Abstract
Background/Objectives: Despite increasing awareness of best sports nutrition practices, discrepancies persist between knowledge and behaviour amongst female endurance athletes. Methods: To understand this discrepancy study investigated dietary practices, macronutrient intakes, and influ-encing factors using a multi-method approach. Seventy-two female endurance athletes (42 ± 9 y) completed four-day weighed food diaries, and a subset of twenty athletes (40 ± 10 y) then participated in semi-structured interviews. Quantitative analysis revealed that athletes met the lower end of carbohydrate (CHO) guidelines on rest days (3.0 g·kg−1), but intake fell short on training days, with deficits increasing as training volume rose (moderate: −1.4 g·kg−1, high: −3.5 g·kg−1, very high: −5.5 g·kg−1). Despite awareness of CHO’s role in performance, athletes unintentionally underfuelled, leading to a cumu-lative energy deficit. Energy intake increased by 473 kcal·day−1 per 1000 kcal·day−1 of exercise energy expenditure. In contrast, protein intake was prioritised, with mean in-takes of 1.7 ± 0.7 g·kg−1·day−1 aligning with recommendations. Results: Qualitative findings iden-tified barriers to CHO intake, including time constraints, diet culture influences and body image concerns. Social and environmental factors, such as household environments and professional nutrition guidance, played a critical role in behaviours. Conclusions: These findings highlight the need for practical, evidence-based nutrition interventions to support fe-male endurance athletes. Personalised education addressing CHO requirements, the psychology/emotions around nutrition, and the influence of social environments may bridge the gap between knowledge and practice, optimising both performance and long-term health outcomes.