How To Get Stiffer Tendons
Welcome back to the THB Strength podcast. On today's episode, we are gonna be talking about tendon stiffness and how important it is and if stiffer tendons are better and how important it is for athletes. But before we do that, we wanna give a huge shout out to our sponsors over at THP Strength, the premier jump coaching service in the entire world. If you're looking to jump higher, get more athletic, and stay healthy, go to thpstrength.com. Right now, we're running a special for $99 a month, which is approximately one seventh the price it used to be.
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John:That said, let's get to it. Boys, what do we wanna what do we wanna talk about? Woah. You good?
Isaiah or Austin:I was about to die.
John:Okay. Yeah. Alright. Tendons. Tendons.
John:Tendons. What do we think about tendons? Relevant tendons. We got the Achilles. We got the patella.
John:We got the hamstring tendon. Isaiah, you've been reading about tendons, haven't you recently? I have. What have you learned?
Isaiah or Austin:I know that tendons differ in property from muscles. Well, I guess first we have to define what a tendon even is.
John:There you go. What have you been learning about tendons?
Isaiah or Austin:It's a tendon, for those of you that know, is a muscle. It's the in between point between a muscle and a bone. A muscle, when it contracts, it pulls on bone, it allows you to move all your limbs, and the tendon's what's pulling on that bone. And tendons and muscles have different properties. The coefficient of stiffness in a tendon is constant.
Isaiah or Austin:You can't change it. But the coefficient of stiffness in a muscle changes depending on its tension. So the harder you contract your muscle, the stiffer it becomes, and that has huge implications for performance later on. Generally, you like to you you always hear coaches mentioning you want stiffer tendons or maybe not coaches, but just people in general saying that you want stiffer tendons. Is this necessarily true, John?
Isaiah or Austin:Do you always want stiffer stiffer stiffer
John:not always better. Stiffer is not always better. You know, it's it's not whether it's bigger. It's how you use it. Okay?
John:So if you are a very stiff actually. Sorry. Okay. So if you have really, really stiff tendons, you might run into issues, especially depending on where that tendon is located. Tendons don't really care about the type of you good?
Isaiah or Austin:Dude, I think when you drop that, like lean back a little bit and go flying. I don't
John:think it's I don't think we're gonna flip. I think we're good. We're sturdy. Alright. Sorry.
John:So if you like, it doesn't matter what type of contraction you have. You could have an isometric, you could have a concentric, you could have eccentric muscle contraction. Tendons don't care. All they care about is the amount of force going through it or the tension going through it, and that determines how much it will stretch and thus how much energy it's going to store and then subsequently release. So tendons that are very, very, very stiff are going to have they may or may not stretch very much.
John:And
Isaiah or Austin:Also, we should also define what is even the benefit in stretching a tendon. Like, what are what's what's the purpose
John:behind If if you stretch a tendon, it can store energy and it can release energy because it is non contractile faster than a muscle can. Muscles are limited in their rate of contractility, right? They can't essentially shorten infinitely fast, but tendons are very, very quick at shortening because they're non contractile. So it's basically this material that your muscle is connected to, and as a result, muscle is gonna determine how much that stretches, but the rate at which you have deformation and how much energy you get out of it is determined by the tendon, how thick it is, what it's made of, and how long it is.
Isaiah or Austin:And that's what elasticity is. Elasticity is how much material wants to return to its original length.
John:Or shape. Or shape. It's deformation. It's stress strain. Yep.
John:So it's like how much does it deform and how much energy you get out of it and what on the return. How much do you get as well? So there's some some concepts that are pretty complex that I'm not even gonna pretend to fully fully understand. One of them is hysteresis, which is like when it does deform and then return to its normal shape, how much energy do you lose to heat? And how does that change when you repeatedly load it?
John:How does it change when you load it fast versus slow? That plays a role. Right? And so you obviously want an efficient transfer of energy. That way you're able to get as much out the jump as possible.
John:So your muscles play a big role in determining that, but also in terms of the tendon, what it's made of, like I said, how stiff that tendon is. But stiffer is always better because if you don't apply enough force, you might not deform the tendon at all. So if you have a super, super stiff tendon, you actually might not be able to deform it or deform it much from the muscle or you might not be able to continue to deform it through whatever muscle contraction you're doing, thus not really getting you much energy out of it.
Isaiah or Austin:I think the best way to put it, describe the worst type of athlete.
John:Oh, the worst type of athlete is someone whose tendons are impossibly stiff, they do not budge, and then their muscles are very, very weak and also have very low rates of force development. So if you have no ability to stretch the tendon and you are not very good at generating force eccentrically, then you're probably not going to be able to deform the tendon at all and you're not going be able to store energy and and use that energy to jump upwards.
