单次低强度骑车和跑步对健康男生动脉硬度的影响

Influence of Acute Low Intensity Cycling and Treadmill on Arterial Stiffness of Healthy Male Students

观察和比较单次低强度骑车和跑步对健康男生动脉硬度的短时影响,并探索跑步坡度的可能作用。方法:采用随机均衡交叉自身对照设计,16名健康男生的年龄为(21.8±0.4)岁,按空白对照方案(non-exercise control trial,CON)、骑车方案(cycle trial,CYC)、0坡度跑步方案(treadmill trial at 0,TM0)和18%坡度跑步方案(treadmill trial at 18%,TM18)进行实验。受试者均在运动前进行基线(baseline,BL)动脉硬度测定,然后进行持续30min的单次运动,强度均控制在35%心率储备。运动结束后即刻(0min)和结束后40min对动脉硬度进行重复测定。动脉硬度用心-踝血管指数(cardio-ankle vascular index,CAVI)来评价,用每个方案中CAVI相对于其基线的变化(ΔCAVI)进行统计分析。结果:CON方案中ΔCAVI在BL、0min和40min时分别为(0.0±0.0)(0.1±0.1)和(0.0±0.1),变化未见显著性。CYC方案中运动后即刻ΔCAVI从基线(0.0±0.0)明显下降至(-1.1±0.1),休息40min基本恢复至基线(-0.2±0.1)。虽然TM0和TM18方案中运动结束后即刻ΔCAVI出现幅度类似于CYC的下降,但在休息40 min后ΔCAVI仍均维持在较低水平(-0.6±0.1,P<0.05vs.CON和CYC)。TM0和TM18方案之间则无明显差别。结论:在相同靶心率的前提下,骑车和跑步均能明显降低动脉硬度,但跑步对动脉硬度的影响优于骑车。相同靶心率跑步中,改变坡度对动脉硬度无影响。

Objective：To compare the acute arterial stiffness response to treadmill and cycle exercise at the same relative low intensity in healthy male students,and to explore the effect of running slope.Methods：Sixteen healthy male students （21.8±0.4 years） underwent 4 trials in a randomized balanced self-control crossover design：non-exercise control （CON）,cycle exercise （CYC）,treadmill exercise trial at 0 （TM0） and at 18% slope （TM18）.All exercise lasted 30 min at the intensity corresponding to 35% heart rate reserve.Arterial stiffness in cardio-ankle vascular index （CAVI） was measured at baseline （BL）,immediately after （0 min） and 40 min after exercise in exercise trials,and at corresponding time points in CON trial.ΔCAVI,the change from its baseline in the same trial,was used for statistical analysis.Results：There were no significant ΔCAVI changes with time in CON trial （0.0±0.0,0.1±0.1,0.0±0.1 at BL,0 and 40 min,respectively）.ΔCAVI in CYC trial decreased immediately after exercise and returned to baseline at 40 min （0.0±0.0,-1.1±0.1,-0.2±0.1 at BL,0 and 40 min,respectively）.TM0 elicited significant ΔCAVI reduction from 6.2±0.2 at baseline to 5.5±0.2 immediately after exercise,and reverted to 5.7±0.1 at 40 min,maintaining significant difference to its baseline.TM0 trial （0.0±0.0,-1.2±0.1,-0.6±0.1,at BL,0 and 40 min,respectively）,and in TM18 trial （0.0±0.0,-1.0±0.1,-0.6±0.1,at BL,0 and 40 min,respectively）.Conclusion：Treadmill exercise induced greater arterial stiffness improvement than cycling.Treadmill slope had no influence on arterial stiffness response to exercise.