Do Strong Feet Reduce Injuries?
Plus—Fascial flossing for recovery; predicting 10k times with blood biomarkers, RPE vs. training load; hydrogel technology; and biomechanics of experienced vs. novice runners.
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Do Stronger Feet Reduce Injuries?
If a muscle is weak, you strengthen it, and the injury risk goes down. That logic is clean, intuitive, and honestly pretty satisfying. It also fits with a lot of the recent attention on foot strength in runners. But do runners who get injured actually have weaker feet to begin with?
A new study suggests the answer may be no, or at least not in the simple way many people assume.
The researchers looked at 225 runners, all of whom completed a questionnaire about their running-related injuries over the previous year. The researchers compared runners with and without a history of injury. They assessed foot morphology, maximal strength of the ankle plantar flexors, hallux flexors, and lesser toe flexors (muscles in the feet and ankle). They also looked at footstrike pattern and cadence during a self-paced treadmill run.
Runners with and without a history of overuse running injury did not differ in foot-ankle muscle strength. That was true for injury history in general, and it was also true when the researchers looked specifically at foot injuries. In other words, the runners who had been injured did not show obviously weaker toe or foot muscles than those who hadn’t been injured.
Faster runners were 51% more likely to report a history of overuse foot injury. That is not especially shocking when you think about it. Faster runners often train harder, race more, and put more overall stress through the foot and ankle. Higher performance can come with higher mechanical cost.
Runners with a history of tibia injury were less experienced and had lower cadence, fitting with the idea that newer runners may be less adapted to repetitive loading, and that cadence may matter more for some injury patterns than isolated foot strength does.
What this means for runners
Foot exercises may still be worth doing, especially because previous intervention work suggests they can help, but this study suggests that weak foot muscles alone are probably not the main thing distinguishing injured from uninjured runners. I think the more practical signal here is that injury risk likely sits in the interaction between training load, experience, mechanics, and tissue capacity. Faster runners may accumulate more foot stress, and less experienced runners with lower cadence may be more vulnerable to tibial issues. So rather than treating toe strength as the whole answer, I’d view it as one small piece of a much larger injury-prevention puzzle.
Does Fascial Flossing Help Recovery?
Recovery tools in running usually live in one of two categories: things that clearly help, and things that mostly survive on what we’ll call “vibes.” Fascial flossing has spent a lot of time in the second category. You’ve probably seen it before—a thick elastic band wrapped tightly around a calf or ankle, usually followed by heel raises or mobility work, with the promise that it will loosen things up and get you feeling springier again. The question is whether that feeling is real or whether it is just another recovery ritual that looks convincing. A new study tried to answer that.
The researchers recruited 17 nationally competitive male collegiate distance runners. Each runner completed a treadmill fatigue protocol that lasted 32 minutes, progressing from 6–10 mph (10 to 16 km/h), and then had one lower leg randomly assigned to receive fascial flossing while the other leg served as the control that didn’t receive the treatment. The flossing intervention involved a band wrapped around the lower leg while the runners performed heel raises and a short seated movement sequence (see below). Before and after the intervention, the researchers measured ankle dorsiflexion with a weight-bearing lunge test, perceived lower-leg tightness, reactive strength index from repeated jumps, and, most interestingly, myofascial gliding using ultrasound. Here, the researchers were trying to see whether the fascia and muscle were moving more independently after flossing.
After the intervention, gliding improved in the flossed leg but not in the control leg. That was one of the clearest findings in the study.
The range-of-motion results were also favorable. Both legs improved in ankle dorsiflexion after the treadmill run and intervention period, but the flossed leg improved more. That suggests some of the gain may have come from the general warm tissue effect of running and moving around, but flossing added something extra on top.
The control leg showed a drop in reactive strength index after the fatiguing run, which is exactly what you would expect when the lower leg is a little fatigued. The flossed leg did not. Its reactive strength index essentially held steady. This hints that flossing might help you keep some pop in the legs when fatigue would otherwise drag it down. Muscle tightness also improved (decreased) in the flossed leg compared to the control leg.
