title: Influence of food restriction combined with voluntary running on bone morphology and strength in male rats.
abstract: Athletes, in particular endurance athletes and dancers, are chronically exposed to a state of low energy availability due to insufficient dietary energy intake and massive exercise energy expenditure. Low energy availability sometimes causes bone fragility, thereby increasing the risk of bone disorders. Although the decrease in energy availability shows no sexual dimorphism, epidemiological studies have reported that bone disorders are less frequent in male athletes than in female athletes. We hypothesized that bone tissue was not affected by low energy availability in males. The purpose of this study was to examine the influence of food restriction combined with voluntary running training on bone morphology and strength in adult male rats. Fourteen-week-old male Sprague-Dawley rats were divided randomly into four groups: control (C) group, food restriction (R) group, exercise (Ex) group, and food restriction plus exercise (REx) group. For the R and REx groups, 30 % food restriction was carried out in comparison with the C group. Bone strength, bone mineral density (BMD), bone architecture, and bone turnover rate were measured after a 13-week experimental period. Bone strength was not significantly lower in the REx group compared with the C group. BMD and trabecular bone volume showed no difference among groups. These findings indicate that bone morphology and strength were little affected by food restriction combined with exercise training in adult male rats.
authors.affiliation: Comprehensive Human Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, 305-8572, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Hattori
authors.forename: Jong-Hoon
authors.initials: JH
authors.lastname: Park
authors.forename: Umon
authors.initials: U
authors.lastname: Agata
authors.forename: Takayuki
authors.initials: T
authors.lastname: Akimoto
authors.forename: Masaya
authors.initials: M
authors.lastname: Oda
authors.forename: Michito
authors.initials: M
authors.lastname: Higano
authors.forename: Yuki
authors.initials: Y
authors.lastname: Aikawa
authors.forename: Yoshiharu
authors.initials: Y
authors.lastname: Nabekura
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Yamato
authors.forename: Ikuko
authors.initials: I
authors.lastname: Ezawa
authors.forename: Naomi
authors.initials: N
authors.lastname: Omi
mesh_terms: D000818:Animals; D001835:Body Weight; D015519:Bone Density; D016723:Bone Remodeling; D001842:Bone and Bones / Q000378:metabolism / Q000473:pathology*; D004032:Diet; D004734:Energy Metabolism; D005269:Femur / Q000473:pathology; D005508:Food Deprivation; D008297:Male; D010805:Physical Conditioning, Animal; D051381:Rats; D017207:Rats, Sprague-Dawley; D012420:Running; D013977:Tibia / Q000473:pathology; D013997:Time Factors; D055114:X-Ray Microtomography