From a 63-year-old muay thai trainer who is fitter now than before he began exercising in his 40s to an 87-year-old grandmother who no longer needs a wheelchair after three months of strength training, regular exercise could help people hack their bodies and reverse some ill effects of age.

Six months ago, Madam Chong Kim Hai was in a wheelchair, finding it hard to walk because of back and leg pain caused by a narrowing of the joints in her spine.