What this means for runners
For runners, I would interpret this as a cautiously positive result for flossing as a short-term recovery tool, especially after hard sessions when the calves and lower legs feel tight, stale, or a little dead. The most useful takeaway is not that flossing is some miracle mobility hack, but that it may modestly improve ankle range of motion, improve fascial glide, and help preserve lower-leg stiffness and spring after fatigue. That could make it a worthwhile between-session tool or even something to use before a second workout later in the day.
A Protein in Your Blood Can Predict Your 10k Time
There is always a certain allure to blood biomarkers in endurance sports. They promise to tell us something deeper than pace, heart rate, or even VO2 max. Maybe they can reveal the hidden physiology behind why one runner turns fitness into performance better than another. Maybe they can sharpen race prediction beyond what a field test can do on its own. That is the idea behind a new study, and I’ll admit, it is a compelling one. Because most runners have had the experience of running a solid workout or test, plugging the number into a calculator, and still feeling like the prediction misses something important. Maybe adding some more data into the equation could improve its ability to predict future performance.
This was a proof-of-concept study in 33 runners, mostly recreational but with a wide mix of backgrounds. They completed a 2.4-kilometer Cooper test on an outdoor track, and the researchers took blood samples before the warm-up and again within 10 minutes after the test. They looked at four non-conventional biomarkers:
Decorin - Think of decorin as part of your body’s structural support system. It’s a protein found in connective tissue (like tendons, ligaments, and muscle) that helps organize and strengthen the “scaffolding” around your muscles. Higher levels may reflect better tissue resilience—basically, how well your body can handle the pounding of running.
Hypoxanthine - This is a byproduct of energy use. When your muscles are working hard and burning through energy (ATP), hypoxanthine levels rise. So you can think of it as a marker of how much metabolic stress your body is under during hard exercise.
NT-proBNP - This one comes from the heart. It’s released when the heart muscle is under stress or strain, especially when it’s working hard to pump blood. In clinical settings, it’s used to assess heart health, but in exercise, it can reflect how much cardiovascular load you’re putting on your system.
BDNF (Brain-Derived Neurotrophic Factor) - This is often called a “brain health” molecule. It supports brain function, learning, and adaptation, and it tends to increase with exercise. You can think of it as part of why running can improve mood, focus, and mental resilience.
Then, two weeks later, 24 of those runners completed an official 10k race, which gave the researchers a real-world performance outcome to compare against the blood data and the Cooper test results. The main question was simple: do these biomarkers tell us anything useful that a standard field test does not?
The first answer was yes, at least in the sense that the Cooper test clearly moved the biology. Decorin, hypoxanthine, and BDNF all rose significantly after the test, while NT-proBNP did not. So the test was hard enough to trigger measurable musculoskeletal, metabolic, and neurobiological responses, but apparently not enough to make NT-proBNP rise.
But the more important question is whether any of that mattered for performance. Here, decorin separated itself from the pack. Higher post-test decorin was associated with faster Cooper test times, and both baseline and post-test decorin were associated with faster 10k race times two weeks later. Hypoxanthine also tracked with better Cooper test performance, but not with 10k race time. BDNF rose after the test, but it did not seem to tell us much about who would actually race better. NT-proBNP was basically a non-factor. So while several markers responded to hard running, decorin was the only one that looked even remotely useful for predicting actual endurance performance.
The Cooper test was already a good predictor of performance on its own—it predicted 10k race time with an average error of 1.92 minutes. Adding body mass index (BMI) improved that to 1.77 minutes. Adding post-test decorin improved it a bit more, down to 1.69 minutes. So yes, decorin improved prediction. But the gain was small. We are talking about shaving prediction error by seconds, not uncovering some revolutionary new way to forecast race performance.
What this means for runners
This is not a cue to go get your decorin measured after your next Cooper test. The improvement in race prediction was too small, and this was still a proof-of-concept study using estimated rather than directly measured VO2 max. But I do think the study reinforces an important point that performance is not just about your aerobic engine. There is probably a meaningful layer of “musculoskeletal readiness” or running economy sitting underneath race outcomes, and that may help explain why some runners outperform their lab-style predictions while others do not.
