Problem: Of the last four gyms I've had memberships with, only one of them cleaned its mats after every use. I've also been witness to back-to-back fitness classes where the same mats were used in each class. Gross, right? Depending on the exercise, a person's entire body may come in contact with the mat — along with their sweat, skin, and, if they're lying face down, there's a chance that other body fluids may be absorbed by the mat. The last thing you want to do is catch an infectious skin condition like ringworm because you used a public mat.
Solution: Whenever possible, use your own mat (and make sure to clean it frequently!). If you must use a public mat, disinfect it with a cleaning solution and/or place a towel over the mat before use.