Petrofsky J S, Lind A R
J Appl Physiol. 1975 Oct;39(4):639-42. doi: 10.1152/jappl.1975.39.4.639.
Four male subjects were examined to assess the relationship of body fat content to deep muscle temperature and the endurance of a fatiguing isometric handgrip contraction at a tension set at 40% MVC. Muscle temperature was altered by the immersion of the forearm in water at temperatures varying from 7.5 to 40 degrees C. In all subjects, there was a water bath temperature above and below which isometric endurance decreased markedly; the difference among individuals was solely accounted for by the individual's body fat content. Thus, subjects with higher body fat content required lower bath temperatures to cool the forearm musculature to its optimum temperature, which we found to always be approximately 27 degrees C measured 2 cm perpendicularly to the skin in the belly of the brachioradialis muscle. Further, in one subject, we found that a reduction in this subject's body fat content resulted in a corresponding increase in the water bath temperature necessary to cool his muscles to their optimum isometric performance. The data demonstrate the striking insulative power of the thin layer of fat around the forearm in man in protecting shell tissues from cold exposure.
对四名男性受试者进行了检查，以评估身体脂肪含量与深部肌肉温度以及在40%最大随意收缩（MVC）张力下疲劳性等长握力收缩耐力之间的关系。通过将前臂浸入温度在7.5至40摄氏度之间变化的水中来改变肌肉温度。在所有受试者中，存在一个高于和低于该温度的水浴温度，在此温度下等长耐力会显著下降；个体之间的差异完全由个体的身体脂肪含量决定。因此，身体脂肪含量较高的受试者需要较低的水浴温度来将前臂肌肉组织冷却至其最佳温度，我们发现该最佳温度在桡侧腕长伸肌肌腹垂直于皮肤2厘米处测量时始终约为27摄氏度。此外，在一名受试者中，我们发现该受试者身体脂肪含量的降低导致将其肌肉冷却至最佳等长性能所需的水浴温度相应升高。数据表明，人体前臂周围的薄层脂肪在保护表层组织免受寒冷暴露方面具有显著的绝缘能力。
