Every parent and coach has watched youth baseball games where one kid seems to consistently drive the ball harder than everyone else. The question has always been: is it just size, or are there deeper physical qualities at play? A 2025 study by Bordelon and colleagues sought to unpack this, testing 49 youth players (average age 11) to identify which physical measures best predicted batted ball velocity. The results provide fascinating insight into how body size, lower-body power, and rotational strength shape hitting performance at the earliest competitive stages.

What the Study Found

Bordelon et al. tested a range of field-based performance measures: broad jump, grip strength, hip external rotation strength, and basic anthropometrics like height and weight. After accounting for body size, two qualities stood out: standing broad jump distance and nondominant hip external rotation strength.

The data showed that every 10 cm increase in broad jump translated to roughly 1.4 mph more batted ball velocity (p < 0.001). Similarly, a 10 N increase in nondominant hip external rotation isometric strength predicted a 1.1 mph gain (p < 0.001). Broad jump was the single strongest predictor among all field tests, while grip strength correlated with exit velocity but didn’t provide additional predictive value once body size was considered.

Perhaps unsurprisingly, body size remained dominant. Height and weight together explained 64.1% of the variance in batted ball velocity, underscoring just how influential growth and maturation are at this age.

Why This Matters

The implications are twofold. First, until puberty begins to level the playing field, stature and mass will drive much of the gap between performers. Bigger kids hit the ball harder. But the second insight is more exciting for development: lower-body power and unilateral hip strength show predictive power even after controlling for body size. That means youth athletes who may not yet have size on their side can still differentiate themselves through training qualities.

This is where broad jump becomes especially interesting. It is simple, cost-free, and reliable, yet it carried more predictive value than grip strength or even rotational hip measures. For coaches, it suggests that a youth athlete’s ability to project force horizontally may be more tied to early hitting power than any isolated strength metric.

The Role of Lower-Body Power in Hitting

Biomechanically, hitting is a ground-up sequence. Force is generated through the legs and hips, transferred through the trunk, and delivered via the hands and bat to the ball. The standing broad jump is a proxy for this kind of explosive force production. It is not a perfect replication, but it captures the neuromuscular qualities needed to project the body rapidly in a coordinated way.

For 11-year-olds, this may also serve as a window into coordination development. At this age, many athletes are still learning to integrate full-body movement patterns. A strong broad jump suggests they are further along that developmental curve, which then translates into more efficient kinetic chain sequencing during hitting.

Hip External Rotation Strength: Why the Nondominant Side?

One of the more nuanced findings was the role of nondominant hip external rotation strength. For right-handed hitters, that means the left hip—the lead hip that anchors the front side during rotation. Strong external rotation here allows an athlete to decelerate rotational forces, stabilize posture, and redirect energy efficiently through the swing.

Think of it as the “brake” that allows the body to stop leaking force. Without adequate strength here, an athlete may open early, drift, or collapse through the front side, robbing the swing of exit velocity. The study highlights that even at age 11, these stabilization demands are not trivial—they can predict measurable differences in performance.

Size Versus Skill: The Developmental Question

The dominance of height and weight in the regression analysis (64.1% of variance) raises an uncomfortable truth: at youth levels, much of performance differentiation is biological. Parents and coaches often confuse early physical success with long-term potential, when in reality, body size is confounding the picture.

However, this is also where training comes in. Broad jump and hip strength provide windows into trainable qualities that exist alongside growth. They remind us that even if stature rules the day now, athletes can build the foundational tools that matter later. In fact, those who build power and coordination early may benefit disproportionately once size catches up.

Practical Applications for Coaches and Parents

So what does this mean for applied training? A few key takeaways:

• Track broad jump: It’s easy, reliable, and predictive. Tracking improvements here may reflect improvements in force production relevant to hitting.
  
  
• Incorporate unilateral hip strength work: Simple isometric holds, resisted band rotations, or controlled external rotation lifts can build the qualities highlighted in the study.
  
  
• Don’t chase grip strength as a proxy: Grip strength has value, but once body size is accounted for, it adds little predictive insight.
  
  
• Respect body size’s role, but look deeper: Bigger kids may dominate, but qualities like power and stability will separate athletes over time.
  
  

How We Apply This at VeloU

At VeloU, we see this study as validation of what we’ve long emphasized in training youth athletes: simple, targeted measures can explain a surprising amount about baseball performance. We integrate broad jump into testing because it not only provides predictive insight but also gives athletes a goal they can understand and pursue. Improving hip strength, particularly on the nondominant side, has been part of our developmental programming for years.

Perhaps most importantly, this reinforces our belief in appropriately supervised strength training for athletes as young as 11. While many parents worry about early exposure, data like this suggests that power and stability are not just safe to train but foundational. With proper progression, they set the stage for later performance, long after size alone stops being the great differentiator.

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The Bordelon et al. (2025) study shines a spotlight on two qualities that matter in youth hitting: explosive lower-body power and unilateral hip stability. While size continues to dominate outcomes, these measures show that controllable, trainable qualities are already influencing performance at age 11. For coaches and parents, the message is clear: if you want to prepare youth athletes for long-term success, track the broad jump, strengthen the hips, and build power early.

References

Bordelon, B. et al. (2025). Field-testing measures related to youth baseball hitting performance. Journal of Strength and Conditioning Research.

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