Subscribe
Share
Share
Embed
๐ง Takeaway: Donโt ignore shin splintsโthey're an early warning sign. Address hip control, pronation, and running loads to stay ahead of injury.
๐ก Practical Tip: Build a multifactorial plan tailored to your injury history, training volume, biomechanics, and personal preferences.
๐ Actionable Insight: Sprinting once a week can enhance your economyโeven if you're already highly trained.
Expand your running knowledge, identify running misconceptions and become a faster, healthier, SMARTER runner. Let Brodie Sharpe become your new running guide as he teaches you powerful injury insights from his many years as a physiotherapist while also interviewing the best running gurus in the world. This is ideal for injured runners & runners looking for injury prevention and elevated performance. So, take full advantage by starting at season 1 where Brodie teaches you THE TOP PRINCIPLES TO OVERCOME ANY RUNNING INJURY and letโs begin your run smarter journey.
:
On today's episode, we are looking at the latest running research. Welcome to the only podcast delivering and deciphering the latest running research to help you run smarter. My name is Brodie. I'm an online physiotherapist treating runners all over the world, but I'm also an advert runner who just like you have been through vicious injury cycles and when searching for answers, struggled to decipher between common myths and real evidence-based guidance. But this podcast is changing that. So join me as a run smarter scholar and raise your running IQ so we can break through the injury cycles and achieve running feats you never thought possible. Welcome back, Run Smarter Scholars. Hopefully you've had a nice Easter break. Speaking of, the audio quality might be a little bit different as I am in a new room because with the Easter break, I'm down at the beach. So new room, yet still recording an episode because the show must go on. In particular, this one I usually record on time. It's not something that I have pre-recorded because we're looking at the latest research. I have... weekly reminders and my inbox gets filled every Thursday looking at, what has been the latest in running research that has been released? And then I filter through, find what's interesting, add it to the list. And then at the end of every month, I see all the compiled research papers and pick three-ish depending on the length of them, three to four on what I think you might find the most interesting. I usually try to find one that's like injury prevention or running performance, but also some around musculoskeletal or running related injuries. Um, especially if the findings are particularly interesting. So they're like I say, the show must go on, even though I'm in a different room and I couldn't pre-record this one because of the way in which this episode is conducted. So I have picked three papers you might find particularly interesting. Uh, however, There are a ton that I have found this month. There's been about 15 papers, which are now all compiled into the April Google Drive, if you are a member and subscribe to the Run Smarter AI Assistant. You can then go now to the Google folder, go to April, you'll see all of those papers in there. But these are the three that I've picked out. The first one is to do with shin splints. Learning more about it, how can we prevent it? If we do have it, what are some strategies to overcome it? The title of this paper, was medial tibial stress syndrome, a scoping review of epidemiology by mechanics and risk factors. If you're not aware, medial tibial stress syndrome is just a fancy term to mean shin splints, medial meaning the inner border, the inside part of the tibia. So medial tibial stress syndrome, obviously indicating that there's been some sort of load or some sort of stress that is producing the symptoms. So let's go through this paper and see what insights we can have about this condition. If you do have it, how can we treat it? What are the risk factors so that we can mitigate or reduce risk of you getting it if we know more about it. So the abstract of the paper starts with medial tibial stress syndrome is a common overuse injury of the lower extremity. It involves exercise induced pain over the tibia and is an early stress injury in the continuum of tibial stress fractures. This scoping review aims to synthesize and characterize the literature on shin splints, identify knowledge gaps and propose future research directions. They're saying, I think it's now more common to describe shin splints as just very, very early signs of tibial stress, bone stress reactions, like a stress fracture. If you can imagine this particular condition or pathology on a continuum where we've got the very severe end being a full stress fracture, which we never want to see with runners. It's one of the most debilitating and frustrating injuries a runner could have. Then we have, that we go along that continuum to more of the minor side of things. First onset might end up being something that represents tibial stress syndrome, medial tibial stress syndrome. And if you ignore it and you continue to overload it, that pathology can continue. and then increase the likelihood of a stress fracture. So need to take this seriously. In the paper, there's a section on pathophysiology and it says the pathophysiology of shin splints remains to be elucidated. One hypothesis proposes that pain is