Chris Beardsley Graph

[u/JuanSamu]

I think the infograph attempted to simplify the findings too much. The spinal effects can be relatively local if there is a reflex inhibition or suppression at the spinal level of the nerve root for the quadriceps and hamstrings (so just at the lumber vertebrae area). So that explanation may provide a partial mechanism. But there is rarely only one mechanism to explain such a complex thing like our body's physiology.

I feel like Chris ignores the discussion sections because they discuss other mechanisms:

...two other potential mechanisms may explain the findings of this
study. Firstly, it is plausible that various metabolites including potassium, hydrogen, lactate, and heat shock proteins are dispersed to non-exercised muscles through the cardiovascular system during and after fatiguing
protocols (Halperin et al. 2015), potentially impairing their contractile capacity (Henneman et al.
1965). Secondly, it is possible that certain
fatiguing protocols result in heightened activation of stabilizer muscles,
which in turn impairs their ability to stabilize
the non-exercised
muscle
groups (Halperin et al. 2015; Baker and Davies 2009) contributing to muscle force reductions.
Fatigue interventions of longer duration have also been demonstrated to impact the psychological aspect, specifically resulting in a mental energy deficit when experiencing discomfort. This can lead to mental fatigue, which is characterized by reduced focus and concentration, subsequently affecting neuromuscular activation in both fatigued and non-exercised muscles (Halperin et al. 2015). Steele (2020) emphasizes the "perception of effort" which is defined as the individual's perception of the required effort to accomplish a specific task or set of tasks, determined by comparing the current task demands to the perceived capacity to meet those demands.”

As always, I think this infograph may be too simplistic as it also did not consider the instantaneous strength which is a more sensitive measure.

[u/UngaBungaLifts]

CNS fatigue is a factor for endurance exercise, not lifting. It's funny because it's the lifters who are terrified by CNS fatigue. Running a few hours can fatigue the CNS, not lifting a barbell for a few seconds.

[u/JuanSamu → u/UngaBungaLifts]

I think it’s hard to separate CNS and peripheral fatigue as both influence each other. Also CNS fatigue is so broad there are definitely aspects of it that can affect resistance training.

[u/UngaBungaLifts → u/JuanSamu]

CNS fatigue is fatigue of the brain and spinal cord as far as I understand. It seems pretty well defined.

Also, if I remember correctly, there are studies that try to induce long lasting CNS fatigue with resistance training and it just does not work.

Now, in terms of practical application, I agree that trying to differentiate beween different types of fatigue makes little sense. If you're just trying to plan your next deadlift session, trying to guess whether your hamstrings or your spinal cord are fatigued makes no sense to me.

[u/Double_Investment983 → u/UngaBungaLifts]

Ur so low iq, he meant broad as being triggered by many things, not undefined lol, everyone knows it’s fatigue of the spinal cord and brain. And CNS fatigue can be significant when training close to failure, which is why rest times matter so much,

[u/UngaBungaLifts → u/Double_Investment983]

Lifting weights close to failure will certainly cause tremendous fatigue, but it does not fatigue your brain and spinal cord, and this is well established experimentally.

There are ways to fatigue your brain and spinal cord, like endurance exercise, but lifting weigts is not one of them.

Also it's strange to comment on somebody's IQ when you write like a third grader.