Endurance training in fasted conditions (FAST) induces favorable skeletal muscle metabolic adaptations compared with carbohydrate feeding (CHO), manifesting in improved exercise performance over time. Sprint interval training (SIT) is a potent metabolic stimulus, however nutritional strategies to optimize adaptations to SIT are poorly characterized. Here we investigated the efficacy of FAST versus CHO SIT (4–6 × 30-s Wingate sprints interspersed with 4-min rest) on muscle metabolic, serum metabolome and exercise performance adaptations in a double-blind parallel group design in recreationally active males. Following acute SIT, we observed exercise-induced increases in pan-acetylation and several genes associated with mitochondrial biogenesis, fatty acid oxidation, and NAD⁺-biosynthesis, along with favorable regulation of PDK4 (p = .004), NAMPT (p = .0013), and NNMT (p = .001) in FAST. Following 3 weeks of SIT, NRF2 (p = .029) was favorably regulated in FAST, with augmented pan-acetylation in CHO but not FAST (p = .033). SIT induced increases in maximal citrate synthase activity were evident with no effect of nutrition, while 3-hydroxyacyl-CoA dehydrogenase activity did not change. Despite no difference in the overall serum metabolome, training-induced changes in C3:1 (p = .013) and C4:1 (p = .010) which increased in FAST, and C16:1 (p = .046) and glutamine (p = .021) which increased in CHO, were different between groups. Training-induced increases in anaerobic (p = .898) and aerobic power (p = .249) were not influenced by nutrition. These findings suggest some beneficial muscle metabolic adaptations are evident in FAST versus CHO SIT following acute exercise and 3 weeks of SIT. However, this stimulus did not manifest in differential exercise performance adaptations.

与碳水化合物喂养 (CHO) 相比，禁食条件下的耐力训练 (FAST) 可诱导有利的骨骼肌代谢适应，随着时间的推移表现为运动表现的改善。冲刺间歇训练 (SIT) 是一种有效的代谢刺激，但优化适应 SIT 的营养策略的特征却很差。在这里，我们研究了 FAST 与 CHO SIT（4-6 × 30-s Wingate 冲刺穿插 4 分钟休息）在双盲平行组设计中对休闲活跃男性的肌肉代谢、血清代谢组和运动表现适应的功效。在急性 SIT 之后，我们观察到运动诱导的泛乙酰化增加以及与线粒体生物发生、脂肪酸氧化和 NAD ^{+相关的几个基因}-生物合成，以及 FAST 中PDK4 ( p  = .004)、NAMPT ( p  = .0013) 和NNMT ( p = .001) 的有利调节。在 SIT 3 周后，NRF2 ( p  = .029) 在 FAST 中受到有利调节，在 CHO 中泛乙酰化增强，但在 FAST 中则不然 ( p  = .033)。SIT 诱导的最大柠檬酸合酶活性增加很明显，而营养没有影响，而 3-羟基酰基辅酶 A 脱氢酶活性没有改变。尽管总体血清代谢组没有差异，但训练引起的 C3:1 ( p  = .013) 和 C4:1 ( p = .010) 在 FAST 中增加，而 在 CHO 中增加的C16:1 ( p  = .046) 和谷氨酰胺 ( p = .021) 在组间是不同的。训练引起的无氧能力 ( p  = .898) 和有氧能力 ( p  = .249) 的增加不受营养的影响。这些发现表明，在急性运动和 3 周的 SIT 后，FAST 与 CHO SIT 相比，一些有益的肌肉代谢适应是明显的。然而，这种刺激并没有体现在不同的运动表现适应中。