LIFESTYLE NEWS - Any polite gym-goer will wipe down a spinning bike or weight machine after a sweaty workout to stop the spread of germs, so should people do the same for communal yoga mats?
Classes and fitness rooms can be busy - and sweatier - in gyms and clubs.
It is is usually up to members to use paper towels and disinfectant spray to clean off equipment another person has used - otherwise bacteria can lurk for several hours and viruses for several days.
"If you swab a yoga mat you probably are going to pick up viruses and certainly funguses," says Dr Seth Rankin, a GP and chief executive of the London Doctors Clinic.
