Comparison betweent the Effects of Swimming and Treadmill-Based Aerobic Training Protocols in Diabetic Rats

Abstract Background: Type 1 diabetes mellitus (DM1) can cause damage to several physiological systems. Objectives: To compare and characterize the effects of aerobic exercise training (ET) performed by swimming with those of ET performed on a treadmill on the skeletal muscle and heart of rats with DM1. Methods: 41 male Wistar rats were randomized into four groups: nondiabetic control (CTR), diabetic control (DMC), diabetic trained on the treadmill (DMT), and diabetic trained by swimming (DMS). The trained groups performed aerobic exercise training for 8 weeks, 5 times a week, 60 min per day. Exercise tolerance, blood glucose, body weight, wet weight of the skeletal muscles and left ventricle (LV), muscle glycogen, cross-sectional area of skeletal muscles, and cross-sectional diameter and collagen volume fraction of the LV were evaluated. Results: The results were expressed as mean ± standard deviation of the mean and submitted to two-way ANOVA with post-hoc Bonferroni test. Aerobic ET protocols applied to animals with DM1, regardless of the ergometer, showed satisfactory results (p < 0.05) when compared to the control groups: improved exercise tolerance, increased glycogen content of the soleus and extensor digitorum longus (EDL) muscles and increased cross-sectional diameter of the left ventricular cardiomyocytes. In some variables, such as exercise tolerance and cross-sectional area of the soleus and EDL muscles, DMT showed better results than DMS (p < 0.05). On the other hand, DMS showed increased cross-sectional diameter of cardiomyocytes when compared with the DMT group. Conclusion: Both aerobic ET protocols offered benefits to animals with diabetes; however, due to the specific characteristics of each modality, different physiological adaptations were observed between the trained groups.

摘要
背景：1型糖尿病（Type 1 diabetes mellitus, DM1）可对多个生理系统造成损伤。
研究目的：对比并表征游泳有氧运动训练（aerobic exercise training, ET）与跑台有氧运动训练对1型糖尿病大鼠骨骼肌与心脏的影响。
方法：将41只雄性Wistar大鼠随机分为4组：非糖尿病对照组（CTR）、糖尿病对照组（DMC）、跑台训练糖尿病组（DMT）以及游泳训练糖尿病组（DMS）。训练组大鼠接受为期8周、每周5次、每次60分钟的有氧运动训练。检测指标涵盖运动耐力、血糖水平、体质量、骨骼肌与左心室（left ventricle, LV）湿重、肌糖原含量、骨骼肌横截面积，以及左心室心肌细胞横径与胶原容积分数。
结果：结果以平均值±标准差表示，采用双因素方差分析（two-way ANOVA）结合Bonferroni事后检验进行统计分析。与对照组相比，无论采用何种运动训练器械，针对1型糖尿病大鼠的有氧运动训练方案均取得了满意效果（p < 0.05）：运动耐力得以提升，比目鱼肌与趾长伸肌（extensor digitorum longus, EDL）的糖原含量升高，左心室心肌细胞横径增大。在部分指标中，如运动耐力、比目鱼肌与趾长伸肌横截面积，跑台训练组（DMT）的效果优于游泳训练组（DMS）（p < 0.05）；而游泳训练组（DMS）的心肌细胞横径则显著大于跑台训练组（DMT）。
结论：两种有氧运动训练方案均对糖尿病大鼠产生了有益效果，但由于两种训练模式的固有特性差异，训练组间观察到了不同的生理适应性变化。