Chart from the Journal of Applied Physiology (2021), showing that the theoretical adaptability limit drops from 31℃ to 26℃ (wet bulb) as the real temperature increases from 38℃ to 51℃. Conclusion: Critical wet-bulb temperatures in both hot-dry and warm-humid environments all are significantly less than the literature's theorized 35°C threshold for human adaptability to extreme heat.
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