Pilmanis A A, Olson R M, Fischer M D, Wiegman J F, Webb J T
High Altitude Protection Flight Stress Protection Division, Brooks AFB, TX 78235-5104, USA.
Aviat Space Environ Med. 1999 Jan;70(1):22-9.
It has been known since World War II that exercise at altitude increases incidence of decompression sickness (DCS). However, data on the effects of specific exercise types at altitude are lacking. This research focused on the relative hazards of exercise without motion (isometric, straining) vs. dynamic exercise involving motion. The study also compared arm vs. leg exercise.
There were 32 healthy male subjects exposed, while resting, to 29,500 ft (8992 m) for 4 h or until DCS occurred, at which time they were brought to ground level. If the subject developed DCS on this exposure, he was exposed in successive months to lower altitudes, using the same procedure, until the subject was free of symptoms for the 4-h exposure. At this symptom-free altitude, as low as 20,000 ft (6096 m), the subject performed isometric arm, isometric leg, dynamic arm and dynamic leg exercises at less than 10% of maximal oxygen consumption, each during separate exposure months. Precordial venous gas emboli (VGE) were monitored every 20 min during each exposure with a Hewlett-Packard SONOS 1000 Echo Imaging System.
Dynamic arm, dynamic leg, isometric arm, and isometric leg exercise induced DCS in 50%, 38%, 41% and 31% of the subjects, respectively. VGE incidence varied from 47-66%. No significant differences in DCS or VGE were found.
Under our test conditions, there was no difference between dynamic and isometric exercise in eliciting DCS. Exercise during exposure to the symptom-free altitude for 4 h produced a 40% incidence DCS.
自第二次世界大战以来，人们就知道在高海拔地区运动可增加减压病（DCS）的发病率。然而，关于高海拔地区特定运动类型影响的数据却很缺乏。本研究聚焦于无动作运动（等长运动、用力）与涉及动作的动态运动的相对风险。该研究还比较了上肢运动与下肢运动。
32名健康男性受试者在休息状态下暴露于29,500英尺（8992米）的高度4小时，或直至发生减压病，此时将他们带回地面。如果受试者在此暴露过程中患上减压病，后续数月他将按照相同程序暴露于较低海拔高度，直到该受试者在4小时暴露期间无症状。在这个无症状海拔高度，低至20,000英尺（6096米）时，受试者以低于最大耗氧量10%的强度分别在不同的暴露月份进行等长上肢运动、等长下肢运动、动态上肢运动和动态下肢运动。在每次暴露期间，每隔20分钟用惠普SONOS 1000超声成像系统监测心前区静脉气体栓子（VGE）。
动态上肢运动、动态下肢运动、等长上肢运动和等长下肢运动分别在50%、38%、41%和31%的受试者中诱发了减压病。VGE发生率在47%至66%之间。未发现减压病或VGE有显著差异。
在我们的测试条件下，动态运动和等长运动在诱发减压病方面没有差异。在无症状海拔高度暴露4小时期间进行运动，减压病的发病率为40%。
