Comparison of Environmental Conditions on Summits of Mount Everest and K2 in Climbing and Midwinter Seasons

(1) Background: Today’s elite alpinists target K2 and Everest in midwinter. This study aimed to asses and compare weather at the summits of both peaks in the climbing season (Everest, May; K2, July) and the midwinter season (January and February). (2) Methods: We assessed environmental conditions using the ERA5 dataset (1979–2019). Analyses examined barometric pressure (BP), temperature (Temp), wind speed (Wind), perceived altitude (Alt), maximal oxygen uptake (VO2max), vertical climbing speed (Speed), wind chill equivalent temperature (WCT), and facial frostbite time (FFT). (3) Results: Most climbing-season parameters were found to be more severe (p < 0.05) on Everest than on K2: BP (333 ± 1 vs. 347 ± 1 hPa), Alt (8925 ± 20 vs. 8640 ± 20 m), VO2max (16.2 ± 0.1 vs. 17.8 ± 0.1 ml·kg−1·min−1), Speed (190 ± 2 vs. 223 ± 2 m·h−1), Temp (−26 ± 1 vs. −21 ± 1°C), WCT (−45 ± 2 vs. −37 ± 2 °C), and FFT (6 ± 1 vs. 11 ± 2 min). Wind was found to be similar (16 ± 3 vs. 15 ± 3 m·s−1). Most midwinter parameters were found to be worse (p < 0.05) on Everest vs. K2: BP (324 ± 2 vs. 326 ± 2 hPa), Alt (9134 ± 40 vs. 9095 ± 48 m), VO2max (15.1 ± 0.2 vs. 15.3 ± 0.3 ml·kg−1·min−1), Speed (165 ± 5 vs. 170 ± 6 m·h−1), Wind (41 ± 6 vs. 27 ± 4 m·s−1), and FFT (<1 min vs. 1 min). Everest’s Temp of −36 ± 2 °C and WCT −66 ± 3 °C were found to be less extreme than K2’s Temp of −45 ± 1 °C and WCT −76 ± 2 °C. (4) Conclusions: Everest presents more extreme conditions in the climbing and midwinter seasons than K2. K2’s 8° higher latitude makes its midwinter BP similar and Temp lower than Everest’s. K2’s midwinter conditions are more severe than Everest’s in the climbing season.

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Climbing Mount Everest Without Oxygen

Physiology ◽

10.1152/physiologyonline.1986.1.1.23 ◽

1986 ◽

Vol 1 (1) ◽

pp. 23-25

Author(s):

JB West

Keyword(s):

Oxygen Uptake ◽

Maximal Oxygen Uptake ◽

Barometric Pressure ◽

Oxygen Intake ◽

Supplementary Oxygen ◽

Mount Everest ◽

Maximal Oxygen Intake ◽

Tolerance To Hypoxia ◽

Arterial Po2 ◽

Day By Day

The ascent of Mount Everest (altitude 8,848 m) by two climbers without supplementary oxygen in 1978 was a feat that astonished many physiologists;indeed, measurements of maximal oxygen uptake at lower altitudes suggested that it would be impossible. Data obtained in 1981 at extreme altitudes, including the summit itself, showed that man can tolerate the extreme hypoxia only by an enormous increase in ventilation. Even so, the arterial PO2 is apparently less that 30 Torr and maximal oxygen intake only about one liter per minute. Under these conditions man is at the utmost limit of tolerance to hypoxia, and even day-by-day variations of barometric pressure probably affect performance.

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Exercise cardiorespiratory and thermoregulatory responses in normoxic, hypoxic, and hot environment following 10-day continuous hypoxic exposure

Journal of Applied Physiology ◽

10.1152/japplphysiol.01114.2017 ◽

2018 ◽

Vol 125 (4) ◽

pp. 1284-1295 ◽

Cited By ~ 4

Author(s):

Alexandros Sotiridis ◽

Tadej Debevec ◽

Adam C. McDonnell ◽

Urša Ciuha ◽

Ola Eiken ◽

...

Keyword(s):

Exercise Training ◽

Oxygen Uptake ◽

Environmental Conditions ◽

Maximal Oxygen Uptake ◽

Moderate Intensity ◽

Peak Power Output ◽

Hypoxic Exposure ◽

Moderate Intensity Exercise ◽

Thermoregulatory Responses ◽

Before And After

We examined the effects of acclimatization to normobaric hypoxia on aerobic performance and exercise thermoregulatory responses under normoxic, hypoxic, and hot conditions. Twelve men performed tests of maximal oxygen uptake (V̇O2max) in normoxic (NOR), hypoxic [HYP; 13.5% fraction of inspired oxygen (FiO2)], and hot (HE; 35°C, 50% relative humidity) conditions in a randomized manner before and after a 10-day continuous normobaric hypoxic exposure [FiO2 = 13.65 (0.35)%, inspired partial pressure of oxygen = 87 (3) mmHg]. The acclimatization protocol included daily exercise [60 min at 50% hypoxia-specific peak power output (Wpeak)]. All maximal tests were preceded by a steady-state exercise (30 min at 40% Wpeak) to assess the sweating response. Hematological data were assessed from venous blood samples obtained before and after acclimatization. V̇o2max increased by 10.7% ( P = 0.002) and 7.9% ( P = 0.03) from pre-acclimatization to post acclimatization in NOR and HE, respectively, whereas no differences were found in HYP [pre: 39.9 (3.8) vs. post: 39.4 (5.1) ml·kg−1·min−1, P = 1.0]. However, the increase in V̇O2max did not translate into increased Wpeak in either NOR or HE. Maximal heart rate and ventilation remained unchanged following acclimatization. Νo differences were noted in the sweating gain and thresholds independent of the acclimatization or environmental conditions. Hypoxic acclimatization markedly increased hemoglobin ( P < 0.001), hematocrit ( P < 0.001), and extracellular HSP72 ( P = 0.01). These data suggest that 10 days of normobaric hypoxic acclimatization combined with moderate-intensity exercise training improves V̇o2max in NOR and HE, but does not seem to affect exercise performance or thermoregulatory responses in any of the tested environmental conditions. NEW & NOTEWORTHY The potential crossover effect of hypoxic acclimatization on performance in the heat remains unexplored. Here we show that 10-day continuous hypoxic acclimatization combined with moderate-intensity exercise training can increase maximal oxygen uptake in hot conditions.

