This makes sense to me. I hear this on HN all the time and don't doubt that exercise does provide mental benefits to most people.

However, anecdotally, exercise (and getting a good night's sleep) has had no noticeable impact on my focus and/or productivity.

Is there anyone else that doesn't feel like exercise doesn't do anything? Or is it because I'm not exercising long enough or with enough intensity to make a difference?

At one point I went from being completely sedentary for about 6 years to spending about 3 months running 2-3 miles a day on an elliptical about 4 times a week with decent consistency. After a while, it did become easier to run further and for a longer period of time (from 2 miles to 3 miles), but I didn't notice any of the mental benefits that seem to be attributed to exercise. I still felt a general "brain haze" and sluggishness that I had assumed was a direct result of being out of shape. I've since gone to exercising on and off for another 3 months before going back to essentially being completely sedentary for several months and nothing about my mental state seems to have changed.

That being said, I do plan on exercising again to ideally get healthy in the longer term regardless of whether or not I get any immediate mental benefit. And I also plan on recording things more diligently to determine if there actually is a result for me.

The elliptical machine barely counts as exercise ;)

I have found that hard exercise, requiring mental fortitude to push through is what really helps. Sprints, power lifting, and distance running wear you down physically and mentally. IMO, continually pushing past the mental 'this is hard I want to stop' phase translates to increased concentration and acuity in other types of mental tasks.

I personally find that team sports help much more than individual sports. It's the only thing that motivates me to push myself beyond my mental limit to my physical limit. Basketball is my all time favorite sport, and I'd play for 3 hours a day if I could, but I've started playing soccer again and I think it's probably just as beneficial.

Didn't see your comment when I posted mine, but I feel much the same.

It's just far more interesting and satisfying. Telling someone to walk on a treadmill to help their focus is like telling them to watch paint dry. But team sports are dynamic, which I feel suits people such as myself, who have a hard time staying focused on one thing.

What sucks about team sports is that few people who play at a high level care to play with someone who can't keep up. So you need to do something to get to a certain level at least. I play soccer and basketball weekly, and I think the extra workouts do help with my performance on the field and court.

Those have never kept me engaged.

What does is playing a sport. Playing pick up soccer gives me a far better workout than lifting heavy objects and grinding on a treadmill, even at high intensity levels.

It's easy to say do these exercises, but to people who have minds that jump around a lot, mundane, boring exercises are not enticing.

I wonder if you just weren't pushing yourself hard enough. Ellipticals are fine, especially if you have bad knees, but they're not going to push your body as hard as other stuff. I'm working out these days, and after a couple of months, I notice I feel better. I admit I don't know how to describe it, but I feel healthier and stronger, and that seems to have some sort of effect on me. I don't know if I would have gotten there though if I did ellipticals instead of pushing myself with a coach at my gym, and going through a period of pain that I felt great to get to the other side of, just the feeling of not giving up. It may also be a placebo effect or increased self esteem or something else, but there's something there. Also, I'm totally not an expert on the subject. But I think there is something there, based on my own experience.

Try climbing. It's a physical and mental workout that is matched by few other activities.