Annie Repping at The Fittest Games
Every Tuesday night we do something called "Night Ops." It's basically training at night in Austere locations around town. Lately I have been doing it in a weighted vest. The additional abuse on my knees, ankles, and feet was surprising. The vest is only about 25lbs and the mileage is always under 3 and usually on soft surfaces.
It made me think about all the heavier runners I see logging in 20+ miles a week and the amount of impact they are putting on their joints.
The interesting thing about running is that if you want to get significantly faster one of the best things you can do is get lighter. I run once a week now and its usually interval based sprinting. While in Fort Benning I ran 4-5x a week and struggled to run a 13 min 2 mile. I can do it now while holding a conversation. Am I a more conditioned runner? I don't think so. I think it's the 20lbs of unnecessary muscle mass I was carrying.
If you are looking to get faster you need to evaluate if you are carrying too much weight, this can be body fat or excessive muscles mass. If so lose it. Your times will be faster and your joints will thank you.