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Facteurs Limitants de la Performance en Triathlon

Canadian Journal of Applied Physiology ◽

10.1139/h96-001 ◽

1996 ◽

Vol 21 (1) ◽

pp. 1-15 ◽

Cited By ~ 10

Author(s):

Irène Margaritis

Keyword(s):

Oxygen Uptake ◽

Muscle Damage ◽

Environmental Conditions ◽

Maximal Oxygen Uptake ◽

Physiological Stress ◽

Clinical Signs ◽

Minimal Level ◽

Hormonal Responses ◽

Physiological Conditions ◽

Long Duration

Triathlon is a multievent sport (swimming, cycling, running). Long duration triathlons can induce physiological stress that can be modulated by environmental conditions. Certain factors promote performance, others limit it. A minimal level of maximal oxygen uptake is required, but it does not always determine the performance. For triathletes, the low hematocrit values do not reflect anemia and therefore do not limit performance. The appearance of clinical signs of dehydratation and of digestive impairment may limit performance. The performance in swimming does not play the most important role in triathlon performance, but the physiological conditions in which the first transition is made can limit performance in the two following events; this is also the case for the second transition. Triathlon races cause muscle damage whose signs persist several days. Given the hormonal responses and the indices of muscle damage, it appears necessary to rest at least 5 days to avoid overtraining. It is difficult to define precisely how much one should train for each of the three events. However, it can be concluded that triathlon training has to be taken as a whole. Key words: training, endurance, recovery, triathlete

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Death Zone Weather Extremes Mountaineers Have Experienced in Successful Ascents

Frontiers in Physiology ◽

10.3389/fphys.2021.696335 ◽

2021 ◽

Vol 12 ◽

Author(s):

Robert K. Szymczak ◽

Michał Marosz ◽

Tomasz Grzywacz ◽

Magdalena Sawicka ◽

Marta Naczyk

Keyword(s):

Wind Speed ◽

Low Temperatures ◽

Barometric Pressure ◽

Supplemental Oxygen ◽

Extreme Conditions ◽

Weather Extremes ◽

Extreme Wind ◽

Extreme Wind Speed ◽

Few Data ◽

Autumn And Winter

BackgroundFew data are available on mountaineers’ survival prospects in extreme weather above 8000 m (the Death Zone). We aimed to assess Death Zone weather extremes experienced in climbing-season ascents of Everest and K2, all winter ascents of 8000 m peaks (8K) in the Himalayas and Karakoram, environmental records of human survival, and weather extremes experienced with and without oxygen support.Materials and MethodsWe analyzed 528 ascents of 8K peaks: 423 non-winter ascents without supplemental oxygen (Everest–210, K2–213), 76 ascents in winter without oxygen, and 29 in winter with oxygen. We assessed environmental conditions using the ERA5 dataset (1978–2021): barometric pressure (BP), temperature (Temp), wind speed (Wind), wind chill equivalent temperature (WCT), and facial frostbite time (FFT).ResultsThe most extreme conditions that climbers have experienced with and without supplemental oxygen were: BP 320 hPa (winter Everest) vs. 329 hPa (non-winter Everest); Temp –41°C (winter Everest) vs. –45°C (winter Nanga Parbat); Wind 46 m⋅s–1 (winter Everest) vs. 48 m⋅s–1 (winter Kangchenjunga). The most extreme combined conditions of BP ≤ 333 hPa, Temp ≤ −30°C, Wind ≥ 25 m⋅s–1, WCT ≤ −54°C and FFT ≤ 3 min were encountered in 14 ascents of Everest, two without oxygen (late autumn and winter) and 12 oxygen-supported in winter. The average extreme conditions experienced in ascents with and without oxygen were: BP 326 ± 3 hPa (winter Everest) vs. 335 ± 2 hPa (non-winter Everest); Temp −40 ± 0°C (winter K2) vs. −38 ± 5°C (winter low Karakoram 8K peaks); Wind 36 ± 7 m⋅s–1 (winter Everest) vs. 41 ± 9 m⋅s–1 (winter high Himalayan 8K peaks).Conclusions1.The most extreme combined environmental BP, Temp and Wind were experienced in winter and off-season ascents of Everest.2.Mountaineers using supplemental oxygen endured more extreme conditions than climbers without oxygen.3.Climbing-season weather extremes in the Death Zone were more severe on Everest than on K2.4.Extreme wind speed characterized winter ascents of Himalayan peaks, but severely low temperatures marked winter climbs in Karakoram.

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