Strikeouts are on the rise in the MLB. Why? The prevailing thought is that hitters have embraced the launch angle revolution and it is causing holes in many hitter’s swings. There may be some truth to that as the ability to get the low pitch in the air has definitely taken a priority for many hitters. Many hitters are employing a vertical bat angle swing which makes getting to the up fastball a little tougher. Couple that with a generally higher strike zone we are seeing and hitters now have to protect against the up fastball like never before. But there’s another factor and it’s a big one.
Pitchers today just plain throw harder and have sharper breaking stuff. The number of pitchers who throw over 95 mph have grown 5x from 2008. That’s a huge increase. With the implementation of weighted ball, long toss and strength training programs, pitchers are reaching velocity ranges never before seen. Can you imagine having 5-6 Nolan Ryans or Bob Gibsons on your staff? From a Velo/Stuff perspective, that is the baseball environment today. It seems as though everyone is throwing 95-98 mph today with some reaching 100+ mph. This has definitely had an effect on the hitter’s ability to catch up to fastballs up in the zone. But this would have happened regardless of swing mechanics.
The underrated factor is that breaking balls are better now too. With increased velocity comes increased spin rates. In general, a pitcher’s Bauer Units (Spin/Velocity) will increase on an upward sloped line as velocity increases. This leads to harder and sharper breaking balls in general. So now hitters have to worry about breaking balls going further down the line (tunneling) before breaking. This is a huge benefit for a pitcher and must be taken into account when discussing strikeout rates.
So what’s the main contributor toward the increase in strikeouts? It’s a combination of both new hitting mechanics and better velocity. What percentage is debatable but, in my opinion, the increased velocity is 80% of the problem for hitters. Reaction time is reduced, pitch recognition is tougher and the human body can only adjust so much before you have to start guessing based on count, situation, etc. Once a hitter’s reaction time goes below .395 seconds, he is put into a pick or choose mode unless he can effectively create time by getting a running start into his swing or committing to a single pitch.