Reader Bob Montgomery wrote:
Relatedly, I’m sure you saw this story:
Tobin said the explosion in home runs coincides with a mid-1990s “steroid era” in professional sports. Use dropped to historic levels in 2003 when Major League Baseball instituted steroid testing, the article offers as background.
“A change of only a few percent in the average speed of the batted ball, which can reasonably be expected from steroid use, is enough to increase home run production by at least 50 percent,” Tobin said in a news release.
I haven’t checked the numbers out, but…
Tobin applied a similar, though less extensive, mechanical analysis to pitching and found a smaller impact. He calculated that a 10 percent increase in muscle mass should increase the speed of a thrown ball by about 5 percent, or 4 to 5 miles per hour for a pitcher with a 90-mile-per-hour fastball. That translates to a reduction in earned run average of about 0.5 runs per game.
“That is enough to have a meaningful effect on the success of a pitcher, but it is not nearly as dramatic as the effects on home run production,” Tobin said.
5 mph seems huge to me!
Yeah. It’d be huge. Think about it like this: a pitcher with an 87-mph fastball and good control is at best a marginal major leaguer, most likely grinding out a job at the back of the rotation or in long relief. Throwing 92 with good control, though — that’s a front-end rotation guy.
Similarly, the effects for hitters would be equally huge.
The problem is that anecdotally, we just haven’t seen those kind of increases. The marginal players who’ve been caught in baseball’s testing program saw modest increases – Nate Silver looked into this for “Baseball Between the Numbers” and it was there but not huge. We can look to other suspected or all-but-known players, like Jason Giambi and Barry Bonds, and make some assumptions, but they’re still not that huge.
And for pitchers, there isn’t a lot of evidence to point to any consistent velocity increase. Some pitchers seem to have gained 2-3mph on their fastball, but the benefits are largely in recovery and anti-inflammation, not in raw power.
Under Tobin’s theory, what you could look for in the minors as a determinant of steroid use by pitchers would be descriptions of a pitcher’s velocity through their development. Velocity estimates are unreliable generally, but you would see players stall out in their careers, suddenly return from the off-season throwing +5mph and make the majors. That development path just hasn’t been there, and if pitchers could consistently make that kind of leap, a huge, huge number would all make it as soon as the choice between use & advance and stall was presented to them — and that would be AA & AAA. It’s not there.
Again, anecdotally what we’ve seen is some pitchers who are stalled in the minors see a much more modest increase in velocity.
Beyond that, I think the attribution of the rise in home runs neglects a lot of the other, larger things going on that also drove the home run rate in those years.