Availability of glycogen and plasma FFA for substrate utilization in leg muscle of man during exercise
Availability of glycogen and plasma FFA for substrate utilization in leg muscle of man during exercise
复制标题
运动期间人体腿部肌肉底物利用的糖原和血浆 FFA 的可用性
DOI：
--
复制
发表时间：
1981
期刊：
影响因子：
--
通讯作者：
B. Saltin
中科院分区：
文献类型：
--
作者：
P. D. Gollnick;B. Pernow;B. Essén;E. Jansson;B. Saltin
摘要六名男子进行两条腿的自行车测力计运动负荷要求2-4和3-4升O2 min-1（62和84%的Vo 2 max）为20分钟，或耗尽两次1小时之间的休息。一个初始的糖原差异28 mmol葡萄糖单位kg-1的大腿肌肉之间的两条腿产生的单腿运动在前一天，然后由低碳水化合物饮食的消费。在1小时休息期间，给予烟酸（NA）以抑制脂解。NA给药后，全身Fo 2未发生变化。每一条腿所做的功，用作用在踏板上的力来表示，是相等的。RQ表明在低糖原的腿中脂肪氧化更大。肌糖原为15和10 mmol kg-1，在正常和低糖原的腿在第一次运动结束时和3-8 mmol kg-1，在两条腿在耗尽。低糖原腿从血液中提取乳酸，而正常腿释放乳酸，并且低糖原腿从血液中摄取的葡萄糖更多。低糖原和控制腿之间的这些差异并没有持续NA条件时，肌肉糖原含量是相等的双腿。此外，对照和NA条件下的腿部葡萄糖摄取与糖原空肌纤维的百分比正相关，与葡萄糖-6-P 〇 4浓度负相关。因此，肌肉的局部糖原储备的大小影响血液基质的摄取和使用，以及在中等强度到高强度运动期间确定耐力能力。
Summary. Six men performed two-legged cycle ergometer exercise at loads demanding 2–4 and 3–4 litres O2 min-1 (62 and 84% of Vo2 max) for 20 min each or to exhaustion twice with 1 h rest between. An initial glycogen difference of 28 mmol glucose units kg-1 of thigh muscle between the two legs was produced by one-legged exercise on a previous day followed by the consumption of a low carbohydrate diet. During the 1 h rest nicotinic acid (NA) was administered to inhibit lipolysis. Total body Fo2 was unchanged by the NA administration. Work done by each leg, indicated by force on the pedals, was equal. RQ indicated a larger oxidation of fat in the leg with low glycogen. Muscle glycogen was 15 and 10 mmol kg-1 in the normal and low glycogen leg at the end of the first exercise bouts and 3–8 mmol kg-1 in both legs at exhaustion. The low glycogen leg extracted lactate from the blood whereas the normal leg released lactate and the uptake of glucose from the blood was greater by the low glycogen leg. These differences between the low glycogen and control legs did not persist during the NA condition when muscle glycogen content was equal in both legs. Further, the leg glucose uptake in the control and the NA conditions was positively related to the percentage of glycogen-empty muscle fibres and inversely to the glucose-6-P04 concentration. Thus the magnitude of the local glycogen stores of muscle influences the uptake and use of blood-borne substrates as well as determining endurance capacity during moderate to high intensity exercise.