Nutritional Interventions and Acupuncture-Based Strategies for Exercise-Induced Fatigue and Recovery: Mechanisms and...

Exercise-induced fatigue (EIF) refers to a reduced capacity to sustain a specified level or intensity of physical activity and is generally regarded as a physiological warning signal following excessive exercise rather than a pathological state. It involves peripheral disturbances related to energy depletion, metabolite accumulation, oxidative stress, inflammation, and mitochondrial dysfunction, together with central changes involving neuroendocrine networks and the gut-brain axis. In this review, we synthesize evidence from nutritional interventions and acupuncture-based strategies and outline a conceptual mechanistic framework relevant to EIF management. Nutritional approaches include macronutrient manipulation, vitamins, plant-derived polyphenols and polysaccharides, traditional herbal extracts, probiotics, and fermented products. Acupuncture, electroacupuncture (EA), and transcutaneous electrical acupoint stimulation (TEAS) have been associated with regulation of autonomic function and hypothalamic-pituitary-adrenal axis activity, modulation of pain and affective circuits, and changes in skeletal muscle perfusion, mitochondrial function, and antioxidant and anti-inflammatory signaling. We highlight partially overlapping biological targets, including the AMPK/PGC-1α axis, Nrf2 and NF-κB signaling pathways, and cytokine networks, and propose a conceptual model in which nutritional interventions are primarily linked to substrate availability and redox support, whereas acupuncture-based strategies are primarily linked to neuroendocrine and inflammatory regulation, with both being associated with mitochondrial function and recovery-related processes. Current evidence is limited by protocol heterogeneity, small sample sizes, sparse mechanistic biomarker profiling, and a predominance of animal studies. We therefore outline priorities for multi-arm randomized controlled trials, standardization of EA/TEAS parameters, multi-omics integration, and the development of individualized prescription models. Shared mechanistic features between nutritional and acupuncture-based interventions may inform future hypothesis-driven studies of EIF; however, whether combined use provides additive or synergistic clinical benefit remains unproven and requires rigorous validation.