Is Weighted Baseball Training Dangerous For Pitchers?

Weighted ball training for pitchers is one of the hottest, most controversial—and misunderstood—topics in baseball circles today. I’m writing this article because I know a great deal about weighted ball training and I’m very concerned about its potential, in the wrong hands, to wreck arms. However, my conclusions may surprise you.

If you pitch or coach pitchers, I strongly urge you to take time to read and understand this content. The health of your arm or your program likely hinges on what you will read here—whether you currently use weighted ball training or not.

Our discussion starts here: Is it really true that high intensity weighted ball training causes injury? Undeniably, yes, but that’s only one very small part of the story. Let me explain.

Currently there are two primary schools of thought about weighted ball training:
• Weighted balls are inherently dangerous and there are better alternatives for training pitchers.
• Weighted balls offer massive gains for pitchers and are worth the risk.

These differing viewpoints have led to the current controversy surrounding weighted ball training for pitchers. Proponents of both camps are increasingly vocal about their opinions, to the point it’s getting nasty. If you’re not familiar with the weighted ball war-of-words going on between Driveline and Top Velocity, google it.

However, I’m suggesting a third school of thought about high intensity weighted ball training:
• It’s possible to throw heavy weighted balls without risking arm injuries—if you understand technique that puts the arm in the strongest possible place, at the right time.

Let’s look at some undeniable facts:
• If you don’t throw weighted balls and have poor technique, you’re eventually going to get hurt.
• If you throw weighted balls with poor technique, you’re going to get hurt…and you’re likely to get hurt more quickly.

These facts lead to a different question: Does high intensity weighted ball training (and pitching in general) have to wreck arms? The answer is wrapped up in technique and mechanics.

Based on extensive work with weighted balls, I know with certainty the following statements are true:
• If someone is telling you weighted balls MUST cause injury and you should avoid them, they don’t understand how to use the arm in a way that prevents injuries.
• If someone is telling you weighted balls are a great way to train and pitchers training under their protocols are getting hurt, they don’t understand how to use the arm in a way that prevents injuries.
• If someone is telling you weighted balls are a great way to train, and their technique for throwing weighted balls doesn’t identically match throwing or pitching technique, what they’re advocating is highly likely to damage arms over the long haul.

I know these statements are accurate because I’ve rehabbed pitchers with elbow and shoulder injuries who’ve never touched a weighted ball, and are using only ‘arm care’ programs. I’ve also rehabbed pitchers who injured elbows and shoulders throwing weighted balls. In both cases, my rehab protocol always includes intensive weighted ball training. However, there’s a massive difference: 100% of my long term students are staying healthy (and none of my students are using a typical ‘arm care’ program).

Here’s what separates my approach from all others…

Based on many years of experimental weighted ball training with pitchers, the following is true: If you can’t throw a heavy, one- or two-pound weighted baseball with maximum intensity, again and again, with the same technique you use on the mound, it reveals a weak, broken link in technique that is eventually going to hurt you, whether you throw weighted balls or not. I strongly suggest you reread this statement and contemplate it’s implications.

In my experience, it’s possible to use weighted balls to quickly teach and learn ideal, anatomically sound pitching and throwing technique. Weighted ball training has the massive benefit of providing immediate feedback about where the body is strong. If you throw a heavy weighted ball and it causes pain, you’ve got a problem with mechanics and technique.

By putting a heavy weighted ball in a student’s hand and helping them experience where their entire body is operating with maximum strength and efficiency, it’s possible to use weighted balls for strength phase training. Students are able to experience throwing and pitching where their body is strongest, with maximum leverage. In my experience, baseballs are too light and too familiar-feeling for students to experience where the body is strongest and most powerful.

Using weighted balls, I’ve also found it’s possible to progress from strength-phase training to power-phase and speed-phase training, similar to training athletes for other ballistic speed events like javelin. I accomplish this by systematically working with progressively lighter balls. There’s another added bonus: this process helps efficiently transfer skills to the lighter baseball, embedding critical motor skills that keep arms healthy.

Based on my longterm findings, I offer the following recommendations:

If you don’t know with ABSOLUTE certainty that technique being taught will protect arms, I highly recommend you avoid throwing weighted balls.

