What does the science say about the grass VS. turf debate in sports?

Which playing surface is safer for athletes: natural grass or artificial turf? The question is important not just in football, but also for soccer, recreational sports and high school and college athletics -- anywhere athletes make sudden shifts in direction that can twist joints and tear ligaments.

What does the science say about the grass VS. turf debate in sports?
Which playing surface is safer for athletes: natural grass or artificial turf? The question is important not just in football, but also for soccer, recreational sports and high school and college athletics -- anywhere athletes make sudden shifts in direction that can twist joints and tear ligaments.