I've been writing a lot about AI lately, but today I want to write about the polar opposite.
I want to document what I've been doing as a coach to improve the physical capacity of elementary school kids.
Deep in Youth Baseball
My eldest is about to enter sixth grade.
When he started youth baseball in the autumn of his fourth year, our family's weekends became completely organized around baseball.
My second son followed and joined the same team, and around that time I got seriously involved as a coach — that was March of last year.
It's almost been a year now.
These days on weekends, I'm up early packing lunches for everyone and running around to practices and games.
Sometimes my two-year-old daughter and wife get swept along too — we'll spend an entire day at a school field, half of us playing baseball, the other half on the playground equipment.
In the midst of all this, I've recently taken on a specific responsibility as a Strength & Conditioning (S&C) coach for the team.
The manager asked me to "improve the overall athletic ability of the team," and I now design and lead a training program for all the kids — including my own — every week.
How I got the assignment: apparently word reached the manager that "he seems to have coached American football," and the fact that I'd been running sprints full-out alongside the kids during every practice didn't hurt.
Improving Athletic Ability
Let me briefly describe my own sports background.
I have zero baseball experience whatsoever.
But I've been active continuously from elementary school through today — basketball and skiing as a kid, rugby in high school, American football in college, and since becoming an adult: weight training, running, swimming, and stretching.
As a child I was quite overweight and had very tight hips — hardly what you'd call "naturally athletic."
But I can't stand being still, and I love sports and physical activity — which is why I keep going.
Today's competitive sports demand more and more physical athleticism. Everyone is expected to become an athlete.
It's not just about raw strength — athletes need fine control of their own center of gravity to maximize their output in movements and contact situations, or to absorb force safely.
This requires advanced body control techniques, the joint mobility and muscular flexibility that supports them, and the development of the nervous system.
Training theory has also become highly specialized — agility, stability, plyometrics — advancing rapidly.
In my case, I spent a lot of time on this kind of training during college, and also studied it as a coach.
What I experienced then was the surprise and exhilaration of: "my body can now move the way I imagine it should," and "my output has clearly gone up."
I said I "wasn't naturally athletic as a kid" — and yet my athletic ability has continued to grow even into adulthood:
- Couldn't do a chin-up (backward roll on a bar) in elementary school; first succeeded at age 35
- Was afraid of water; first swam 100m freestyle at age 36
- First hit a ball in a batting cage that actually flew into the home run zone at age 38
More than anything, learning new physical movements is still just as fun as it was when I was a kid — and the sense of satisfaction hasn't changed.
Once you experience "I can do something I couldn't do before," you build the mentality and energy of "I can overcome what I can't do yet."
This is how the capacity to acquire athletic skills develops on both the mental and physical dimensions.
I call this capacity athletic ability — broadly defined.
Incidentally, a book I've been reading lately argues that exercise is also essential for strengthening brain cells.
Stages of Athletic Development
There's a model called the LTAD — Long-Term Athlete Development model.
Proposed by Canadian sport scientist Istvan Balyi, it's been adopted by Olympic committees and sports federations around the world.
The LTAD model is built around the idea of optimizing training content based on each individual's "growth spurt" (the period of rapid height increase), and defines five major developmental stages:
- Fundamental: Ages 6–9. Basic movement through play.
- Learn to Train: Ages 9–12. Focused on skill acquisition.
- Train to Train: Ages 12–16. Aerobic capacity and speed.
- Train to Compete: Ages 16–23. Specialized technique and power.
- Train to Win: Ages 19+. Peak performance.
Elementary school kids fall right across the boundary of stages 1 and 2.
Put simply: younger grades develop a variety of movements through play, and as they move into upper grades, they gradually begin to "train" basic athletic skills.
The critical point here is: never specialize too early.
Learning only baseball skills, or only soccer skills, is not the goal.
I've tried many different sports myself, and you can never know in advance which sport suits you best until you've tried it. People take on new sports well into their twenties and beyond.
What elementary school kids need most is to build a foundation that will serve them in any sport they encounter later — and to carry home the feeling that being good at physical activity is fun.
Designing Training for Elementary Schoolers
Using these theories as a foundation, the question of how to design training for elementary schoolers is my core challenge.
Currently I'm designing programs using the LTAD concept of multi-sport, multi-movement experience (ABCs).
I try to incorporate baseball movements where possible, while building in a balanced mix of flexibility, stability, explosiveness, and agility.
For example, I've built a Notion database with training objectives and movement descriptions shared with parents (the image below shows part of the menu in use):
Each menu item has a YouTube link attached so parents and kids can build a visual image together before trying the movements. Describing physical motion in words is hard...
Elementary schoolers also find it difficult to grind through repetitive drills quietly. So the program needs variety and rhythm — competition, game-like elements — to keep them engaged without getting bored.
At the same time, we need to raise heart rates and warm up the muscles, so there's a lot to think about when putting a program together.
Here's an example of a session:
| Item | Details | Duration |
|---|---|---|
| Warm-up | Jogging, static stretching | 7 min |
| Dynamic stretching | Dynamic stretching for each joint and major muscle group. 8 exercises. | 8 min |
| Jump rope | Good for agility and balance. 5 exercises. | 10 min (5 sets of 1.5 min + 0.5 min rest) |
| Ladder drills | Multi-movement combined drills. ~10 exercises. | 20 min |
After this, the team moves into baseball-specific practice like catch.
Training Results
It's only been about a month since we started, but the kids' athletic ability has unmistakably improved:
- A child who couldn't coordinate their limbs and couldn't step through the ladder at all can now move through it at a decent speed
- A child who couldn't do a double-under jump rope did it several times in a row
The effects are real and strong. The kids themselves are clearly pleased.
There are three things I find valuable about this training approach:
- Wherever these kids are starting from, their athletic ability will improve
- It will translate into baseball performance over the medium term
- "Getting better" becomes a source of joy and confidence
The third one is what I care about most.
I want to give these kids the joy of getting better at using their bodies.
Not everyone will make it to a national high school baseball tournament (Koshien). Some kids will quit baseball. Some will move on to other sports.
But I want them to enjoy a lifelong relationship with physical activity — one they can weave into their lives over the long haul. Because that's the kind of life I aspire to myself.
The Value of Physical Capacity in the AI Era
Physical things. Real things. Human things.
The body is the supreme example of all three — and I believe its value will only grow from here.
I care deeply about physical capacity in my own life, and I'd love to give my kids the experience of discovering that physical capacity matters.
AI and the digital world will flood into their lives whether they want it or not.
If sport and physical activity become a tool they can use to step away from that world — that would be more than enough reward for a coach.
