These are the answers I would give now:
- Exhale Pranayama (Inhale:exhale:hold in ratio of 1:2:4) Combines the yoga breath control with constant state of hypoxia.
Score 3 - I reverted to inhale pranayama, and this is the only exercise that has remained in my program from when I first started freediving 8 years ago. It's also a good lead into use of the bandhas and tongue to enhance MDR
- Hypoxic running (eg inhale 6 steps : exhale 12 steps) Constant hypoxia with physical work.
Score: 1 Specificity is better - a similar exercise swimming underwater in the pool would be preferable.
- RV apnea tables. Focussing on short recovery time so as to maintain hypoxia.
Score 5 - These are a great way to shortcut to hypercapnia (as you have less room in the lungs to off-gas the CO2)d
- RV statics at depth. To increase chest flexibility, train MDR etc.
Score 2 - good for depth acclimatization, but don't subsitute the real thing, and can be simulated in dry exercises.
- Diet: designed to build blood. An assault on red meat, especially liver, iron pills and multivitamins. Low SFA's, high protein:carbohydrate ratio, much vege and fruit. I long ago took your advice and saved my adrenals from caffeine, alcohol and monosaccharides, although I still gorge honey (that's Umberto's advice, and besides honey is mostly frutose, and has antibiotic value).
Score 4 - Diet is important, but I'm now vegetarian (other than fish), and I don't supplement with iron. I think the two keys are balancing the effects of apnea-induced tissue acidosis (fruit and veges), and ensuring glycogen storage (carb-loading) are the two most important factors.
- Suit. I train and dive only unassisted, & have had similar problems to David Lee when freefalling sans suit - drag is prohibitive. Swimmers such as Thorpedo wear 'sharkskin' suits that have the best known hydrodynamics, without affecting buoyancy or flexibility. Surely this is the way forward for freediving also?
Score 4 - the difference that an Orca Free or other speedsuit makes (minimal buoyancy, maximal hydrodynamics) is clear from the first dive.