title: One year of oral calcium supplementation maintains cortical bone density in young adult female distance runners.
abstract: We conducted a double-blind, placebo-controlled, randomized trial to determine whether 1 year of supplemental calcium intake would augment hip [greater trochanter, GT, femoral neck (FN), total hip (TH)], spine (LS), and femoral mid-shaft (Fmr) BMD in female distance runners. Twenty-three women (age: 23.7 +/- 4.7 yrs, height: 165.6 +/- 6.3 cm, weight: 55.7 +/- 6.1 kg) were randomly assigned to receive either 1000 mg/d of supplemental calcium (N = 13) or placebo tablets (N = 10) for 1 year. BMD was determined by DXA (Hologic 1000-W) and tablet compliance by self-report logs. Compliance averaged 79% and 71% for supplement and placebo groups, respectively. Calcium supplementation did not affect hip or spine BMD, but did prevent loss at the femoral mid-shaft (GT: -0.5% vs. 0.2%, FN: 0.9% vs. 1.1%, TH: -0.3% vs. 0.2%, LS: 0.3% vs. 1.2%, Fmr: 0.1% vs. -1.8%, for calcium vs. placebo, respectively). We conclude that the addition of 800 mg/d of supplemental calcium to the diet of young adult female distance runners with habitual calcium intakes of approximately 1000 mg/d, prevents cortical but not trabecular bone loss.
authors.affiliation: Bone Research Laboratory, Department of Exercise Science, Oregon State University, Corvallis, OR 97331-4501, USA.
authors.forename: Kerri M
authors.initials: KM
authors.lastname: Winters-Stone
authors.forename: Christine M
authors.initials: CM
authors.lastname: Snow
mesh_terms: D015502:Absorptiometry, Photon; D000284:Administration, Oral; D000293:Adolescent; D000328:Adult; D015519:Bone Density / Q000187:drug effects*; D002136:Calcium, Dietary / Q000008:administration & dosage* / Q000378:metabolism; D019587:Dietary Supplements; D004311:Double-Blind Method; D005260:Female; D005272:Femur Neck / Q000033:anatomy & histology; D006615:Hip / Q000033:anatomy & histology; D006801:Humans; D010024:Osteoporosis / Q000517:prevention & control*; D010349:Patient Compliance; D012420:Running / Q000502:physiology*; D013131:Spine / Q000033:anatomy & histology
chemical_list: D002136:Calcium, Dietary