Glazier Douglas Stewart
Department of Biology, Juniata College, Huntingdon, PA, 16652, USA.
J Comp Physiol B. 2009 Oct;179(7):821-8. doi: 10.1007/s00360-009-0363-3. Epub 2009 Apr 22.
Metabolic rate is commonly thought to scale with body mass (M) to the 3/4 power. However, the metabolic scaling exponent (b) may vary with activity state, as has been shown chiefly for interspecific relationships. Here I use a meta-analysis of literature data to test whether b changes with activity level within species of ectothermic animals. Data for 19 species show that b is usually higher during active exercise (mean +/- 95% confidence limits = 0.918 +/- 0.038) than during rest (0.768 +/- 0.069). This significant upward shift in b to near 1 is consistent with the metabolic level boundaries hypothesis, which predicts that maximal metabolic rate during exercise should be chiefly influenced by volume-related muscular power production (scaling as M (1)). This dependence of b on activity level does not appear to be a simple temperature effect because body temperature in ectotherms changes very little during exercise.
代谢率通常被认为与体重（M）的3/4次方成正比。然而，代谢标度指数（b）可能会随活动状态而变化，这主要已在种间关系中得到证实。在此，我通过对文献数据进行荟萃分析，来检验b在变温动物物种内是否会随活动水平而改变。19个物种的数据表明，b在主动运动期间（平均值±95%置信区间=0.918±0.038）通常高于休息期间（0.768±0.069）。b显著上移至接近1与代谢水平边界假说相符，该假说预测运动期间的最大代谢率应主要受与体积相关的肌肉力量产生的影响（标度为M(1)）。b对活动水平的这种依赖性似乎并非简单的温度效应，因为变温动物的体温在运动期间变化很小。
