test data due to subject non-compliance in the control team hindered between group statistical comparisons. This study uncovered promising trends as to the potential for gains in dynamic balance as a result of agility training with Nike Free Trainer. This study also established the reliability of three clinical tests of ankle strength, static balance and dynamic balance. Future well-designed studies are recommended to research this area further to discern the effect of this agility training program on dynamic balance and establish its’ effect on ankle sprain incidence.

The original purpose of this investigation was to determine if soccer players who performed an agility training program in a specialized training shoe would have a lower incidence of acute ankle sprains as compared to controls. Two elite male college soccer teams participated in the study. The experimental team performed an agility training program two to three days per week over a three month period wearing the Nike Free Trainer. Data on ankle sprain incidence throughout the season was collected, as well as scores on tests of ankle strength, static balance, dynamic balance, agility and self-reports of ankle function. These scores were compared to those of the control team. Statistical analysis showed a statistically significant improvement in the experimental team members in the anteromedial reach direction of the dynamic balance test (p=0.001). This group also showed positive trends in ankle strength ratio and five of the eight other reach directions of the dynamic balance test. Unfortunately, pre-test, post-test statistical analysis was possible for only half of the experimental team subjects. Post-test data was not generated for the other half of these subjects due to unrelated injury or subject noncompliance. Lack of pre-test data due to subject non-compliance in the control team hindered between group statistical comparisons. This study uncovered promising trends as to the potential for gains in dynamic balance as a result of agility training with Nike Free Trainer. This study also established the reliability of three clinical tests of ankle strength, static balance and dynamic balance. Future well-designed studies are recommended to research this area further to discern the effect of this agility training program on dynamic balance and establish its’ effect on ankle sprain incidence.

The original purpose of this investigation was to determine if soccer players who performed an agility training program in a specialized training shoe would have a lower incidence of acute ankle sprains as compared to controls. Two elite male college soccer teams participated in the study. The experimental team performed an agility training program two to three days per week over a three month period wearing the Nike Free Trainer. Data on ankle sprain incidence throughout the season was collected, as well as scores on tests of ankle strength, static balance, dynamic balance, agility and self-reports of ankle function. These scores were compared to those of the control team. Statistical analysis showed a statistically significant improvement in the experimental team members in the anteromedial reach direction of the dynamic balance test (p=0.001). This group also showed positive trends in ankle strength ratio and five of the eight other reach directions of the dynamic balance test. Unfortunately, pre-test, post-test statistical analysis was possible for only half of the experimental team subjects. Post-test data was not generated for the other half of these subjects due to unrelated injury or subject noncompliance. Lack of pre-test data due to subject non-compliance in the control team hindered between group statistical comparisons. This study uncovered promising trends as to the potential for gains in dynamic balance as a result of agility training with Nike Free Trainer. This study also established the reliability of three clinical tests of ankle strength, static balance and dynamic balance. Future well-designed studies are recommended to research this area further to discern the effect of this agility training program on dynamic balance and establish its’ effect on ankle sprain incidence. / Education, Faculty of / Kinesiology, School of / Graduate

No description available.

No description available.

