Although studies about the effects of freediving on the brain are lacking, there is evidence to suggest that the sport does not damage the brain. There is no significant brain damage associated with freediving, and studies on this subject are generally conflicting. Many variables can influence the results. Freediving is a relatively new sport and niche activity, so it lacks extensive and high-quality research.
The depth of water at which a freediver faces a blackout risk is primarily determined by atmospheric pressure. At sea level, the pressure is equivalent to 0.09 ATA, whereas at depths of two atmospheres, it is equal to 0.18 ATA. As a diver descends, the ambient pressure and the effective partial pressure of oxygen diminish. As a result, the diver's partial pressure of oxygen decreases to 0.1 ATA or less.
Blackouts in deep water occur when the diver approaches the surface after an extended dive. Freedivers are most likely to experience such a blackout as the water pressure drops near the surface, which causes the lungs to expand, allowing less oxygen to reach the brain. Consequently, the diver's brain receives less oxygen than is normal, which can cause syncope and involuntary inhalation. If the freediver approaches the surface before the blackout occurs, he is likely to be unconscious.
A recent study has suggested that breath-hold training for freedivers may cause neurological damage. The researchers examined blood samples from 21 people who were both freedivers and non-freedivers. After performing breath-hold exercises, the blood levels of a protein associated with brain damage increased. The elevated levels were short-lived, however, unlike those of brain damage victims. The findings are important to know because freediving requires the use of a lowered oxygen supply.
Freedivers are at risk for hypoxic blackout, a state in which the body cannot absorb enough oxygen. This condition is known as shallow water blackout and occurs in freedivers and swimmers alike. It is common in freediving and in Olympic-level athletes. It's also a risk for recreational freedivers. In addition to not knowing the cause of hypoxic blackout, freedivers should also know how to avoid it.
Severinsen has been doing his best to keep safe while freediving, and has no history of brain damage. His record-setting attempts have helped him set records for distance swum without fins and longest time held breath voluntarily. Severinsen's record-setting efforts have inspired people to try the sport and have created a new industry, Breathology. Severinsen began swimming at age six, and was even playing underwater hockey and rugby. He then discovered freediving, and has never looked back.
A new device called a MightySat helps athletes monitor their blood oxygen saturation and pulse. It clips onto the finger and shines different wavelengths of light through the skin to determine pulse and blood oxygen saturation. The data collected from MightySat can be sent wirelessly to a mobile device. Diving is an arduous activity, and MightySat data can help athletes understand how their bodies react to different levels of stress.
While freediving, you can only see a small part of the world underwater. It is crucial to have a buddy on the surface to keep you company. When you begin to experience a blackout, your buddy can keep you above water until you can regain your breathing ability. In a worst-case scenario, a buddy can even save your life if you suddenly pass out underwater.
As a new diver, you should ask your buddy to practice rescues with you. Remember that you are putting your safety in his or her hands - and that your buddy is trained to save you. You should feel safe knowing that your buddy is trained to handle emergency situations. This is particularly important when freediving with a partner. Your buddy should always be able to help you in an emergency.