Grunting

Breaking news, scientists discover grunting.

Well, something like that anyway. For many years (at least as far back as Jimmy Connors) there has been debate in the tennis world about players who grunt and those who are distracted by it and want to forbid it.

It was shown recently that grunting does in fact have a positive effect on performance. link

To summarize, various study participants had a 1% - 5% performance boost if they grunted during weighlifting. And some rather colorful speculation as to why this works (or doesn't):
1. "Grunting quiets inhibitory nerves cells in the spinal cord. Those cells would normally impede the ability of muscles to contract and generate force."
2. "It's a psychological thing. But psychology is very important in sports in general -- if you think you can, it raises the possibility that you can."
3. "Some people grunt to give others the impression that [the grunters] are doing a lot of work. It's just like flexing and strutting, trying to attract attention."
4. "They're not breathing properly. In order to grunt, they have to hold their breath and exhale forcefully."

I have a confession. I used to not be a grunter, but I found one day that I had become one. I play soccer with college students half my age, and when I
need a burst of acceleration, I grunt loudly and instinctively. Once I realized I was doing that, the reason became clear, at least to me. I needed to force blood/oxygen into my leg muscles. The grunt does this by increasing blood pressure.

Now if only I can figure out why I yawn...

Innocence

I assume you're familiar with the Innocence Project. That's the one where wrongly convicted prisoners are freed after many years because new DNA techniques become available. Many of these people were freed from death row. This, rightfully, makes a lot of people celebrate. But why does noone talk about the elephant in the room.

Let U be the number of cases where DNA evidence does not become available.
Let D be the number of cases where DNA evidence becomes available.
Let E be the number of cases among D where the new DNA evidence exonerates the suspect.

Then we might expect that U * E / D prisoners will serve their full sentences for crimes they didn't commit. If we apply this reasoning to the death penalty, we will find a virtual statistical certainty that we have executed some number of innocent people. We just don't know which ones they are.

In this way, the emergence of a revolutionary type of evidence provides a statistical window onto the health of the justice system in general. Unfortunately, it is a temporary window. 20 years from now, there will be no more cases where there is unanalyzed DNA evidence. And I would argue that a technique this revolutionary is a singular event, and will not be repeated anytime soon. And if the elephant continues to be ignored and the present system is not fixed, then there will be no longer be an easy way to demonstrate it is broken.