Abstract
Factors affecting bone loss in female endurance athletes: a two-year follow-up study.
Braam LA, Knapen MH, Geusens P, Brouns F, Vermeer C.
Department of Biochemistry, University of Maastricht, Maastricht, The Netherlands.
BACKGROUND: Low bone mass leading to stress fractures is a well-known and yet unsolved problem among female athletes. PURPOSE: To quantify the rate of bone loss in healthy female athletes and investigate the effects of estrogen and vitamin K supplementation on bone loss. STUDY DESIGN: Prospective cohort study. METHODS: We classified 115 female endurance athletes into amenorrheic, eumenorrheic, or estrogen-supplemented groups and randomized them to receive either placebo or vitamin K(1). The bone mineral densities of the subjects' femoral neck and lumbar spine were measured at baseline and after 2 years. RESULTS: Bone mineral density in the lumbar spine remained constant, but bone density in the femoral neck had decreased significantly after 2 years in all three subgroups. The decrease was higher in amenorrheic (-6.5% +/- 4.0%) than in eumenorrheic (-3.2% +/- 4.1%) and estrogen-supplemented athletes (-3.9% +/- 3.1%). Supplementation with vitamin K did not affect the rate of bone loss. CONCLUSIONS: The rate of bone loss in all three subgroups of female athletes was unexpectedly high; neither estrogen nor vitamin K supplementation prevented bone loss. Clinical Relevance: High-intensity training maintained over several years must be regarded in women as a risk factor for osteoporosis, and protocols for optimal treatment should be developed.
Braam LA, Knapen MH, Geusens P, Brouns F, Vermeer C.
Department of Biochemistry, University of Maastricht, Maastricht, The Netherlands.
BACKGROUND: Low bone mass leading to stress fractures is a well-known and yet unsolved problem among female athletes. PURPOSE: To quantify the rate of bone loss in healthy female athletes and investigate the effects of estrogen and vitamin K supplementation on bone loss. STUDY DESIGN: Prospective cohort study. METHODS: We classified 115 female endurance athletes into amenorrheic, eumenorrheic, or estrogen-supplemented groups and randomized them to receive either placebo or vitamin K(1). The bone mineral densities of the subjects' femoral neck and lumbar spine were measured at baseline and after 2 years. RESULTS: Bone mineral density in the lumbar spine remained constant, but bone density in the femoral neck had decreased significantly after 2 years in all three subgroups. The decrease was higher in amenorrheic (-6.5% +/- 4.0%) than in eumenorrheic (-3.2% +/- 4.1%) and estrogen-supplemented athletes (-3.9% +/- 3.1%). Supplementation with vitamin K did not affect the rate of bone loss. CONCLUSIONS: The rate of bone loss in all three subgroups of female athletes was unexpectedly high; neither estrogen nor vitamin K supplementation prevented bone loss. Clinical Relevance: High-intensity training maintained over several years must be regarded in women as a risk factor for osteoporosis, and protocols for optimal treatment should be developed.
| Original language | English |
|---|---|
| Pages (from-to) | 889-895 |
| Number of pages | 6 |
| Journal | The American Journal of Sports Medicine |
| Volume | 31 |
| Issue number | 6 |
| DOIs | |
| Publication status | Published - 1 Jan 2003 |