The Journal of Sports Medicine and Physical Fitness 2020 Dec 03

DOI: 10.23736/S0022-4707.20.11792-4

Copyright © 2020 EDIZIONI MINERVA MEDICA

lingua: Inglese

Vitamin A intake is related to stress fracture occurrence in male collegiate long-distance runners

Mami TORAISHI ^{1, 4} ✉, Kazuhiro UENISHI ², Jun IWAMOTO ³, Toshiro OTANI ¹

¹ Graduate School of Health Management, Keio University, Kanagawa, Japan; ² Laboratory of Physiological Nutrition, Kagawa Nutrition University, Saitama, Japan; ³ Bone and Joint Disease Center, Keiyu Orthopaedic Hospital, Gunma, Japan; ⁴ Teikyo University Institute of Sports Science & Medicine, Tokyo, Japan

BACKGROUND: Nutrient intake has an essential role in bone disorder prevention among long-distance runners. However, the influence of vitamin A intake on the risk of stress fractures remains unknown. This prospective study aimed to investigate the association between vitamin A intake, and stress fracture occurrence in male collegiate long-distance runners.
METHODS: Forty-one male long-distance runners were recruited from a top-class longdistance college running team whose complete survey data on bone mass, anthropometric measurements, blood and urine tests, food intake frequency, history of competing in longdistance races, and monthly running distance during 2009-2010 were available. The influence of factors related to stress fractures, including vitamin A intake, at baseline and the occurrence of stress fractures during the 1-year period were investigated.
RESULTS: Four athletes experienced stress fractures during the study period (stress fracture group) and had significantly higher vitamin A, calcium, and iron intake at baseline compared with that in the nonstress fracture group. In the stress fracture group, the mean daily vitamin A intake was 2,792 μg of retinol activity equivalents (RAE), which was higher than the upper intake limit for males aged 18-25 years in the Japanese Dietary Standard. Logistic regression analyses showed that only vitamin A intake independently contributed to stress fracture occurrence. The odds ratio of developing stress fractures with a 100-μg RAE increase in vitamin A intake was 1.22.
CONCLUSIONS: A result of the present study suggested that vitamin A intake was associated with stress fracture occurrence in male collegiate long-distance runners.

KEY WORDS: Stress fractures; Long-distance runners; Nutrients; Vitamin A; Bone mineral density