Isaiah or Austin:And then can you describe because I think this will this will help everybody understand the concept too. Can you describe what the ideal tendon and force generating properties are for, like, basketball player and for a high jumper
John:Okay.
Isaiah or Austin:Sprinter? Like, how how would you change their their tenant properties?
John:So I think, like, for athletes that don't have a lot of time to produce force, like in basketball, you're largely, your success is dictated by how quickly you can do something or get someone off off balance and cut around them or or move around them. And so the time intervals under which you're functioning are really short. Be successful in a sport where you don't have a lot of time to to do something, you need to have really high rates of force development. However, because you don't have a lot of time, the muscle can't produce it doesn't have time to produce a lot of force. Right?
John:So if you you know, and and usually there's not big change of directions or or there's not a lot of time to store a lot
Isaiah or Austin:of energy either. Can't Or like space.
John:Yeah. You don't have space to generate momentum and use it to your advantage, which is what happens in in high jump or dunking, you know, where you have a lot of time and a lot of space to build up a lot of energy that you can use during the takeoff. Basketball, you don't have that luxury. So you're basically holy shit.
Isaiah or Austin:Oh, really? Loud car.
John:What if we just saw a cop just blitz by? That was like a charger. Yeah. Anyway, so if you're a basketball player and you're cutting or changing direction, you're basically relying on your muscle's ability to generate concentric force. You don't have much of a a pre stretch.
John:You don't have much of the augmentation that happens from a stretch shortening cycle because you don't have a lot of time to stretch the tendon. You don't have a lot of force to stretch the tendon. So the more you can pull concentrically with the muscle and stretch the tendon from doing that, the better off you're gonna be. If your tendon's too stiff, you're not gonna get any energy from it. And so what needs to happen is you need a relatively soft tendon that the muscle can tug on really, really easily, so you're able to get a lot of energy return out of the tendon.
John:Now if you're a high jumper, you need a really that's like complete opposite, basically. Right? Not complete opposite, but it's very different. You need a lot a lot of force, and you need a lot a lot of stiffness in the tendon, so that you're able to maximally produce a shit ton of force on the ground. And you have a lot of you have as much time as you want to do that.
John:So if you take a full run up that takes you thirty seconds, but it wouldn't take thirty seconds, it'd probably take eight or something like that, that's fine. It doesn't matter. All the momentum you use in the run up and you build into the takeoff and then, you know, your muscle strength also has to be super high to handle it, that's gonna really benefit you. Because if you're a high jumper at the elite level, you're probably super, super powerful both eccentrically, concentrically, and isometrically. So we don't fully understand what happens in the muscle at every muscle fascicle, meaning the the actual contractile part during a takeoff, but we know that the muscle can produce a shit ton of force, during that activity.
John:So they have to be super strong, my guess is eccentrically and isometrically to handle it, and then continue to generate force through the takeoff, and a stiffer tendon is gonna be more beneficial. So in their case, they're super stiff tendons, and they have very, very, very explosive and strong muscles to be able to continue to not only handle the momentum of their takeoff foot hitting the ground, but they can continue to produce force through the takeoff and maximize the energy that is stored in the tendon and utilize it very So
Isaiah or Austin:I guess the answer to the question, guess first it should be like, do you even want stiffer tendon? Like you should look at the activity you're doing and then decide. Remember the whole point of getting a stiffer tendon is because you can stretch it more and it'll store more energy and it'll hypothetically make you jump higher than if you were just concentrically pushing up. But if you are not strong enough and you're in a sport like basketball where you don't have a lot of time, it actually might be detrimental to have too stiff of a of a tendon. What what do you do if you're that athlete and your tendons are too stiff?
John:Gets your muscles so explosive and strong that you can generate a lot of force despite that. Yeah. That's generally kinda or you play to your strengths. Right?
Isaiah or Austin:And I think that's that's also the benefit of having good jump technique. Yeah. Is you're able to eccentrically load. Yeah. Even more.
John:You you probably have to pick movement strategies that really favor you, you know, so you'd have to be a different type of player. And you if you're at that level, you know, the NBA level especially, you're probably already doing that. Like I would think James White has super stiff tenants. He's not going to really perform well overt. You know he's probably not going to perform well off a static change of direction or something like that.
John:But if he's a guard and he's bringing the ball up the court or something like that on a fast break, yeah, he has a lot of momentum he can work with and so he can use that to his advantage. You know if you're someone like. Trying to get it like. Like Steph Curry or something like that, he's probably one of those guys that doesn't have insanely insanely stiff tendons. He's able to use his tendon properties to his advantage and change the direction really effectively.
