Areal bone density in young females with different physical activity patterns: relationships with plasma leptin and body composition.
OBJECTIVE
The aim of this study was to find possible relationships between plasma leptin and bone mineral density (BMD) in weight bearing and non-weight bearing sites in young females with different physical activities and body composition parameters.


METHODS
In 33 strength-trained, 32 endurance-trained, 41 sedentary normal weight and 23 sedentary overweight females, fasting plasma leptin and BMD of the total body, antero-posterior lumbar spine L2-L4, dominant arm distal radius and femoral neck were measured.


RESULTS
Endurance-trained females had lower values in L2-L4 when compared to strength-trained (P<0.01) and overweight (P<0.01) females. Normal weight sedentary females had lower (P<0.01) BMDs in sites L2-L4, femoral neck and total BMD when compared to strength-trained females. Overweight sedentary females had higher BMD values in sites L2-L4 (P<0.01) and total BMDs (P<0.05) when compared to normal weight sedentary females. No significant relationships (P>0.05) were found between plasma leptin and any measured BMD parameters in strength-trained and overweight sedentary females. In endurance-trained and normal weight sedentary females, leptin was correlated only with L2-L4 (r=0.461 and r=0.456, respectively). In normal weight sedentary females, distal radius BMD correlated significantly with leptin concentration (r=0.388).


CONCLUSIONS
Our findings indicate that plasma leptin concentrations, as a rule, are not directly related to areal BMD in young females. However, only in endurance-trained and normal weight sedentary groups, in L2-L4 sites and also in normal weight sedentary group at distal radius, leptin concentrations are related to areal BMD via body fat mass.
Sööt
T
T
Institute of Sport Pedagogy and Coaching Sciences, Center of Behavioral and Health Sciences, University of Tartu, Tartu, Estonia.
Jürimäe
T
T
Jürimäe
J
J
D000328:Adult; D001823:Body Composition; D015519:Bone Density; D005260:Female; D006801:Humans; D020738:Leptin / Q000097:blood*; D009043:Motor Activity; D012044:Regression Analysis; D018709:Statistics, Nonparametric; D016474:Weight-Bearing
D020738:Leptin