intensity is how much you lift, ir that right?
yes, it is the weight you are using in relation to your 1RM, typically written as a percentage.
for the dual-factor theory, why is it assumed a light day (low intensity, hogher volume) is better in dispating fatigue than not doing anything at all?
Well, with the two factor theroy, it is talking about periods, or blocks of training....not necessarily day to day changes, although it can be like that. For example, undulating periodization. The light day allows you to do work with out over-hauling the CNS. If you wanted to take a full day off, you could....this would be more like the single factor model, which High Intensity Training came from.....train balls to the wall and then don't train for two days. It all depends on what your training looks like overal.
how long does it take for fatigue to dispate?
That is going to depend on how far you over-reach. Some over-reach until they get to a 10% decrease in performance at most (this would be lots of over-reaching). In that case, fatigue will take longer to disipate. However, consistent weeks of training hard will build up fatigue, witch is why people typcally advocate a cut back week or an "unloading week", were you reduce your work load and allow your body to recover, and then you begin to ramp it up again. This may happen over a period of 4 weeks, 3 weeks of ramping up intensity followed by a week of cut back.
what the difference between a resting day and a deloading day?
rest day= do nothing
deloading day= lower intensity and training volume
is HIT the only contributor to fatigue?
intensity, frequency, volume....they can all contribute to fatigue, as can sources outside of the gym....family life, work, money, etc....lack of sleep.
it seems that the teo factor theory identifies fitness and fatigue as two mutually exclusive ideas. if that is the case, in theory you can do a HIT WO and deloading work in the same day. is this right?
It is recognizing fitness and fatigue as the two things that increase when you train. You work out and you gain both fitness and fatigue. The fatgiue is stronger, and masks over the fitness levels....but the fitness levels last twice as long as the fatigue. So, you cut back to let fatigue disipate and the new fitness levels to be seen. They wouldn't happen in the same day. You would have them happen, as I stated before, in blocks of training or, over a week of training (kind of like the Bill Starr 5x5 program).
what is "fatigue" refering to? the physcal wearing of muscle or the exhaustion of the CNS?
Central Fatigue and Peripheral Fatigue. Basically, your body can only handle so much before it starts to turn on you.....kind of like the law of diminishing returns.
also, P-funk, i was trying to search some refs on NCBI, but it seems that site is not good for sports physiology. is there any good database you can recommend?
NCBI?? What are you looking for references on? pubmed.com is all abstracts. If there is a particular paper you are looking for, let me know and I may be able to get it.
thanks