Trent Stellingwerff

Nutrition is a key determinant of cycling performance, underpinning the ability to optimize on-bike performance, support training adaptation and recovery, and maintain rider health and well-being. While these goals are shared across disciplines, the diverse physiological demands and logistical constraints of different cycling disciplines present distinct nutritional challenges. In recognition of both the importance of nutrition and the diverse individual and discipline-specific demands of cycling, the Union Cycliste Internationale Sports Nutrition Project was established and led by a steering committee that synthesized the expertise of 54 researchers to identify key nutritional requirements for elite cycling and develop recommendations that account for both individual and discipline-specific needs. These insights were published within a series of 14 topic-specific reviews. In this position statement, we present the principal take-home messages from the overall project, organized into 10 overarching themes spanning performance preparation, in-competition fueling, recovery and adaptation, energy availability, physique management, protecting against illness and injury, technological support, the use of supplements and sports foods, and age- and sex-specific considerations. Cycling-specific considerations are used to develop targeted nutritional recommendations within each of these themes, and high-priority future research directions are identified.

Introduction: Energy availability (EA), defined as (energy intake [EI]—exercise energy expenditure [EEE])/fat free mass (FFM), has been studied in relation to athlete health and performance. We implemented a standardised audit protocol to assess the quality and characteristics of research that has calculated or manipulated EA in humans, and in particular, athletic populations. Methods: Using the Smith et al. 2020 standardised protocol, we searched the PubMed database in June 2024 and October 2025 to identify human studies that directly assessed or manipulated EA. Exclusion criteria for our audit were indirect measurements of EA (questionnaire or survey), measurement of energy balance only, studies of diseased populations or reports in languages other than English. The included publications were assessed across the following metrics: population, athletic calibre, menstrual classification, study design and EA methodology. Results: Of the 203 publications included in the audit, most included females (70%) or studied females alone (50%). High-performance athletes were well represented (45%; tiers 3–5) particularly among studies involving EA assessments. The audit system for evaluating the quality of menstrual status assessment found that 57% used techniques graded as ‘gold,’ ‘silver,’ and ‘bronze,’ yet a large proportion (43%) provided insufficient terminology or detail to classify female participants’ menstrual status (‘ungraded’). Most publications included naturally menstruating females (54%), while others included athletes with menstrual irregularities (28%) or those using hormonal contraceptives (18%). In studies observing EA ( n = 146), food records (82%) and metabolic equivalent scores (METs) (40%) were predominantly used to assess EI and EEE, respectively. Among intervention studies involving EA manipulations ( n = 57), most provided food to participants (77%) and determined EEE by physiologically derived methods (70%) such as indirect calorimetry or heart rate. Discussion/Conclusions: High performance female athletes (tiers 3–5) are well-represented in EA research compared with other areas of sports science/medicine research. Despite the well-known association between EA and menstrual dysfunction, many EA studies failed to use high-quality methodology to describe or account for menstrual characteristics of female participants. The quality of such research will improve with better standardisation and characterisation of menstrual cycles of female participants and with further investigation of differences in the causes of and responses to low EA (LEA) exposure in male athletes. A standardised calculation of EA and best practice protocols for its assessment may improve the quality of EA studies, however, a need to focus on intervention studies rather than assessment of EA in free-living athletes is necessary to better understand the effects of LEA exposure on health and performance.

Many emerging but non‐validated indicators and biomarker thresholds have been used in the Relative Energy Deficiency in Sport (REDs) literature. Accordingly, we (1) compared the outcomes of the 2023 International Olympic Committee REDs Clinical Assessment Tool‐version 2 (CAT2) (green, yellow, orange and red traffic light risk/severity assessment) with emerging REDs indicators, and (2) tested the utility of existing risk thresholds (clinical vs. subclinical biomarker cut‐offs) for primary and secondary REDs indicators. Female ( n = 143) and male ( n = 70) athletes (performance tier 3–5) were assessed with the CAT2 and emerging REDs indicators featuring a self‐report questionnaire, fasted blood analysis, resting blood pressure (BP) and heart rate (HR). Logistic regression was used to determine threshold cut‐offs for blood biomarkers at which there was an 80% probability of REDs. Red‐light athletes had significantly lower systolic BP ( p < 0.001), HR ( p = 0.009), white blood cell count (WBC; p = 0.018) and higher high‐density lipoprotein cholesterol ( p = 0.028) compared to green‐light. Elevated cortisol: insulin ratio ( p = 0.018), and reduced prolactin ( p < 0.001) and luteinizing hormone ( p < 0.05) concentrations were observed among higher‐risk (orange + red) versus lower‐risk (green + yellow) athletes. Males with total testosterone and triiodothyronine within the lowest quartile of reference range had an 80% probability of being classified as higher risk (orange + red) and history of BSI, respectively. For other outcomes at 80% probability, biomarkers were outside the clinical range. HR, systolic BP and WBC may be appropriate considerations for extreme (red‐light) REDs diagnosis. More research with larger numbers of orange/red light athletes is needed to confirm findings and elucidate athlete‐specific cut‐offs for subclinically low biomarkers.