attributed to periosteal inflammation resulting from excessive traction on either the tibialis posterior or the soleus muscle. So this would mean that as the muscles that attach onto the shin, one of them being the tibialis posterior and one of those muscles being the soleus muscle, which is one that makes up your calf, attached to the tibia, attached to the inner border of the tibia. And when they have, when they activate, when they produce this high amount of force, it creates traction on the bone that attaches to. And if that is too excessive, the outer layer of the bone called the periosteum starts to become inflamed. Then we have this periosteal inflammation resulting from excessive traction of these muscles that produces shin splints. This is one of the hypotheses that they've come up with. This concept is reinforced by bone scans, looking at bone scans and seeing that there is enhanced uptake along the periosteum. So the bone is undergoing some sort of reaction. Recent investigations in athletes with shin splints have demonstrated that it is primarily a bone overload injury. These investigations demonstrate a reduction in bone mineral density of the tibia at the site of the shin splints, which subsequently returned to baseline levels upon resolution of the shin splint symptoms. So we're looking at the bone is undergoing some sort of reaction. It's not just about the fascia or the soft tissue that connects onto the shin that's producing these symptoms. We're actually looking at the condition of the bone actually starts to change. We know this from bone scans. We know this from observing the bone mineral density that gets worse with shin splints, but then gets better when shin splints improves. When we look at the clinical presentation, this paper says that patients with shin splints frequently present with bilateral, I don't know about bilateral, but they say, with bilateral tibial aches on the medial side of the middle tibia. So we're looking at the inside border of the tibia and we're looking at sort of the middle section of the tibia, not all the way down at the ankle, not all the way up at the knee, sort of in the middle section. However, shin splints may affect the anterior, posterior or lateral sides of the leg. So it's typical in that area, but it can present in other areas too. Pain is induced by physical exertion. and alleviated by rest. It is commonly experienced at the onset of an activity and diminishes in magnitude as the exercise progresses. So it has this warmup effect, similar to what you would see with things like a tendinopathy. Pain intensity frequently increases the following morning. Again, sort of representing what we would see with a tendinopathy, although it may diminish over time. Resting pain is experienced in patients with extreme and persistent shin splints. So it can become so aggravated that even just lying down, sitting, not moving, still presents with symptoms. It is widely accepted that tenderness along the inner border spanning more than five centimeters is indicative of a diagnosis of shin splints, whereas tenderness spanning less than five centimeters. So we can say that's more focal, it's more like pinpoint type of pain. is indicative of a stress fracture. So shin splints along the inner border of the shin that is more widespread, spanning more than five centimetres would be more indicative of shin splints. Whereas if it's more consolidated and there's pain in the inner border that's more focal, that may be more indicative of stress fracture. Clinically, it is necessary to exclude other pathologies, including tendonitis, chronic exertional compartment syndrome, nerve impingement and popliteal artery entrapment. which warrant consideration when evaluating patients with shin splints. When looking at diagnostic studies, they say that x-rays can be useful to exclude stress fractures. So I guess we're not really looking at scans that can rule in shin splints, but we can definitely do scans that rule out stress fractures. They say a triple phase bone scan can elucidate the difference between stress fractures and shin splints. In recent years, imaging modalities have transitioned from a triple phase bone scan to an MRI because of the superior resolution provided by the MRI technology. Let's look at treatment. Various therapeutic interventions have been proposed for patients with shin splints, including rest, cryotherapy, which just means ice packs, stretching and strengthening exercises, shockwave therapy, stretching and strengthening exercises, graded running programs, gait retraining, lower leg braces, and injection therapies. Despite the increasing incidence of shin splints, research on its underlying mechanisms remain inadequate. Consequently, it is imperative to elucidate the mechanisms underlying shin splints to demonstrate appropriate prevention strategies based on risk factors and biomechanical disorders. Okay, so this is a scoping review. So they did go through a certain inclusion criteria trying to find all these other studies. looking at the epidemiology, looking at the biomechanics, looking at risk factors, compiling a whole bunch of things. They ended up finding, well, in their search, they found 1,827 records. And after removing duplicates, going through the title and abstract to try to find what's eligible, going through an eligibility criteria, they were finally left with 37 studies, which they included