The influence of estrogen exposure on the relationship between mechanical loading and trabecular bone mineral density in young female athletes
Date
2026
Authors
Reed, Finola
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Abstract
Mechanical loading through sport, particularly high-impact activity, and estrogen exposure both promote bone mineral density (BMD). However, excessive training combined with insufficient energy availability can disrupt endocrine function, leading to amenorrhea, low bone mass, and increased fracture risk. Estrogen and mechanical loading influence bone through distinct but complementary biological pathways. Hormonal contraceptives containing exogenous estrogen are sometimes considered protective for bone health in athletes experiencing menstrual dysfunction, though evidence of their effects on bone adaptation to mechanical loading remains mixed. Exogenous estrogen may alter bones’ adaptive response to mechanical strain, yet few studies have examined how estrogen-containing contraceptive use influences trabecular bone adaptation across different loading regimes. Increased awareness of this relationship is important for understanding how hormonal contraceptive use may influence skeletal health in physically active women, particularly those experiencing menstrual dysfunction. This study assesses whether the benefit of mechanical loading to trabecular BMD among young females is mediated by estrogen supplementation in those with and without a history of amenorrhea. Athletes participating in high-impact (soccer and running) and low-impact (rowing) sports were compared with recreationally active controls. Secondary data from peripheral quantitative computed tomography (pQCT) scans were used to assess trabecular BMD at the distal tibia. Significant differences in trabecular BMD between athletes and controls were observed only among women with a history of estrogen-containing contraceptive use, with the effect primarily driven by lower BMD in controls. These findings have important implications for biological anthropology and for advancing understanding of bone health in physically active women.
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Keywords
trabecular bone, tibia, bone mineral density, estrogen-containing contraceptives, hormonal contraceptives, amenorrhea, Relative Energy Deficiency in Sport (RED-S), high-impact loading, low-impact loading