same thing with muscle so i heard
naturally limited to 33% because going higher damages your muscles like tearing it or liquifying it (unless you're pumped up on adrenaline)
iirc the average human uses 20-30% of the muscle fibers in their muscles at almost all times, except when adrenaline is released during stressful high-performance tasks or emergencies, under which circumstances around 65% of the muscle fibers can be used
trained athletes may not be using much more percentage of their muscle fibers than an average person (depends on how they train), but they usually have a higher max-usage ceiling of around 80% all the way up to 100% (at which point you could really traumatize your muscles), once again, depending on training
you can increase the percentage of muscle fiber you use at all times by focusing on neural adaptation, or you can increase your strength at any given percentage by focusing on hypertrophy. which is easier to make gains in is dependent on genetics for the most part, but regardless, whenever you train you make gains in both fields no matter how small they may be
imo far more interesting than this brain % usage crap. different parts of the brain control different aspects of your body, with only one of those parts dedicated to cognitive thought. now if you want to use 100% of your cognitive potential, read a book on quantum physics or mathematical theories. if you can't understand a concept on your own no matter how hard you focus and think on it, congrats, you've hit your ceiling
