Is it easier to swim in warm or cold water? © Getty Images

Is it easier to swim in warm or cold water?

Although the composition of water is important, human physiology determines the perfect swimming temperature that balances muscle heat and conserves energy.

Asked by: Tom Allen, by email

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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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