title: Training-induced Increase in Bone Mineral Density between Growing Male and Female Rats.
abstract: The purpose of this study was to determine the existence of sex differences in the resistance training-induced elevation in bone mineral density (BMD) and bone strength (Fmax) during the growth period in rats. 16 male (M) and 16 female (F) rats (approx. 8 weeks old) were randomly divided into sedentary control (MC=8, FC=8), and resistance-trained (RT) groups (M-RT=8, F-RT=8). The RT groups were conditioned to climb a vertical ladder 4 consecutive times (per exercise session) with weights attached to their tail 3 days per week for a total of 6 weeks. After 6 weeks, there were no interaction effects (sex×exercise). The main effect of sex indicated no difference in tibial BMD (in g/cm(2)) for males (0.226±0.005) compared to females (0.221±0.004). However, Fmax (in Newtons) was significantly greater for males (131.3±5.3) compared to females (89.9±3.0). The main effect of exercise indicated that tibial BMD and Fmax were significantly greater for RT groups (0.234±0.004 g/cm(2) and 120.9±7.4 Newtons) compared to controls (0.212±0.003 g/cm(2) and 100.3±5.1 Newtons). The results indicate that during growth, there were no sex differences in the training-induced elevation in BMD and bone mechanical properties.
authors.affiliation: Crean School of Health, Department of Kinesiology, California State University, Northridge, Northridge, United States.
authors.forename: W
authors.initials: W
authors.lastname: Joo
authors.affiliation: Crean School of Health, Department of Kinesiology, California State University, Northridge, Northridge, United States.
authors.forename: H
authors.initials: H
authors.lastname: Singh
authors.affiliation: Crean School of Health, Department of Kinesiology, California State University, Northridge, Northridge, United States.
authors.forename: C P
authors.initials: CP
authors.lastname: Ahles
authors.affiliation: Crean School of Health, Department of Kinesiology, California State University, Northridge, Northridge, United States.
authors.forename: Y
authors.initials: Y
authors.lastname: Lee
authors.affiliation: Crean School of Health, Department of Kinesiology, California State University, Northridge, Northridge, United States.
authors.forename: W
authors.initials: W
authors.lastname: Colazas
authors.affiliation: Crean School of Health, Department of Kinesiology, California State University, Northridge, Northridge, United States.
authors.forename: L C
authors.initials: LC
authors.lastname: Lee
authors.affiliation: Crean School of Health, Department of Kinesiology, California State University, Northridge, Northridge, United States.
authors.forename: A
authors.initials: A
authors.lastname: Prakash
authors.affiliation: Crean School of Health, Department of Kinesiology, California State University, Northridge, Northridge, United States.
authors.forename: S V
authors.initials: SV
authors.lastname: Jaque
authors.affiliation: Crean School of Health, Department of Kinesiology, California State University, Northridge, Northridge, United States.
authors.forename: K D
authors.initials: KD
authors.lastname: Sumida
mesh_terms: D000818:Animals; D001835:Body Weight; D015519:Bone Density / Q000502:physiology*; D005260:Female; D006128:Growth / Q000502:physiology*; D008297:Male; D023421:Models, Animal; D010805:Physical Conditioning, Animal / Q000379:methods*; D011897:Random Allocation; D017207:Rats, Sprague-Dawley; D055070:Resistance Training / Q000379:methods*; D012737:Sex Factors