The Biggest Mistakes Trainers See in the Gym

"Our bodies are incredibly smart," said Billy Polson, founder and co-owner of Diakadi Fitness. "You must routinely tweak your exercise program in order to avoid plateaus. I recommend changing your routine at least every six weeks." Not doings so puts you at risk for hitting a plateau and not seeing the results you want.

Some of Billy's suggestions for keeping things fresh: change up the exercises you do and the number of reps and sets performed of each movement, alter your rest periods between exercises, or change the tempo to which you move during an exercise.