Effects of temperature on electromyogram and muscle function

Abstract

The effects of 30 min of cooling (15 degrees C water) and warming (40 degrees C water) on arm muscle function were measured. A reference condition (24 degrees C air) was included. Of nine young male subjects the maximal grip force (Fmax), the time to reach 66% of Fmax (rate of force buildup) and the maximal rhythmic grip frequency were determined, together with surface electromyographic activity (EMG) of a forearm muscle (flexor digitorum superficialis). The results showed that in contrast to warming, cooling resulted in a significant decrease of 20% in the Fmax and a significant 50% decrease in force build-up time and the maximal rhythmic grip frequency. The relationship between the root mean square value (rms) of the EMG and the static grip force did not change due to temperature changes. The median power frequency (MPF) in the power spectrum of the EMG signal decreased by 50% due to cooling but remained unchanged with heating. During a sustained contraction at 15% of Fmax (Fmax depending on the temperature) the increase in the rms value with contraction time was 90% larger in the warm condition and 80% smaller in the cold condition compared to the increase in the reference condition. The MPF value remained constant during the warm and reference conditions but in the cold it started at a 50% lower value and increased with contraction time.(ABSTRACT TRUNCATED AT 250 WORDS)

Hand-skin temperature and tracking performance

“…As a result, the blood flow to the extremities is reduced even when the hand is exposed to mildly cold temperatures such as 15-25 0 C. (Daanen, 1997). The reduction in blood flow may be the cause for losses in tactile sensitivity , reduced manual performance, grip strength (Holewijn and Heus, 1992;Giesbrecht et al, 1995;Geng 2001, Powell et al, 2000 and increased risk of accidents (Enander, 1984; 4 Havenith et al, 1995;Heus et al, 1995;Geng et al, 2001). Morton and Provins (1960) have found that tactile sensitivity is an L-shaped function of skin temperature and that each individual has a relatively sharp critical temperature at which performance deteriorates significantly.…”

Efeitos da crioterapia e facilitação neuromuscular proprioceptiva sobre a força muscular nas musculaturas flexora e extensora de joelho

“…Em estudo realizado com seres humanos, Kubo et al 11 relatam que a imersão em água fria fez com que o valor da contração voluntária máxima se reduzisse após o procedimento, mas não encontraram alteração significativa nas propriedades mecânicas dos músculos e tendões avaliados. Outros estudos relatam a redução na temperatura muscular como fator determinante na diminuição da força muscular 12,13 .…”

The Short and Long Term Effects of Tibialis Anterior Local Cooling on Dorsiflexion Force

“…The authors identify the decrease in performance of strength tests (vertical jump and shuttle run), but the cooling method was leg immersion and it was applied for 20 minutes. Holewijn and Heus (1992) also observed a fall in the maximal grip force after 30 min of local cooling (15°C), and Oksa et al (1997) found reduced maximal muscle performances during dynamic exercise performed at a lowered room air temperature (10-5°C). All cited studies are in agreement with the reduction of strength after cooling, despite the different cooling methods have been used (i.e., immersion and environment exposure).…”

“…When ice packs are applied over the muscle belly it leads to the reduction of skin and muscle temperatures resulting in changes in the Unauthenticated Download Date | 5/10/18 2:36 AM physiological proprieties of the muscle (Castle et al 2006;Petrofsky & Laymon, 2005;Rutkove, 2001). It has been shown that local muscle cooling may influence muscle resistance (Castle et al, 2006;Verducci, 2000) and force production (Oksa 2002;Oksa et al, 1997;Holewijn & Heus, 1992).…”

“…It is important to note that the different methods of cooling (i.e., ice pack or immersion) may cause different motor output responses, especially because during immersion not only a specific muscle has its temperature lowered but normally several muscles and joints. Immersion has been extensively used in scientific studies (Petrofsky & Laymon, 2005;Douris et al, 2003;Cross et al, 1996;Holewijn & Heus, 1992;Coppin et al, 1978;Johnson & Leider, 1977), but during sports competitions and rehabilitation programs local cooling is much more common (Richendollar et al, 2006;Zemke et al, 1998).…”