FATTY-ACID KINETIC RESPONSES TO RUNNING ABOVE OR BELOW LACTATE THRESHOLD
FATTY-ACID KINETIC RESPONSES TO RUNNING ABOVE OR BELOW LACTATE THRESHOLD
复制标题
DOI：
10.1152/jappl.1995.79.2.439
复制
发表时间：
1995-08-01
影响因子：
3.3
通讯作者：
JENSEN, MD
中科院分区：
文献类型：
--
作者：
KANALEY, JA;MOTTRAM, CD;JENSEN, MD
在高于乳酸阈（LT）的跑步运动中，游离脂肪酸（FFA）动员是否能满足脂肪酸氧化的能量需求尚不清楚。本研究旨在确定与LT以下相比，跑步运动期间FFA可用性是否降低，并评估耐力训练水平是否影响FFA动员。12名马拉松运动员和12名中等训练的运动员在高于或低于其个人LT的工作负荷下跑步。在基线、整个运动过程和恢复期测量脂肪酸氧化（间接热量测定法）和FFA释放（[1-C-14]棕榈酸酯）。两组在高于或低于LT水平的运动过程中，血浆FFA出现率均增加，但低于LT水平组（马拉松，23 +/- 2 mmol;中度，21 +/- 2 mmol）运动30 min的总FFA可用性高于高于LT水平组（分别为18 +/- 3和13 +/- 3 mmol）（P < 0.01）。无论训练组还是运动组，总脂肪酸氧化（间接量热法）大大超过循环FFA可用性（P < 0.01）。未发现脂肪酸氧化的统计学显著运动强度或训练差异（高于LT：马拉松，71 +/- 12，中度，64 +/- 17 mmol/30 min;低于LT：马拉松，91 +/- 12，中度，60 +/- 5 mmol/30 min）。总之，在高于或低于LT的运动期间，循环FFA不能满足氧化需求，必须利用肌内甘油三酯储备。与中等耐力训练相比，进一步的马拉松训练并不能增强运动过程中有效的脂肪组织脂解。
During running exercise above the lactate threshold (LT), it is unknown whether free fatty acid (FFA) mobilization can meet the energy demands for fatty acid oxidation. This study was performed to determine whether FFA availability is reduced during running exercise above compared with below the LT and to assess whether the level of endurance training influences FFA mobilization. Twelve marathon runners and 12 moderately trained runners ran at a workload that was either above or below their individual LT. Fatty acid oxidation (indirect calorimetry) and FFA release ([1-C-14]palmitate) were measured at baseline, throughout exercise, and at recovery. The plasma FFA rate of appearance increased during exercise in both groups, running above or below the LT, but the total FFA availability for 30 min of exercise was greater (P < 0.01) in the below LT group (marathon, 23 +/- 2 mmol; moderate, 21 +/- 2 mmol) than in the above LT group (18 +/- 3 and 13 +/- 3 mmol, respectively). Total fatty acid oxidation (indirect calorimetry) greatly exceeded circulating FFA availability, regardless of training or exercise group (P < 0.01). No statistically significant exercise intensity or training differences in fatty acid oxidation were found (above LT: marathon, 71 +/- 12, moderate, 64 +/- 17 mmol/30 min; below LT: marathon 91 +/- 12, moderate, 60 +/- 5 mmol/30 min). In conclusion, during exercise above or below LT, circulating FFA cannot meet the oxidative needs and intramuscular triglyceride stores must be utilized. Further marathon training does not enhance effective adipose tissue lipolysis during exercise compared with moderate endurance training.