Thompson H J, Westerlind K C, Snedden J, Briggs S, Singh M
Division of Laboratory Research, AMC Cancer Research Center, Denver, CO 80214, USA.
Carcinogenesis. 1995 Aug;16(8):1783-6. doi: 10.1093/carcin/16.8.1783.
The objective of this experiment was to evaluate the effects of treadmill exercise on tumor induction in an experimental model for breast cancer. Female F-344 rats were injected i.p. with 50 mg MNU/kg body wt at 50 and 57 days of age. Animals were assigned to one of five groups: sham exercise or 35% or 70% maximal treadmill running intensity for 20 or 40 min/day, 5 days per week. These work rates represent an exercise intensity level generally considered insufficient to improve cardiovascular fitness (35% maximal intensity) or an aerobic level of exercise sufficient to improve cardiovascular fitness in humans (70% maximal intensity). Rats were exercised for 3 months following carcinogen administration at which time the experiment was terminated. Mammary cancer incidence was reduced by as much as 37% and cancer multiplicity by < 60% at the highest exercise intensity. Unexpectedly, the degree of protection against cancer was proportional to the intensity but not to the duration of exercise.
本实验的目的是在乳腺癌实验模型中评估跑步机运动对肿瘤诱导的影响。雌性F-344大鼠在50日龄和57日龄时经腹腔注射50 mg MNU/kg体重。动物被分为五组之一：假运动组或每天以35%或70%的最大跑步机跑步强度运动20或40分钟，每周5天。这些工作强度代表了一般认为不足以改善心血管健康的运动强度水平（35%最大强度）或足以改善人类心血管健康的有氧运动水平（70%最大强度）。在给予致癌物后，大鼠进行3个月的运动，此时实验终止。在最高运动强度下，乳腺癌发病率降低了多达37%，癌症多发性降低了<60%。出乎意料的是，对癌症的保护程度与运动强度成正比，而与运动持续时间无关。
