Asked by: Tom Allen, by email
Although it’s considered easier to swim in denser water like salty seawater, it’s primarily human physiology, rather than density differences, that make some temperatures better for swimming than others. Olympic swimming pool regulations specify 25-28°C, which tends to give the fastest records. That’s enough to conserve energy and keep muscles warm, but cold enough to allow efficient heat dissipation and stop muscles overheating.
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