Should Kids Use Weighted Baseballs? What Coaches and Parents Need to Know

On a recent Reddit thread in r/Homeplate, a parent raised concerns about a coach using weighted baseballs with an 11U travel team.

The debate quickly expands to a broader question: Is it safe or appropriate for preteens to be using weighted baseballs to increase pitching velocity? And what about players just a few years older? This article dives into the science, the risks, and what the experts say about introducing weighted-ball training for kids between the ages of 11 and 14.

Weighted baseballs are commonly used in training programs to increase throwing velocity. They come in a variety of weights—both heavier (overload) and lighter (underload) than regulation baseballs. The theory is that changing the load on the arm can improve arm speed, coordination, and strength. Many high school, collegiate, and professional players use them as part of advanced throwing programs.

There are several types of weighted balls used in baseball training:

• Overload Balls: Heavier than a standard baseball (5 oz), typically ranging from 6 oz to as much as 32 oz. These are intended to help build strength and increase muscle recruitment.
• Underload Balls: Lighter than a regulation baseball, usually between 3 oz and 4 oz. These are used to improve arm speed and help pitchers develop quicker movement patterns.
• Plyo Balls (Plyometric Balls): Often soft-shell rubber balls of various weights, used for short, high-intensity throwing drills designed to improve mechanics and build arm durability. Common weights range from 100 grams (~3.5 oz) to 2 kilograms (4.4 lbs).
• Command Balls: Slightly under- or over-weighted balls used in command or control drills, often designed to challenge consistency in release point and movement.

Each type of ball serves a different purpose, but their usage must be tailored to the athlete’s age, physical maturity, and level of experience. Using the wrong type—or using them incorrectly—can increase injury risk, especially for younger players.

It’s easy to see the appeal. In a world where youth baseball is increasingly competitive, even small velocity gains can help a player stand out. But at what cost?

A controlled study published in the Orthopaedic Journal of Sports Medicine found that youth pitchers who used weighted balls increased their velocity by about 2–3%, but the injury rate was concerning: 24% of participants in the weighted ball group reported an injury during or after the training period, compared to 0% in the control group.

Younger athletes—especially those under the age of 16—are still developing physically. Their growth plates (especially at the elbow and shoulder) are open and more susceptible to overuse injuries. Conditions like Little League elbow, which results from repetitive stress on the growth plate, are a serious concern.

Studies show that throwing heavier balls puts extra stress on the inside of the elbow, especially on the ligament often injured in Tommy John surgery. It can also force the shoulder to rotate more than it’s used to, which can lead to pain or injuries if it happens too quickly.

Even at the professional level, opinions on weighted balls are mixed. A study of minor league pitchers found that those who used weighted ball programs were more likely to suffer injuries and miss playing time. And in a survey of elite players, 73% believed weighted balls carry an increased injury risk—yet many still used them, likely due to performance pressure.

For 11-year-olds—and most kids under 14—the risks far outweigh the benefits. Experts recommend:

• Avoiding weighted balls altogether for prepubescent athletes
• Focusing on throwing mechanics, core strength, and shoulder stability instead
• Incorporating lighter (underload) balls for advanced 13 to 14-year-olds under professional supervision only
• Ensuring full rest periods and pitch count compliance

Rather than chase velocity gains with risky training methods, coaches and parents should prioritize long-term arm health and skill development. That includes:

• Regular strength and mobility training
• Proper warm-ups and cooldowns
• Progressive long toss programs
• Rest periods—ideally 3 to 6 months per year without overhead throwing

It’s tempting to reach for tools that promise quick results, especially in competitive youth sports. But when it comes to weighted balls, the science is clear: they carry real risk, especially for athletes who are still growing. At age 11—and even into the early teen years—it’s better to wait, build a solid foundation, and focus on healthy development.

Let your young athlete grow into their game. The velocity will come—but only if the arm stays healthy enough to keep playing.