I've been taking jumping lessons for couple months. Lots of fun and GREAT instructor. But I almost always have problems with back muscles for couple days after the lesson (usually feel tense in middle/lower of the back). Is it something common? May be some exercises to prevent that happening in 1st place?
Now, I try to ride every day (flat mostly), and I also take dressage lessons (that often are even more intense than jumping). But I don't have back issues after those.