*Get Enough Complete Days Off The very first thing that you must make sure you're doing is getting enough total days off per week.
Those who train too often in the gym are going to be at the highest risk of CNS overtraining because each time you perform a weight lifting activity, you are going to be stressing out the CNS.
Do this too often throughout the week and you will have some serious problems after a couple weeks' time.
If you can get one day off between each of the weight lifting workouts to gain weight you perform, that's the best case scenario.
If not, aim for at least two days off per week at minimum.
*Don't Take Every Set To Failure Next, make sure that you aren't constantly training to failure either.
If you take each and every set to failure, this is going to place far more stress on the CNS than it can handle.
Back off once in a while.
While you do need to take some sets to failure every so often so that you can gain muscle effectively, you don't need to take every single set to failure.
That's just doing a little more than the body can handle.
*Sleep Enough Moving along, sleep is also critical to success with avoiding CNS overtraining as you gain muscle.
If you aren't sleeping enough, you won't be giving your body the high-recovery time it needs and will definitely be feeling it the next day.
Aim for no less than seven hours - if not eight or nine if you can get it each night while you're trying to gain weight quickly.
This will make a profound difference in your results.
*Stress Less Finally, the last quick point to know as you go about your quest of learning how to gain muscle and avoid CNS overtraining is to make sure that you aren't stressing yourself out too much.
High levels of stress are also very taxing on the central nervous system, so your mission needs to be to keep your stress as low as you possibly can.
Practice stress reducing techniques if you have to - just do whatever it takes to avoid being too stressed out.