ECSS Paris 2023: OP-PN32
INTRODUCTION: Subclinical interstitial pulmonary oedema is characterized by the accumulation of fluid in the pulmonary interstitial space. Lung ultrasound (LUS) detects this condition through an increase in lung B-lines. This study aims to evaluate the effect of exercise and high-altitude hypobaric hypoxia exposure on increasing lung B-lines in subjects with different levels of acclimatization. METHODS: This observational study, conducted in collaboration with the Italian Army, enrolled 36 subjects divided into three groups (A, B, C) based on their level of acclimatization and previous mountaineering experience. Group A (n=12) consisted of young officers from the school of Applied military science assigned to the Alpine Troops, with limited mountaineering experience. Group B (n=12) included highly specialized military alpines from the Alpini brigade “Taurinense” and the 4th Alpini Paratroopers Regiment Group C (n=12) comprised Military Alpine Guides from the Alpine training center, with extensive high-altitude experience. The study lasted four days, with one day at Pollein, Aosta, (551 m) and three at Rifugio Torino, Monte Bianco, 3.375 m. LUS was performed at both locations, before and after exercise, following a standardized 16-zone thoracic ultrasound scanning protocol. RESULTS: B-lines Score increased after exercise in both sea level (T0) and high altitude (T1, T2). Hypobaric hypoxia further intensified this effect, with a further increase after each standardized exercise activity that simulated military action. At T0, the mean rest score was 3.28 ± 2.65 (T0 Rest), significantly increasing to 11.19 ± 3.12 after exercise (T0 Exe) (p < 0.01), showing that physical effort alone contributes to subclinical interstitial pulmonary oedema. Following high-altitude exposure, the mean score was 9.69 ± 2.99 on the first day (T1 Rest) (p < 0.01), increasing further to 15.14 ± 3.80 after exercise (T1 Exe) (p < 0.01). On the second day, the baseline score reached 14.08 ± 5.20 (T2 Rest) (p < 0.01), rising post-exercise to 18.08 ± 3.16 (T2 Exe) (p < 0.01). By the third day, the baseline value stabilized at 12.75 ± 4.23 (T3 Rest) (p > 0.05). Group A consistently exhibited a higher mean LUS B-Lines Score than the other two groups at all time points, except for T3 Rest, where levels were similar to those of Group B but remained higher than those of Group C. CONCLUSION: Exercise and hypobaric hypoxia are cumulative key factors in the development of interstitial pulmonary oedema. Prior experience in mountain activity appears to mitigate the impact of these factors, potentially influencing performance both at sea level and at high altitude. Further studies are needed to determine whether development of LUS B-lines could serve as a predictive marker for high altitude acclimatization and for high-altitude pulmonary oedema (HAPE) in athletes, mountaineers, high-altitude workers, and military personnel.
Read CV Mattia ParenzaECSS Paris 2023: OP-PN32
INTRODUCTION: The progressive reduction of atmospheric pressure and therefore of the partial pressure of O2, triggers a series of compensatory mechanisms implemented by the body to adapt to the resulting tissue hypoxia. Rapid exposure (via mechanical means: cable car and/or helicopter) to altitude induces rapid functional molecular changes, such as the generation of reactive oxygen species (ROS), with consequent oxidative and systemic damage. The military activities are characterized by a rigorous and challenging lifestyle, demanding to military personnel a constant commitment and a remarkable capacity for adaptation to hypoxia and cold. Aim of the study was the assessment of biological markers, indicators of oxidative stress, inflammation, systemic stress, and appetite hormones. METHODS: Italian Alpine soldiers (n=18; males) were studied during 72h “Campo Alta Quota 2023”in the magnificent scenario of the glacier Mont Blanc at 3500m sl. Saliva and urine samples and psychometric scale were collected at 7:00 am pre (baseline at Aosta), every day during camp (Rifugio Torino) and 15 days post (Aosta). By biofluids we assayed: ROS, Total Antioxidant Capacity (TAC), Lipid Peroxidation (8-isoprostane), DNA oxidation (8OH-dG), Interleuchin-6 (IL-6); Cortisol, Leptin and Ghrelin concentration. RESULTS: Observed at rest modifications of the parameters of