Mario Cezar de Souza Costa Conceição

Acute effects of static stretching on muscle strength

Acute effects of static stretching on muscle strength Study aim: To assess the effects of static passive maximal stretching on muscle performance in order to clarify the existing controversies. Material and methods: Two randomly selected groups of the Brazilian Air Force personnel were studied: experimental (n = 15), subjected to 3 bouts of static passive stretching exercises of wrist flexors and extensors (beyond a mild discomfort). Every bout lasted 10 s and was followed by a 30-s rest. The control group (n = 15) performed no exercises. Muscle strength was measured with a handgrip dynamometer before and 20 min after the test. Results: Subjects from the experimental group had the pre-exercise handgrip strength significantly higher than postexercise (by about 7%; p<0.01). No significant decrease was noted in the control group. Conclusions: Static passive stretching induces decreases in muscle strength.

Flexibility: components, proprioceptive mechanisms and methods

Flexibility: components, proprioceptive mechanisms and methods A literature review on physical flexibility was presented and discussed. This included definitions and components that influence the performance of movements requiring large joint motion ranges and muscle elasticity. Flexibility was discussed with reference to specific age groups, e.g. children and the elderly. Proprioceptive mechanisms and components directly related to flexibility were overviewed, as well as suitable approaches towards flexibilisation, i.e. maintaining and/or enhancing flexibility.

Efeitos crônicos do flexionamento estático sobre parâmetros neuromusculares em adultos jovens

INTRODUCTION: Training includes, among other physical qualities, flexibility and strength. Thus, knowing the mutual inter-relationships between these physical qualities would increase the effectiveness of training. OBJECTIVE: The purpose of this study was to verify changes in neuromuscular parameters in a static flexibilizing program, after 12 weeks of intervention. METHODS: 70 cadets, mean age of 17.03 ± 1.14 years, participated in the present survey, were randomly selected and equally divided into two groups: experimental group (EG, n = 35) and control group (CG, n = 35). Strength levels were assessed by 1RM static contraction in horizontal shoulder flexion and extension (HSF/ HSE) and lumbar spine extension (LSE). Flexibility was assessed by the goniometry LABIFIE protocol in shoulder horizontal flexion and extension (SHF /SHE) and lumbar spine flexion (LSF). The urinary hydroxyproline concentration collected by the Nordin method was performed through HPROLI 2h protocol. RESULTS: ANOVA for repeated measures evidenced significant increase for SHF (Δ% = 3.9%, p = 0.001), SHE (Δ% = 21.1%, p = 0.001), LSF (Δ% = 73.8%, p = 0.001), SHF (Δ% = 20.4%, p = 0.001) and FELS (Δ% = 4.0%, p = 0.008) from pre to post-test. The hydroxyproline levels did not change significantly. Concerning intergroup comparisons, significant differences were found for SHF (p = 0.016), SHE (p = 0.005), LSF (p = 0.004), SHF (p = 0.001) and FELS (p = 0.007). The power of the experiment observed was of 86% for an estimated beta of 0.14. CONCLUSION: The static flexibilizing was able to improve both flexibility and strength.

EXERCÍCIO DE ALTA INTENSIDADE E FLEXIBILIDADE DE MEMBROS INFERIORES: ESTUDO DE DOSE-EFEITO

Introduction: Sports scientists have been studying the phenomenon involving different types of exercises and their influence on other activities. Stretching exercises have a negative influence on muscular strength and power output, as do high intensity or long duration cardiovascular training. Nevertheless, several studies have found the opposite to be true Nevertheless, few investigations have studied the opposite. Objective: To determine whether high intensity power exercise influences muscular flexibility in an acute manner. Methods: A sample of forty-three male and female young adults aged between 18 and 28 years, with a mean age of 22.88 + 3.04 years, who have practiced physical activity for at least six months. To determine flexibility, the sit-and-reach test was used. For the high intensity training, a 45o leg press was used. A 10-rep movement was performed at 85% of 1 RM, in both pre- and post-tests. Statistic analysis was conducted using the ANOVA and Scheffers post-hoc tests, with a level of significance for differences of < 0.05. Results: Comparison of the pre- and post-tests proved to be statistically significant from the baseline from the fourth to the seventh repetitions. Conclusion: Strength exercises at 85% of 1RM seem to significantly increase range of motion in an acute manner, and the growth of this range of motion has a dose-effect response.Introducao: Os cientistas do esporte veem estudando o fenomeno que envolve diferentes tipos de exercicios e sua influencia sobre outras atividades. Os exercicios de alongamento tem influencia negativa sobre a forca e potencia muscular, da mesma forma que o treinamento cardiovascular de longa duracao ou alta intensidade. No entanto, poucas investigacoes tem estudado o oposto. Objetivo: Identificar se o exercicio de alta intensidade tem influencia sobre a flexibilidade muscular de forma aguda. Metodos: Amostra de quarenta e tres jovens adultos do sexo masculino e do sexo feminino entre 18 e 28 anos de idade, com media de idade de 22,88 + 3,04 anos, praticantes de atividade fisica por pelo menos seis meses. Para verificar a flexibilidade, foi utilizado o teste de sentar e alcancar. Para o treinamento de alta intensidade, foi selecionada a pressao de pernas (leg press) em 45o. Foram realizadas 10 repeticoes a 85% de 1 RM, tanto no pre quanto no pos-teste. A analise estatistica foi realizada por ANOVA e testes post hoc de Scheffer, com nivel de significância para diferencas ≤ 0,05. Resultados: A comparacao entre pre e pos-teste mostrou-se estatisticamente significante desde a linha de base, da quarta ate a setima repeticao. Conclusao: Os exercicios de forca a 85% de 1 RM parecem aumentar significativamente a amplitude de movimento de forma aguda e o crescimento dessa amplitude de movimento tem resposta de dose-efeito.

