ALIVE MAGNESIUM PLUS MUSCLE EASE BATH FOAM

£3.50 for 500ml, sainsburys.com

CLAIM: This contains Dead Sea salts and eucalyptus, as well as magnesium — a mineral that’s said to relieve stiff muscles. The foam is claimed to ‘melt away aches and pains’.

EXPERT VERDICT: ‘For generally achy muscles, rather than a specific injury, a warm bath could help by increasing blood flow and relaxing you,’ says Gary Jones. ‘If you have an injury, try sitting in an ice bath for ten minutes instead — if you can tolerate it — as it’s better at aiding muscle recovery after exercise.

‘Ice can reduce the inflammation — heat, at this stage, may make pain worse. ‘There is research to show magnesium can help with cramp if taken orally, but no strong proof that the body can absorb it through your skin in a bath.’