I have read it is somewhere at 12%...
What is the science behind it if true and what is the truth if it is not true?
No there is no set optimum that applies to everyone on planet earth
Obviously there are human limitaiins however
I watched a documentary the other day with ... A guy who could swim under Water for 9 mins ...
A woman who since childhood has been living on 3 packets of crisps a day and looks quite normal.
A man who sswam in the north pole glaciers
... So you see there are anomalies out there.
Apply that to your strength question
The majority of people who come on here shouting bullshit or drugs on others achievements are just
A. Narrow minded jealous if I didn't make x gains no one can
B. Failures
C. Ignorant