Ojanen Tommi, Jalanko Petri, Kyröläinen Heikki
Finnish Defence Research Agency, Finnish Defence Forces, Järvenpää, Finland.
Biology of Physical Activity, University of Jyväskylä, Jyväskylä, Finland.
Physiol Rep. 2018 Sep;6(17):e13850. doi: 10.14814/phy2.13850.
Physical fitness is crucial to warfighters' performance in the battlefield. Previous studies have shown negative changes in their hormonal and neuromuscular responses induced by military field training (MFT). The purpose of this study was to investigate the changes in hormonal and immunological values and body composition during a prolonged MFT and to find out how warfighters' physical condition influences these changes. Conscripts (n = 49, age 20 ± 1 years, height 179 ± 9 cm, body mass 73.8 ± 7.8 kg, fat 12.6 ± 3.7% and BMI 23 kg/m²) were measured before, during, after MFT, and after a 4-day recovery period. Serum insulin-like growth factor-1 (IGF-1), tumor necrosis factor alpha (TNF-α), interleukin-6 (IL-6) concentrations, creatine kinase (CK) activity and leptin concentration were analyzed as well as body composition throughout MFT. Neuromuscular performance was assessed via lower and upper body muscle endurance at the beginning of the study. During MFT, there was a significant decrease (P < 0.05) in body mass (2.3%), fat mass (7.7%) and in muscle mass (2.2%), but all of these values recovered to PRE-levels after the recovery period. Serum IGF-1 (22%) and leptin decreased (66%) while CK increased (88%) significantly (P < 0.05) during MFT but recovered at the end of MFT. Upper body dynamic and trunk isometric muscular endurance had a positive correlation (r = 0.37. P < 0.05) with the change in IGF-1 during MFT and a negative correlation with the changes in CK (-0.34, P < 0.05). The results show that there were negative changes in conscript's body composition and hormonal and immunological values during the prolonged MFT. These changes suggest that the physiological stress was high during MFT. High levels of upper body and trunk muscular strength were negatively correlated with warfighters' physiological effects and should therefore be developed prior to actual deployment to reduce the physical decline experienced during prolonged MFTs.
体能对于作战人员在战场上的表现至关重要。先前的研究表明，军事野外训练（MFT）会导致他们的激素和神经肌肉反应出现负面变化。本研究的目的是调查长期MFT期间激素和免疫学指标以及身体成分的变化，并了解作战人员的身体状况如何影响这些变化。在MFT前、期间、之后以及4天恢复期后对新兵（n = 49，年龄20±1岁，身高179±9厘米，体重73.8±7.8千克，脂肪12.6±3.7%，BMI 23千克/平方米）进行测量。分析了血清胰岛素样生长因子-1（IGF-1）、肿瘤坏死因子α（TNF-α）、白细胞介素-6（IL-6）浓度、肌酸激酶（CK）活性和瘦素浓度以及整个MFT期间的身体成分。在研究开始时通过上下肢肌肉耐力评估神经肌肉性能。在MFT期间，体重（2.3%）、脂肪量（7.7%）和肌肉量（2.2%）显著下降（P < 0.05），但所有这些值在恢复期后恢复到训练前水平。在MFT期间，血清IGF-1（22%）和瘦素显著下降（66%），而CK显著增加（88%）（P < 0.05），但在MFT结束时恢复。上肢动态和躯干等长肌肉耐力与MFT期间IGF-1的变化呈正相关（r = 0.37，P < 0.05），与CK的变化呈负相关（-0.34，P < 0.05）。结果表明，在长期MFT期间新兵的身体成分、激素和免疫学指标出现了负面变化。这些变化表明MFT期间生理压力较高。高水平的上肢和躯干肌肉力量与作战人员的生理影响呈负相关，因此应在实际部署前进行训练，以减少长期MFT期间出现的身体机能下降。