However, if you avoid weighted balls because you’re afraid of what they’ll do to your arm, most likely you already have mechanical flaws that are going to wreck your arm (even if coaches and instructors or scouts are telling you your arm works ‘properly’). You can learn for yourself how to identify one of these flaws, linked directly to Tommy John surgery, on my blog article, Why Baseball Is Destroying Pitcher’s Elbows.

Bottom line recommendation: I HIGHLY recommend you learn to train with weighted balls, with the caveat you MUST understand technique that will protect the arm.

If mechanics and technique are such a big deal, what programs or instructors are teaching technique that will protect the arm? Many claim they are, but based on my observations: none of them. This includes the most prominent instructional programs in baseball. Featured in videos from high profile programs, I consistently see techniques being taught that lead directly to injury.

How can I make these claims? Because of experience and expertise I’ve gained through 15 years and over 30,000 hours of experimental research with pitchers, I’m in unique position to judge what’s happening in any other pitching program. You might find this arrogant or egotistical. It’s not and I can back it up. It was Bear Bryant, longtime Alabama football coach, who said, “It ain’t braggin’ if it’s true.

Since 2003 I’ve been doing long term weighted ball training with pitchers. I believe my experimental research work with weighted ball training is more extensive than the following programs combined: National Pitching Association, Driveline, the Texas Baseball Ranch and the Florida Baseball Ranch.

There’s a reason I’ve fixed problems with pitchers from each of the programs listed above: they don’t understand specific mechanical issues that compromise the arm and body. I’m not going to detail these mechanical issues here, but techniques taught using concepts like arm spiral and roll-ins, or connection balls, reveals significant misunderstanding about how the arm is designed to work. Based on what I’ve learned, it’s easy to look at video clips from each program and identify uncorrected mechanical flaws in their pitchers that contribute directly to injury. And when you add the stress of weighted balls to an already flawed motion, there’s trouble ahead. I encourage you to be very, very careful who you’re listening to.

I suspect I know more about weighted ball training than anyone in the world. I know with absolute certainty that weighted ball training, done wrong, amplifies risk of injury. Because of this concern I’m writing this article. I also know with 100% certainty that it’s possible to use heavy weighted balls and retrain pitchers to avoid arm injuries, by changing critical parts of the pitching motion.

I want to make crystal clear, I’m not here to start a war. I’m here to help and I wish people would start reaching across the fence instead of trying to defend their turf. Baseball’s ongoing arm injury epidemic causes me deep sadness. It’s possible right now, today, to eliminate most pitching elbow and shoulder injuries. Essentially no one understands this; not trainers and coaches, nor physicians. What pains me most: the majority of current injuries were preventable before they happened. I hope you’ll reach out and learn what I have to offer. I understand it’s up to me to prove what I know.

Using a drill set and very specific mechanics I’ve developed, I’m able to build pitchers up to a point where they throw literally thousands of high intensity weighted ball reps every year. Plus, they’re able to throw long, frequent bullpens. My students throw so many pitches— without pain or injury—that it refutes the concept of overuse as a primary cause of arm injuries. The root of baseball’s arm injury epidemic isn’t overuse, it’s lousy mechanics that many believe are good mechanics.

I hope you’ll contact me and find out what these changes to mechanics involve. By changing how they use their arm and body, using intense weighted ball training, I’ve successfully rehabbed pitchers with shoulder labrum tears, without surgery. And the last Tommy John guy I rehabbed was back on the mound throwing competitively within six months after surgery, throwing harder than ever before. According to conventional wisdom that’s not possible.

The pitchers I’m training are not getting hurt and they’re not in pain. They’re proof that it’s possible to get stronger by throwing, instead of shying away from workloads. Their velocities go up, they build strength and endurance with high throwing volume and, because they are able to throw longer and more frequently, they have the potential to become much more highly skilled than pitchers who are limited by pain or fear of injury.

There’s a better way to train pitchers. It starts with mechanics that can be used to throw heavy weighted balls at maximum intensity, using them to train for strength, power and speed. You might guess that this opens the door for elite trainers to apply their skill set in a different way.

