Cardiovascular safety and effects on peripheral circulation of a leg resistance exercise training in the elderly

对175名老年受试者进行了腿部阻力运动（直腿抬高（SLR）和膝关节伸展（KE））的安全性检查，对31名受试者进行了呼吸引导（缓慢呼气，运动时不屏住呼吸）的有效性检查。对18例冠心病患者行心肌显像检查。在运动过程中没有出现胸部症状。运动期间无缺血性ST改变。约半数受试者在60%1RM运动强度时出现血压过度升高（收缩压bb0 180mmHg）。在呼吸引导下，运动期间血压升高明显降低。腿部阻力运动对于75岁以下的老年人是安全的，运动强度小于60%1RM，并有适当的呼吸指导。在20名75岁以上的老年受试者中，9人（45%）在腿部阻力运动中血压过高，1人（5%）在腿部阻力运动中出现严重的肌肉疼痛。因此，需要仔细的运动处方……更适合75岁以下的老年人。18例患者运动时心肌显像显示8例（44%）存在可逆性灌注缺陷。因此，即使临床上稳定的冠状动脉疾病患者没有心绞痛症状和缺血性st段下降或升高，腿部阻力运动也可能导致心肌缺血。106例受试者参加监督阻力训练（3 ~ 24个月），无心脏事件发生。本文采用近红外光谱法对54例中老年受试者在腿部阻力运动（KE）中运动肌肉的血容量和氧合进行了研究。在运动过程中连续测定总血红蛋白指数（THI）作为血容量指标，并以% TOI评价氧合。THI百分比在运动期间显著增加。血清总胆固醇浓度与%THI呈微弱但显著的负相关。这些结果表明，在中老年受试者中，高胆固醇血症与腿部阻力运动的血容量反应受损有关。% TOI在40%-1RM和60%-1RM之间显著下降，而在60%-1RM和80%-1RM之间没有显著下降。大腿皮肤脂肪厚度和1RM-weight与TOI %变化相关。综上所述，中老年受试者腿部阻力运动时运动肌肉的氧合变化受运动强度的影响。少

Safety of leg-resistance exercise (straight leg raising (SLR) and knee extension (KE)) was examined in 175 elderly subjects and usefulness of respiratory guidance (exhale slowly and not hold one's breath during exercise) was in 31 subjects. Myocardial scintigraphy was performed in 18 patients with coronary artery disease. There were no chest symptoms during the exercise. None had ischemic ST changes during the exercise. Excessive rise in blood pressure (systolic blood pressure>180mmHg) was revealed during 60%1RM exercise intensity in about half subjects. Blood pressure elevation during exercise was significantly lowered by respiratory guidance. Leg-resistance exercise is safe for the elderly less than 75 years with less than 60%1RM exeicise intensity and appropriate respiratory guidance. Of 20 elderly subjects more than 75 years, 9(45%) had excessive blood pressure rise and 1(5%) had severe muscle pain during leg-resistance exercise. Therefore, careful exercise prescription is required … More for the elderly>75 years of age. The myocardial scintigraphy during exercise revealed reversible perfusion defects in 8(44%) of the 18 patients. Thus, leg-resistance exercise can possibly induce myocardial ischemia even though there is absence of anginal symptoms and ischemic ST-segment depression or elevation in patients with clinically stable coronary artery disease. No cardiac events occurred in 106 subjects participated in supervised resistance training program (3〜24 months).The blood-volume and oxygenation in exercising muscles during leg-resistance exercise (KE) was studied with near-infrared spectroscopy in 54 middle aged or elderly subjects. The total hemoglobin index (THI) as the index of blood volume and the oxygenation evaluated by % TOI was measured continuously during exercise. The %THI increased significantly during exercise. There was a weak but significant negative correlation between the serum total cholesterol concentration and the %THI. These results suggested that hypercholesterolemia is associated with impaired blood-volume response to leg-resistance exercise in middle-aged or elderly subjects. The % TOI significantly decreased between 40%-1RM and 60%-1RM, while did not between 60%-1RM and 80%-1RM. The thigh skin fat thickness and 1RM-weight correlated to the %TOI changes. In conclusion, the oxygenation changes in exercising muscles during leg-resistance exercise are influenced by the exercise intensity in middle-aged or elderly subjects. Less