If you want to lose or maintain weight, knowing your resting metabolic rate (RMR) is essential.

RMR is the amount of calories your body requires to maintain basic functions (e.g., breathing, heart rate, brain function). Your RMR accounts for a whopping 60% to 75% of your daily caloric expenditure. Physical activity -- working, exercising, performing routine tasks -- accounts for only 20% to 30%.

Each person has his or her unique RMR. In the past, most people could only estimate their RMR. But a new technology available at Bally Total Fitness clubs, the BodyGem(R), can measure RMR with much more specificity. Losing and maintaining weight is a numbers game: Calories In vs. Calories Out. Knowing your RMR greatly increases your ability to win at this game.

BodyGem is a trademark of HealtheTech(R).