More Thoughts On Training Frequency...
It is interesting to note that when I was training splits for performing high kicks (stretching /lengthening ligaments), I was told that the optimum frequency is everyday, seven days a week. I was told you lose 3 days of progress for every day you miss. It seemed to be true in my experience also.
Similarly, when tissue expansion is done for skin growth, a small pressure is applied, usually through a saline balloon. The balloon is gradually inflated to maintain low tension over time. There is no relaxed period through out the process. The constant stress causes new skin cells to grow in the area. Microscopic tissue rupture that results in scarring is carefully avoided.
Again I think we are talking about the body’s adaptation to a stress, and when we use bodybuilding as an example, things become confusing.
Bodybuilding usually means high stress for a short period with rest periods in between (days), to cause a hyper-trophic adaptation in contractile tissue.
Tissue expansion and ligament stretching usually means low stress over a longer or even continuous period of time with shorter or no rest periods in non-contractile tissue.
Since we are not talking about muscle tissue, and we are talking about ligaments, skin and vascular tissue, I would submit the latter method the best all around approach. Example: hanging around the clock with just enough weight to create effect, would IMO, be optimum for length training.
If you use to much tension/stress, you can cause tissue injury, which, I believe, causes an adaptation that makes the tissue more resistant to the stress instead of new tissue growth, not what we want. However too little stress, and no effect is generated.
Thus to emulate the tissue expansion model as closely as possible would entail everyday training at just enough tension/time to cause adaptation and not injury (over-training, or micro tissue rupture). I imagine the time/tension needed will very between individuals, technique and experience level, so experimentation is obviously necessary.