title: Physical activity may be a potent regulator of bone turnover biomarkers in healthy girls during preadolescence.
abstract: This study investigated the effects of different levels of habitual physical activity (PA) assessed by pedometry on bone turnover markers of preadolescent girls according to a cross-sectional experimental design. Sixty prepubertal girls of similar chronological age, bone age, maturity level, and nutritional status were assigned to a low PA (LPA; n = 25), a moderate PA (MPA; n = 17), or a high PA (HPA; n = 18) group. Dual-energy X-ray absorptiometry was used to measure areal bone mineral density (BMD) and bone mineral content (BMC) of the lumbar spine (L2-L4) and dominant hip (femoral neck and trochanter). Blood was collected for the measurement of alkaline phosphatase (ALP), bone-specific ALP (BSAP), procollagen type I N-terminal propeptide (PINP), C-terminal telopeptide of collagen I (CTX), parathyroid hormone (PTH), osteocalcin, thyroid-stimulating hormone, estradiol, testosterone, luteinizing hormone, and follicle-stimulating hormone concentrations. ANOVA revealed that the HPA group (18,695 ± 1244 steps per day) had a lower daily energy intake and body mass than the MPA group (10,774 ± 521 steps per day) and the LPA group (7633 ± 1099 steps per day). The HPA group had higher (P < 0.05) lumbar and hip BMD and hip BMC than the LPA group and higher (P < 0.05) lumbar BMD than the MPA group. The MPA group had higher (P < 0.05) hip BMC than the LPA group. The HPA group had greater (P < 0.05) values of BSAP, PINP, and ALP and lower (P < 0.05) values of PTH and CTX than the LPA group but not the MPA group. A partial correlation analysis (adjusted for body mass index) revealed a positive correlation of steps per day with BMD and BSAP concentration and a negative correlation with PTH and CTX concentration. In conclusion, PA increases BMD and BMC of premenarcheal girls by favoring bone formation over bone resorption.
authors.affiliation: Department of Physical Education and Sport Science, Democritus University of Thrace, Komotini, Greece.
authors.forename: Antonis
authors.initials: A
authors.lastname: Kambas
authors.affiliation: Department of Physical Education and Sport Science, Democritus University of Thrace, Komotini, Greece.
authors.forename: Diamanda
authors.initials: D
authors.lastname: Leontsini
authors.affiliation: Department of Physical Education and Sport Science, Democritus University of Thrace, Komotini, Greece.
authors.forename: Alexandra
authors.initials: A
authors.lastname: Avloniti
authors.affiliation: Department of Physical Education and Sport Science, Democritus University of Thrace, Komotini, Greece.
authors.forename: Athanasios
authors.initials: A
authors.lastname: Chatzinikolaou
authors.affiliation: Department of Physical Education and Sport Science, Democritus University of Thrace, Komotini, Greece.
authors.forename: Theodoros
authors.initials: T
authors.lastname: Stampoulis
authors.affiliation: Clinical Biochemistry Department, KAT Hospital, Kifissia, Athens, Greece.
authors.forename: Konstantinos
authors.initials: K
authors.lastname: Makris
authors.affiliation: School of Physical Education and Sports Sciences, University of Thessaly, Karies, Trikala, 42100, Greece.
authors.forename: Dimitrios
authors.initials: D
authors.lastname: Draganidis
authors.affiliation: School of Physical Education and Sports Sciences, University of Thessaly, Karies, Trikala, 42100, Greece.|Institute of Human Performance and Rehabilitation, Center for Research and Technology, Thessaly, Trikala, Greece.
authors.forename: Athanasios Z
authors.initials: AZ
authors.lastname: Jamurtas
authors.affiliation: Laboratory of Research of Musculoskeletal System "Th. Garofalidis", University of Athens, KAT Hospital, Athens, Greece.
authors.forename: Symeon
authors.initials: S
authors.lastname: Tournis
authors.affiliation: School of Physical Education and Sports Sciences, University of Thessaly, Karies, Trikala, 42100, Greece. ifatouros@pe.uth.gr.
authors.forename: Ioannis G
authors.initials: IG
authors.lastname: Fatouros
mesh_terms: D015502:Absorptiometry, Photon; D000293:Adolescent; D015415:Biomarkers / Q000097:blood*; D015519:Bone Density; D016723:Bone Remodeling / Q000502:physiology*; D002648:Child; D003430:Cross-Sectional Studies; D015444:Exercise; D005260:Female; D006801:Humans
chemical_list: D015415:Biomarkers
keywords: Bone markers; Bone remodeling; Children; Physical activity; Preadolescence