ACL rehab and knee coaching from a board-certified sports PT. If your knee still feels weak or off months after surgery — start here.
I'm Dr. John Kahl, PT, DPT, SCS, CSCS — a board-certified sports specialist and strength coach who works exclusively in knee & ACL recovery.
Cleared at 9 months. Quad never came back. Extension never came back. Confidence never came back. That's not bad luck — that's a system that underloads you and calls "no limp" a successful outcome.
Every video breaks down what your rehab should look like: quad strength testing, range of motion, graft selection, exercise progressions, real return-to-sport criteria, and the mistakes that stall recovery at months 3, 6, and 12.
For active adults who want to ski, run, lift, and compete again. Not just "function."
New long-form videos 2–3× per month.
🎯 Book a free discovery call: www.johnkahldpt.com/aclrx-discovery-yt
📩 Instagram: @acl.rx
ACL reconstruction · ACLR rehab · online physical therapy
John Kahl PT DPT SCS CSCS
Nobody talks about the cost of "good enough."
Skipping the hard sessions feels like a win today. It's not. The quad you didn't load this month is the strength gap you're still chasing next year.
"Just give it more time" sounds patient. But time heals tissue. It doesn't rebuild strength, restore extension, or teach your knee to trust a hard cut again. That takes loading. On purpose. With a plan.
And "I'll do it tomorrow"? That's how 6 months turns into 2 years of a knee you don't trust.
Specialized help has a price. So does skipping it. One is an investment. The other can show up as a sport you quietly stopped playing... or a knee that runs your life instead of the other way around.
You don't get to avoid the cost. You only get to choose when you pay it.
Ready to stop paying the long term price? Book your free call in bio
1 day ago | [YT] | 1
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John Kahl PT DPT SCS CSCS
"Why isn't my surgical leg catching up?"
Most common question I get. And the honest answer is that it's rarely about effort. Most people I talk to are working hard. They're just working hard at a plan that was never built to close a gap.
The one that surprises people most is the good leg.
Nobody tells you to stop training it. It just quietly falls out of the program while everything gets pointed at the surgical side. Then testing day comes, the symmetry number looks better, and it gets read as progress.
But a ratio can improve two ways. Either the weak side came up, or the strong side came down.
Only one of those means you got stronger.
Swipe through for the 6 that actually move the needle 👆
Comment "LAGGING" and I'll send you the full video where I break down each one.
5 days ago | [YT] | 14
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John Kahl PT DPT SCS CSCS
Your surgical leg is still weaker than your other one. You feel it on stairs. You feel it when you land.
Here's the part nobody explains: you've been training both legs the same way for months. Same exercises. Same sets. Same order. And the gap hasn't moved.
You don't close a gap by treating both sides the same.
These are the 6 rules I use with my clients to bring a lagging quad or hamstring back up to speed. Swipe through 👉 and save this for your next leg day.
Comment "LAGGING" and I'll DM you the full video breakdown — free.
6 days ago | [YT] | 9
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John Kahl PT DPT SCS CSCS
Pain on the knee extension machine?
It's probably not the exercise. It's the programming.
Most people use one tool — straight reps — when there's a full toolbox most never touch.
In this carousel I break down the 3 isometric variations I use with my online clients to build quad strength, calm anterior knee pain, and drive real adaptations — without flaring the knee up.
👉Comment "ISO" and I'll DM you the full video breakdown — free
1 week ago | [YT] | 6
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John Kahl PT DPT SCS CSCS
Getting cleared isn't the finish line. According to the research, it's when second ACL tears pile up.
I broke down a review of the return-to-sport research after ACL reconstruction. Most people make it back to some sport. Far fewer make it all the way back. And 9–29% re-injure (up to 1 in 5 in young athletes).
What actually predicts who stays healthy isn't the calendar. It's finishing rehab, true strength symmetry, full knee motion, a stable knee, and a head that's ready.
Swipe through 👉 Save it for the checklist on slide 9.
Comment "TEST" and I'll DM you my full return-to-sport testing breakdown, free
1 week ago | [YT] | 5
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John Kahl PT DPT SCS CSCS
Spending money on supplements after ACL surgery?
Most of what's on the shelf has never been tested on an ACL patient.
I went through two research reviews and every ACL-specific supplement trial I could find, then ranked them. S tier to F tier. The #1 pick might surprise you… it isn't a supplement at all.
Swipe through and save this.
👉Comment "FUEL" and I'll send you my free Rehab Fuel Calculator, with your calorie and protein targets for every phase of rehab.
2 weeks ago | [YT] | 6
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John Kahl PT DPT SCS CSCS
Two years after a quad tendon ACL graft, the average quad is still under 90% strength.
That's 18 studies and 952 reconstructions pooled together.
Here's the part that should bother you: most people get cleared for sport around 9 months. At that point the pooled average sits around 76%. And returning to sport under 90% is associated with a higher rate of new knee injury.
The quad tendon is a good graft. But it takes strength out of the exact muscle you need most, and almost nobody gets retested after month 8, so the plateau goes unnoticed.
The graft sets your starting line. Rehab built around your specific graft site is what closes the gap.
Swipe through 👉 and comment "GRAFT" — I'll send you the full video breaking down each graft type.
2 weeks ago | [YT] | 10
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John Kahl PT DPT SCS CSCS
Most ACL recoveries are harder than they need to be because people skip one critical phase: prehab.
What you do before surgery plays a huge role in:
• Quad strength
• Knee motion
• Swelling
• And how rehab feels afterward
😯And it can even help some people avoid surgery completely
I broke this down step-by-step in a new video.
👉Comment “PREHAB” and I’ll send it your way.
2 weeks ago | [YT] | 55
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John Kahl PT DPT SCS CSCS
They'll call it obsessive right up until it works.
A story I hear all too often: an ACL patient is "cleared" or discharged based on some arbitrary calendar date. No testing. No baseline data. No plan.
This often results in a quad that's still 20–30% weaker than the other side, compensation patterns, and missing range of motion. And then if they get hurt again, everyone calls it bad luck.
Now this isn't true for everyone, but it's a very common reality - a copay gets you 30-60 minutes in a room with someone managing five other patients, working off a protocol that ends at week 16. That's not a knock on your PT. That's what the model allows them to realistically do.
What it doesn't get you is someone who knows your strength scores, your confidence scores, your graft, your sport, and what your leg needs to do in month 11 that it didn't need to do in month 6.
Fourteen months of work nobody clapped for. A lifetime of being active again that no one can ignore.
👉Book your free call in bio if your knee still doesn't feel like yours.
3 weeks ago | [YT] | 17
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John Kahl PT DPT SCS CSCS
Three months post-op and still missing motion isn't a time problem. It's a plan problem.
This client came to me just under 3 months after ACL + meniscus surgery, short on both extension and flexion.
One week later: +10° flexion. +5° extension.
Still not full. I'm not going to pretend it is.
But look at the rate. That's what one week looks like when the work actually targets and measures motion instead of waiting on it.
Most people aren't stalling at 3 months from a lacknof effort. They often need to channel their efforts in the right direction. With a meniscus repair, early restrictions leave motion limited, however, consistent progress is the key.
That motion gap doesn't stay cheap. It leaks into every part of rehab down the line.
👉Comment "ROM" if you're 3+ months out and still missing motion for my free guide
1 month ago | [YT] | 4
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