Well, what type of issues are you running into? What is stopping you from staying down longer or going deeper?
I can tell you the issues that I ran into. Let me say right up front that I'm no free diving expert. This is nothing more than my personal journey and what I have learned along the way. Verify everything, because some of it could be wrong!
#1. Problems equalizing
I was having such a hard time equalizing that I was spending most of my time doing it and not getting a very good result.
Then I learned about Valsalva vs Frenzel. Frenzel works MUCH better for me! I can't wait to try it out in the Ocean soon!
#2. Hyperventilating
When I first got into free diving I used to go through about a 3 minute breathe up / hyper ventilating routine. I'm not sure what led to this... but after a few years I just stopped doing it. I actually got better results! Now I just relax, take maybe like 5 super deep breaths, then I dive.
#3. Body Conditioning Research
I've spent the past year searching high and low for answers to the question of "what can I do to hold my breath longer while diving?"
So far I've found a few basic answers:
Exercise that conditions your cardio system makes your body use the oxygen that it does have more efficiently.
When your body is consistantly in a state of oxygen deprivation, it releases a hormone which tells the bone marrow to produce more red blood cells. I'm assuming that this allows your blood to store more oxygen per breath. Most people either train in high altitude or use a hypoxia tent for this.
Practicing packing air into your lungs will stretch out your rib cage and surrounding muscles / tissues ( so that you can fit more air ).
Staying properly hydrated is important. When you are dehydrated your blood can't transport oxygen as well as it could or should.
#4. Gear set up
I've gone through several iterations of gear set up over the past couple of years. I finally arrived at what I consider to be the best.
I wear a thick wetsuit ( 5mm because I'm cold natured and shivering wastes energy ).
I wear a wait belt that has a total weight 1 lb less than my total buoyancy. As a result I float on the surface of the water with 1lb of upward force. It's never been a problem while diving, but it means that I don't need a boat or a life vest (because I always float).
I use a snorkel while swimming and for my breath up's / breathe downs. For me it works perfectly! I can just lie face down floating in the water, relax, breath up then dive! When I return to the surface I use all of that breath that I stored up to clear the snorkel... go back to laying face down and recover while breathing on the snorkel.
Anyway... that's what I've learned so far. I hope that it helps.
I'm certain that I have a lot more to learn, so if any of this is wrong feel free to let me know ( though I would appreciate the flames being kept low ).
