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By Hamish Johnston
If you are in the US you are probably looking forward to two things this Thanksgiving Day: turkey and football.
And from the safety of your couch, you might just wonder about the forces involved in a big hit out on the field.
In the video above, you can watch physicist Dan Dahlberg calculating that a particularly hard tackle can accelerate a player at 10 G.
To put that into perspective, heavy braking of a top range sports car will deliver about 1 G and if you drive that car into a brick wall at 30 MPH you would experience 40–50 G.
The player in question is the University of Minnesota’s Eric Decker who was launched into the end zone by an opposing player, but managed to hold on to the ball to score a touchdown.
Although slightly shaken, Decker was back in the game, which was played earlier this year.
Dahlberg – who is normally found in his spintronics lab at the University of Minnesota – is not the first to work out that football players are subject to massive accelerations.
Last month the New Yorker ran an article by Malcolm Gladwell about the potential harm that such hits can cause to the brains of players.
The 10G they calculate here isn’t so much the problem, but the helmet to helmet crash and then the blow Decker had when his head hit the ground. In the New Yorker article you mention, Gladwell reports on research done by Kevin Guskewicz, who runs the Concussion Research Program at the U. of North Carolina. He records the crashes in six sensors in the players’ helmets, measuring directly (not just estimating) the force and location of each blow. He reports blows of up to 98G acceleration, which the brain can well stand. The problem is the cumulative effect of several of these blows.
This is sad to know for those of us who have cherished the game for decades. We all knew it wasn’t harmless, but I guess nobody guessed it could be THAT harmful. It so happens that it can be just as harmful as boxing.
I forgot to add that it’s even sadder for the former players with neurological damage, and especially for those in mental institutions. I’ll never be able to watch the game the same way.
You would think that these players would have serious problems by the time they reach the NFL. I can only imagine what happens to their bodies by the time they are senior citizens.