MLB players are hitting home runs at a steroid-era level and nobody knows why

Through the All-Star break, Major League Baseball players are on pace to hit 5,627 home runs, a level that hasn't been seen since the peak of the Steroid Era, and nobody knows why.

Home runs are up 15% from last year alone and are up a whopping 34% from the 2014 season when 4,186 home runs were hit. MLB is also on pace to hit the most since the 2000 season (5,693), which came two years after the famed Mark McGwire-Sammy Sosa record chase and a year before Barry Bonds hit a record 73 home runs in 2001.

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But what makes the past two seasons unusual is that there is no good explanation.

If you look around, there are players in MLB who are as big as any of the players in the early 2000s. However, MLB's drug-testing policy is as tough as any and home runs had been on a steady decline since it was implemented in 2006.

"I'd like to say that guys aren't cheating," Oakland A's catcher Stephen Vogt recently said to the New York Times. "Everybody's going to speculate - right? - when the home run numbers go up. But we are cleaning up the game, and I hope that's not the reason behind it."

Another possibility is just that the balls are juiced. But MLB told the New York Times that they have done "extensive reviews of the performance of the baseball, and there have been no differences."

There are other theories, including more young, power pitchers who don't have good command and throw more mistake pitches, hitters who are more geared up to hit the ball in the air, and faster pitches which lead to higher exit velocities when good contact is made. There is even a theory that the popularity of the cutter (similar to a slider, with more velocity and less break) has led to more home runs because it is a batting-practice-level fastball when it doesn't break at all.

The real answer probably some combination of all these possibilities.

While we don't know why, we do know that fans are getting the increase in home runs that they crave. But at the same time, strikeouts and walks are way up also. In other words, defenders are being used a lot less and that creates a more boring game. So maybe hitting more home runs wasn't such a great thing after all.