Both sport-specific impact loading and Relative Energy Deficiency in Sport (REDs) are known to impact bone mineral density and bone stress injuries in athletes; however, the interactive effects are still emerging. The primary aim was to investigate the effects of sport-specific impact loading on bone mineral density and bone stress injuries and the influence this has on the International Olympic Committee's REDs Clinical Assessment Tool-Version 2 severity/risk assessment. Female (n = 143) and male (n = 70) athletes (performance tier 3-5) from 13 different sports were cross-sectionally assessed with the Clinical Assessment Tool-Version 2 (questionnaire, blood, dual-energy X-ray absorptiometry-derived bone mineral density assessment), and prospectively assessed for new bone stress injuries, and compared across low-, medium-, and high-impact loading sports. Spine and femoral neck Z-scores were significantly lower in low- and medium-impact versus high-impact sports (p < 0.01). The highest femoral neck Z-scores were in the high-impact group, with nearly all other low- and medium-impact groups being significantly (p < 0.016) lower regardless of REDs traffic-light status. The adjusted odds of future bone stress injuries were approximately three-fold higher in athletes with a recent bone stress injury (previous 2 years only; p = 0.16). Athletes in low-, medium- and high-impact sports with zero to low-risk REDs (green + yellow traffic-light) had femoral neck Z-scores of 0.4 ± 0.9, 0.5 ± 0.9 and 1.4 ± 1.0, respectively (p < 0.01). Sport-specific impact loading significantly influences bone mineral density independent of REDs risk/severity status. These findings indicate that practitioners should interpret bone mineral density results in the context of an athlete's specific sport background rather than relying solely on general population norms, enabling more accurate REDs risk assessment and targeted injury-prevention strategies.

Ultramarathon performance reflects a complex interplay of physiological, biomechanical, and psychosocial factors, yet data from multi-day events remain lim

Elite cyclists frequently train and compete in extreme environments, such as heat, and cold conditions that are becoming more common due to climate change. Altitude training, aimed at preparing athletes for high-altitude events, is widely employed to enhance subsequent sea-level performance. Similarly, heat training has proven to have a similar transfer effect, in addition to the essential acclimatization effects, relevant for performance in hot conditions. Exposure to these challenging environments increases physiological stress raising energy and carbohydrate oxidation rates, and affecting overall performance. This Union Cycliste Internationale (UCI) consensus on nutrition for cycling addresses the nutritional challenges associated with extreme environmental conditions and explores tailored nutrition and hydration strategies to mitigate their effects. The review examines how heat, cold, and altitude affect hydration, energy expenditure, and metabolism, with associated macro- and micronutrient considerations, in cyclists. It discusses practical strategies for managing fluid balance, carbohydrate intake, and micronutrient and electrolyte supplementation and the use of ergogenic aids in supporting adaptation to environmental stresses. This review provides evidence-based nutrition and fluid recommendations for optimizing cycling performance and fostering adaptation in extreme environments. It offers practical guidance on nutrition and hydration strategies before, during, and after training and competition, helping cyclists maintain peak performance while navigating the unique challenges posed by these conditions.

This article provides a synopsis of the 10 Questions/10 Experts session at the 2026 American College of Sports Medicine Annual Meeting, which examined whether sports nutrition guidelines are equally applicable from recreational to elite athletes. Each speaker considered the validity of a given common “myth” statement and provided an evidence-based opinion to support, bust, or qualify propositions addressing the following questions: (a) Are sports nutrition guidelines based primarily on studies of elite athletes, and are they too serious for recreational athletes? (b) Do recreational marathon runners need the same in-race carbohydrate recommendations as elite marathon runners? (c) Must recreational athletes consume 1.6 g·kg ⁻¹ ·day ⁻¹ of protein to benefit from exercise training? (d) Does nitrate supplementation benefit elite and recreational athletes equally? (e) Do recreational athletes need a structured fluid intake plan? (f) Is sodium bicarbonate loading relevant only to elite athletes? (g) Do recreational and elite athletes require more micronutrients than suggested by the Recommended Dietary Allowances? (h) Is eating after 8:00 p.m. detrimental to performance or recovery in recreational athletes? (i) Are recreational athletes at greater risk for suboptimal vitamin D status because indoor occupations reduce sunlight exposure? and (j) Should recreational athletes train with low carbohydrate availability to amplify adaptation? This article describes the content of each presentation, including the most important evidence, practical implications, and conclusions identified by the presenters.