不同锻炼方案对健康男性立位耐力测试中左心室功能的影响

Effect of different exercises on the left ventricle function during orthostatic tolerance test

目的通过超声心动图评估不同训练方式对健康男性立位耐力试验中左室功能的影响。方法25例健康志愿者按报到顺序分为3组。其中两组进行高强度间歇训练（high—intensity interval training，HIT）：冲刺间歇训练组（冲刺组，8人）全力跑10S，重复8次，间歇时间30S；高强度有氧间歇训练组（4×4组，9人）85％最大耗氧量跑4min，重复4次，间歇时间3min。另1组进行持续训练（持续组，8人），锻炼强度为80％最大耗氧量，持续时间30min。以上各组每周均锻炼3次，锻炼8周。分别记录训练前、后立位耐力试验中平卧、立位倾斜即刻及立位倾斜持续15min时的二尖瓣血流频谱舒张早期快速充盈波与舒张晚期缓慢充盈波峰值速度之比[mitral valvular early diastolic inflow velocity／mitral valvular late diastolic inflow velocity，E／A]、组织多普勒成像（tissue Doppler imaging，TDI）模式取样点在二尖瓣环间隔侧二尖瓣环舒张早期和舒张晚期运动速度之比（mitral annular early diastolic velocity／mitral annular late diastolic velocity，E′／A′）、E／E′、TDI-Tei指数。结果20例健康志愿者超声图像满意。冲刺组训练后立位倾斜即刻E′／A′明显大于训练前（1．81±0．17与1．22±0．18，P=0．009），且E′／A′〈2．0。4×4组训练后立位倾斜即刻TDI—Tei明显小于训练前（0．55±0．09与1．07±0．20，P=0．041）；训练后立位倾斜持续15min时E／E′较训练前明显减少（7．22±0．63与9．05±0．43，P=0．037）。连续组训练后平卧时E／A较训练前明显增加（2．28±0．22与1．93±0．17，P=0．034），E／E′较训练前明显减少（5．81±0．61与7．01±0．49，P=0．044）。结论持续训练和HIT方案均可不同程度地改善受试者左心室舒张功能，而HIT以改善受试者立位倾斜试验即刻及过程中的左心室舒张功能为主，且4×4组训练方式可同时改善左心室整体功能。

Objective To assess the effect of different exercises on left ventricle function by echocardiography in orthostatic tolerance test. Methods Twenty-five healthy males were assigned to 3 groups by the registration order. Two groups underwent high-intensity interval exercises （HIT）： sprint group （n= 8） took 10 s-running with full power for 8 times with 30 s interval, and high- intensive aerobic group （n=9, 4 × 4 exercise group） took 4 min-running with 85% maximal oxygen consumption for 4 times with 3 rain interval. One group underwent continuous exercises： continuous group （n = 8） ran with 80% maximal oxygen consumption for 30 rain. All groups did exercises 3 times/week for 8 weeks. Their echocardiography was monitored in the orthostatic tolerance test respectively under lain low, instant vertical tilt and 15 rain continued tih conditions before and after the 8 weeks-exercise. Parameters analyzed included the ratio of mitral annular early diastolic velocity and mitral annular late diastolic velocity （E/A）, mitral annular early velocity and late velocity （E′/A′） and E/E′ at mitral septal level. TDI-Tei was obtained by tissue Doppler imaging. Results All ultrasonic images of 20 healthy males were good enough for analysis. The E′/A′ of the sprint group in instant vertical tilt test was higher after the exercise than that before the exercise （1.81±0.17 vs 1.22±0.18, P=0. 009） and E′/A′〈2.0. The TDI-Tei of the 4×4 exercise group in instant vertical tilt test was significantly decreased after the exercise than that before the exercise （0. 55±0. 09 vs 1.07 ± 0.20, P=0. 041）, and their E/E′ in 15 min continued tilt test was significantly decreased than that before the exercise （7.22±0.63 vs 9.05±0.43, P=0. 037）. The E/A of the continuous group in lain low test was higher before exercise than that after exercise （2.28±0.22 vs 1.93±0.17, P=0. 034）, and their E/E′ was significantly decreased than that before the exercise （5.81±0.61 vs 7.01 ± 0.49, P=0. 044）. Conclusions Both continuous and HIT exercises improve the diastolic function of left ventricle to a certain degree, and HIT has more effects on the function improvement in the instant and the process of orthostatic tolerance test. The style of 4 × 4 exercise improves the TDI-Tei of left ventricle function.