EJERCICIO DE ALTA INTENSIDAD Y LA FLEXIBILIDAD DE LAS EXTREMIDADES INFERIORES: ESTUDIO DE DOSIS-EFECTO

Introduction: Sports scientists have been studying the phenomenon involving different types of exercises and their influence on other activities. Stretching exercises have a negative influence on muscular strength and power output, as do high intensity or long duration cardiovascular training. Nevertheless, several studies have found the opposite to be true Nevertheless, few investigations have studied the opposite. Objective: To determine whether high intensity power exercise influences muscular flexibility in an acute manner. Methods: A sample of forty-three male and female young adults aged between 18 and 28 years, with a mean age of 22.88 + 3.04 years, who have practiced physical activity for at least six months. To determine flexibility, the sit-and-reach test was used. For the high intensity training, a 45o leg press was used. A 10-rep movement was performed at 85% of 1 RM, in both pre- and post-tests. Statistic analysis was conducted using the ANOVA and Scheffers post-hoc tests, with a level of significance for differences of < 0.05. Results: Comparison of the pre- and post-tests proved to be statistically significant from the baseline from the fourth to the seventh repetitions. Conclusion: Strength exercises at 85% of 1RM seem to significantly increase range of motion in an acute manner, and the growth of this range of motion has a dose-effect response.Introducao: Os cientistas do esporte veem estudando o fenomeno que envolve diferentes tipos de exercicios e sua influencia sobre outras atividades. Os exercicios de alongamento tem influencia negativa sobre a forca e potencia muscular, da mesma forma que o treinamento cardiovascular de longa duracao ou alta intensidade. No entanto, poucas investigacoes tem estudado o oposto. Objetivo: Identificar se o exercicio de alta intensidade tem influencia sobre a flexibilidade muscular de forma aguda. Metodos: Amostra de quarenta e tres jovens adultos do sexo masculino e do sexo feminino entre 18 e 28 anos de idade, com media de idade de 22,88 + 3,04 anos, praticantes de atividade fisica por pelo menos seis meses. Para verificar a flexibilidade, foi utilizado o teste de sentar e alcancar. Para o treinamento de alta intensidade, foi selecionada a pressao de pernas (leg press) em 45o. Foram realizadas 10 repeticoes a 85% de 1 RM, tanto no pre quanto no pos-teste. A analise estatistica foi realizada por ANOVA e testes post hoc de Scheffer, com nivel de significância para diferencas ≤ 0,05. Resultados: A comparacao entre pre e pos-teste mostrou-se estatisticamente significante desde a linha de base, da quarta ate a setima repeticao. Conclusao: Os exercicios de forca a 85% de 1 RM parecem aumentar significativamente a amplitude de movimento de forma aguda e o crescimento dessa amplitude de movimento tem resposta de dose-efeito.

