> Do you take brakes and walk around?

That's a novel approach to exercising.

I'd second this comment. I found lack of movement to be the problem for me. After several hours in front of the computer coding, browsing, whatever, I'd find myself feeling zombie-like and brain-fogged. I got inspired by the Walk and Code blog post[1] and bought a walking treadmill for work. Bye-bye zombie feeling.

I work in an open office environment, so I needed one that was quiet. I bought the Rebel Treadmill 1000 and it's so quiet me and my office mates can hardly hear it over the sound of the HVAC system. Not affiliated with the company that makes them, but I heartily recommend their treadmill if you get in the market for one.

[1] https://8thlight.com/blog/doug-bradbury/2010/02/25/walk-and-...