Professor Norman Drummond, who is behind the Columba 1400 programme, said: "I don't think it's right that headteachers should be working so incredibly hard that they go home, have a little chat with their children, and then work from 9 till midnight on a regular basis."
He added: "We've got to find a way to enable this to be the profession that allows people to breathe, to feel confident, to feel that it's not just a burden all the time, that there's not just another form to fill in, there's not just something that comes down from a great, great height."
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Professor Drummond made his comments at the recent annual conference of School Leaders Scotland (SLS) – which represents secondary teachers in promoted posts – held in St Andrews.
He also argued that the perception of teaching had to change so that more people were attracted to what should be a singularly fulfilling job.
Professor Drummond said: "There is no more important profession in the world...than that of looking after other people's children, seeing the best in them, enabling to be all that they can be."
He added: "It's a way of life, it's not a job. We need to put that message out there to more and more young people, who would love to come into teaching if it wasn't so perceived as just being a job where get measured left, right and centre."
He suggested that education was like other professional sectors in having got its priorities wrong in recent times.
"I wonder if we've been so busy, in all the professions, of valuing targets that the time now in our common humanity is to target values," he said.
He added: "I think we need to speak truth to power, and to actually say to people, 'This isn't good for my school. This isn't working.'"
Professor Drummond saw "a real danger in life that things get out of balance" and told the secondary school leaders at the conference that they should always have "something to look forward to [and] give yourself a treat". They should prioritise family time when emails will not be checked, allowing space to "really regenerate" – and the "black [work] briefcase shouldn't terrorise your weekend".
He advised heads to make sure they have a "trusted other to whom you can go at any time" if something "hits the fan".
Professor Drummond also called for "more praise and encouragement in daily life", particularly in Scotland where "no bad" often seemed the greatest compliment someone can get.
"The oxygen of the soul is encouragement," he said.
Professor Drummond also said that he regularly encountered leaders who suffered from "impostor syndrome", and that headteachers should realise this was a common feeling and not let it get in the way of doing their best.