摘要
目的:冬泳运动是一项冷环境中强度较大的运动。机体代谢率高,耗氧量增加。长期规律的冬泳运动被认为能促进血液循环,改善机体功能状态,提高免疫力,增强体质,进而预防各种老年性疾病的发生。但是近年来关于冬泳造成猝死的病例很多,大部分为心脑血管和血栓栓塞性疾病。目前关于机体对冷应激和冷适应运动的变化,以及机体对不同温度和运动量的反应研究甚少。因此,需更加深入地认识冬泳运动对机体的影响和作用。本文以前人关于不同水温和运动时间下冬泳运动机体的反应实验为基础资料,采用大鼠冷应激和冷适应游泳方法建立冬泳动物模型,分析这两种冬泳运动模式对机体自由基代谢、ATP酶活性和Ca ~(2+)含量的影响,深入认识冷应激和冷适应运动对机体体能状态的双向作用,为冷适应运动时机体的塑性改变提供基本数据,为广大的冬泳爱好者提供冬泳健身的科学依据,进而预防各种冬泳运动性损伤的发生。
方法:健康雄性Sprague-Dauley(SD)大鼠30只,随机分成三组,对照组(n=10),冷应激运动组(n=10),冷适应运动组(n=10)。对照组:实验第7周处死。冷应激运动组:第6周末进行适应性游泳训练3天,每天一次,水温30℃,时间15min。第7周在8℃水温中运动一次,时间8min,运动后即刻处死。冷适应运动组:适应性游泳训练3天,每天一次,水温30℃,时间15min。正式训练:每天一次,起始水温30℃,时间40min,从第二天起水温每天下降2℃,运动时间每天缩短3min,每周训练6天,持续2周。从第3周起保持在水温为10℃,训练时间为5min水平,训练6周。第7周在8℃水温中运动一次,时间8min,,运动后即刻处死。各组大鼠每周称重一次。处死后取心、脑组织匀浆,离心,检测心、脑组织的MDA含量、SOD活性、Na+ -K+ -ATP酶、Ca ~(2+)-ATP酶活性和Ca ~(2+)含量等指标。
结果:
1大鼠体重变化:从实验第3周至结束,冷适应运动组体重均值均显著低于对照组和冷应激运动组(P<0.01);对照组与冷应激运动组没有统计学差异(P>0.05)。实验结束时,对照组和冷应激运动组大鼠体重增长率(52.6%,51.1%)较冷适应运动组(27.0%)显著升高(P<0.01)。
2氧化应激指标:冷应激运动组心,脑组织MDA含量(2.45±0.30 nmol/mgprot,9.65±0.75 nmol/mgprot)较对照组显著升高(P<0.01);冷适应运动组心,脑MDA含量(1.82±0.29 nmol/mgprot ,6.68±0.78nmol/mgprot)与对照组没有差异性(P>0.05),较冷应激运动组显著降低(P<0.01)。冷应激运动组心,脑组织SOD活力(95.22±29.92 U/mgprot,153.21±10.17 U/mgprot)较对照组显著降低(P<0.01);冷适应运动组心,脑组织SOD活力(278.80±25.50 U/mgprot ,190.27±12.55 U/mgprot)与对照组没有差异性(P>0.05),较冷应激运动组显著升高(P<0.01)。3ATP酶活性和Ca ~(2+)含量:冷应激运动组心,脑组织Na + -K + -ATP酶活性(1.58±1.14μmolpi/mgprot/hour,2.13±0.32μmolpi/mgprot/hour)较对照组显著降低( P < 0.01 ) ;冷适应运动组心,脑组织Na + -K + -ATP酶活性(1.98±0.15μmolpi/mgprot/hour ,2.90±0.37μmolpi/mgprot/hour )与对照组没有差异性(P>0.05),较冷应激运动组显著升高(P<0.01)。冷应激运动组心,脑组织Ca ~(2+)-ATP酶活性(2.35±0.20μmolpi/mgprot/hour ,1.33±0.19μmolpi/mgprot/hour)较对照组显著降低(P<0.01);冷适应运动组心,脑组织Ca ~(2+)-ATP酶活性(2.67±0.23μmolpi/mgprot/hour ,1.72±0.21μmolpi/mgprot/hour)与对照组没有差异性(P>0.05),较冷应激运动组显著升高(P<0.01)。冷应激运动组心,脑组织Ca ~(2+)含量(95±6.01μmol/gprot,34±5.81μmol/gprot)较对照组升高(P<0.05)冷适应运动组心,脑组织Ca ~(2+)含量(89±5.67μmol/gprot ,29±4.85μmol/gprot)与对照组没有差异性(P>0.05),较冷应激运动组降低(P<0.05)。4MDA与ATP酶的相关性检验:心脏MDA与Na + -K+ -ATP酶相关系数是-0.726(P<0.01),成显著负相关;与Ca ~(2+)-ATP酶相关系数是—0.387(P<0.05),成负相关。脑组织MDA与Na+-K+-ATP酶相关系数是—0.697(P<0.01),成显著负相关;与Ca ~(2+)-ATP酶相关系数是—0.712(P<0.01),成显著负相关。结论:1长期的冷适应游泳对于控制体重有很好的效果,这在降低肥胖相关疾病的发病率方面可以起到积极的作用。
2冷适应游泳能明显降低脂质过氧化损伤,提高抗氧化系统的能力,使机体对冷水运动应激的适应性增强。
3 ATP酶活性下降和细胞钙超载与氧化应激造成的自由基损伤相关,冷适应游泳能通过长期的抗氧化适应改善ATP酶活性,维持组织正常钙含量。