John:You watch him try to get open or you guys have probably seen the clips where it's him just trying to get an open three and he's just moving around screens left and right, change of direction, being really shifty on the court and he gets typically a lot of open shots. Reason being his change of direction ability is really, really impressive and his tenants are probably such that. It's beneficial for him or he's able to get open. Right? That's the type of player he is.
John:If you're looking at someone like try I was trying to just trying to think of someone who's, like, short stocky, doesn't have, a ton of vertical, can't really do anything on the court, but is like you know what I'm talking about?
Isaiah or Austin:Dealing no. Not dealing.
John:Griffin Grieves. Think of Stefan Holmes, on the basketball court. Like, does that even exist?
Isaiah or Austin:Not really.
John:Yeah. That doesn't really that's not even really a thing.
Isaiah or Austin:It would have to be it would probably be some dude who's, like, just shoot threes all day, but you take him outside of the court and tell him to go dunk. He might be really athletic. He might
John:be a freak.
Isaiah or Austin:I've seen guys like that. Really? Yeah. Not not I don't think in the NBA, but I've seen, like, just players that you would never expect to be able to dunk, and you freaking take them outside of the court. Nick Briss is actually kinda kinda like that.
Isaiah or Austin:Yeah. Like, in a half court setting, he's not gonna be dunking.
John:No. He won't.
Isaiah or Austin:No. But you put him on a fast break or in between games?
John:Yeah. Nick is probably the best example
Isaiah or Austin:of that. Fly.
John:Yeah. He'll fly. And then he's shifty, though. Like, he has really good movement patterns and stuff. Yeah.
John:But he does something interesting. He moves almost exclusively on his toes and he doesn't laterally. You're not going to see him get into these wide splits that like Steph Curry would get into and things like that. He's typically going to stay nice and high and kind of almost jump into changes of direction so he's able to load his tendons.
Isaiah or Austin:Yeah. So with the meta for, like because the average viewer is probably gonna be someone that's just trying to dunk. Right? Would the would the ideal scenario be, I mean, one, you'd wanna get your RFD really freaking high up. So whatever tenant property you have, you still wanna be able to stretch them.
Isaiah or Austin:And then after that, I guess it is beneficial. Take someone like from in my case, probably would benefit from getting stiffer tendons as long as I can keep my peak force high enough where I can stretch them. How do you what's what what is the answer to how do you get stiffer tendons in that scenario?
John:Strength work. Strength work is pretty clear cut in terms of increasing tendon stiffness. I What
Isaiah or Austin:kind of strength work?
John:So it's there's two things that matter when it comes to changing attendance properties, right? One is time and one is tension. The type of muscle contraction doesn't freaking matter. You could do isometric, you do eccentric, you do concentric. It doesn't That matters because biomechanically, when we're doing activities, we need to use an eccentric muscle contraction.
John:But if you only cared about the tendon, it's just force. Right? So like a distance run off distance runner for example. Right? They have incredibly stiff tendons.
John:Super stiff tendons. Right? Why is that? Well, because they're impacting the ground however many times a week at a pretty high force with pretty high rate of force development. Right?
John:Yeah. So the rate of stretch probably also maybe plays a role, but like maybe the the the rate of deformation matters too to an extent because that's also gonna change the tendon property. But if you just wanted to get stiffer tendons, you just need a shit ton of tension in it for long periods of time and relatively quickly happening really, really frequently. Right? So jumping a lot?
John:Jumping a lot is gonna give you stiffer tendons.
Isaiah or Austin:What about what about for the Achilles? What would happen to your tendon properties if you're doing a lot of like heavy calf raises? Let's say like sets of five for a month. Would your?
John:Sets of five? Yeah. You're probably that would that would also do it. That would also really stiffen the the Achilles. Like there's one
Isaiah or Austin:Is there anything that will make the tendon compliant? Like if you want more compliant tendons, is that even possible? Or are they just gonna stiffen up over time as you load them?
John:Soft. I mean, maybe stretching, not loading it. Light loading really slowly. Really, really, really slowly.
Isaiah or Austin:Yeah.
John:Really sub max I would think that sub maximally loading it really, really slow where the cross bridging I forget what it's called. There's a name for it. Oh my gosh. There's a name for when you you load it really, really slowly, and basically the cross bridges break and it it kind of like increases the compliance over time, like the stress shielding breaks apart. Keith Barr talks about it.
John:I saw Ben Moxness talk about it on his story the other day. But that's good for rehab, but it's not really good for performance. So if you only did really, really, really slow reps sub maximally
Isaiah or Austin:Yeah.
John:Like basically tendon rehab type stuff, that could potentially, you know, because you're not meeting the threshold for tenant adaptation. Right? Your force is really low. Your rate of force development is really low, and you have a decent amount of time, but, you know, it's it's not a a meaningful So
Isaiah or Austin:so what I'm getting from this is, they're gonna stiffen up over time, but at the end of the day, getting better at producing force and producing it fast is always gonna be king. Yeah. And it's mainly your tendon properties are specificity. 99% determined by your genetics.
