bro science or real sience: cnt fatigue

[bartman314]

ok, i get the overtraining point with respect to joints and whatnot. i don't understand, nor have i seen any scientific basis for so-called cnt fatigue as a result of continuous hit or otherwise intense training. i expect there's going to be a bunch of anecdotal experiences that various members have had, but i don't think i've ever experienced cnt fatigue, and i'm just trying to learn more bout it.

i'd appreciate any anecdotal experience one way or the other and especially appreciate any scientific studies looking at cnt.

[MuscleScience]

The concept of Central Fatigue or CNS fatigue was actually a part of my research interest in graduate school. It is a very real and fairly well supported topic in the literature. Journals like Muscle and Nerve, MSSE, JSAC, and Applied Physiology are often places that I see this topic published the most. Hope that helps

[MuscleScience]

Interestingly, it was a concept that powerlifters and Olympic athletes commented on for many many years. Sports or training regimes that mimic sport specific motions with extreme repetition are the test bed, being that you will burn out the nerves ability to keep repeating these motor actions over time. Depletion of the neurotransmitter ACH is often cited as the theoretical mechanism. Muscle wasting diseases such as Duchenne or Becker MD are sometimes thought to point to maybe other causes.

My take is, for what it's worth is :-)

That it's reasonable to assume that just like any other tissue. Nervous tissue especially when subjected to repeated stimulus without proper rest will degrade in function or (fatigue) in response to lack of rest. I think it can be a culmination of factors done a particular motor pathway that is required for say a powerlifter that is training for deadlift. He or she is doing many many repetitive movement either in part or full to produce a smooth, controller and coordinated movement to generate the most power possible to perform the deadlift in competition. This requires a lot ACH to be fired across synaptic gaps. Secondly, calcium and other secondary messengers in the nerve bodies and axons/dendrites would also need to be in a proportional amount to ACH to cause a threshold stimulation of a nerve impulse.

The easiest way to look at it is, that the nervous system is basically an electrical system. And like all electrical systems, power must be supplied constantly In order for the system to produce the required output and outcomes. If power generation is low, you would expect the systems it powers and coordinates to suffer from a decrease in function as well.

[bartman314]

wow! thanks for the input.

since you have a grounding in the fundamentals, my request is to net it out for the (maybe not so) average weightlifter. what would you recommend as a training program (or frequency/duration of rest) for someone using HIT type lifting protocol - lots of hypertrophy rotating around various body parts on a weekly basis?

[MuscleScience]

wow! thanks for the input. since you have a grounding in the fundamentals, my request is to net it out for the (maybe not so) average weightlifter. what would you recommend as a training program (or frequency/duration of rest) for someone using HIT type lifting protocol - lots of hypertrophy rotating around various body parts on a weekly basis?

I feel that 48 hours of rest between "vigorous" bouts of exercise per body part is needed. I think the research is showing this to be a good number for someone between the ages of 18-35.

I use to feel it was 72 hours but I think that maybe it's not the case to prevent overuse injury and such. Obviously someone on gear is going to need less time than the average, because the mechanism by which steroids exert the most effect is by increasing recovery, drastically. I don't know what that number is, but I would say that to prevent ligament and tendon stress, (because these do not heal like muscle tissue) 48 hours is a good safe number at the very least.