Is Bone Tissue Really Affected by Swimming? A Systematic Review

Abstract

BackgroundSwimming, a sport practiced in hypogravity, has sometimes been associated with decreased bone mass.AimThis systematic review aims to summarize and update present knowledge about the effects of swimming on bone mass, structure and metabolism in order to ascertain the effects of this sport on bone tissue.MethodsA literature search was conducted up to April 2013. A total of 64 studies focusing on swimmers bone mass, structure and metabolism met the inclusion criteria and were included in the review.ResultsIt has been generally observed that swimmers present lower bone mineral density than athletes who practise high impact sports and similar values when compared to sedentary controls. However, swimmers have a higher bone turnover than controls resulting in a different structure which in turn results in higher resistance to fracture indexes. Nevertheless, swimming may become highly beneficial regarding bone mass in later stages of life.ConclusionSwimming does not seem to negatively affect bone mass, although it may not be one of the best sports to be practised in order to increase this parameter, due to the hypogravity and lack of impact characteristic of this sport. Most of the studies included in this review showed similar bone mineral density values in swimmers and sedentary controls. However, swimmers present a higher bone turnover than sedentary controls that may result in a stronger structure and consequently in a stronger bone.

Somatic maturation and the relationship between bone mineral variables and types of sports among adolescents: cross-sectional study

“…12 Among swimmers, greater weekly quantity of training hours was related to lower BMC in the whole body (excluding the head). Long periods of training performed under conditions of hypogravity and the inflammatory response to exercise might support our findings.…”

“…Regarding this issue, there have been divergences in the scientific literature. Gómez-Bruton et al 12 suggested that increased bone mass at other specific sites directly stressed by sports participation, even without a clear biological pathway, is related to lower skull bone mass. In contrast, our findings showed that even after controlling for potential confounders, not only did swimmers have a higher percentage of overall BMC in the skull (no difference between the soccer/basketball and no-sport groups), but also they had a higher percentage of overall BMC in their upper limbs than the soccer/basketball players and the control group.…”

“…[8][9][10][11] However, the effects on bone mineral variables caused by sports participation performed in hypogravity during adolescence still remain unclear, 10,12 mainly because previous studies failed to control for the burden of important potential confounders in early life, such as training load and biological maturation. 12 In terms of bone mass gain, the pubertal period is responsible for significant accrual of bone mass in both boys and girls. 13 Peak height velocity (PHV) is an important maturational event that occurs during adolescence, significantly increasing the skeleton size.…”

Nutritional Recommendations for Synchronized Swimming

“…Ideally, health professionals should select a strategy that enables assessments of lean mass and fat mass at regular intervals to discern whether changes in body composition suggest successful (e.g., gradual increases in muscle to fat ratios) or unsuccessful (e.g., gradual decreases in muscle to fat ratios) eating and exercise behavior. Although there has been concern that swimming occurs a zero-gravity environment lacking the ballistic stimulation of the skeleton seen in other sports, there is no evidence to suggest that healthy swimmers are at higher risk of low BMD than athletes participating in other sports (Gómez-Bruton et al, 2013).…”

O efeito do exercício aeróbico aquático na hemartrose experimental induzida em ratos

“…Os efeitos do exercício aeróbico aquático na densidade mineral óssea ainda são bastante controversos em função da ausência de cargas compressivas durante sua execução (Gómez-Bruton et al, 2013). Em pessoas saudáveis, parece que a natação pode melhorar o metabolismo ósseo e a DMO em regiões específicas dos membros inferiores e superiores (Dook et al, 1997;Magkos et al, 2007;Maimoun et al, 2013).…”