HIGH INTENSITY EXERCISE AND FLEXIBILITY OF THE LOWER LIMBS: DOSE-EFFECT STUDY

Introduction: Sports scientists have been studying the phenomenon involving different types of exercises and their influence on other activities. Stretching exercises have a negative influence on muscular strength and power output, as do high intensity or long duration cardiovascular training. Nevertheless, several studies have found the opposite to be true Nevertheless, few investigations have studied the opposite. Objective: To determine whether high intensity power exercise influences muscular flexibility in an acute manner. Methods: A sample of forty-three male and female young adults aged between 18 and 28 years, with a mean age of 22.88 + 3.04 years, who have practiced physical activity for at least six months. To determine flexibility, the sit-and-reach test was used. For the high intensity training, a 45o leg press was used. A 10-rep movement was performed at 85% of 1 RM, in both pre- and post-tests. Statistic analysis was conducted using the ANOVA and Scheffers post-hoc tests, with a level of significance for differences of < 0.05. Results: Comparison of the pre- and post-tests proved to be statistically significant from the baseline from the fourth to the seventh repetitions. Conclusion: Strength exercises at 85% of 1RM seem to significantly increase range of motion in an acute manner, and the growth of this range of motion has a dose-effect response.Introducao: Os cientistas do esporte veem estudando o fenomeno que envolve diferentes tipos de exercicios e sua influencia sobre outras atividades. Os exercicios de alongamento tem influencia negativa sobre a forca e potencia muscular, da mesma forma que o treinamento cardiovascular de longa duracao ou alta intensidade. No entanto, poucas investigacoes tem estudado o oposto. Objetivo: Identificar se o exercicio de alta intensidade tem influencia sobre a flexibilidade muscular de forma aguda. Metodos: Amostra de quarenta e tres jovens adultos do sexo masculino e do sexo feminino entre 18 e 28 anos de idade, com media de idade de 22,88 + 3,04 anos, praticantes de atividade fisica por pelo menos seis meses. Para verificar a flexibilidade, foi utilizado o teste de sentar e alcancar. Para o treinamento de alta intensidade, foi selecionada a pressao de pernas (leg press) em 45o. Foram realizadas 10 repeticoes a 85% de 1 RM, tanto no pre quanto no pos-teste. A analise estatistica foi realizada por ANOVA e testes post hoc de Scheffer, com nivel de significância para diferencas ≤ 0,05. Resultados: A comparacao entre pre e pos-teste mostrou-se estatisticamente significante desde a linha de base, da quarta ate a setima repeticao. Conclusao: Os exercicios de forca a 85% de 1 RM parecem aumentar significativamente a amplitude de movimento de forma aguda e o crescimento dessa amplitude de movimento tem resposta de dose-efeito.

Muscular Strength and Hydroxyproline Concentration in Urine After Different Flexibility Training Protocols

Muscular Strength and Hydroxyproline Concentration in Urine After Different Flexibility Training Protocols The objective of this study was to evaluate variation in the lumbar spine extension (LSE) muscular strength index and the hydroxyproline (HP) urinary concentrations as a function of flexibility training with maximum intensity (flexibilizing) statically, by proprioceptive neuromuscular facilitation (PNF) and submaximally. The sample population - with an age of 17.13 ± 1.23; body mass of 63.23 ± 6.36 kg; height of 173.62 ± 5.465 cm and body fat percentage of 10 ± 3.62% - comprised 60 male individuals divided randomly into four equal groups: CG (control), StrG (stretching), SFG (static flexibilizing) and PNFG (flexibilizing by PNF). The statistical program SPSS 14.0 for Windows was used to perform a Shapiro Wilk test to verify the normality of the data and Levenes test to analyze the homogeneity of the sample, repeated measures ANOVA for multiple comparisons among groups and the Tukeys HSD Post Hoc test to determine the statistical difference within groups of the variables. A significance level of 95% (p<0.05) was adopted. The results showed a significant difference in LSE between PNFG and CG (D% = 11%; p = 0.029). It can be concluded that the practice of PNF increased strength in the study group. Mišićna Snaga i Koncentracija Hidroksiprolina u Urinu Posle Različitih Protokola za Vežbanje Fleksibilnosti Cilj studije bio je da se odrede varijacije indeksa mišićne snage ekstenzije lumbalnog dela kičme i koncentracije hidroksiprolina u urinu kao funkcija vežbanja fleksibilnosti sa maksimalnim intenzitetom (fleksibilizacija) statično, proprioceptivnom neuromišićnom facilitacijom (PNF) i submaksimalno. Ispitivanu populaciju - prosečne starosti 17,13±1,23; telesne mase 63,23±6,36 kg; visine 173,62±5,465 cm i sa prosečnim procentom telesne masti 10±3,62 % - činilo je 60 muškaraca nasumično podeljenih u 4 jednake grupe: CG (kontrolnu grupu), StrG (istezanje), SFG (statična fleksibilizacija) i PNFG (fleksibilizacija metodom PNF). Statistički program SPSS 14.0 za »Windows« korišćen je za izvođenje testa Shapiro-Wilk kako bi se utvrdila normalnost podataka i homogenost uzorka. Za ponovljena merenja korišćena je ANOVA sa višestrukim poređenjima između grupa a Tukeyjev HSD post hoc test za utvrđivanje statističke razlike u okviru grupa varijabli. Usvojen je nivo značajnosti od 95 % (p<0,05). Rezultati pokazuju značajnu razliku u ekstenziji lumbalnog dela kičme između PNFG i CG (D%=11%, p=0,029). Može se zaključiti da je upražnjavanje PNF pojačalo snagu u proučavanoj grupi.