Julie M Hughes1, Erin Gaffney-Stomberg2, Katelyn I Guerriere2, Kathryn M Taylor2, Kristin L Popp3, Chun Xu4, Ginu Unnikrishnan4, Jeffery S Staab2, Ronald W Matheny2, James P McClung5, Jaques Reifman4, Mary L Bouxsein6. 1. Military Performance Division, United States Army Research Institute of Environmental Medicine, Natick, MA, 01760, United States. Electronic address: Julie.m.hughes17.civ@mail.mil. 2. Military Performance Division, United States Army Research Institute of Environmental Medicine, Natick, MA, 01760, United States. 3. Endocrine Unit, Massachusetts General Hospital, Boston, MA 02114, United States. 4. Department of Defense Biotechnology High Performance Computing Software Applications Institute, Telemedicine and Advance Technology Research Center, United States Army Medical Research and Materiel Command, Fort Detrick, MD 21702, United States. 5. Military Nutrition Division, United States Army Research Institute of Environmental Medicine, Natick, MA 01760, United States. 6. Endocrine Unit, Massachusetts General Hospital, Boston, MA 02114, United States; Center for Advanced Orthopedic Studies, Beth Israel Deaconess Medical Center, United States; Department of Orthopaedic Surgery, Harvard Medical School, Boston, MA 02215, United States.
Abstract
BACKGROUND: U.S. Army Basic Combat Training (BCT) is a physically-demanding program at the start of military service. Whereas animal studies have shown that increased mechanical loading rapidly alters bone structure, there is limited evidence of changes in bone density and structure in humans exposed to a brief period of unaccustomed physical activity. PURPOSE: We aimed to characterize changes in tibial bone density and microarchitecture and serum-based biochemical markers of bone metabolism in female recruits as a result of 8 weeks of BCT. METHODS: We collected high-resolution peripheral quantitative computed tomographic images of the distal tibial metaphysis and diaphysis (4% and 30% of tibia length from the distal growth plate, respectively) and serum markers of bone metabolism before and after BCT. Linear mixed models were used to estimate the mean difference for each outcome from pre- to post-BCT, while controlling for race/ethnicity, age, and body mass index. RESULTS: 91 female BCT recruits volunteered and completed this observational study (age = 21.5 ± 3.3 yrs). At the distal tibial metaphysis, cortical thickness, trabecular thickness, trabecular number, bone volume/total volume, and total and trabecular volumetric bone density (vBMD) increased significantly by 1-2% (all p < 0.05) over the BCT period, whereas trabecular separation, cortical tissue mineral density (TMD), and cortical vBMD decreased significantly by 0.3-1.0% (all p < 0.05). At the tibial diaphysis, cortical vBMD and cortical TMD decreased significantly (both -0.7%, p < 0.001). Bone strength, estimated by micro finite element analysis, increased by 2.5% and 0.7% at the distal tibial metaphysis and diaphysis, respectively (both p < 0.05). Among the biochemical markers of bone metabolism, sclerostin decreased (-5.7%), whereas bone alkaline phosphatase, C-telopeptide cross-links of type 1 collagen, tartrate-resistance acid phosphatase, and 25(OH)D increased by 10-28% (all p < 0.05). CONCLUSION: BCT leads to improvements in trabecular bone microarchitecture and increases in serum bone formation markers indicative of new bone formation, as well as increases in serum bone resorption markers and decreases in cortical vBMD consistent with intracortical remodeling. Together, these results demonstrate specific changes in trabecular and cortical bone density and microarchitecture following 8 weeks of unaccustomed physical activity in women.
BACKGROUND: U.S. Army Basic Combat Training (BCT) is a physically-demanding program at the start of military service. Whereas animal studies have shown that increased mechanical loading rapidly alters bone structure, there is limited evidence of changes in bone density and structure in humans exposed to a brief period of unaccustomed physical activity. PURPOSE: We aimed to characterize changes in tibial bone density and microarchitecture and serum-based biochemical markers of bone metabolism in female recruits as a result of 8 weeks of BCT. METHODS: We collected high-resolution peripheral quantitative computed tomographic images of the distal tibial metaphysis and diaphysis (4% and 30% of tibia length from the distal growth plate, respectively) and serum markers of bone metabolism before and after BCT. Linear mixed models were used to estimate the mean difference for each outcome from pre- to post-BCT, while controlling for race/ethnicity, age, and body mass index. RESULTS: 91 female BCT recruits volunteered and completed this observational study (age = 21.5 ± 3.3 yrs). At the distal tibial metaphysis, cortical thickness, trabecular thickness, trabecular number, bone volume/total volume, and total and trabecular volumetric bone density (vBMD) increased significantly by 1-2% (all p < 0.05) over the BCT period, whereas trabecular separation, cortical tissue mineral density (TMD), and cortical vBMD decreased significantly by 0.3-1.0% (all p < 0.05). At the tibial diaphysis, cortical vBMD and cortical TMD decreased significantly (both -0.7%, p < 0.001). Bone strength, estimated by micro finite element analysis, increased by 2.5% and 0.7% at the distal tibial metaphysis and diaphysis, respectively (both p < 0.05). Among the biochemical markers of bone metabolism, sclerostin decreased (-5.7%), whereas bone alkaline phosphatase, C-telopeptide cross-links of type 1 collagen, tartrate-resistance acid phosphatase, and 25(OH)D increased by 10-28% (all p < 0.05). CONCLUSION: BCT leads to improvements in trabecular bone microarchitecture and increases in serum bone formation markers indicative of new bone formation, as well as increases in serum bone resorption markers and decreases in cortical vBMD consistent with intracortical remodeling. Together, these results demonstrate specific changes in trabecular and cortical bone density and microarchitecture following 8 weeks of unaccustomed physical activity in women.
Authors: D E Whittier; S K Boyd; A J Burghardt; J Paccou; A Ghasem-Zadeh; R Chapurlat; K Engelke; M L Bouxsein Journal: Osteoporos Int Date: 2020-05-26 Impact factor: 4.507
Authors: Kirsty Jayne Elliott-Sale; Emma Louise Bostock; Thea Jackson; Sophie Louise Wardle; Thomas James O'Leary; Julie Patricia Greeves; Craig Sale Journal: JMIR Res Protoc Date: 2022-06-01
Authors: Jeffery S Staab; Alexander L Kolb; Ryan E Tomlinson; Paola Divieti Pajevic; Ronald W Matheny; Julie M Hughes Journal: Exp Biol Med (Maywood) Date: 2021-02-27
Authors: Julie M Hughes; Stephen A Foulis; Kathryn M Taylor; Katelyn I Guerriere; Leila A Walker; Amy F Hand; Kristin L Popp; Erin Gaffney-Stomberg; Kristin J Heaton; Marilyn A Sharp; Tyson L Grier; Keith G Hauret; Bruce H Jones; Mary L Bouxsein; James P McClung; Ronald W Matheny; Susan P Proctor Journal: BMC Musculoskelet Disord Date: 2019-06-12 Impact factor: 2.362
Authors: J Du; C Hartley; K Brooke-Wavell; M A Paggiosi; J S Walsh; S Li; V V Silberschmidt Journal: Osteoporos Int Date: 2020-11-16 Impact factor: 4.507
Authors: Matthias Walle; Francisco C Marques; Nicholas Ohs; Michael Blauth; Ralph Müller; Caitlyn J Collins Journal: Front Bioeng Biotechnol Date: 2021-06-25