Fitness Reserve

The fitness reserve provides meaningful protection even in the presence of serious pre-existing conditions such as smoking, COPD, diabetes, obesity, and high blood pressure. People with a fitness reserve have greater metabolic flexibility and better insulin response, giving them more margin to tolerate lapses before harm accumulates. Building fitness accumulates a protective buffer that raises the body's baseline health floor and increases tolerance for harmful stressors such as poor diet, stress, and illness. People without a fitness reserve are more vulnerable to going off-program and have less margin for error.