John:I think it it is, but it's modifiable. Like, plyos we see change joint prop joint stiffness properties. We don't and we see performance change. It's really hard to measure tendons in those activities because the tests are usually really shitty.
Isaiah or Austin:But you should never be worried about like remember our example of this stiff tendon athlete sucks at producing force? Right. His abilities to produce force is gonna improve at a faster rate than his tendon is stiffening up.
John:Right? Oh, it should. Yeah. It should. I mean, unless you're neurally really shitty, your nervous system is just whack.
John:Yeah. Like So at that point done something
Isaiah or Austin:Take drugs?
John:I don't even know.
Isaiah or Austin:You probably
John:need I really can't. Take cocaine or something like that to get your nervous system to activate. That'd be like the only way. You need a crazy stimulant to get your central nervous system to recruit force. Demonetize.
John:Demonetize. Yeah. You need a stimulant. A very strong stimulant to get it to produce you know, to get your nervous system up regulated or you need to be studied.
Isaiah or Austin:Yeah, it's
John:like see why you can't activate your neuromuscular system effectively. Maybe the sensitivity to receptors is down regulated like, you know, when we see a neuron fire, it gets a bunch of chemical impulses that add up. They're graded and then, you know, you release chemicals from the through a synapse that connects on the other side of the neuron and then that you know chemicals are coming into another receptor and then the whole process is happening over and over again. Down all the way through the nerves into the muscle where calcium is released in the muscle and then the muscle contracts, you know actinomize and bind and then yeah that process happens. So maybe that's where they suck.
John:Yeah. Maybe the chemicals in their they either don't have a lot of that chemical in their body, maybe they the neurons are thin, maybe, right? Because we see that type two fibers or have alpha motor neurons, which means they're thicker and better at propagating action potentials. They're more effective at doing it. They're better at getting the graded potentials.
John:They're they're better at having the potassium and, let's see, sodium. They're better at moving those across the the neurotransmitter. It has like a membrane. So maybe that's one of the reasons why. But at the end of the day, if you're training to be more explosive and your intent is really high centrally, you're gonna be training that to be better and more effective and happening faster.
John:So at the end of day, always wanna do that. But if you're hurt all the time and maybe this is like the the caveat is injury is gonna. Make that difficult, right? If I told you to go high intent on every single exercise, what would happen?
Isaiah or Austin:Yeah, hurt. You're gonna
John:get hurt, so you can't necessarily do that. Some athletes want to try and there's one guy right now, Hideaki, who's trying it. I was like, yeah, you can try to do super high intent activity, super high velocity activity the whole time, but it's high risk. Right? And if you're at that point where you're kind of plateauing and you're healthy, it's a good thing to employ.
John:Or if you're if you wanna even take it a step further, you could do complexes, supersets of high intent activity with high intent plyometric or something.
Isaiah or Austin:Right?
John:So you're kinda surfing the the ends of the curve. You're you're actually trying to push everything up when you're doing that. Right? But it's dangerous. The the reward is high, but the risk is also high.
John:So I at a point, maybe that's not worth it. The more compliant thing, I I don't know. Typically, don't wanna see more compliant tendons. That's not usually good. But we know that loading it under high force conditions is typically So it
Isaiah or Austin:all it all comes down to get way better at producing force, baby. I don't know about you guys, but I'm ready to train my ability to produce force very quickly.
John:Yeah. I think we're good. Yeah. That was interesting. Austin, any anything that you'd like to add as a as someone who is not formally trained in exercise physiology, but has been coaching for a while?
Isaiah or Austin:I know dude, I just wanna train, man. I'm like I'm I'm antsy. I've been antsy this whole time. I'm not gonna lie.
John:Austin hates me. Meditation, man.
Isaiah or Austin:You gotta you gotta observe the antsy.
John:Anyways, that's the podcast podcast, guys. Make sure you like, comment, and subscribe. If you are a physics nerd like we know our friend Sam is, make sure you leave any of your your comments and Ben as well.
Isaiah or Austin:We learn. We learn from the We comments
John:we think they're really interesting. If you guys have a useful piece of feedback or you're a biologist or physiologist, go ahead share it. I would be curious to know if there's something that you know we said that was incorrect. You know one of the things I'm I'm really curious about is you know that that point where the tendon deforms and it stores a lot of energy. I don't even know if we fully understand that so.
John:That all being what it is, we'll see you guys tomorrow.
Isaiah or Austin:Oh, and if you're on a podcast platform, five stars. Five stars. Please. Please. Please.
Isaiah or Austin:I beg of you.
