On the contrary, I always liked sports that compensate for mental work. Also, physical activity can be healthy and, as they say, mens sana in corpore sano... (For example, running is said to be healthy for the brain and I found it very useful for forcing my brain to pause. One problem is that in the long term running destroys your knees, so after two marathons I will reduce long-distance running in the future.)
This has some tradition, for example Alan Turing (maybe the greatest computer scientist of all time?) and Bobby Fischer (maybe the best chess player of all time?) did a lot of sports and Fischer said that he wanted to keep in shape for chess explaining that one needs a lot of stamina for playing four to five hours.
So, I think rationalist sports should support the more important mental activities, e.g. by improving health.
Does running destroy everyone's knees? My impression is that it's risky for knees, but not everyone takes damage.
I remember the existence of an article in Runner's World long ago where they interviewed runners who hadn't taken damage.
The comments to Running with the Whole Body have some people who say the Feldenkrais work in the book protected their knees.
This post is a bit of an experiment; Most of the time, Discussion post lay out an idea and this idea then get commented upon. This post, on the other hand, will be purely about discussion on a topic. If this works out well, I'll might post more of these in the future.
On to the meat of this post:
I got this idea from a reddit post on /r/LessWrong.
To quote:
So have at it.
I only ask for one thing and that is to hold off on proposing solutions for 24 hours before giving suggestions for actual sports. In the first 24 hours, please discuss what makes current sports unappealing to rationalists and what aspects a sports designed for aspiring rationalists should have.
Edit: The 24-hour window has closed and solutions and suggestions can now be given.