How to Strengthen Tendons: A Joel Smith Q&A

Based on Episode 71 of the Just Fly Performance Podcast, a solo listener-question Q&A with host Joel Smith.

This episode is a grab bag of listener questions, and the first one sets the theme for the best of them: how to strengthen tendons. Joel Smith’s answer is not a single exercise but a principle, and it runs through his thinking on feet, fascia, and jumping. Along the way he works through how his squat philosophy shifted after interviewing Mike Boyle, two ways to lay out a sprint week, why a rigid foot matters, what the sprint “push” actually is, and the recovery methods he thinks are underrated. What follows pulls the most useful answers together.

Key Takeaways

• Strengthen tendons with variability, not repetition. Any plyometric loads the tendons; the key is many different takeoffs, angles, and surfaces at relatively low intensity.
• Same jump every day makes you worse. Loading the identical line of strain repeatedly leads the body to protect itself, which is why single-drill jump programs sap an athlete’s spring.
• The squat is a means, not a sacred cow. After Mike Boyle, Joel leans front-squat and single-leg dominant and uses goblet squats to earn the front squat.
• Match the week to the athlete. Neural, wired athletes often thrive on a medium-high setup with back-to-back quality days; others need the classic high-low.
• Sleep beats gadgets. The highest-return recovery tools are sleep and, underrated, visualization and meditation.

How to strengthen tendons: build variability, not the same jump

Joel starts from the fact that tendons respond to the stretch-shortening cycle, so almost any jumping builds them. The distinction that matters is how varied the loading is.

Any plyos will build your tendons. Anything that uses the stretch-shortening cycle puts a premium on tendon development. But the key, in my perfect world for athletes, is plyometrics in a high package of variability.

His illustration is the basketball player versus the high jumper. A hooper jumps in dozens of subtly different ways every game and keeps their spring; a high jumper who takes the same full approach every day slowly loses it.

You do the same exact jump over and over, loading the tendons along the exact same lines of strain and force. The brain is pretty smart. It says, if we keep doing this, eventually I’m going to get hurt, because this is overuse. So to build tendons, you have to build along subtly different lines of stress, using different takeoff angles, means, methods, and surfaces.

He also flags what not to reach for. High-intensity depth jumps are the wrong tool for the job of building tissue, and the whole process is slow.

Lower intensity and very fast contact is generally better for specifically building the tendons. Using depth jumps to create that stimulus isn’t necessarily the best idea, because you’ll fry your nervous system before you get a chance to build up those tendons. It builds up over years and years.

In practice that looks less like a program and more like a habit: barefoot work on grass, jump rope, low-intensity hops, playing sport, all layered underneath the high-powered training rather than competing with it.

The squat, after Mike Boyle

Joel is candid that his squat thinking moved after having Mike Boyle on the show, and that the hard part is psychological, because coaches love the lifts they came up on. His own path in through track and field made it easier to treat exercises as interchangeable.

Once you get past the assumption that you must back or front squat heavy to achieve a particular vertical jump or 40-yard-dash result, and throw that out the window, it psychologically helps a lot of people.

He has not banned anything, but his defaults changed. He runs more front-squat and single-leg work, and he borrows a progression idea most coaches apply one rung higher.

A lot of coaches use the front squat to earn the back squat, but it’s not a bad idea to use the goblet squat to earn your front squat. For a team-sport athlete, or working with swimmers, goblet squats compared to back squats, the risk-reward is totally reasonable.

The deciding question for him is whether an exercise is worth the one athlete who misses a week to a tweak when a lower-risk option would have trained the same quality.

Two ways to lay out a sprint week

Asked about high-intensity/low-intensity days versus alternating track and weight days, Joel lays out the classic Charlie Francis high-low, then his own favorite for jumpers, a “medium-high” week where the medium day is lifting and the high day is jumping. Which one fits depends on the athlete’s wiring.

Really wired athletes, the type ones, don’t do as well when they take extended days off. If they rest more than two days, their dopamine drops and they go flat. So the back-to-back days with a bit more intensity keep that engine running hot, and you get a better jump day by having an appropriately dosed lifting day before it. Appropriate dosage is the key.

