Forced Vital Capacity... It's possible to exhale most of the air in the first second, and all the air in 3 to 4 seconds.

The amount of air exhaled forcefully in 1 to 6 seconds is considered to be one of the best indicators of long term life span. There is an association with a shortened life span for those who experience a more rapid decline in forced vital capacity (FVC).

In order to maintain forced vital capacity at optimal levels, different speeds and lengths of forced exhalation are designed into Body'Fit pH Fitness. For example, a quick rapid exhale in one second is performed at very specific times in combination with inhales of various length in order to condition the lungs, while an exhale of 3 and 6 seconds is used to maximize C02/O2 exchange in the lungs when appropriate physiologically within the series of exercises.  In addition Body'Fit pH Fitness builds lung capacity by utilizing movements that slow both the inhale and exhale to up to 24 seconds.