>>76463336
This desu

Sub 20 is doable with any body type that is not obese
Sub 18 you need to be a bit leaner but still doable on a cut
Sub 15 you have to be running every day and much leaner, but don't have to go auschwitz mode - see Nick Bester in picrel, a 14:30 runner
Sub 14 i.e. elite you need to be a skellington