RE: running body frame
I used to run 35 to 50 miles per week. I don't believe how often you can run has anything to do with how big you are or how large your bones are. If you run wisely, you can certainly do it daily. My biomechanics are such that running, indeed, daily activity, might not always be best for me. I plan rest days, particularly after high intensity or high impact activities. I have high arched feet and have a number of injuries, including a collasped arch. Fortunately, the running shoe industry has a shoe for every type runner and using the right shoe can circumvent many problems. When I used to run to days in a row, I alternated shoes to minimize wear and tear. I used to be very serious about running!
My sister has a more neutral gait and runs daily with no problem.
I have read of people who have run daily for years and years. No days off!
As for stretching, everyone should but people are flexible to varying degrees and it could be your friend has more natural flexibility and can get away without stretching. It may catch up with her. If you feel you should stretch before you run, it is important to warm up first by doing rhythmic movements. Otherwise, you risk injury. It is probably more important to stretch after you run when your mucles have shortened and tightened as a result of the rhythmic contraction during your exercise. They are warm after exercise and it's the perfect time to stretch and lengthen them.
It's really a matter of preference. Listen to your body. It will tell you if you can run daily or if you should alternate days. There is also the "point of diminishing returns". Once you go over a certain amount of running or any activity, it is no longer beneficial; no gains are made and the risk of injury increases. Exercise addicts experience this. What's optimal for you? I find 5-6 days of cardio is great but rest, particularly after an intense workout is also key!
Good luck!
BOBBI
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