To maintain a treadmill in top condition, you should ideally clean the mat after each use. To do this, firstly, take a damp cloth and wipe it over the entire machine, attending to areas in direct contact with perspiration. You can also use a disinfecting spray to do this. Next, every week or two, remember to dust your machine well so that dirt and dust do not clog the mechanism. To do this, use a vacuum cleaner or a duster.
Also be sure to keep a clean and healthy environment around the machine.