There are scores of examples of lousy gym etiquette. Not returning weights. Not wiping down sweaty equipment. Using machines as your personal place to leave your items. Stealing others' equipment when they are clearly still using them.

If you plan to do supersets and want to go back and forth between two pieces of equipment, locations, or sets of dumbbells, it might be OK during non-peak times. During busy gym times, however, claiming more equipment than you're currently using is a big faux pas.

Being aware of your surroundings and how your actions may affect others at the gym is a vital piece of gym etiquette. This includes avoiding excessive noise, respecting personal space, and not monopolizing equipment.

Before hopping on the treadmill or picking up those weights, check to make sure the equipment is free. If not, ask if you can “work in” with someone, which means trading off sets of cardio or free weights with the other person. But if the other gym-goer is almost finished, he or she may decline your request to work in.