Can you start a business without working yourself to death?

I grew up hearing about entrepreneurs that work 70-80 hour weeks in the early years of their business. Recently I've been reading books like "Buy Back Your Time", and "10X is easier than 2X", that talk about working more normal hours (40-50), and spend those hours on the highest impact work, while finding people to work on the tasks that you do not enjoy and that they are better at.

I have also heard that productivity per hour goes down the more hours you work after a certain point, because you end up making more mistakes and having to do re-work when you're tired. I have seen that in my own work in a corporate role.

Can any entrepreneurs out there attest to if it is possible to have a more balanced approach to time spent on the business, or should I expect to grind the first several years doing consistently intense hours?