What cutting drills, teenage knees, and vitamin C have in common


Three stories *from the field* in my world this week with the TLDR highlights included for your scanning pleasure:

1. A Cut That Doesn’t Land

This morning I was on the field with a pro athlete and another coach, troubleshooting mechanics for an athlete coming back from a brutal double injury: both his ACL and patellar tendon were ruptured last June.

He’s only a few sessions into cutting and sprint drills but we’re already noticing red flags we want to fix.

Today’s standout issue: his torso leans away from his direction of travel during cuts. That’s usually a compensation, and in this case, we suspect the cause is a capsular block at the knee that’s limiting flexion in swing. He can’t get low, so his upper body leans to make space.

This aligns with the Cutting Movement Assessment Score paper HERE, which links trunk lean, wide lateral foot placement, and poor foot progression angles to higher knee abduction moments - a common precursor to ACL re-injury.

What we want:

What we don't want:

We’re working on mitigating the risks, knowing that if we can’t regain flexion, we need a plan to coach around it. And if you can guess why lack of swing flexion might cause this lean - hit reply. I’d love to talk shop.

2. The Weakest Group Wasn’t Who I Expected

Last weekend, I taught dry-land sessions at the Art of Performance Skate Camp by pro figure skater Elladj Balde and Michelle Dawley for nearly 100 figure skaters. The athletes ranged from age 10 to adult and what I noticed in the 14–17 year old girls group surprised me.

They had to sit out more drills than any other group (the 10-13's, the 17-25's and the adults).

They reported the least # of strength training sessions/week than any other group.

They were the weakest group in functional strength: few could do a proper push-up, trunk stability push-up, or skater squat.

Most weren’t playing any sport outside of skating.

In contrast, the 10–13 year olds and the adult rec skaters moved better and trained with fewer complaints.

It’s a pattern I see more and more: teenage girls pushed into early specialization without the strength to support the load. We wouldn’t expect a new lifter to handle a max squat three days a week - so why do we expect young skaters to train 6 days/week without robust strength and expect them to lead low-injury and long-lasting careers?

One to keep thinking about. And one that floats around my LinkedIn often in my networks raising the question about long-term athlete development. Here's a good post on the topic I saw recently.

3. A Cold That Wouldn’t Quit (and the Vitamin That Helped)

One of my national team biathletes came off her break and just couldn’t shake a cold. Four weeks of low energy, lingering cough, and no training momentum.

That’s when I remembered this paper my colleague Nick pointed out a while back on vitamin C titration to bowel tolerance.

Here’s how it works:

  • Start with 1000mg/day of vitamin C
  • Increase by 1000mg daily until you hit gut upset
  • Drop back to the last tolerable dose
  • Stay there until symptoms resolve

It’s crude, but effective. Some athletes need 8,000–10,000mg/day in periods of high stress or immune suppression. Within four days, she was better.

Just a reminder: science doesn’t always need to be complicated to be useful.

That’s all for now... but if any of these stories sparked a thought or question, I’d LOVE to hear from you.

Yours in physiology,

Carla

Physiology Toolkit

We're devoted to individualized training and rehabilitation, offering a detailed & measured approach to athletic performance. We've honed our expertise with elite competitors and Olympians in triathlon, bobsleigh, and track, and now bring the same methods to the everyday athlete eager to improve their health and minimize injuries. Access evidence-supported tips delivered through true tales, jaw-dropping examples, and clear exercise videos that make them easy to grasp and apply.

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