The Knee JournalRunning6 min read
For runners whose knee is fine on the run and sore on the stairs
Fine for two miles. Then the stairs, one at a time.
If your knee is fine when you head out and sore by mile two, or the next morning, it's probably not your knee. It's the tendon one inch below it. Here's what helps, and what doesn't.
You know the run. The first mile feels great. Somewhere around two, there's a catch just under the kneecap, and you start running carefully. You finish anyway. Then the stairs at home remind you about it, and the next morning too.
That pattern has a name, and a very specific location: one inch below your kneecap.
What most runners try first
- ✕Compression sleeveDown by mile three, every time$25
- ✕Hinged braceFine for walking. Ridiculous for running$60
- ✕Ibuprofen before the runQuiet run, loud stairs the next morning$8 a month
- ✕Kinesiology tapePeeled off with the sweat$12
- ✕New running shoesLovely shoes. Same knee$140
- ✕Two weeks offBack on the first run after—
A normal run, and the day after
- Mile 1Out the doorFeels fine. Feels great, actually.
- Mile 2The catchA sharp spot just under the kneecap. You slow down.
- Next morningThe stairsOne at a time, hand on the rail.
It's the tendon one inch below your kneecap
Every stride lands on the patellar tendon, the strip just below the kneecap, thousands of times a run. Going downhill or down the stairs, it brakes for you too. Physical therapists see it all the time in people who started running more.
That's why it hurts a couple of miles in, on the stairs and the next morning, and why it's easy to point to with one finger.
The sleeve slides down. The brace is for walking.
A sleeve squeezes your whole knee, traps the heat and ends up around your shin by mile three. A hinged brace locks everything, including the stride you're trying to keep. Ibuprofen quiets the run and moves the pain to the stairs.
They all treat the whole knee. The trouble is in one spot.
A strap that presses on that spot, with an airbag inside
A patellar strap puts steady pressure right on the tendon. In one study, 16 of 20 people showed less strain on the tendon with a strap on.
Ours adds two things for running: a U-shaped notch that cups the kneecap so it can't ride down when you sweat, and a sealed air pocket in the pad that compresses every time your foot lands and springs back.
Outside: flatNot on the run. On the stairs afterwards.
Most runners forget they're wearing it after the first mile. What they notice is the stairs after the run, and that they stopped running carefully at mile two. It's not a miracle. It's less load on one small spot.
Before you buy anything for your knee, check these 5 things
From us or from anyone else.
- It sits just below the kneecap, on the tendon, not around the whole knee.
- It stays put from the first mile to the last, sweat included.
- It's thin enough to forget under your running shorts.
- You can run with it for weeks, and get your money back if it's not for you.
- Something inside takes the shock when your foot lands. Ours has an airbag in the pad; most straps don't.
Strap, sleeve or brace?
| What matters | Second Set | Sleeve | Brace |
|---|---|---|---|
| Presses on the tendon below the kneecap | ✓ | ✕ | ✕ |
| Airbag that takes the landing | ✓ | ✕ | ✕ |
| Stays put on a sweaty run | ✓ | ✕ | ✓ |
| Thin enough for running shorts | ✓ | ✓ | ✕ |
| 60 days to try it, full refund | ✓ | ✕ | ✕ |
It won't fix your knee. It lets you keep running while you fix it.
Nothing here regrows a tendon. What the strap changes is where the load lands while you run, so you don't have to stop. The other half is strength: wall sits, slow squats, step-downs on your rest days. That's why the 8-week plan comes free with every strap.
Sharp pain, swelling, or a knee that gives way is a different story: see a physical therapist before you buy anything.
One for each knee. Or one for your running partner.
Most runners we hear from feel it in both knees sooner or later, and half their running group has the same story. That's why the strap comes as Buy 1, Get 1 Free: one for each knee, or one for the person you run with.
One for each knee, or one for your running partner. Free tracked shipping and 60 days to try them on real runs.
Sell-Out RiskHigh
The 60-day run test
Wear it on your real runs. Sweat in it. If it isn't for you after 60 days, you get a full refund, worn or not.
Try it risk-freeStraight answers
Will it fix my knee?
No, and we won't pretend it does. It puts steady pressure on the patellar tendon while you run, the spot physical therapists often target with a strap. The free 8-week plan is there for the strengthening part.
Is it the right strap for my pain?
It's made for pain just below the kneecap that shows up a few miles in, on the stairs after a run, or the next morning. Pain inside the joint, swelling, or a knee that gives way? See a PT first.
Will it slide down when I sweat?
The silicone pad grips the skin and the U-shaped notch cups the kneecap, so it stays where you set it, first mile to last. Set it once with the metal slider, then just close it before you head out.
Does it rub or chafe?
It's two inches tall and the band is soft and breathable. It sits below the knee, not behind it, so there's nothing folding when you bend.
Which size do I need?
One size. The slider and the hook-and-loop fit it to your leg one inch below the kneecap. If it doesn't fit, the 60-day guarantee covers it.
What do I get?
Your strap (two with Buy 1, Get 1 Free) and the free 8-week knee plan by email, the same day.
This is an advertisement by Second Set. It isn't medical advice.