Now scientists have used the skeleton of a T. rex to model the biomechanics of the animal’s stride. Intagliata: Pasha van Bijlert is a movement scientist at Vrije University in Amsterdam. Van Bijlert: And to do that, we found a fossilized trackway of a smaller tyrannosaur. Intagliata: Multiply step length by step rhythm, and you get a speed of 1.28 meters per second, or about 2.9 miles per hour. Van Bijlert: I guess we should be glad that there’s a lot of time between us and T. rex.