Bradwell Arthur R, Ashdown Kimberley, Rue Carla, Delamere John, Thomas Owen D, Lucas Samuel J E, Wright Alex D, Harris Stephen J, Myers Stephen D
Institute of Clinical Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, UK.
Department of Sport and Exercise Sciences, University of Chichester, Chichester, UK.
BMJ Open Sport Exerc Med. 2018 Jan 23;4(1):e000302. doi: 10.1136/bmjsem-2017-000302. eCollection 2018.
To assess whether acetazolamide (Az), used prophylactically for acute mountain sickness (AMS), alters exercise capacity at high altitude.
Az (500 mg daily) or placebo was administered to 20 healthy adults (aged 36±20 years, range 21-77), who were paired for age, sex, AMS susceptibility and weight, in a double-blind, randomised manner. Participants ascended over 5 days to 4559 m, then exercised to exhaustion on a bicycle ergometer, while recording breath-by-breath gas measurements. Comparisons between groups and matched pairs were done via Mann-Whitney U and Pearson's χ tests, respectively.
Comparing paired individuals at altitude, those on Az had greater reductions in maximum power output (P) as a percentage of sea-level values (65±14.1 vs 76.6±7.4 (placebo); P=0.007), lower VO (20.7±5.2 vs 24.6±5.1 mL/kg/min; P<0.01), smaller changes from rest to P for VO (9.8±6.2 vs 13.8±4.9 mL/kg/min; P=0.04) and lower heart rate at P (154±25 vs 167±16, P<0.01) compared with their placebo-treated partners. Correlational analysis (Pearson's) indicated that with increasing age P (=-0.83: P<0.005) and heart rate at P (=-0.71, P=0.01) reduced more in those taking Az.
Maximum exercise performance at altitude was reduced more in subjects taking Az compared with placebo, particularly in older individuals. The age-related effect may reflect higher tissue concentrations of Az due to reduced renal excretion. Future studies should explore the effectiveness of smaller Az doses (eg, 250 mg daily or less) in older individuals to optimise the altitude-Az-exercise relationships.
评估预防性使用乙酰唑胺（Az）治疗急性高原病（AMS）是否会改变高原地区的运动能力。
采用双盲、随机方式，将20名健康成年人（年龄36±20岁，范围21 - 77岁）按年龄、性别、AMS易感性和体重配对，分别给予Az（每日500毫克）或安慰剂。参与者在5天内升至4559米，然后在自行车测力计上运动至力竭，同时记录逐次呼吸的气体测量值。组间和配对个体的比较分别通过曼 - 惠特尼U检验和皮尔逊χ检验进行。
在高原地区比较配对个体时，服用Az的个体与服用安慰剂的配对个体相比，最大功率输出（P）相对于海平面值的降低幅度更大（65±14.1对76.6±7.4（安慰剂）；P = 0.007），最大摄氧量（VO）更低（20.7±5.2对24.6±5.1毫升/千克/分钟；P < 0.01），从休息到P时VO的变化更小（9.8±6.2对13.8±4.9毫升/千克/分钟；P = 0.04），且在P时心率更低（154±25对167±16，P < 0.01）。相关性分析（皮尔逊）表明，随着年龄增长，服用Az的个体中P（r = - 0.83：P < 0.005）和P时的心率（r = - 0.71，P = 0.01）下降得更多。
与安慰剂相比，服用Az的受试者在高原地区的最大运动表现下降得更多，尤其是在老年人中。与年龄相关的影响可能反映了由于肾排泄减少导致Az在组织中的浓度更高。未来的研究应探索较小剂量的Az（例如，每日250毫克或更低）对老年人的有效性，以优化高原 - Az - 运动之间的关系。
