Rock climbers have known this for a while. Climbing long sustained routes builds endurance, but not strength. Short strenuous bouldering problems build both endurance and strength.
Personally I think climbing is the perfect hacker sport. Climbing nearly always favors forethought and elegance over brute force. Bouldering problems are so named because they ideally require several iterations to find the optimal path. Sometime a single moment of insight is all it takes for a problem to go from very hard to trivial (in the hacker sense of the word); yet there is always something new to learn, even from trivial problems.
Personally I think climbing is the perfect hacker sport. Climbing nearly always favors forethought and elegance over brute force. Bouldering problems are so named because they ideally require several iterations to find the optimal path. Sometime a single moment of insight is all it takes for a problem to go from very hard to trivial (in the hacker sense of the word); yet there is always something new to learn, even from trivial problems.