The inside of the helmet is designed to ABSORB energy upon impact. Usually on the inside of the helmet there is somehting that lookss like styrofaom. After so many hits on one area it loses its ability to absorb the energy because that area has already taken what it can. As to the mention of "how much does it really protect your head when it hits the ground at 70mph then repetedly hit the ground over the next 100 yards." I would hate to find out it could take seven hits and the last one I needed was the one I alreeady dropped from my waist. I have abouyt three helmets at my house, rule was if I went down on the street or track I replaced it.