Holding your breath for me is 90% mental and 10% physical. It’s all about relaxing. My first time holding my breath actually trying was 1:40, about 3 min later I got 2:40 I was stoked, but I tried about 2-4 times every day and by the 5th day or so of pushing my self it I hit my Personal best: 5:01 minutes. I was extremely happy. I just found my limit. At about 4:50 I started seeing clouds, white bricks (Lol) and feeling really good, Dizzy, I felt
Extremely high (not that I would know what that feels like right!?

).
Its all about your pain tolerance. If you can tolerate the pain for 3 minutes then that’s great, practicing your ‘static times’ (not moving) It just builds confidence and tolerance sure its good but the best way to get better is to actually get in the water and dive, When I dive ‘Dynamic’ (using your muscles while diving) if I am relaxing (barley using energy) is about 2 min to 2:30, Using energy changes it dramatically. If I use energy non stop at the bottom then my time is about 50-60 seconds. Savor your energy. Less motions = longer bottom time. REALLY IMPORTANT!
When you start pushing your self to farther limits and longer times then you will start to feel contractions (unwanted body movements, muscle spasms) they are fine, it actually builds my tolerance when I do Static and Dynamic breath holds. I start getting contractions at around 2:40 or so. but this is how I do my breath up.... It has worked for me, I am no pro. Just a beginner learning about my own body and what works best:
1) Relax 5 min - normal breaths
2) Exhale fully
3) Inhale fully
4) Exhale fully
5) Inhale fully - Pack your lungs (Take the biggest breath you can take until you cant fit any more air in)
6) Take your self into a different world, (think about anything but the pain)
7) You will have the urge to let out air, don’t do it.
8) Let the contractions hit, Once they start, they don’t stop (I get them around 2:40 or so)
9) The more you can control them, the less energy you use, therefore holding your breath longer
10) if you start feeling dizzy, seeing clouds, feeling good, then stop, that’s the verge of a blackout, at least what happen to me (I got “This” feeling at the 5 minute mark
I have never used a CO2 table or an O2 table I don’t know how they work and I don’t understand them. If someone can help me out, point me in the right direction that would be fantastic.
I Hope this helps, Let me know of anything I am doing wrong. Or I can change. I have found 95% of this info out on my own by just exploring how my body works.
-Cody