If you've ever had a sore knee after a week of jumping, an aching Achilles after a long downwinder, or a burning forearm from holding the bar in gusty wind, you've met the tendon gap. Muscles get stronger fast. Tendons, which connect those muscles to your bones, take much longer to catch up. When your muscles can produce more force than your tendons are ready for, the tendon pays.
1. Why Tendons Are Slow
- Less blood flow: Muscles have a rich blood supply. Tendons have far less, so nutrients arrive slowly and repair takes longer.
- Months, not weeks: Muscle visibly adapts in a few weeks of training. Meaningful tendon remodeling takes several months of consistent loading.
- Load is the signal: Tendon cells (tenocytes) build new collagen in response to mechanical load. Too little and the tendon weakens; too much too fast and it gets irritated. Steady, progressive loading is the sweet spot.
The Two Golden Rules
Isometrics calm pain: holding a strong contraction without moving (45 seconds or so) has been shown to reduce tendon pain right away. Slow and heavy builds tendons: lifting with a 3 to 4 second lowering and lifting tempo is one of the best-proven ways to strengthen tendons. Fast and bouncy trains muscle power; slow and heavy rebuilds the cables.
2. The Kiter's Tendon Routine
Do these twice a week off the water. Twenty minutes is enough.
1. Spanish Squat Holds (Knees)
Loop a thick resistance band around a solid post and step into it so it sits behind both knees. Walk back until it's tight, then sit down into a squat with your shins vertical and hold.
Why it works: Loads the patellar tendon heavily without stressing the knee joint. Great for jumper's knee, the classic kiter complaint.
2. Slow Single-Leg Calf Raises (Achilles)
Stand on one foot on the edge of a step, holding a dumbbell for extra load and something for balance. Lower your heel below the step over 4 seconds, pause, rise over 4 seconds.
Why it works: Heavy, slow loading is what tells the Achilles to lay down new, well-organized collagen.
3. Tibialis Wall Raises (Shins and Ankles)
Lean your back against a wall with your feet a step in front of you. Pull your toes up toward your shins as high as possible, hold, lower slowly.
Why it works: Strengthens the front of the shin, your braking system for flat landings and choppy water.
4. Slow Wrist Extensions (Forearms and Elbows)
Rest your forearm on a table, palm down, holding a light dumbbell. Help it up with the other hand, then lower it slowly with the working arm only.
Why it works: Targets the extensor tendons behind tennis elbow, common in riders who grip the bar hard in gusty wind.
3. Feed the Rebuild
Loading tells the tendon to rebuild; nutrition gives it the bricks. In a study by Keith Baar's lab, people who took 15 g of gelatin with vitamin C an hour before a short bout of exercise doubled a marker of collagen production compared to placebo. Bone broth, gelatin or collagen peptides plus some fruit before your tendon routine is an easy habit.
- Glycine: About one-third of the amino acids in collagen are glycine, and your body may not make as much as it needs for optimal collagen building. The daily sachet we take has 2 g of it.
- Ca-AKG: A building block for proline and a helper for the enzymes that stabilize collagen fibers (more in Reversing the Biological Clock).
- Hyaluronic acid: A key part of joint fluid and connective tissue, also in the daily sachet.
- Vitamin C: Required for collagen production. Fruit does the job.
4. Respect the Lag
Three big days in a row is where tendons get angry. After a wind streak, take a lighter day: gentle mobility, a hang from a bar, a few isometric holds. That quiet window is when tenocytes lay down new collagen. Build up your jumping volume over weeks at the start of a season instead of going from zero to ten. Your tendons will thank you for the next 30 years of riding. For the bigger picture of protecting your joints, see The Anti-Fragile Kiter.
Fuel Your Collagen Matrix (10% Off)
Glycine, Ca-AKG and hyaluronic acid all come in the DoNotAge daily sachet, together with 12 more longevity ingredients. Pair it with your collagen or bone broth before training. Use discount code KITEHOMIEZ at checkout for 10% off your entire order.
Shop DoNotAge →Free: The Kiter's 10-Minute Flexibility Routine
The mobility and core routine we use before and after sessions, as a free PDF. Plus new videos and posts every few weeks.
This article is for general education and isn't medical advice. Talk to your doctor before starting a supplement or a fasting routine, especially if you are pregnant, have a medical condition or take medication. Some links on this page are affiliate links: if you buy through them, we earn a small commission at no extra cost to you.