The most fun game in the whole world is the one where you pick an object — a pebble, a pinecone, a wadded-up piece of paper — and throw it at another object — a stump, a telephone pole, a garbage can. It's tough to get just right, it takes practice, and when you get the speed and accuracy to sync up in just the right way, it's unbelievably rewarding.
Maybe the reason throwing things at other things is so satisfying is because it's something only humans do consistently well. Other primates can throw things, but since they lack our special brand of motor control, they're not wonderful at targeting. A new study published in the journal Royal Society Open Science looks at the physics of throwing, and how we humans developed our virtuosic talent for both coordinating speed and accuracy in a throw. The research team also investigated why different types of tosses are best in different situations.
Since speed and accuracy are both key elements in a throw, the researchers looked at the costs and benefits of choosing speed over accuracy, and vice versa. For instance, accuracy is usually compromised when you throw something very quickly: It's difficult to release a ball at precisely the right millisecond, and fast throws tend to travel in pretty straight lines, so even a tiny error in the release is exaggerated in the outcome. So, if it's accuracy you're going for, a nice, slow toss will be more forgiving.
And in some situations, accuracy takes precedence over speed — like in basketball, for instance — but early humans developed their throwing skills trying to hit woolly mammoths with spears and rocks and stuff. In that game, you're going to want both.
"You don't just want to be fast or just accurate, you want to be fast and accurate, and this work tells us that this is particularly challenging," says co-author Dr. Madhusudhan Venkadesan at the Yale School of Engineering & Applied Science, in a press release. "The faster you are, the less accurate you are, so how can we be both? That's a question we're pursuing."
So, how is this holy grail of power and precision achieved? Technique, of course. Whether you throw overhand or underhand depends a lot on the size, shape and height of your target. If you're going for speed, an overhand throw is going to be your best bet most of the time, unless, of course, you're playing cricket: Striking down a cricket wicket is best done with a very fast underhand pitch. The best dart players know an overhand throw is best, releasing the dart at between 17 to 37 degrees before the arm completely straightens. If a trash can is more than three arms' lengths away and lower than your shoulder, your best bet is to overhand that crumpled-up wad of paper.
Interestingly, most of us intuit the optimal occasion-appropriate throwing technique for a given situation, probably due to constant practice.