The acute effect of cryotherapy on muscle strength and shoulder proprioception

• Autor(a) principal: Torres, Rui
• Data de Publicação: 2016
• Outros Autores: Silva, Filipa, Pedrosa, Vera, Ferreira, João, Lopes, Alfredo
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10400.22/9409

A common intervention used by clinicians, cryotherapy poses several benefits in managing acute injuries. However, cooling muscle tissue can interfere with muscular properties and the sensory-motor system. The aim of this study was analyse the influence of cryotherapy with a crushed-ice pack on shoulder proprioception concerning joint position sense, force sense, the threshold for detecting passive movement, and maximal force production. A randomised, double-blind controlled trial. Participants: 48 healthy women aged 22.6±0.4 years with a mean body mass index of 22.8 ±0.37 kg/m2 and percentage of body fat of 15.4±1.5%. In the experimental group, a crushed-ice pack was applied to the shoulder for 15 min, whereas participants in the control group applied a sand of bag at skin temperature, also for 15 min. An isokinetic dynamometer was used to assess maximal voluntary contraction, force sense, joint position sense, and the threshold for detecting passive movement. Paired sample t-tests revealed that maximal voluntary isometric contraction decreased significantly after cryotherapy (p ≤ .001), or approximately 10% of the reduction found in both muscular groups assessed. Shoulder position sense (p < .001) and the threshold for detecting passive movement (p = .010 and p=.009 for lateral and medial shoulder rotator muscles, respectively) also suffered significant impairment. Nevertheless, no significant differences emerged in force sense at 20% and 50% of maximal force reproduction (p = .410 and p = .097 for lateral rotator muscles at 20% and 50%, respectively; and, p = .197 and p = .090 for medial rotator muscles at 20% and 50%, respectively). Applying a crushed-ice pack to the shoulder for 15 min negatively affected muscle strength and impaired shoulder proprioception by decreasing joint position sense and the threshold for detecting passive movement.