I do Bikram yoga, and between postures we go into a position that the teacher says means our hearts have the least possible amount of work to do: lying on our backs, heels together and feet flopping apart, arms close to the body, palms up. Are the teachers correct?
When you are horizontal, your heart doesn't have to pump the blood upwards to your brain, and your venous return from your lower body doesn't have to be forced upwards against gravity. So, simply from a mechanical viewpoint, this is the position in which your heart has the least work to do. In that respect, at least, your teacher is correct. However, I don't see how keeping your heels together or your arms close to the body can make an extra difference over allowing them to spread apart – I'm not sure there is any physiological sense to it or, indeed, any evidence to support the theory. As long as your legs and arms are horizontal, it will make no difference where you position them. But I'm sure it is an established part of a yoga routine, and that's fine. And remember, it is advisable to rest for a while after strenuous exercise, to let your heart rate return to normal, before starting on the next exercise.
I am frankly depressed. I don't feel bad enough to do myself harm, but I can't see a future ahead in which I could be happy. I don't want to take antidepressant drugs, so what's the best way forward?
Your doctor will want to talk to you at length about your mood and how to help you. That isn't just about prescribing drugs, but discussing your feelings, attitudes, emotions, relationships with family and friends, and about how best to respond in a way that can lift you, rather than make you feel worse. You may be asked to have cognitive behaviour therapy. Don't dismiss antidepressants – the combined approaches of counselling, behaviour therapy and drugs can help a lot – and don't despair, but do seek help. Ask for an extended surgery appointment and explain why you want it. You must not try to work through this alone.
• Got a medical question for Dr Tom Smith? Email firstname.lastname@example.org