I do about 2 hours of meditation a day. This is useful because it builds a huge capacity for emotional regulation and lets me stand in situations I once would have run from or otherwise sought to avoid, and and I can still clearly see what's going on in these situations. Exercise has its merits (I also walk about 2 hours a day) but they are very different.
As Suzuki Roshi said "Sit Zazen. To live life without sitting Zazen is like winding a watch without setting it: It will run, but it won't tell you the correct time."