A entorse de tornozelo pode ocorrer pela amplitude exagerada de inversão e flexão plantar. Lacuna importante no controle postural é a ação do ajuste postural antecipatório (APA) e compensatório (APC) para estabilizar a articulação do tornozelo. O reflexo de estiramento (M1) e as reações pré-programadas (M2 e M3) foram pouco exploradas em pessoas com instabilidade crônica de tornozelo (CAI). A co-ativação e inibição são fenômenos modulados em nível medular por neurônios excitatórios e inibitórios, mas as informações sobre esses fenômenos atuam na CAI são escassas. A fadiga muscular afeta negativamente as pessoas na condição de CAI. Logo, qual é a relação entre APA e APC no movimento de entorse de tornozelo? A CAI pode alterar as respostas M1, M2 e M3 por lesões osteomioarticulares do tornozelo? A fadiga pode alterar todas estas variáveis em pessoas com CAI? Esta dissertação de mestrado teve por objetivo geral analisar o sinal EMG no movimento simulado da inversão de tornozelo em atletas universitárias de futsal que possuem e que não possuem a CAI. A amostra foi composta por 24 atletas de futsal feminino universitário e foram divididos em dois grupos: controle e instabilidade. A simulação do movimento de entorse do tornozelo foi feita por meio de uma plataforma mecânica que simula o movimento de inversão de tornozelo. Foi utilizado um sistema de aquisição de sinais de 8 canais, onde foram utilizados 4 canais para registro EMG e 3 canais para o registro do sinal do acelerômetro. Para determinar o início e final do movimento da plataforma foi fixado um acelerômetro 3D em uma das bordas da plataforma de inversão. Foram realizar quedas aleatórias na plataforma de inversão antes e depois do protocolo de fadiga. Foram monitorados os músculos tibial anterior, fibular longo e curto e gastrocnêmio lateral. Os períodos analisados foram os APA, APC, reflexo de estiramento muscular e reações pré-programadas. Parece que durante os períodos M1, M2 e M3 há um fator de desproteção no grupo instabilidade, apesar de haver em alguns pares de músculos uma maior coerência, comparado com o grupo controle. Durante o APA os músculos eversores não foram alterados no grupo instabilidade, mas no APC os eversores foram menores comparados com o grupo controle, sugerindo um fator de desproteção. Na correlação cruzada, todos os pares de músculos foram maiores no grupo controle, uma forma de se opor ao movimento de inversão maior que o grupo instabilidade. A co-ativação e inibição recíproca foram alteradas com a fadiga, aumentando após a fadiga, mas a inibição recíproca foi maior somente no grupo controle, podendo mover a articulação do tornozelo de uma forma mais facilitada que o grupo instabilidade. A coerência de pares de músculos foi diferente somente nos grupos, sendo que durante o APC os músculos não sincronizaram de forma satisfatória no grupo instabilidade, somente durante APA e período M / Ankle sprain is an injury associated with sports and exercise and may be used for the exaggerated amplitude of inversion and plantar flexion. An important gap in postural control is the anticipatory (APA) and compensatory (CPA) postural adjustments to stabilize the ankle joint. The stretch reflex (M1) and the pre-programmed reactions (M2 and M3) were poorly explored in people with chronic ankle instability (CAI). Coactivation and recíprocal inhibition are phenomena modulated at the spinal level by excitatory and inhibitory neurons, but the information about these phenomena in CAI is scarce. Negative effects of muscular fatigue affect persons with CAI. Therefore, What is the relationship between APA and CPA in the movement of ankle sprain? Can CAI change the M1, M2 and M3 responses due to osteomyoarticular ankle injuries? Can fatigue change all these variables in people with CAI? This dissertation aimed at analysing the EMG signal in the simulated ankle inversion movement task in female indoor soccer university athletes who have and do not have the CAI. Participants were 24 female indoor soccer college athletes divided in two groups: control and instability. Simulation of ankle sprain was performed with a mechanical platform that simulated the ankle inversion movement. An 8-channel signal acquisition system was used, which 4 channels were used for EMG recording and 3 channels to record accelerometer signal. For determine the beginning and end of the movement of the inversion platform a 3D accelerometer was fixed to one of the edges of the inversion platform. We performed random falls on the inversion platform before and after the fatigue protocol. Muscles monitored were mm. tibialis anterior, fibularis longus, fibularis brevis and gastrocnemius lateralis. Data epochs were APA, CPA, muscle stretching reflex and preprogramed reactions. During M1, M2 and M3 epochs, there was an unprotection factor for instability group, although in some muscle pairs there were more coherence compared to control group. The eversor muscles were not changed in instability group compared with control group during APA epoch, it suggests an unprotect factor. All pair of muscles, the cross correlation were greater in control group to oppose the inversion movement greater in control group than instability group. Coactivation and reciprocal inhibition were changed with fatigue, increasing after fatigue, but reciprocal inhibition was greater only in control group, and could move the ankle joint more easily than for instability group. Coherence of muscle pairs was different only between groups, and during CPA the muscles did not synchronize satisfactorily for instability group, only during APA and M epochs

The purpose of this study was to examine the effects of landing on a combined inverted and plantarflexed surface on the ankle kinematics and electromyographic (EMG) activities of the medial gastrocnemius (MG), peroneal longus (PL) and anterior tibialis muscles (TA). Twelve recreational athletes performed five drop landings from an overhead bar of 30 cm height on to each of these surfaces: a flat surface, a 25° inversion surface (inverted), and a combined surface (combined) of 25° inversion and 25° plantarflexion. The three dimensional kinematic variables and integrated EMG (IEMG) of the three muscles were assessed using one-way repeated measures analysis of variance (ANOVA, p < 0.05) and a 3 × 3 (surface × muscle) ANOVA, respectively. 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 and ankle plantarflexion angle were significantly higher for the combined surface compared to the inverted surface. These findings suggest that compared to inversion, a combination of plantarflexion and inversion provides a more realistic surface for simulating lateral ankle sprains.

The purpose of this study was to examine the effects of landing on a combined inverted and plantarflexed surface on the ankle kinematics and electromyographic (EMG) activities of the medial gastrocnemius (MG), peroneal longus (PL) and anterior tibialis muscles (TA). Twelve recreational athletes performed five drop landings from an overhead bar of 30 cm height on to each of these surfaces: a flat surface, a 25° inversion surface (inverted), and a combined surface (combined) of 25° inversion and 25° plantarflexion. The three dimensional kinematic variables and integrated EMG (IEMG) of the three muscles were assessed using one-way repeated measures analysis of variance (ANOVA, p < 0.05) and a 3 × 3 (surface × muscle) ANOVA, respectively. 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 and ankle plantarflexion angle were significantly higher for the combined surface compared to the inverted surface. These findings suggest that compared to inversion, a combination of plantarflexion and inversion provides a more realistic surface for simulating lateral ankle sprains.

