3 Thermoregulation at Rest and during Exercise in Healthy Older Adults
3 Thermoregulation at Rest and during Exercise in Healthy Older Adults
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3 健康老年人休息和运动时的体温调节
DOI：
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发表时间：
1997
影响因子：
5.7
通讯作者：
W. Kenney
中科院分区：
文献类型：
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作者：
W. Kenney
流行病学证据表明，体温过高和过低导致老年男女死亡率增加，但这不应被解释为老龄化本身导致对极端环境的不容忍。相对较少的研究试图从伴随因素（如最大摄氧量降低、习惯性活动水平降低、身体成分改变等）中描述实足年龄的影响。在确定热环境中对休息和运动的体温调节反应。当慢性疾病和久坐不动的生活方式的影响保持在最低限度时，耐热性似乎受到年龄的影响最小。在预测运动时的体温方面，VO2max比年龄更重要，尽管与散热相关的一些生理机制（特别是皮肤血流的控制和心输出量的分布）与实际年龄密切相关。脱水的影响可能会在老年人中被放大，而再水合作用可能会受到与年龄相关的口渴敏感性和肾功能差异的影响。各种干预措施在改善老年人体温调节反应方面的疗效（例如，有氧训练和热适应）尚未得到充分研究。老年男性和女性能够适应炎热的条件，但随着年龄的增长，适应的生理变化的时间过程可能不同。另一个有希望的干预措施是绝经后妇女的激素替代疗法，它会对体温调节和体液控制产生积极的影响。激素替代疗法对运动和环境应激期间体温调节的慢性影响尚不清楚。在休息条件下对冷暴露的耐受性可能不太依赖于年龄和有氧健身，而不是身体成分。对老年人和年轻人在寒冷环境中锻炼的研究完全缺乏，包括定期体育活动对寒冷应激生理反应的可能预防作用的重要研究。
Epidemiological evidence of increased mortality among older men and women resulting from hyper- and hypothermia should not be interpreted as implying that aging per se confers an intolerance to environmental extremes. Relatively few studies have attempted to delineate the effects of chronological age from concomitant factors (such as decreases in VO2max, lowered habitual activity levels, alterations in body composition, etc.) in determining thermoregulatory responses to rest and exercise in hot environments. When the effects of chronic diseases and sedentary life-style are kept to a minimum, heat tolerance appears to be minimally compromised by age. VO2max is more important than age in predicting body temperature during exertion, even though some of the physiological mechanisms associated with heat dissipation (especially control of skin blood flow and distribution of cardiac output) are closely associated with chronological age. Dehydration effects may be magnified in older individuals, and rehydration may be compromised by age-related differences in thirst sensitivity and renal function. The efficacy of various interventions in improving thermoregulatory responses of older individuals (e.g., aerobic training and heat acclimation) has not been studied adequately. Older men and women are capable of acclimating to hot conditions, but the time course of physiological changes underlying acclimation with age may be different. Another intervention that holds promise is hormone replacement therapy in postmenopausal women, which acutely affects temperature regulation and control of body fluids in a positive direction. The chronic effects of hormone replacement therapy on thermoregulation during exercise and environmental stresses are not known. Tolerance to cold exposure under resting conditions may be less dependent on age and aerobic fitness than on body composition. Studies of older and younger subjects exercising in cold environments are lacking altogether, including important studies into the possible preventive effects of regular physical activity on physiological responses to cold stress.