As human beings we are made for running and travelling long distances. Some animals might be a lot faster when sprinting over short distances, but no other living being on earth is capable to run for hours in a constant speed like we can. The bodies of animals would overheat and finally collapse. As they don't have the transpiration system we have to already cool our bodies down sufficiently while running they have to stop after moving fast for a while. This is the advantage our ancestors successfully used to survive as they could hunt down an animal until it was too weak to go on. If you are an atheist you can say that evolution has made our bodies perfect for running. If you believe in god you can say that god has created for us a body perfect for running. However, the truth is that we are born to run and to use our legs.
In today's society we live contrary to our inner nature. We use cars to drive to work. At work we spend most time of the day in a sitting position. We use our car to go shopping, where we buy food high in calories and nutritional values which our ancestors could only acquire after having moved over long distances or having worked hard for. It's really no surprise a lot of people have weight problems or suffer from civilizational deseases. For a very long period in history humans had to regularly run fast to survive; and running kept their bodies fit and healthy. They didn't need the newest expensive running shoes to pad their feet or to protect their joints. They ran in a natural way and their joints, bones and muscles were used to this and naturally strengthened by this constant exercise. This is something you cannot achieve with high-tech running shoes.
Don't act against your nature. Go out and start moving the healthy way by natural running where you cannot push and easy pushing where you don't have to run!
To all joggers out there: Don't be afraid of asphalt or concrete. Just get yourself a longboard and add even more fun to your exercise routine. Pushing a longboard can be a cardio-workout and with ChiPushing you have a technique to move fast on hard ground with only minimal impact on your joints.