There’s much more to my program than weighted balls. Training figures significantly in this equation. My unique blend of training techniques couple brain training with strength, agility and mobility work. This training results in stronger, healthier, more adept pitchers. Regardless of the activity, everything always boils down to technique. If you lift weights with poor technique, you’re eventually going to get hurt. The implement doesn’t cause the damage, it’s technique, and the same holds true for pitching and training pitchers.

If technique produces damaging movement patterns it doesn’t matter how hard athletes train, even under guidance of the most sophisticated protocols and ‘arm care’ programs and ‘prehab.’ If mechanics are flawed, it doesn’t matter how strong you are. Instead, it will always result in eventual injury or, at bare minimum, result in decreased performance. This precisely describes pitcher training programs as we know them today.

Don’t get me wrong, I’m a huge fan of intense training protocols that build overall athleticism and promote high intensity. However, training by itself, without understanding the root mechanical causes of injuries, is futile. Intense training with weighted balls, with poor technique, is guaranteed to cause damage. That damage may take time to manifest, but the damage is still being done.

If you or your students experience elbow pain or shoulder pain when throwing, you have a problem with mechanics and technique. The same holds true for pitchers with lower back, oblique, and adductor (groin) pain. Pain is your body’s way of saying, “DON’T DO THAT.” It’s certainly possible that other factors like muscle imbalance and insufficient training contribute to pain, but the overriding factor is still technique.

If you are limited to short bullpens because of pain, or fear of pain, you have a technique problem. It’s remarkably easy to prove: I routinely help students eliminate pain simply by changing technique.


If you can’t throw a weighted baseball with everything you’ve got, again and again, it reveals a weak, broken link in mechanics that is eventually going to hurt you, whether you throw weighted balls or not.

I know the above statement is true, no matter what ANYONE says: technique problems, not overuse, are leading directly to injury. I’m positive.

Leading doctors of the day told Roger Bannister that breaking the 4-minute mile would kill anyone who attempted it. Bannister, a medical student, studied running and training in ways that went against the grain of tradition. He defied the status quo and shattered the 4-minute barrier. It didn’t kill him, and in the next year many other runners achieved the same. What I’ve learned about pitching injuries is a breakthrough of this magnitude.

There’s direct parallel between Bannister’s story and pitching as we know it. Prominent doctors today, led by renowned surgeon Dr. Jim Andrews, keep telling us that pitching injuries are caused by overuse. However, my students are doing exactly the opposite of what is advised. Based strictly on our throwing volume—numbers of pitches thrown—my students should be blowing up left and right. They’re not. So, why are they staying healthy? It’s time to break through this artificial overuse barrier and deal with the root cause of pitching injuries—mechanics and technique.

In my experience, changing technique to meet very specific criterion, pitchers stay healthy. The key is in knowing what technique is healthy.

Healthy technique involves a continuum of movement patterns, and everything must operate in sequence, at the right time. I’ve spent thousands of hours examining high speed imagery, then exploring technique changes with pitchers. This research has led me to understand discrete, identifiable, mechanical flaws that cause the vast majority of pitching injuries. It’s relatively easy to correct flaws once we understand what we’re observing. With my help, anyone who is adept can learn to identify and correct these mechanical issues.

The secret behind my approach has been learning to isolate injury-causing techniques, then training in a way that builds a better mousetrap. I’ve been doing this day in and day out for over 15 years. It works, and I’ve repeated the results many hundreds of times. I’m able to change mechanics of pitchers who are injured or hurting, eliminating their pain by throwing—instead of doing conventional rehab. I can teach this to anyone who wants to learn.

If you or your organization have arm issues, shoot me an email ([email protected]) and we can talk about how I can help. I’ve already done the hardest part of the work for you. You have absolutely nothing to lose and everything to gain. Let me prove to you I know what I’m talking about.

If you’re serious about ending arm injuries and lessening the economic and human costs for your organization, this represents an opportunity to lead. Challenging? Yes, and the rewards will be measured on a legacy scale.

If this sounds like your kind of challenge, let’s band together and work toward ending baseball’s arm injury epidemic.

I’m looking forward to getting acquainted.

Bill Peterson