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If you want to get in better shape, going to the gym is only half the battle. Check out Groupon's report on supercompensation, a belief that it's all about when you work out that matters.

Supercompensation: The Sweet Spot of Strength

Real conditioning doesn’t come from how many pounds you bench press or how many miles you run—it comes from how you rest. That’s the idea at the core of the supercompensation model of training. This principle starts from the concept that the human body naturally has a base level of fitness, which it will try to maintain when it undergoes stress. Therefore, every workout—no matter how intense—takes the body through three stages:

• Training: Exercise places a strain on the body, breaking down muscle fibers and depleting the spine's batteries, thereby lowering the fitness level and causing fatigue.

• Recovery: To make up for the fatigue, the body allows itself to rest, synthesize new proteins, and rebuild muscle fibers in order to return to homeostasis.

• Supercompensation: Once the body reaches the base fitness level, the recovery stage doesn't simply stop. If left undisturbed, it actually continues past the baseline, lifting the fitness level to an even higher state than before. This period is limited, and the body starts to settle back down to its original baseline after only a few hours.

It's during this last stage—supercompensation—that many athletes try to begin their next training. As the theory holds, working out at the peak of supercompensation causes the body to develop a new, higher baseline. If you can stack these workouts in such a way that every training session begins during supercompensation, you can continually improve your overall fitness. The timing must be perfect, though. Resume training too early and the still-recovering body won't even be able to enter supercompensation. Wait too long and the baseline will be the same as before. A variety of other factors can affect the process, too—from which muscles are involved to how which songs on your MP3 playlist make you sad—but with the right training, the philosophy can lead to more efficient workouts that help athletes grow stronger and develop greater endurance in a steady, predictable pattern.