Runners are sometimes told to avoid the "heel strike" to prevent injuries, but experts say changing to a fore-foot landing can cause different problems.
In a heel strike, runners land on their heels instead of on the middle of the feet. Avoiding a heel strike and landing on the front of the feet has been billed as a way to prevent injuries because that's how humans "naturally" run.
"The idea that heel strike is dangerous and fore-foot landing is less dangerous is very well distributed now, and it's wrong," said biomechanist Benno Nigg of the University of Calgary's Human Performance Laboratory.
The original advice to avoid heel strikes was based on measurements of the external forces when different areas of the foot hit the ground first. But Nigg explains those measurements don't adequately take into consideration the forces that matter for injuries: internal forces, such as on the ankle, Achilles tendon and lower leg structures.
Watch CBC-TV's Kim Brunhuber get a treadmill explanation from Ryan Robinson of the Pedorthic Association of Canada to see a safer alternative.