A entorse de tornozelo pode ocorrer pela amplitude exagerada de inversão e flexão plantar. Lacuna importante no controle postural é a ação do ajuste postural antecipatório (APA) e compensatório (APC) para estabilizar a articulação do tornozelo. O reflexo de estiramento (M1) e as reações pré-programadas (M2 e M3) foram pouco exploradas em pessoas com instabilidade crônica de tornozelo (CAI). A co-ativação e inibição são fenômenos modulados em nível medular por neurônios excitatórios e inibitórios, mas as informações sobre esses fenômenos atuam na CAI são escassas. A fadiga muscular afeta negativamente as pessoas na condição de CAI. Logo, qual é a relação entre APA e APC no movimento de entorse de tornozelo? A CAI pode alterar as respostas M1, M2 e M3 por lesões osteomioarticulares do tornozelo? A fadiga pode alterar todas estas variáveis em pessoas com CAI? Esta dissertação de mestrado teve por objetivo geral analisar o sinal EMG no movimento simulado da inversão de tornozelo em atletas universitárias de futsal que possuem e que não possuem a CAI. A amostra foi composta por 24 atletas de futsal feminino universitário e foram divididos em dois grupos: controle e instabilidade. A simulação do movimento de entorse do tornozelo foi feita por meio de uma plataforma mecânica que simula o movimento de inversão de tornozelo. Foi utilizado um sistema de aquisição de sinais de 8 canais, onde foram utilizados 4 canais para registro EMG e 3 canais para o registro do sinal do acelerômetro. Para determinar o início e final do movimento da plataforma foi fixado um acelerômetro 3D em uma das bordas da plataforma de inversão. Foram realizar quedas aleatórias na plataforma de inversão antes e depois do protocolo de fadiga. Foram monitorados os músculos tibial anterior, fibular longo e curto e gastrocnêmio lateral. Os períodos analisados foram os APA, APC, reflexo de estiramento muscular e reações pré-programadas. Parece que durante os períodos M1, M2 e M3 há um fator de desproteção no grupo instabilidade, apesar de haver em alguns pares de músculos uma maior coerência, comparado com o grupo controle. Durante o APA os músculos eversores não foram alterados no grupo instabilidade, mas no APC os eversores foram menores comparados com o grupo controle, sugerindo um fator de desproteção. Na correlação cruzada, todos os pares de músculos foram maiores no grupo controle, uma forma de se opor ao movimento de inversão maior que o grupo instabilidade. A co-ativação e inibição recíproca foram alteradas com a fadiga, aumentando após a fadiga, mas a inibição recíproca foi maior somente no grupo controle, podendo mover a articulação do tornozelo de uma forma mais facilitada que o grupo instabilidade. A coerência de pares de músculos foi diferente somente nos grupos, sendo que durante o APC os músculos não sincronizaram de forma satisfatória no grupo instabilidade, somente durante APA e período M / Ankle sprain is an injury associated with sports and exercise and may be used for the exaggerated amplitude of inversion and plantar flexion. An important gap in postural control is the anticipatory (APA) and compensatory (CPA) postural adjustments to stabilize the ankle joint. The stretch reflex (M1) and the pre-programmed reactions (M2 and M3) were poorly explored in people with chronic ankle instability (CAI). Coactivation and recíprocal inhibition are phenomena modulated at the spinal level by excitatory and inhibitory neurons, but the information about these phenomena in CAI is scarce. Negative effects of muscular fatigue affect persons with CAI. Therefore, What is the relationship between APA and CPA in the movement of ankle sprain? Can CAI change the M1, M2 and M3 responses due to osteomyoarticular ankle injuries? Can fatigue change all these variables in people with CAI? This dissertation aimed at analysing the EMG signal in the simulated ankle inversion movement task in female indoor soccer university athletes who have and do not have the CAI. Participants were 24 female indoor soccer college athletes divided in two groups: control and instability. Simulation of ankle sprain was performed with a mechanical platform that simulated the ankle inversion movement. An 8-channel signal acquisition system was used, which 4 channels were used for EMG recording and 3 channels to record accelerometer signal. For determine the beginning and end of the movement of the inversion platform a 3D accelerometer was fixed to one of the edges of the inversion platform. We performed random falls on the inversion platform before and after the fatigue protocol. Muscles monitored were mm. tibialis anterior, fibularis longus, fibularis brevis and gastrocnemius lateralis. Data epochs were APA, CPA, muscle stretching reflex and preprogramed reactions. During M1, M2 and M3 epochs, there was an unprotection factor for instability group, although in some muscle pairs there were more coherence compared to control group. The eversor muscles were not changed in instability group compared with control group during APA epoch, it suggests an unprotect factor. All pair of muscles, the cross correlation were greater in control group to oppose the inversion movement greater in control group than instability group. Coactivation and reciprocal inhibition were changed with fatigue, increasing after fatigue, but reciprocal inhibition was greater only in control group, and could move the ankle joint more easily than for instability group. Coherence of muscle pairs was different only between groups, and during CPA the muscles did not synchronize satisfactorily for instability group, only during APA and M epochs

No description available.