This study sought to investigate the effect of cold ambient temperature on subcutaneous abdominal adipose tissue (SCAAT) lipolysis and blood flow during steady-state endurance exercise in endurance-trained cyclists. Ten males (age: 23 ± 3 years; peak oxygen consumption: 60.60 ± 4.84 ml·kg⁻¹·min⁻¹; body fat: 18.4% ± 3.5%) participated in baseline lactate threshold (LT) and peak oxygen consumption testing, two familiarization trials, and two experimental trials. Experimental trials consisted of cycling in COLD (3 °C; 42% relative humidity) and neutral (NEU; 19 °C; 39% relative humidity) temperatures. Exercise consisted of 25 min cycling at 70% LT and 25 min at 90% LT. In situ SCAAT lipolysis and blood flow were measured via microdialysis. Heart rate, core temperature, carbohydrate and fat oxidation, blood glucose, and blood lactate were also measured. Heart rate, core temperature, oxygen consumption, and blood lactate increased with exercise but were not different between COLD and NEU. SCAAT blood flow did not change from rest to exercise or between COLD and NEU. Interstitial glycerol increased during exercise (p < .001) with no difference between COLD and NEU. Fat oxidation increased (p < .001) at the onset of exercise and remained elevated thereafter with no difference between COLD and NEU. Carbohydrate oxidation increased with increasing exercise intensity and was greater at 70% LT in COLD compared to NEU (p = .030). No differences were observed between conditions for any other variable. Cycling exercise increased SCAAT lipolysis but not blood flow. Ambient temperature did not alter SCAAT metabolism, SCAAT blood flow, or fat oxidation in well-trained cyclists, though cold exposure increased whole-body carbohydrate oxidation at lower exercise intensities.

本研究旨在探讨寒冷环境温度对经过耐力训练的自行车运动员进行稳态耐力运动期间皮下腹部脂肪组织 (SCAAT) 脂肪分解和血流的影响。十名男性（年龄：23​​±3岁；峰值耗氧量：60.60±4.84ml·kg ⁻¹ ·min ⁻¹；体脂：18.4%±3.5%）参加基线乳酸阈值（LT）和峰值耗氧量测试，两次熟悉试验和两次实验试验。实验包括在冷（3°C；42% 相对湿度）和中性（NEU；19°C；39% 相对湿度）温度下循环。锻炼包括 25 分钟 70% LT 骑行和 25 分钟 90% LT 骑行。通过微透析测量原位 SCAAT 脂肪分解和血流量。还测量了心率、核心温度、碳水化合物和脂肪氧化、血糖和血乳酸。心率、核心温度、耗氧量和血乳酸随着运动而增加，但在 COLD 和 NEU 之间没有差异。 SCAAT 血流量从休息到运动或在 COLD 和 NEU 之间没有变化。运动期间间质甘油增加 ( p  < .001)，COLD 和 NEU 之间没有差异。脂肪氧化 在运动开始时增加 ( p < .001)，此后保持升高状态，COLD 和 NEU 之间没有差异。碳水化合物氧化随着运动强度的增加而增加，与 NEU 相比，COLD 中 70% LT 时的碳水化合物氧化程度更高 ( p  = .030)。任何其他变量的条件之间没有观察到差异。骑自行车运动会增加 SCAAT 脂肪分解，但不会增加血流量。环境温度不会改变训练有素的自行车运动员的 SCAAT 代谢、SCAAT 血流量或脂肪氧化，但在较低运动强度下，寒冷暴露会增加全身碳水化合物氧化。