I understand why you'd address this to entrepeneurs given the audience around here, but really, is there anyone to whom this advice _doesn't_ apply? Sure, if you're a textbook entrepeneur you're working hard and might overlook other things. Same if you're working three jobs to make ends meet, or if you're studying all hours, or looking after your family. The advice has common validity.
Your strategy won't work for everyone, or even most people, because "just do it", whilst very compelling short term, tends to lose effectiveness over time. Instead seek out something that you really enjoy, that coincidentally provides great exercise, removing any problem about motivation and long term commitment. If hanging at the gymn really is your thing that's great, but if not, don't beat yourself up, get into something else instead, cycling, karate, trapeze, dance, roller-derby, yoga, there are lots of alternatives, main thing is to make it fun then you won't need the "I must do this" self-discipline every day, you'll go out of your way to do it.
And as others say, explore creative and cultural activities too. Your mind does not thrive on pure coding and hustling alone, it needs its own free-form exercise too.
Your strategy won't work for everyone, or even most people, because "just do it", whilst very compelling short term, tends to lose effectiveness over time. Instead seek out something that you really enjoy, that coincidentally provides great exercise, removing any problem about motivation and long term commitment. If hanging at the gymn really is your thing that's great, but if not, don't beat yourself up, get into something else instead, cycling, karate, trapeze, dance, roller-derby, yoga, there are lots of alternatives, main thing is to make it fun then you won't need the "I must do this" self-discipline every day, you'll go out of your way to do it.
And as others say, explore creative and cultural activities too. Your mind does not thrive on pure coding and hustling alone, it needs its own free-form exercise too.