運動時骨骼肌收縮會產生大量的代謝熱,當體內溫度(核溫)因代謝熱生成而開始上 升,汗腺便開始作用並分泌汗液,且皮膚血流(Skin blood flow)亦會大量增加,以調節體內溫 度(核溫)和皮膚溫度維持於一適當的範圍內,人體體內細胞構造與代謝途徑皆易因溫度變化 而受影響,所以體內溫度的調節是非常精密且重要的。本研究乃藉由連續測量9名健康無病之 非肥胖男性大學生漸增負荷運動中心跳率、血壓、皮膚溫、鼓室溫與皮膚血流,來探討漸增負 荷運動中心血管反應與熱調節反應的變化。研究結果顯示:於漸增負荷運動中(一)心血管反應: 為了維持肌群適當的血液灌流,而呈現出心跳率、收縮血壓與平均血壓會隨運動負荷的增加而 成正比上昇並隨運負荷的消失而遞減,然而舒張血壓於運動前後並無顯著的變化;(二)體溫調 節反應:身體核心溫度(耳鼓溫度)與體表溫度(皮膚溫度),除了運初期略降之外,亦隨運動負 荷(代謝熱生成)的增加而成正比線性上昇,但當運動負荷大於77%VO□max時,其關係會改呈 一直線關係而迅速上昇,並於衰竭時達到最高溫,並運動自始至終核溫均高於膚溫,而膚溫之 變化量大於核溫;(三)皮膚血流反應:皮膚血流量(上肢與下肢)會隨運動負荷的增加而成正比 上昇,然而於運動前期(約44.4%V0□max),下肢皮膚血流量之增幅大於上肢皮膚血流量而於 運動中期(66.6%V0□max)至運動末期前刻(88.9%V0□max)則上肢皮膚血流量之增幅反而大於 下肢皮膚血流量,並於運動衰竭前刻也即在最大運動之88.9%時,因壓力調節感覺器 (Baroreceptor)反射性防衛約制作用,兩者即同時急速下降,爾後即隨運動之終止而逐減,其 降幅則下肢皮膚血流量大於上肢皮膚血流量。

　　　　　During exercise, the working muscle will produce large amount of metabolic heat production, the sweat glands are activated, and skin blood flow is augmented as a function of internal and skin temperature, to maintain human body's internal and skin temperature in a moderate range. Since limited data are available from simultaneous measurements of certain cardiovascular and thermoregulation variables during incremental exercise, we secured such data by simultaneous measurements heart rate, blood pressure and skin blood flow while exercised, to examined these physiological adjustments during heat production by exercise. The present result showed that during incremental exercise: (1) in order to maintain moderate muscle perfusion, the heart rate, systolic blood pressure and mean blood pressure was increased linearly with the work load; (2) the internal and skin temperature was increased linearly with the work load (metabolic heat production), but up to 77% VO □max, both temperature increased more rapidly and reach the highest when exhaustion; (3) skin blood flow (forearm and thigh) was increased linearly with the metabolic heat production, but at the heaviest work load, the skin blood flow was clearly attenuated, suggested that cutaneous vasoconstriction occurs during severe exercise.