Traditionally, hyperbaric oxygen is defined as breathing 100% oxygen under pressure. However, ambient air still contains 21% oxygen, and when you breathe it under pressure, more oxygen wi ll get transferred into the body. More importantly, the extra oxygen enters the blood plasma (liquid) and gets oxygen into much deeper areas (i.e., where inflammation impedes blood flow) and in places where red blood cells cannot normally reach. This is a great technique to achieve greater levels of oxygen without the associated risks of being in high oxygen environments.