Stress
While there's not a lot of physical, ice-bath-after-practice-type stress for NCAA Rifle, there's a lot of mental stress. You'd think that there's not much involved in hitting a target, but as it turns out, you need to be able to control your muscles, your breathing, and your concentration. Your positioning needs to be perfect, and your can't fatigue your muscles before you shoot.
Yep, rifles are heavy.
If you ask us, though, that sounds like it would be good for stress. After all, a lot of people go to the run range to blow off steam. According to TCU's rifle coach, Karen Monez, "[Rifle] is 90% mental" (source).
And then there's always the usual stress of being a student-athlete and being the best you can be and all that. That's gotta be tough.