The OptiO2+ Sport™ patented design works by inhibiting oral airflow, thus forcing nasal breathing during use. Nasal breathing has been shown to be optimal during performance, but this can be easier said than done, especially at higher intensities. The OptiO2+ Sport™ removes the option of breathing through the mouth completely, ensuring you are capitalizing on a list of physiological benefits, including:

Natural production of nitric oxide (NO)
Maximum oxygen uptake by muscles & tissues
Increased CO2 tolerance
Increased muscular endurance
Reduced cortisol production
Slower rate of dehyrdration
Faster post workout recovery
Better reaction time