Objective: Winter swimming is an exercise with high intensity in cold environment. During this exercise, metabolism rate of the body raises and oxygen consumption increases. Long-term regular winter swimming exercise is thought to promote blood circulation, improve the functional status of the body, improve immunity, enhance physical fitness, and thus prevent age-related diseases. But in recent years cases of sudden death caused by winter swimming have been increased, these deaths are mainly due to cardiac or cerebrovascular causes and thromboembolic diseases. There are very little reach about the changes of the body under cold stress and cold adaptation exercise and body reaction to different temperature and exercise intensity. Therefore, we need more in-depth research into the impact of winter swimming on body function. In this article, we used the response of the body in winter swimming under different water temperature and time as the experimental data , and established animal model of winter swimming using the method of cold stress and cold adaptation swimming in rats , analyzing the effect of two patterns of winter swimming exercise on radical metabolism , ATP activity and Ca ~(2+)content of the body, understanding the double role of cold stress and cold adaptation exercise on the physical state of the body, providing basic datas for the changes of body under cold adaptation exercise , and providing the scientific basis about winter swimming fitness for enthusiasts, Thus to prevent injuries caused by winter swimming.
Methods: 30 Male Sprague-Dauley (SD) rats were randomly divided into three groups, control group (n = 10), cold stress sport group (n = 10), cold-adapted sport group (n = 10). Control group: NO training and were killed at the 7nd week . Cold stress sport groups: At the end of the 6 nd week, adaptive swimming training 3 days, once a day, water temperature 30℃, 15min. At the 7nd Week swimmed once, water temperature 8℃, 8min and were killed immediately after exercise. Cold-adapted sport groups: adaptive swimming 3 days, once a day, water temperature 30℃, 15min. Formal training: starting temperature 30℃, 40min, once a day. but from the 2th day, the temperature was decreased 2℃,and the exercise time was shorten 3min each day , trained 6 days a week for 2 weeks. From the 3thweek, the temperature was kept at 10℃and 5min for 4 weeks. At the 7 nd Week swimmed once, water temperature 8℃, 8min and were killed immediately after exercise. All the rats weighed once a week. After the execution, take the tissue of hearts and brains. Treat the tissues by methods of homogenate and centrifugation. Test the following indexes: MDA content, SOD activity, Na-K-ATPase activity, Ca-ATPase activity and Ca ~(2+)content.
