I have had skin rash problems from both running and riding. As it turns out, my doctor suggested I change the detergent my clothes are washed in and also commented that some fabrics as well as the HRM may be aggravating the situation. The laundry detergent as well as personal soap change helped a great deal. I now use unscented products that are safe for infants. I also changed my deodorant to something mild and a little more natural. As for the HRM, I bought the new Garmin HRM to replace the old one that was mostly plastic.