Harris A, Malinovsky V, Martin B
Department of Ophthalmology, Indiana University School of Medicine, Indianapolis 46202-5175.
Invest Ophthalmol Vis Sci. 1994 Oct;35(11):3852-7.
To understand those factors that determine the decrease in intraocular pressure (IOP) that occurs during acute dynamic exercise.
Three aspects of the exercise-IOP relationship were studied. These included graded exercise, with and without CO2 addition for isocapnia; comparison of the IOP response of trained and sedentary subjects to a fixed external work load; and exercise after ocular beta-adrenoceptor blockade. Graded exercise consisted of 7 minutes each at 30 and 90 watts on a cycle ergometer, then progressive work to exhaustion. Trained and sedentary subjects were defined on the basis of the blood lactate response to fixed external work (10 minutes at 90 watts). Selective beta 1-adrenoceptor blockade (betaxolol) and nonselective beta-adrenoceptor blockade (levobunolol) were superimposed on graded exercise. Intraocular pressure was measured using applanation tonometry.
Graded exercise: Intraocular pressure decreased in proportion to exercise intensity. Hypocapnia developed in the last minutes of exhausting work, but preventing hypocapnia with CO2 addition failed to lessen the decrease in IOP. Response to fixed external work load: Intraocular pressure decreased significantly more in sedentary than in trained subjects; this decline was correlated with elevations in blood lactate but not with changes in metabolic rate or plasma osmolarity. Selective and nonselective beta-adrenoceptor blockade: Both drugs lowered IOP at baseline and throughout graded exercise; the drugs and exercise had apparently additive ocular hypotensive effects.
Acute dynamic exercise lowers IOP in a graded fashion proportional to relative, not absolute, work load. The IOP decline is correlated with blood lactate but not with PCO2 or plasma osmolarity changes, and exercise potentiates the ocular hypotensive effects of beta-adrenoceptor blockade.
了解那些决定急性动态运动期间眼压（IOP）下降的因素。
研究了运动与眼压关系的三个方面。这些包括分级运动，在等碳酸条件下添加和不添加二氧化碳；比较训练有素的受试者和久坐不动的受试者对固定外部工作负荷的眼压反应；以及眼部β-肾上腺素能受体阻断后的运动。分级运动包括在自行车测力计上以30瓦和90瓦各运动7分钟，然后逐渐增加负荷直至疲劳。根据对固定外部工作（90瓦运动10分钟）的血乳酸反应来定义训练有素的受试者和久坐不动的受试者。在分级运动中叠加选择性β1-肾上腺素能受体阻断（倍他洛尔）和非选择性β-肾上腺素能受体阻断（左布诺洛尔）。使用压平眼压计测量眼压。
分级运动：眼压随运动强度成比例下降。在疲劳运动的最后几分钟出现低碳酸血症，但添加二氧化碳以防止低碳酸血症并不能减轻眼压的下降。对固定外部工作负荷的反应：久坐不动的受试者眼压下降明显多于训练有素的受试者；这种下降与血乳酸升高相关，但与代谢率或血浆渗透压的变化无关。选择性和非选择性β-肾上腺素能受体阻断：两种药物在基线时和整个分级运动过程中均降低眼压；药物和运动显然具有相加的降眼压作用。
急性动态运动以分级方式降低眼压，与相对而非绝对工作负荷成比例。眼压下降与血乳酸相关，但与PCO2或血浆渗透压变化无关，并且运动增强了β-肾上腺素能受体阻断的降眼压作用。
