Do heavier loads cause greater CNS fatigue than lighter loads ?

Do heavier loads cause greater CNS fatigue than lighter loads ?⭕️

It may feel intuitive to assume so, in fact it’s quite common to think that “heavy loads” “fry your CNS!”

But in reality it’s not much about the *weight* it self: in fact, it’s more about the duration of these hard, muscular contractions.

CNS Fatigue is something measurable, and it can be defined as the inability to produce force by a given muscle, due to a reduction in neural drice force, which can again be caused by a multitude of factors.

If it lasts for several days, it’s actually more related to peripheral factors, such as muscle fiber damage, following hard, long-lasting contractions, which are more likely to occur in light-weight “resistance type” training.

Why is fatigue important to monitor?

Excessive fatigue accumulation can hinder progress, especially if the program is hypertrophy-oriented, because not being able to tap into high-threshold motor units means simply not making the training as effective as it should be

(hint: Type II fibers are the ones that grow the most with strength training!)

For this reason, keeping the loads on the heavier side (for most exercises) can help us maximize the efficiency of out training programs, while accumulating less fatigue.

As always, working within optimal training volume guidelines will be paramount when training for hypertrophy!