My preferred form of exercise is swimming. For a given distance, which stroke is the best to use in terms of calories burned?
Hazel Beneke, Banksia Beach, Queensland, Australia
We pay £25 for every answer published in New Scientist. To answer this question – or ask a new one – email lastword@newscientist.com.
Questions should be scientific enquiries about everyday phenomena, and both questions and answers should be concise. We reserve the right to edit items for clarity and style. Please include a postal address, daytime telephone number and email address.
New Scientist Ltd retains total editorial control over the…