He would push 100 and 200 types toward more of that weights-then-sprint pairing, and steer 400 types back toward the traditional high-low, while watching for the athletes who crash on repeated high-intensity days and need a deload every third week.

Train the foot for rigidity

Since interviewing Chong Xie, Joel has made foot training a priority, and his answer on the rigid foot is unequivocal. He points to the feet of elite athletes as the tell.

You look at Rafael Nadal’s foot, one of the best in the game, and he has that hyper-arch foot. The best athletic players, almost invariably, if you can see their feet, have that foot.

Working barefoot with his tennis players, he found flat feet and collapsing toes, and used a photo of Nadal’s foot to sell the athletes on what they were building toward. He is clear that this is trainable and that most athletes should chase it, with one memorable exception.

The foot should absolutely be trained for a rigid foot, no doubt. There’s only one exception, and that’s long-course swimming. You do not want a hyper-arch foot there. That will hurt you very badly.

What the sprint “push” really is

One listener asked how to push properly when sprinting, and Joel credits Darien Barr for sharpening his own understanding. He defines the push by geometry rather than feel.

Look at the moment the stance thigh is perpendicular to the ground, and see how far the foot is behind the hips. A good push is when the foot is farther behind the body, because you’re trying to run horizontally. A very vertical push is like a golf ball bouncing on concrete, vertically but not fast horizontally.

Two fixes he uses: “squatty runs,” acceleration runs with lower-than-normal hips that force the pushing position and a faster front-leg recovery, and more aggressive arm action, since the arm driving down and forward helps the same-side leg deliver force into the ground.

Recovery: sleep first, then your mind

Joel admits he is not a recovery enthusiast, precisely because he wants his attention on what pays off most. His ranking is blunt.

The number one thing by far is sleep. If you spend 20 minutes in the cold tub chatting with your buddy and you’re only getting six hours, you probably should have spent that on sleep.

Beyond sleep, the tool he thinks is most underused is not physical at all.

A recovery method with a ton of power that people don’t talk about is visualization and meditation. Setting aside time for a meditative visualization of your body recovering and getting into the parasympathetic state, because people don’t de-stress enough, and it teaches you to be present.

Frequently asked questions

How do you strengthen tendons for jumping and sprinting?
With high variability at relatively low intensity. Joel argues that any plyometric builds tendons through the stretch-shortening cycle, but repeating one identical jump loads the same line of strain and eventually causes the body to protect itself. Vary the takeoff angles, methods, and surfaces, favor fast, low-intensity contacts over heavy depth jumps, and treat it as a multi-year habit layered under your main training.

Does microdosing work for jumping and speed?
For specific purposes, yes. Joel once added three inches to his vertical in a week of daily depth jumps before the effect tapped out, and he finds microdosing best for two situations: getting back up to speed quickly after a lull, and stabilizing gains while peaking for competition. He is more cautious about it as a standalone long-term system, since higher-level athletes eventually need more rest between hard sessions.

Should distance and marathon runners do plyometrics?
Sparingly. Joel notes that endurance athletes already ride the razor’s edge of injury from their mileage, so piling on intense plyometrics like bounding and hurdle hops adds risk. He favors basic strength work, goblet squats, lunges, step-ups, and some glute work such as hip thrusts, over aggressive plyometrics for that population.

How often should you practice a skill like dunking?
About twice a week for most people, with the two sessions kept different, for example low-rim work one day and full attempts the next, or a vertical emphasis versus a horizontal one, to preserve variability. Alternatively you can microdose roughly five attempts on more days, ideally at the end of a workout when you are potentiated.

Can you sprint at top speed with a weighted vest?
Joel sees little wrong with a vest at 5 percent of bodyweight or less for flying runs, as long as mechanics do not degrade, though he notes a belt-style device or a motorized unit lets you dial the resistance in more precisely.

About the author

Joel Smith is the host of the Just Fly Performance Podcast and the founder of Just Fly Sports, a former collegiate strength and track and field coach who specializes in speed, power, jumping, and athletic development, with a particular interest in fascia, foot function, and the training methods on the edges of the field. Listen to the full Q&A on Just Fly Sports.