Acute static muscle stretching improves manual dexterity in young men

Abstract

OBJECTIVE:This study aimed to evaluate the influence of acute muscle stretching on manual function. METHODS:The sample consisted of 10 untrained men in a randomized, four test session cross-over experimental design. Each session was composed of only one of two protocols: a) control, or b) single series of passive static stretching; followed by either Minnesota Hand dexterity test or hand grip strength test with eletromyographical recording of reaction time. For data comparison, the Student T-test with significance level of p ≤ 0.05 was used. RESULTS: Manual dexterity increased after stretching for both placing and turning tests, with no changes in hand grip strength or reaction time. CONCLUSION:The results show that a 30 second static stretch of the hand decreases time to complete the Minnesota Hand Dexterity test without affecting handgrip strength or hand reaction time; thus it improves manual dexterity of young untrained men. KEYWORDS:Muscle stretching, motor skills, reaction time. ■ INTRODUCTIONStretching exercises are often prescribed for persons with reduced motor skills or range of motion. Several reports describe this exercise technique as a necessary activity for better performance in daily life activities.1-4 However, muscle stretching seems to evoke neural and mechanical adaptations that reduce strength, reaction time and body balance; 3,5-7 it also affects the responsiveness of relevant afferent structures, such as muscle spindles 8 and Golgi tendon organs, 9 which are important structures in the regulation of motor commands.Manual dexterity, handgrip strength and reaction time are important components to assess hand function, which relate to better quality of daily life 1,10 and recreational activities; 2,11 they also act as indicators of cognitive and exercise performance 12,13 and are determinant factors in the ability to manipulate objects.14 Additionally, manual dexterity and handgrip strength are closely interdependent, in an interaction known as strength-dexterity trade-off. 15Manual dexterity is also related to the central nervous system, since the cortex receives information from several proprioceptors 8,16 to modulate manual motor tasks increasing movement efficiency.14,17-19 Hence, if muscle stretching does interfere with these factors it could alter the ability to manipulate objects. Because several sports, such as boxing, 20 handball, 21 basketball, 22 and many non-sporting activities such as musical performance 23 require agility and manual dexterity, the assessment of hand function is essential for the development of training techniques and functional rehabilitation of hand movements. However, there is a lack of knowledge about the effect of static stretching on manual dexterity. We hypothesized that muscle stretching would interfere with these factors and consequently alter hand dexterity.The purpose of this study was to understand the effect of static stretching on manual dexterity, providing evidence for health professionals seeking to prescribe stretching exercises safely and effi...

Influência do alongamento muscular sobre o tempo de reação manual

“…Behm et al (37) descreveram relação dose-resposta, pois o menor déficit de desempenho estava associado ao menor volume aplicado (estiramento <60s de duração) por grupo muscular. Estudo recente do nosso grupo avaliou o efeito de apenas 30s de AE dos principais músculos flexores de punho e dedos em homens saudáveis, e esse volume não exerceu qualquer interferência sobre o TRM (38). Possivelmente, o alongamento realizado por pouco tempo (e.g.…”