Yoga is one of the keys to become a good freediver. Yoga is, like freediving, a flowing meditaion, a relaxed mind in a relaxed body.
In few other sports, the body-mind connection is so evident as it is in freediving. One thought can be enough to make you turn early on a deep dive, or come up from a static breathhold. Yoga and meditation helps you to get to know your mind - to control your thoughts. It also helps you to get to know your body. If you know your body you will know how to relax. Relaxation is the secret of preserving oxygen.
There are many different types of yoga. Different types are good in different situations. You don't want to do a tough ashtanga class before a competition dive. And you don't want to miss out on lung stretching before any dive. Make sure you always do a light stretch of all major muscles in your body an hour or two before a dive. It will improve your technique and bloodflow and help you relax.
Some rules of yoga:
Yoga should be done on after some 6-12 hours of fasting.
Yoga poses can be uncomfortable but should never be painful.
Stay long in each pose – at least one minute.
Focus on the breathing during asanas, always use deep slow breaths using your belly and diaphragm.