If you RUN 60 minutes a day that could easily lead to overuse injuries but it wont cause overtraining (loss of strength, loss of muscle mass, etc)
Yea, Scooby is right. Your muscles can take it but you will risk overuse injuries to your joints or bones, or it may cause shin splints. I was running a lot just before winter, after a while my ankles felt stiff, eventually I was experiencing mild pain after each run. I iced and stretched after each run, the pain got worse. At this point I started biking and found that for me i need to bike for long cardio/endurance workouts. My ankle pain took about a week to heal at the age of 23 may take longer if your older, I put a halt to running and biked for that time and felt great. I wanted to share that information just to give you an idea of what "could" happen not what
will happen. My point is at the end of your runs really focus on how your lower body feels, and look for warning signs, like stiffness in the joint areas. This is really where everyone is different. I know a guy that swears biking kills his knee, and another guy who says he has to bike or his knee will hurt. So just look out for warning signs and always access the situation, before and after a run/bike. Take in account how well you do on hills, I know I have to limit my down hill time on every run, others have to limit up hill running. Final tip get a good pare of shoes.
