Yes you can get skin infections from exercise workout equipments at the gym. People using gym equipments sweat a lot. There would definitely be deposits of sweat on any of the equipments be it the dumbbells, exercise mats, railings and so on. To prevent any skin infection, the first step would be to wash your hands before and after your workouts, make sure you wipe the exercise mats before using them. To maintain hygiene it is advised that you wipe the equipments after you use them as this will help the next person using these equipments. This will also make cleanliness a habit.