The reason why scientist claim running barefoot is better that running on shoes is the foot strike.In bare foot running you land on the front of your feet while running on shoes you land on your heel.
The following images shows the foot strike difference in bare foot running and running in shoes.
Image courtesy of Havard University
The landing on heels is the cause of repetitive stress injuries such as ankle injury, calf injury and Achilles tendinitis.
If you have been looking for the best foot strike or good foot strike to help in your running technique /style just study the above image.