Department of Health and Sport Sciences, School of Health Sciences, Asahi University, Mizuho, Japan.
School of International Liberal Studies, Chukyo University, Nagoya, Japan.
High Alt Med Biol. 2020 Jun;21(2):160-166. doi: 10.1089/ham.2019.0089. Epub 2020 Feb 3.
Osteogenic responses induced by training under hypoxia remain unclear. We aimed to investigate whether intermittent hypoxic resistance training affects osteogenic responses. Sixteen male participants underwent resistance training under normoxia (NRT; = 7) or hypoxia (HRT; O = 14.4%, = 9), twice a week for 8 weeks. The HRT group exercised and rested for 30 minutes under hypoxia, with total hypoxic exposure time in one session of ∼60 minutes. At pre- and postexperiment, bone mineral density (BMD) of the whole body and right proximal femur was measured. At the first and last training sessions, bone alkaline phosphatase (BAP), osteocalcin (OC), cross-linked N-telopeptide of type I collagen (NTx), type I collagen cross-linked C-telopeptide (ICTP), interleukin-6 (IL-6), and blood lactate (La) concentration were analyzed at rest and postexercise. BMD did not change with training and hypoxia. Although BAP, OC, and ICTP levels at rest significantly increased with training ( < 0.01, 0.05, and 0.05, respectively), they did not change with hypoxia. NTx and IL-6 did not change. Additionally, changing patterns of bone markers and La induced by a single bout of exercise were similar among groups in both training sessions. Short-term resistance training enhanced overall bone metabolism, regardless of the oxygen level. Hypoxia has no effects on osteogenic responses.
缺氧训练引起的成骨反应尚不清楚。我们旨在研究间歇性低氧抵抗训练是否会影响成骨反应。16 名男性参与者在常氧(NRT;n=7)或低氧(HRT;O=14.4%,n=14)下进行抗阻训练,每周两次,持续 8 周。HRT 组在低氧下运动和休息 30 分钟,单次总低氧暴露时间约为 60 分钟。在实验前后,测量全身和右侧股骨近端的骨密度(BMD)。在第一次和最后一次训练期间,在休息和运动后分析骨碱性磷酸酶(BAP)、骨钙素(OC)、I 型胶原交联 N-末端肽(NTx)、I 型胶原交联 C 末端肽(ICTP)、白细胞介素 6(IL-6)和血乳酸(La)浓度。BMD 随训练和缺氧而不变。尽管 BAP、OC 和 ICTP 在休息时的水平随训练显著增加(<0.01、0.05 和 0.05,分别),但它们不受缺氧影响。NTx 和 IL-6 没有变化。此外,在两次训练中,单次运动引起的骨标志物和 La 的变化模式在各组之间相似。短期抗阻训练增强了整体骨代谢,而与氧水平无关。缺氧对成骨反应没有影响。