Well, cross country training starting last June was pretty varied day to day. Tempo runs on the track, springs on the track, running on trails and side walks, running through fields, running through fields bare foot, hills and lots of core conditioning. He wasn't very big on stretching. Their cool down was a 2 mile run. His coach was a track/field and cross country runner at Auburn. Not shabby. And he is young and has produced in his 5 years at the school a pretty successful CC team. We buy running shoes on a regular basis so he always has good shoes. So far, other than some sore calves occasionally and possibly sore hamstring, he's not had any complaints. But you know . . . you think about the future.
Mom, is he running cross country in cross country terrain, or on hard pavement, or on a track? Is he used to walking around and playing barefoot, or has he always worn heavily padded shoes? Does he also work on strength -- it sounds like it would be hard to cross-train with so many running days. But true cross country, and I know they don't do this anymore in a lot of places, used to be a lot of running on dirt and grass -- thus the name cross country. In the end, nobody knows how strong their body is until it breaks. If he keeps this up, it could be knees, hips, and plantar fasciitis, ACL, all sorts of things, but cross country is probably less stressful than basketball or football or soccer. But it could be those things from doing squats, too. Vigorous exercise comes with injury. Age comes with deterioration. Distance runners, especially marathoners, have some correlation with increased heart problems as they age. I don't think you can protect him, if it isn't this, if he's into athletic activity, it will be something else. The one thing he can do is work on foot strength, which is why I asked about shoes and surface he's running on. I know a runner, he's the head of the local running club, he's been running for years, he's old, and he's been running on hard surfaces, he ran everywhere -- I mean, the guy even ran to work. Never saw him out of running clothes even though he's a very successful software programmer. Don't think he ever had an injury. You just can't tell. Don't think he started that young, though.