We’re told to do a lot of things softly. Librarians tell us to whisper in the library. Theodore Roosevelt told us, “Speak softly and carry a big stick.” Golfers are told to grip the golf club softly rather than strangle it. Even the hip hop group Fugees sing, “Killing me softly with his song.”
The advice I love the most is to run softly over the ground, like you’re running on eggshells, on ice, or on water. For some reason, runners, coaches, and writers on the subject seem to think that the best way to run is to strike the ground as softly as possible, trying not to crack the eggs. It seems logical, at first thought, that you would want to strike the ground softly, because striking it hard-ly would be bad, causing injuries from all that “pounding.”
But you shouldn’t always do things at first thought. When you dig deeper, into second thoughts and third thoughts and fourth thoughts, you begin to understand things on a different level. Better, quicker running comes from applying more force to the ground so that the ground reaction force applies more force to your foot, propelling you forward with each step. (Remember Isaac Newton’s third law of motion—for every action, there is an equal and opposite reaction).
Running softly over eggs so as not to crack them prevents a runner from optimizing the propulsive force and increase running speed, because running speed is a function of the vertical ground reaction force—the greater the vertical force, the faster the running speed. To create a large ground reaction force, you must strike the ground with a lot of force—hard-ly instead of softly. And running hard-ly would crack a lot of eggs!