Working all hours is for super-heroes
He managed to keep 27 men stranded for two years 1,200 miles from civilisation both healthy and happy, said Mr Munby.
Even more popular with his audience was the example of footballer Alan Shearer, still a top goal-scorer well into his thirties by dint of shifting from pace to positional play.
"Many of you as school leaders are not as young as you used to be," said Mr Munby. "So, like Alan Shearer, we have to adjust our game. We don't have to be a super-hero leader, working all hours."