数九寒冬进行体育锻炼,不但可提高人体御寒和抗病能力,而且能培养人的意志,为收到预期效果,锻炼时必须注意“四防”。一防运动损伤。冬季,人的肌肉和韧带受到寒冷的刺激后,会反射性地引起血管收缩,粘滞性增加,弹性和伸展度降低,各关节活动幅度减少,神经系统对肌肉的协调指挥能力也有所下降。一旦从事剧烈运动,稍有不慎,常会造成肌肉、肌腱、韧带等软组织损伤。因此,锻炼前应做好暖身或腰、腿、关节等 Number nine cold winter sports, not only can improve the body warm and disease resistance, but also to cultivate the will of the people, in order to receive the desired results, exercise must pay attention to “four defenses.” An anti-sports injury. In winter, when people’s muscles and ligaments are cold stimulated, their vasoconstriction and viscosity increase reflexively, their elasticity and extensibility decrease, their joint activity decreases, and the nervous system’s command and coordination ability to muscle decreases. Once engaged in strenuous exercise, a little carelessness, often resulting in muscle, tendon, ligament and other soft tissue injury. Therefore, before exercise should be warm or waist, legs, joints and so on