Triathlon-specific evidence on bone health is small, cross-sectional and heterogeneous, showing no uniform bone mineral density deficit, and does not support universal imaging, biomarker testing, or supplementation, so individualized assessment is preferable.
The triathlon-specific evidence base on bone health is limited in size and quality.
No uniform bone mineral density deficit was found in triathletes.
A four-year cohort of elite short-course triathletes showed a substantial burden of bone stress injury (BSI), with a higher rate in females.
Evidence on low energy availability (LEA), the Female Athlete Triad and Relative Energy Deficiency in Sport (REDs) in triathletes relies on weak methodologies and is sparse for males.
Biomarkers, areal bone mineral density, structural imaging, risk screens, and BSI are not interchangeable measures.
The evidence does not support universal imaging, biomarker testing, or supplementation in triathletes; individualized assessment is preferable.
Future research should be prospective, preregistered, and inclusive of both sexes and a range of ages, with aligned exposure and outcome measures.
This review looked at what is known about bone health in triathletes, who combine swimming and cycling (both low-impact for bones) with running (high-impact) and often have high energy demands. The authors examined 25 reports covering roughly 20-22 groups of athletes. Most studies were small, took a single snapshot in time, and differed a lot from one another. The review found no consistent pattern of low bone density in triathletes. Results varied with the part of the body measured, sex, age, body size, competitive level, race distance, and the sport's discipline. One four-year study of 50 elite short-course triathletes found many bone stress injuries, more often in women, but it came from a single program, so it may not apply to all triathletes. Evidence on low energy availability (not eating enough to support training and body functions) came mostly from questionnaires, diet records, and case reports, and there was little on men or on ways to prevent or treat problems. This research suggests that blanket approaches, such as scanning, blood-testing, or supplementing every triathlete, are not supported by current evidence, and that assessing athletes individually may be more appropriate. The authors call for better, larger, prospective studies that include men and women of different ages and that track training, energy intake, bone measurements, and confirmed injuries over time.
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Upload Your LabsLin P, Su O, Wu W, Lee R, Yao T, Yeh K. (2026). Bone Health in Triathletes: Skeletal Loading, Low Energy Availability, and Bone Stress Injury-A Critical Narrative Review.. Medicina (Kaunas, Lithuania). https://doi.org/10.3390/medicina62101894