Dan Peterson, probably my favourite blogger on sports science, has a recent piece in Science Daily on How Baseball Players Catch Fly Balls. He usually posts on his excellent blog, Sports Are 80 Percent Mental. His post, as usual, is excellent, but I wanted to take issue with the slightest of details (because that’s just how I am): why do novice outfielders often take a step forward when the crack of a bat and the launch of a ball indicates that a fly ball has just been hit in their direction?

As a former and largely inept outfielder for the Ascension Catholic Church ‘Steamrollers,’ 2nd grade and under team (I was more of a junior soccer player), I well remember our coach, Dr. Wickersham, telling us repeatedly, and to little effect, ‘don’t start running forward until you know the pop-up is going to fall in front of you.’ I also clearly remember the sinking feeling when, after failing to heed his advice, a fly ball flew over my head as I charged toward it, ultimately landing almost precisely where I had been standing the instant that ball was hit.

Peterson discusses a recent paper in the journal, Human Movement Science, ‘Catching fly balls: A simulation study of the Chapman strategy,’ by Dimant Kistemakera and colleagues. Kistemakera and his team set out to test the slight variations between the trajectories fielders took when running to intercept a fly ball, and the trajectories predicted by Seville Chapman’s ‘strategy’ of using the acceleration of the ball in one’s vertical field to control whether one was too close or too far from home plate to make the catch.

Continue reading “Catching fly balls: taking a step forward”