The Strength Exercises That Help Tendon Pain Without Stretching

Ahead of the Chicago Marathon, Clayton Young shared that he tore his hamstring, but still planned to compete. One of the strategies he said he used to get to the starting line and, ultimately, to the finish line as the first American: abandoning stretching in lieu of strength work—namely, isometric exercises.When I heard this, I realized I had something in common with Young. My physical therapist, James Chung, PT, DPT, a sports performance physical therapist based in New York City, also recommends doing isometric strength exercises to deal with tendon issues, including my Achilles tendinopathy.Isometrics are, indeed, great for pretty much everyone, says Mandy Fox, DPT, a physical therapist for runners in New York City. “An isometric exercise is a muscle contraction where the muscle produces force, but it doesn't change length and the joint angle doesn’t change,” Fox explains.Basically, you’re loading the muscle and then holding it in one position for a set amount of time, like 30 seconds, as you would do in, say, a plank hold. This is in contrast to a concentric exercise, like lifting weights up to the top of a biceps curl, or an eccentric exercise, like slowly lowering heels down in a calf raise.Whether you’re dealing with a hamstring tendon issue like Clayton, an Achilles tendon issue like me, or even a hip/glute tendon issue, this type of exercise can help. “This works because across the board, whether you’re elite or amateur, tendons respond to load, but they don’t respond to lengthening,” Fox says, adding that doing isometrics helps you keep running when you’re dealing with tendon issues.While it’s always best to get evaluated by a doctor or physical therapist to rule out other factors that require a different approach, you can see a few common clues below that might point to a tendon-related injury and how isometrics can help.In fact, even if you’re totally healthy (enjoy it!), these exercises still offer benefits, says Chung. Here’s how they work in the defense against running injuries, plus specific exercises to try, and how to add them to your routine.How to Know If You’re Dealing With a Tendon IssueFor one, tendon pain is typically closer to where the joints are, says Chung, so you may feel Achilles tendon pain closer to the ankle and hamstring tendon issues at the sit bone or either side of the knee.On the other hand, you’ll typically feel muscle strains or tears where the muscle contracts (and you feel pain when that happens). For example, with a calf strain, you might feel it most when you push off the ground, or with a hamstring strain, you might feel it most when your knee extends during the late swing phase of the gait cycle. You will also feel pain when you stretch a strained muscle.Another way to tell: “Tendon pain is kind of dull and achy depending on what stage you’re in, but tendons will have what’s called a warmup effect where you’ll actually feel better when you warm it up,” Chung says, like after your first mile or two.Why Isometrics Work—and HowIsometrics do a few great things for runners, Fox and Chung say.First of all, they can help with bloodflow to the tendon. “The sustained contraction is going to squeeze your local blood vessels, and when you release the contraction, you get blood flow back into the area,” Fox says. She adds that tendons are inherently “poorly” vascularized, because they are made up of a type of collagen fiber that’s unique from muscle tissue, which is why they can take a while to heal. “Basically it’s helping provide more circulation, more nutrients, more oxygen to the area to support tissue recovery.”For example, if you hold a single-leg glute bridge with your heel pressing into the floor for 30 seconds and then release the hold, the sustained contraction squeezes the blood vessels within the hamstring muscle group and then blood rushes back into the muscles on the release, Fox says.Second, isometrics may help muscles work more efficiently. When you’re injured, pain can interfere with the signals your nervous system sends to your muscles, making it harder to activate them effectively. By contracting a muscle without moving the joint, isometrics can help restore that communication without aggravating the injured area, Fox says. You basically train the nervous system to recruit more motor units in the muscle that drives the tendon and teach it that it’s “safe” to move.By improving this communication, isometrics can also help tendons repair and remodel, so they’re more equipped to handle the load of running, Chung adds.When it comes to tendon injuries, complete rest isn’t necessarily the answer, and neither is stretching. “Tendons are not that pliable; you want them stiff so they can transfer the force of the muscle through the joint to create that movement,” Chung says.The final benefit of isometrics has to do with more immediate pain management because these exercises can have a pain-reducing or an “analgesic” effect. “Doing sustained isometrics can actually produce a short-term drop in tendon pain that can last 30 to 45 minutes or even up to a couple of hours, which is why sometimes we use them before a run,” Fox says, or at the start of a PT strength session. Chung says it’s similar to when you rub your skin when you bump it to reduce the pain.How to Work Isometrics Into Your RoutineThe more you do isometrics, the better, so aim for daily. “More frequent exposure is better because then you normalize that and you can build more over time,” Chung says. “Because there’s not much lengthening happening, you’re less likely to induce soreness from it, which is why you can do isometrics very consistently.”As for when to fit these moves into your schedule:Prerun: Fox has clients do two to three sets of 15- or 30-second holds of a bodyweight exercise as part of their warmup. “If you’re doing a couple of bridge holds or calf raise holds before a run, it can really wake up your glutes, your hamstrings, your calves,” Fox says.On strength days: Fox and Chung both have runners do weighted exercises as part of their lifting workouts. For example, someone might add one or more of the weighted exercises below for three sets of 30 to 45 seconds.Chung, too, likes to get runners to add weight as a way to progress these moves. “Tendons respond the best to being loaded really aggressively if they're healthy,” Chung says, and even if you’re currently injured, your goal is to get them healthy. This is why he prefers using machines for isos, because they provide an easy and trackable way to add weight over time.As far as how quickly you might start to benefit from these, in general, if you don’t have a recurring issue and the tendon pain has only been happening for a few days or so, you’ll likely start to notice some improvement within a week up to three weeks, Fox says. If you’re dealing with chronic tendinopathy, it’ll likely take closer to six to 12 weeks to see the true strengthening and alignment of the fibers to change, she says.One more fun fact: There are actually two types of “isos” you may hear about—yielding and overcoming. The latter is where you push into something that doesn’t move, Chung says. For example, you could try to pick up a barbell loaded with enough plates that it won’t come off the ground no matter how hard you try. The downside of these, Chung says, is they’re harder to measure and track the weight you’re using to make sure you’re progressing.In a yielding iso, you hold a position against a load, like the top of a calf raise or single-leg hamstring bridge. Fox says this is usually where she starts people. Chung likes these, too, because you can also progress them with machines at the gym that make them easy to set up and track (based on how much weight you’re using).The Best Isometric Exercises for Commonly Injured Tendons in RunnersHamstring Tendon: Achilles Tendon: Glute Tendons (including those that attach to the gluteus medius and minimus and the hip):