This page is NOT meant to resolve the argument about training with weighted balls. Rather it provides guidelines on numerical factors related to training with any and all baseballs that weigh over 5 oz. Of course, as more than one instructor points out, that 5 oz regulation game ball is itself a weight to be managed. Also, if you're looking for pitch count guidelines, click here.

Before looking at charts and measurements, it's important to note that every pitcher will have a maximum velocity and an optimum velocity, and they aren't the same. Naturally, the whole point of pitcher development is to keep raising the bar - getting an improvement in pitching performance. That goes far deeper into the art of pitching than velocity, and is covered on other pages in WebBall on consistency, endurance, etc. This page is about velocity.

The general guideline would be that whatever the 1 rep maximum (1RM) pitching velocity of a pitcher might be, that he should have a functional maximum of 95% of that speed. The reason is that the final 5% of velocity might require a 20% effort reserve. In other words, you are asking a lot to expect not only one but 20-30 or more pitches to be at anything better than 95% of max. So let's call 95% the functional maximum.

Now even that 95% FM is not his optimum velocity for pitch after pitch. So you might want to benchmark a value at perhaps 90% of 1RM to be the optimum fastball velocity, hoping he can rear back and get 95% max when really required, without pushing to 100%.


So let's get to training and where or if weighted balls fit in.

Ball Weight	Velocity with same effort	Speed Differential (mph)	% Drop
5 oz	90 mph	-	0%
7 oz	78 mph	-12	13%
10 oz	65 mph	-13	28%

One of the researchers/instructors in the field has come up with an expectation conversion chart (our term, not his). His information says that if a pitcher can throw a 5 oz ball at 90 mph, then the same effort will move a 7oz ball at 78 mph and a 10 oz ball at 65 mph.

Ball Weight	Speed Differential (mph)	Velocity (calculated)	% Drop
5 oz	-	90 mph (assumed)	0%
7 oz	-6	84 mph	7%
14 oz	-6	78 mph	13%
21 oz	-6	72 mph	20%

Another high-level instructor who focuses more on pitcher conditioning uses greater weights... 7, 14 and 21 oz or more. His experience shows a 5-1/2 to 6 mph drop each time the weight goes up by one of those increments.

Ball Weight	Speed Differential (mph)	Velocity (calculated)	% Drop
4 oz	0	90 mph (assumed)	0%
5 oz	2-3 mph	87-88 mph	3%
6 oz	2-3 mph	84-86 mph	6%
7 oz	2-3 mph	81-84 mph	9.5%

And a third instructor who is a former Major League pitcher and pitching coordinator quotes a 2-3 mph drop between weights when the changes is just 1 oz, for instance 4 oz, 5 oz, 6 oz and 7 oz baseballs.
To help you decode all this, we have not only charted their numbers but added calculated columns in an effort to get apples to apples, sort of. The % drops are not always consistent, in fact depending on which guru you accept, the loss in velocity is from 3% per extra ounce, to as much as 6% per ounce.
The important - in fact critical - point in all this is that you cannot expect to throw a heavier baseball as fast as a regulation weight without a significant increase in the physical effort required. So the mere act of working with weighted balls, requires you to recruit the body's muscles and sequence the momentum transfer much more efficiently, more fluidly, and more intently. So you had better be fully warmed up - sweating even - and have very good mechanics BEFORE you start to push the velocity with weights beyond the sliding scales shown here.

And that, of course, is the bottom line in our view. If the readings on the radar gun show only the relative % drop we show here, then you may be throwing a weighted ball, but not with any more training effort and therefore not with any purpose or performance improvement.