Results:1 Weight change: From the 3thweek to the end of the experiment, the mean of body weight in the cold-adapted sport group is significantly lower than that in the control group and the cold stress sport group (P <0.01);But there are no significant differences between the control group and the cold stress sport group(P>0.05). At end of the experiment, weight growth rate of the control group and the cold stress sport group (52.6%, 51.1%) is significantly higher than the cold-adapted sport group (27.0%) (P <0.01).
2 Oxidative stress indicators: The MDA content of the heart and the brain in the cold stress sport group (2.45±0.30 nmol / mgprot, 9.65±0.75 nmol / mgprot) is significantly higher than that in the control group (P <0.01); The MDA content of the heart and the brain in the cold-adapted sport group(1.82±0.29nmol/mgprot, 6.68±0.78nmol/mgprot) has no difference with that in the control group (P> 0.05), but is significantly lower than that in the cold stress sport group (P <0.01). The SOD activity of the heart and the brain in the cold stree sport group(95.22±29.92 U/mgprot,153.21±10.17 U/mgprot)is significantly lower than that in the control group (P <0.01); The SOD activity of the heart and the brain in the cold-adapted sport group(278.80±25.50 U/mgprot ,190.27±12.55 U/mgprot)has no difference with that in the control group (P> 0.05), but is significantly higher than that in the cold stress sport group (P <0.01).
3 The ATPase activity and the Ca ~(2+)content : The Na + -K + -ATPase activity of the heart and the brain in the cold stree sport group(1.58±1.14μmolpi/mgprot/hour,2.13±0.32μmolpi/mgprot/hour)is significantly lower than that in the control group (P <0.01); The Na + -K + -ATPase activity of the heart and the brain in the cold-adapted sport group; (1.98±0.15μmolpi/mgprot/hour,2.90±0.37μmolpi/mgprot/hour)has no difference with that in the control group (P>0.05), but is significantly higher than that in the cold stress sport group (P <0.01).The Ca ~(2+)-ATPase activity of the heart and the brain in the cold stree group ( 2.35±0.20μmolpi/mgprot/hour ,1.33±0.19μmolpi/mgprot/hour)is significantly lower than that in the control group (P <0.01); The Ca ~(2+)-ATPase activity of the heart and the brain in the cold-adapted sport group ( 2.67±0.23μmolpi/mgprot/hour , 1.72±0.21μmolpi/mgprot/hour ) has no difference with that in the control group (P>0.05), but is significantly higher than that in the cold stress sport group (P <0.01). The Ca ~(2+)content of the heart and the brain in the cold stress sport group(95±6.01μmol/gprot,34±5.81μmol/gprot)is higher than that in the control group (P <0.05); The Ca ~(2+)content of the heart and the brain in the cold-adapted sport group(89±5.67μmol/gprot ,29±4.85μmol/gprot)has no difference with that in the control group (P> 0.05), but is lower than that in the cold stress sport group (P <0.05).
4 Correlation tests between MDA and ATPase: In the heart correlation coefficient between MDA and Na + -K + -ATPase is -0.726(P<0.01),shows negative correlation;In the heart correlation coefficient between MDA and Ca ~(2+)-ATPase is -0.387(P<0.05),shows negative correlation. In the brain correlation coefficient between MDA and Na + -K + -ATPase is -0.697(P<0.01),shows negative correlation;In the brain correlation coefficient between MDA and Ca ~(2+)-ATPase is -0.712(P<0.01),shows negative correlation.
Conclusions:1 Long-term cold adapted swimming is very effective for weight control, and this could play a positive role on reducing the incidence of obesity-related diseases.
2 Cold adapted swimming can significantly reduce damages caused by the lipid peroxidation, improve the capacity of antioxidant system, enhance the adaptability of exercise in cold water stress.
3 The fall in ATP activity and cell calcium overload is related to free radical damage caused by oxidative stress. Through long-term antioxidant adaptation, cold adapted swimming can improve the activity of ATP and maintain normal calcium content in tissue.
引文
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