NUTRITIONAL INTERVENTIONS TO AUGMENT HIGH-THROUPUT INTERVAL TRAINING DURING PHYSIOLOGICAL AND PERFORMANCE ADAPTATIONS

High-intensity interval training (HIIT) and other forms of high-throughput interval training are increasingly recognized as efficient exercise strategies for improving cardiovascular fitness, metabolic health, muscular performance, and exercise capacity within relatively short training periods. However, the physiological adaptations induced by repeated high-intensity exercise are strongly influenced by nutritional status, energy availability, substrate utilization, and post-exercise recovery. Nutritional interventions may therefore provide an important complementary approach to maximize the physiological and performance benefits of interval training. The integration of targeted nutritional strategies—including adequate carbohydrate availability, high-quality protein and essential amino acids, hydration and electrolyte replacement, and selected evidence-based nutraceuticals—may enhance exercise tolerance, optimize energy metabolism, support muscle protein synthesis, reduce excessive fatigue, and accelerate recovery between training sessions. Specific interventions such as creatine, dietary nitrate, omega-3 fatty acids, vitamin D in deficient individuals, and selected polyphenol-rich foods may further influence pathways involved in mitochondrial function, muscle adaptation, inflammation, oxidative stress, and neuromuscular performance. However, the response to nutritional supplementation is highly individualized and may depend on training status, exercise intensity, baseline nutritional status, timing, dose, and the type of adaptation being targeted. The rationale for nutritional interventions during interval training is therefore based on the concept that optimal nutrition can augment, rather than replace, the adaptive stimulus provided by exercise. A well-designed nutritional strategy may help maintain training quality, increase the capacity to perform repeated highintensity bouts, and facilitate recovery, thereby potentially enhancing long-term cardiovascular, metabolic, muscular, and performance adaptations. Nevertheless, excessive or inappropriate supplementation, particularly high-dose antioxidant use, may not necessarily improve adaptation and could potentially interfere with beneficial exercise-induced signalling pathways. This topic highlights the need for an integrated, individualized approach combining exercise prescription, nutritional optimization, recovery, and evidence-based nutraceutical use. Further controlled research is warranted to identify which nutritional interventions, when provided to which individuals and at what stage of training, most effectively enhance physiological adaptations and performance outcomes associated with high-intensity interval training.