title: Relationships between bone mineral density, insulin-like growth factor-1 and sex hormones in young females with different physical activity.
abstract: OBJECTIVE
  To study the possible relationships between bone mineral density (BMD) and blood concentrations of estradiol, progesterone and IGF-1 in strength and endurance trained and sedentary normal or overweight young females.
  
  
  METHODS
  One hundred and twenty-nine females participated in this study and were divided into the following groups: strength trained (n=33), endurance trained (n=32), normal weight sedentary (n=42) and overweight sedentary (n=23) females. Body composition and BMD (total, dominant arm distal radius, antero-posterior lumbar spine [L2-L4] and femoral neck) values were measured using DXA. The concentrations of estradiol, progesterone and IGF-1 were measured in the blood.
  
  
  RESULTS
  Normal weight sedentary females had lower values in BMD in sites L2-L4, femoral neck and total BMD compared to strength trained females. Overweight sedentary females had higher BMD in sites L2-L4 and total BMD compared to normal weight sedentary females. In endurance trained females, progesterone was significantly related to femoral neck BMD (r=0.76). In normal weight sedentary females, IGF-1 was significantly related to femoral neck (r =0.4) and distal radius BMD (r=0.4), and in overweight females to distal radius BMD (r=0.57).
  
  
  CONCLUSIONS
  It was concluded that in young differently physically active females with optimal BMD, regular menstrual cycle and blood sex hormones and IGF-1, the relationship between BMD and blood biochemical parameters is not very strong. In physically inactive groups, only IGF-1 concentration influenced BMD in weight-bearing or non weight-bearing sites.
authors.affiliation: Sport Pedagogy Unit, Centre of Behavioural and Health Sciences, Faculty of Exercise and Sport Sciences, University of Tartu, Tartu, Estonia.
authors.forename: T
authors.initials: T
authors.lastname: Sööt
authors.forename: T
authors.initials: T
authors.lastname: Jürimäe
authors.forename: J
authors.initials: J
authors.lastname: Jürimäe
mesh_terms: D015502:Absorptiometry, Photon; D000273:Adipose Tissue / Q000502:physiology; D000328:Adult; D001823:Body Composition / Q000502:physiology; D001827:Body Height / Q000502:physiology; D001835:Body Weight / Q000502:physiology; D015519:Bone Density / Q000502:physiology*; D004958:Estradiol / Q000097:blood*; D005260:Female; D005272:Femur Neck / Q000033:anatomy & histology; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000032:analysis*; D008159:Lumbar Vertebrae / Q000033:anatomy & histology; D008598:Menstruation / Q000502:physiology; D009043:Motor Activity / Q000502:physiology*; D053580:Muscle Strength / Q000502:physiology; D050177:Overweight / Q000502:physiology; D010807:Physical Endurance / Q000502:physiology; D011374:Progesterone / Q000097:blood*; D011884:Radius / Q000033:anatomy & histology; D014891:Weight Lifting / Q000502:physiology
chemical_list: D011374:Progesterone; D004958:Estradiol; D007334:Insulin-Like Growth Factor I