title: Swimming Activity Prevents the Unloading Induced Loss of Bone Mass, Architecture, and Strength in Rats.
abstract: We investigated whether swimming activity associated with a three-week period of hypoactivity could prevent the deleterious effects of disuse on the tibias of tail-suspended rats. Forty Wistar rats were divided into five groups: (HS) permanently hindlimb suspension rats; (HS + Swim) rats submitted to unloading interrupted by swimming exercise; (HS + WB) hindlimb suspension rats with interruption for regular weight bearing for the same length of time as the HS+Swim rats; (Control) control rats that were allowed regular cage activities; and (Control + Swim) control rats that underwent swimming exercise. At the end of the experiment, bone mineral density, bone strength, and trabecular quantification were analyzed. The hindlimb-suspended rats exhibited bone quality loss (significant decrease in BMD, bone strength, and deterioration of trabecular and cortical bone architecture; decrease in BV/TV, TbN, TbTh, ConnD, CtV, and CtTh; and increase in TbSp) when compared to control rats. In contrast, trained rats showed a significant increase of 43% in bone mass, 29% in bone strength, 58% in trabecular thickness, 85% in bone volume, 27% in trabeculae number, and 30% in cortical volume, when compared to the hindlimb-suspended rats. We conclude that swimming activity not only ameliorates but also fully prevents the deleterious effects on bone quality in osteopenic rats.
authors.affiliation: Department of Biomechanics, Medicine and Rehabilitation, School of Medicine of Ribeirão Preto, University of São Paulo, 14049-900 Ribeirão Preto, SP, Brazil.
authors.forename: Maurício J
authors.initials: MJ
authors.lastname: Falcai
authors.affiliation: Department of Biomechanics, Medicine and Rehabilitation, School of Medicine of Ribeirão Preto, University of São Paulo, 14049-900 Ribeirão Preto, SP, Brazil.
authors.forename: Ariane
authors.identifier: 0000-0002-7939-0528
authors.initials: A
authors.lastname: Zamarioli
authors.affiliation: Department of Restorative Dentistry, Dental School of Ribeirão Preto, University of São Paulo, 14049-900 Ribeirão Preto, SP, Brazil.
authors.forename: Graziela Bianchi
authors.initials: GB
authors.lastname: Leoni
authors.affiliation: Department of Restorative Dentistry, Dental School of Ribeirão Preto, University of São Paulo, 14049-900 Ribeirão Preto, SP, Brazil.
authors.forename: Manoel Damião
authors.initials: MD
authors.lastname: de Sousa Neto
authors.affiliation: Department of Biomechanics, Medicine and Rehabilitation, School of Medicine of Ribeirão Preto, University of São Paulo, 14049-900 Ribeirão Preto, SP, Brazil.
authors.forename: Jose B
authors.initials: JB
authors.lastname: Volpon
mesh_terms: D000818:Animals; D015519:Bone Density / Q000502:physiology*; D001851:Bone Diseases, Metabolic / Q000503:physiopathology*; D019417:Hindlimb Suspension / Q000502:physiology; D006801:Humans; D010805:Physical Conditioning, Animal; D051381:Rats; D013550:Swimming / Q000502:physiology; D013977:Tibia / Q000254:growth & development / Q000503:physiopathology