Okay, but we did evolve to run on dirt and rock, neither of which are particularly soft. Equally important, studies indicate that impact does not decrease when

Okay, but we did evolve to run on dirt and rock, neither of which are particularly soft. Equally important, studies indicate that impact does not decrease when running on softer surfaces. Runner instinctively step harder on soft surfaces and more softer on hard surfaces, to get the same feedback from their feet and legs.