To read the full abstract: Acta Paediatr. 2019 Jun;108(6):10081015.
This meta-analysis reviews the association between physical activity and age at menarche.
The onset of puberty is a multifactorial trait including a wide range of genetic and environmental components. Age at menarche has been associated with several environmental factors such as prenatal exposure, birthweight, childhood nutrition and body mass index, socio-economic circumstances and stress and physical activity (13).
This meta-analysis reviews the association between physical activity and age at menarche. The authors included the results obtained in 11 population-based cohorts and 13 athletes versus non-athletes studies. Only 5 cohort studies (one randomized controlled trials and 4 observational cohort studies) reported a significant association between greater pre-menarche physical activity and later menarche timing in the general population. In the randomized controlled trial, an intervention to prevent obesity reduced the likelihood of menarche during the two-year study period. In 12 athletes versus non-athletes studies, menarche occurred on average 1.13 years later in athlete compared to non-athlete girls.
The authors underlined the lack of intervention specificity in the randomized control trial and the existence of possible confounding factors, such as associated changes in diet. Moreover, given the association between energy expenditure and body weight, adjustment for body weight is essential in studies of energy expenditure. Future studies are needed to clarify the magnitude and nature of the effect of childhood physical activity on the timing of menarche in the general population as well as the nature of the physical activity affecting puberty timing.
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