Bat Speed vs. Exit Speed?

[Bonesaw]

Long story short: I think players using a 33 drop 10 can use .1 for the q of a perfectly struck ball.

Long story not short: The q in the equation battedball speed= q*pitch speed + (1+q)*batspeed is the "collision factor" It is based off of the BBCOR(Bat and ball COR's) and a "kinematic factor "k". K is based off of the mass of the ball and the "effective mass" of the bat (it's MOI). The MOI, is very important in determining q,. so it will be impossible to have one all encompassing Q for all fastpitch players since so many different size bats are used.

For example, one site (which I can't find again to link) said that a negative q is possible with super light bats. This would mean exit speed is lower than bat speed.

On the other hand, if a player uses an end-loaded 34-26 then .1 might be a little low.

It is just an estimate anyways.

Here is where all the info came from:

After reading the 2 articles listed at the end, I thought that a q of .1 or .11 for a "standard" fastpitch bat might be reasonable(explained below). And then I found these 2 videos of Lauren Chamberlain hitting off a tee for a blast motion commercial. I believe they are the same swing(i'd put money on it!). In the one they show a swing speed of 68.2. In the other one they use "blast vision" which measures the ballspeed at 75. Plug 68.2 into the equation with .1 as the q and you get 75.02.

I probably wouldn't have posted anything if I hadn't found these or any other data to back up the .1 number.




Let's say she squared that 68.2 swing up on a pitch going 60 at the plate. Her exit velocity would be esitmated at 81. Is this reasonable?


For anyone interested in where the pre-video "guesses" came from, the .1 or .11 was based on the article from WSU. The WSU article shows that a standard(max allowed hotness) ASA slow pitch bat would produce a exit velocity of 74 with a swingspeed of 60 and a pitch speed of 60 mph. q = .12 for that bat. I think the standard slowpitch is 34 drop 8 (and most likely end loaded?) which would make it have a substantially higher MOI than a typical fastpitch bat. They listed the MOI at 9000in2.

However, fastpitch bats are allowed to be a little hotter (have slightly higher COR). And I believe the ASA is tested with a .44 COR ball. So a .47 ball would add a little to q as well(higher COR ball). So .1 or .11 seemed ok. And then the Chamberlain videos somewhat validated it.

Here are the two articles

Bat Performance Measures | Sports Science Laboratory | Washington State University

ssl.wsu.edu

Explaining the BBS standard for ASA softball

 

[Westwind]

Nice to read your detail.
You mention her swing plane improved.
Without seeing how exactly...
Would equate that to better impact!

Could you see visually the ball exiting faster/explosive?

Did you also notice a better trajectory of the ball? Its path?
More consistancy?

Had to think about this a little.

I‘m just not sure that the one metric, by itself, is critical. It’s worth working on but I keep hearing that you shouldn’t chase numbers or get too wrapped up in a single metric. It seems like the current thinking by hitting coaches is that good hitters have some metrics that are good but most won’t have all good metrics all of the time.

Quality of contact was an emphasis for us from January on. We worked on it a variety of ways with 40” pvc skinny pipe bats that are handle weighted, a skinny bat with loose shot that moves from the hands to the end of the bat when the bat head is released, Trey Hannam’s half bats and most of all I bought a Sports Attack I-Hack machine. It has a random speed setting that I use almost every session. I also do a fair amount of two drop ball/two rise ball sequences. (As well as always doing full windmill front toss from behind a screen.) She also hits with a former mens player that can throw with great spin and speed. This does her more good than anything I can do with her because they battle. Sometimes I swear they hate each other. The love comes back when it’s over but it can be pretty icy.

So what results do I see in hitters- mine specifically. In the cage, tighter gap to gap, more up the middle hitting. Dd is a righty that tends to look outer half/outside to get balls to right center and right field. I see her hitting more up the middle. When we hit on an open field, she has shown a lot more power- I agree with you that better contact equals better hits/power.

Sorry To get so long winded. To me everything in hitting is big picture. I can almost never find “one thing” that works.

 

[_MIA_]

http://baseball.physics.illinois.edu/AJP-Feb2003.pdf

 

[fanboi22]

bobby is that you? Lol. The faster the bat goes the quicker you are out of the hitting zone. The Shorter time your bat will be on plane. It works both ways. You guys cant see the forrest for the trees.

read the very first post again.Number 2 bullet point. The BEST players have LoWeR bat speeds.

https://www.drivelinebaseball.com/2019/05/debunking-bat-speed-myths/

'Using wOBACON as a measure of performance, we find that batters perform best when bat speed is between 90-95% of their max-effort swing, and they struggle when bat speed is below 85% of their max-effort swing.'

This was the first article that popped up. Couldn't really find any others.

 

[Work=wins]

https://www.drivelinebaseball.com/2019/05/debunking-bat-speed-myths/

'Using wOBACON as a measure of performance, we find that batters perform best when bat speed is between 90-95% of their max-effort swing, and they struggle when bat speed is below 85% of their max-effort swing.'

This was the first article that popped up. Couldn't really find any others.

The number could be relative to what they push as their agenda. What needs to be looked at is what the best players bat speeds are compared to the fastest of their peers. Since those aren’t readily available, what’s a guy to do? Maybe check the video? Do the best look like they are max effort? Mostly no. Like I said before, why is timing so important if bat speed is king? We should just be able to catch up right? Hmm. JD said his swing looks max effort, but he’s not max effort at all. Hmm. Why do these guys work so hard on being short etc when max speed is king? Things just aren’t adding up to training a maxed out swing imo.

 

[fanboi22]

The number could be relative to what they push as their agenda. What needs to be looked at is what the best players bat speeds are compared to the fastest of their peers. Since those aren’t readily available, what’s a guy to do? Maybe check the video? Do the best look like they are max effort? Mostly no. Like I said before, why is timing so important if bat speed is king? We should just be able to catch up right? Hmm. JD said his swing looks max effort, but he’s not max effort at all. Hmm. Why do these guys work so hard on being short etc when max speed is king? Things just aren’t adding up to training a maxed out swing imo.

Do you think training max will help when you then goto less than max? Get all maxed out and out of control, which may make it feel easier and more controlled when you slow down? Or always just train at the speeds for game swing?

 

[BigSkyHi]

Do you think training max will help when you then goto less than max? Get all maxed out and out of control, which may make it feel easier and more controlled when you slow down? Or always just train at the speeds for game swing?

Most will train less than max to control the stroke they are looking for. In the game they are counting on the adrenaline to reach game speed.

 

[fanboi22]

If you look at some of the ODM Testing information (the link below shows the 2020 girls) a lot of hitters in the 80 mph bat speed but ball exit doesn't show as fast as bat speed until around the low 70's to upper 60's. I would assume their testing equipment is consistent. I think they use Blast.

https://odmtesting.com/level-i-2020/

 

[Work=wins]

Do you think training max will help when you then goto less than max? Get all maxed out and out of control, which may make it feel easier and more controlled when you slow down? Or always just train at the speeds for game swing?

I think both have benefits.. feeling maxed out and where or how far you can control. I think kids that are very mobile should swing with more intent than tighter kids. They might need too. But first I would get the swing right, then find out where they lie on the spectrum. For instance does a kid need bigger moves to feel loaded? If so, a heavier bat and more intent might be perfect. vice versa for a tighter one.

 

[rdbass]