I worked with a guy that did that. We have no showers at my office (like most offices), he quite after a couple of weeks when people started to complain that they didn't like the sweaty B.O. mess coming in with them in the mornings.
Its unfortunate there wasn't a better solution for your colleague. The half hour ride in the morning isn't at a hard enough pace to make me a sweaty mess, though if it did, luckily, we have showers (along with a gym) at the office.