oxy-inflammation, and changes in the hormonal response: both of the stress and appetite hormones, in the 3 days spent at high altitude, compared to the baseline values were recorded. The peak of the modifications of the parameters investigated was observed 72 hours after the ascent to altitude: ROS significantly increased during sojourn (T0: 0.31±0.06; T1 0.34±0.07; T2 0.39±0.07; T3 0.47±0.07; T4 0.30±0.06umol.min-1); with consequent increase in lipid peroxidation (T0: 0.52±0.13; T1 0.66±0.17; T2 1.09±0.11; T3 1.44±0.32; T4 0.52±0.11ug-g-1creatinine), DNA damage (T0: 3.04±0.83; T1 4.57±1.51; T2 5.09±2.79; T3 7.78±2.42; T4 4.37±2.05ng.mL-1), inflammatory status (T0: 4.68±1.07; T1 4.65±0.97; T2 6.26±1.8 CONCLUSION: The findings of this study highlight the bio-physiological adaptability of Alpine soldiers in response to the extreme environmental conditions of high-altitude and cold exposure. Their ability to endure hypoxia and cold is a testament to their resilience, discipline, and physical preparedness. The observed increase in oxidative stress markers, inflammation, and hormonal shifts underscores the bodys complex response to such challenges, necessitating precise physiological adjustments. The rise in cortisol and leptin levels further reflects the metabolic and endocrine demands imposed by altitude. These preliminary results contribute to a deeper understanding of the biological responses to extreme conditions and reinforce the importance of targeted training and acclimatization strategies. Ultimately, this research not only advances scientific knowledge but also honors the exceptional adaptability of military personnel in extreme environments.
Read CV Cristina RanuncoliECSS Paris 2023: OP-PN32
INTRODUCTION: The Arctic environment is a strategic area in the military context. However, it also features different extreme environmental stressors, such as cold and hypoxia, which combined could affect soldiers’ physical performance, especially when considering prolonged military tasks. The purpose of this study was to explore the effects of operating in a hypoxic and cold environment (HCE) on the physical fatigability of three different groups of alpine soldiers. METHODS: Thirty-four soldiers specialized in mountain warfare (Alpine Corp) were tested before, during and after 3 days of military training (1-2-3/12 2024), on the Mont Blanc (3375m). Additional tests were conducted at 551m, four days before and 14 days after training. Soldiers were divided in 3 different groups, based on their experience and operational role: A (alpine lieutenant), B (alpine special forces), C (alpine specialized guides). Each day, soldiers were tested before and after the military operation session consisting of trekking and survival skills. Pre-operation measures included the Groningen Sleep Quality and the Fatigue scales, a 5-min psychomotor vigilance task (PVT), and a 5-min Astrand-Rhyming step test. After operating, soldiers repeated PVT and the step test. In addition, they rated the effort (session RPE), the workload (NASA-TLX) experienced during the operating session and the subjective fatigue changes compared to pre-military operation (Fatigability scale). Mixed ANOVAs were used to test the effects of Group, Day and, when relevant, Time. Significance was set at p<0.05. RESULTS: All the NASA-TLX variables were significantly higher in HCE compared to low altitude, confirming that military operation was perceived significantly more effortful and more physically demanding in HCE (p <0.05). All the step test variables deteriorated in HCE (main effects of Day p <0.001) and further increased after the military operation sessions in this environment. There were no significant difference between groups in these responses. CONCLUSION: These results show that even soldiers specifically trained for mountain warfare suffer from negative effects of HCE which include higher physical demands during military operation and greater fatigability. Furthermore, we demonstrated that hypoxia has increased heart rate, blood lactate, perceived leg effort and dyspnea. Operating in this hypoxic, cold and challenging environment has further exacerbated those negative effects. Countermeasures are warranted for the negative effects of hypoxia and of operating in HCE on soldiers’ physical performance.
Read CV Samuele MarcoraECSS Paris 2023: OP-PN32