It will be a break just because it needs a conscious effort. But presumably if you build a routine, a habit, it will work by itself. You will be able to continue thinking your deep thoughts, while your body will transpose itself to a treadmill, do some movements there and then transpose itself back.

The tricky part is how to build an automatic routine and how to trigger it every 20 minutes without breaking the concentration.

    0 min: start working
    
    10 min: refactored a few things, get a glas of water, look out of the window
    
    40 min: started working on a particular though problem, somewhat stuck, get up and stretch a little while thinking
    
    60 min: found a good solution to though problem, keep it in your head, goto kitchen get another glas of water
    
    120 min: after an hour of uninterrupted flow the though problem is solved, stand up, get a cup of tea, think about whether it is really adequately solved
    
    etc.   

I program myself and found a change of perspective and bodily motion in the right spots can help concentration, not break it, especially in the long run. Don't let the perfect be the enemy of the good. If you have a variable height desk, you can also alternate between sitting and standing, which can also help as you now have at least two different resting poses with slightly different kinds of strain.

And drinking more coffee helps a lot. You have to get up to make the coffee, then to pee it out. The caffiene in sufficuent quantity makes it hard to sit still. You talk faster so people think you're more productive too.

> -keep it in your head,

+write it down

Sounds like an argument against rto to me...

I approximately never need to focus to the level that standing up and pacing a bit would evict state, let alone need to focus like that for for over a half hour at a time.

And I think if I was focusing like that, I'd probably just forget to take a break.

Basically - movement isn't free

That's an interesting lifestyle choice, but don't be shocked if others refuse to follow along.

Try not to involve your legs in any thought process. With enough training you should be able to take your concentration into the kitchen, the bathroom, the shower, etc.

    > That's at least halving my productivity.

Now, admittedly, standing up for a stretch does not break my flow. Neither does walking around my house or doing the dishes. Generally it's talking to another human that'll do it every time. Light exercise should be more than possible to work into your day once it becomes familiar and routine.

schedule a meeting once a week and we'll catch up. if you're stuck, send me an email and I'll get back to you when it won't interrupt my own work.

https://content.wolfram.com/sites/43/2019/02/05-treadmill-r2...

https://content.wolfram.com/sites/43/2019/02/07-popcorn-rig1...

Whenever I do not type at the keyboard, but I think about what I should do, I stand up and walk around.

I actually think much better about the problem that I have to solve while walking than when sitting.

Like many people throughout time I do much of my best thinking while walking or exercising. To the point that to crack a hard problem is often easiest if I get up and go for a stroll.

This is even easier given that there is seldom only one problem to crack. The combination of switching tasks and moving about, getting the blood pumping, seeing new things, and breaking pattern is an incredibly reliable way to generate good ideas, solutions and approaches.