in this final inclusion criteria in this final scoping review analysis. when analyzing all the participants in these studies, they said that the vast majority of articles recruited athletes as study participants, followed by, well, they said that around about 68 % of all the populations in all these studies were athletes, followed by articles by military members, which is around about 16 % of all these people. So this isn't just runners, this isn't just athletes, this is combining a whole bunch of people in this scoping review. So just bear that in mind. Let's look at risk factors. They say in the younger age person, participants with shin splints had greater BMI values. So it seems to be like a higher body mass index when you sort of heavier people looking at the calculation of body mass compared to height. seem to be, people with higher BMI seem to have an increased risk of shin splints. Although a significant correlation between BMI and the time required to complete recovery was also established. So not only people with high BMI have a risk factor of shin splints, but if you do have a higher BMI and you have shin splints, also seems to take longer to recover. The findings of an American study indicated that those with greater experience in athletic activities are at a lower risk of developing shin splints later in their career. So if you've been relatively athletic in your youth and have a ton of experience in athletic activities seems like you are at lower risk. In contrast, a German study found that ultra marathon running increase the incidence of shin splints. And also they found that a history of shin splints is the strongest predictor of shin splint development. Kind of makes sense there. I think they find that with most musculoskeletal injuries, if you've had that particular musculoskeletal injury in the past. vastly increases the likelihood you're going to get it again. You just need to make sure you do be sensible. Additionally, athletes with a history of shin splints and stress fractures were significantly more prone to experience shin splints. So we need to factor in stress fractures in there as well. The combination of female sex, shin splint history and hip external rotation yielded a robust and accurate model of predicting the risk of developing shin splints in Navy recruits. They didn't, they say, and external rotation and hip external rotation. I'm assuming it means excessive. Like if you have a lot more hip external rotation than others, um, I would say, because everyone has hip external rotation. So yeah, that's how I'm interpreting it. So the combination of, you are female, if you have a history of shin splints, and if you have excessive hip external rotation, this is the combination that leads to the, uh, strong, strong. predictive risk of developing this. Runners who develop shin splints demonstrated a tighter ITB than uninjured runners. Take that for what you will. What about biomechanics? They said a study conducted in 2020 revealed that the shin splint group exhibited a higher peak EMG amplitude. So we're looking at the activation of muscles, particularly around the soleus muscle. And they say that this study the shin splint group had a higher soleus muscle activation than the control group however no significant difference was detected in the tibialis anterior muscle between the two groups so the tibialis anterior is the muscle in front of the shin if you lift your toes up and you feel your shin it's that muscle that tightens up and so when we go back to that initial hypothesis on the pathophysiology where we have the soleus muscle through high degree of force tugging on that bone that then elicits a bit of a reaction to the outer layer of the bone would make sense that if you do so happen to have a higher muscle activation of your soleus, it's going to be pulling on that tibia bone more. And if you are one of the people that does have a very, very high peak amplitude of this muscle activation, then it might increase your risk of shin splints, which the study seemed to find. Still on the topic of risk factors and biomechanics, they said that soccer players with a clinical picture of shin splints had abnormal structural foot deformation during the stance phase of running. They had higher amplitudes of angular change and translational motion of the medial longitudinal arch and the lateral longitudinal arch. So if you're standing, have this arch, most people are familiar with the arch of your foot and there's one that goes from your heel to your toe. There's one that goes from right to left. And so it seems like the, those two arches during your stance phase, when you start loading the structure, if that deforms more and seems to have this angular change, it seems like that let like the people who had shin splints did seem to have a greater change in those things. Researchers have shown that runners with shin splints experienced greater pressure on the medial than on the lateral aspect of their feet during initial contact, flat foot and heel off. So all the other phases of the gait cycle. Moreover, the percentage of body weight in the medial metatarsal region is significantly higher in patients with shin splints. So if I'm kind of just drawing all of these pieces together, another study found that the navicular drop test, so in your foot, one of the bones that's kind of around the arch of the foot, when you sit, it rests in a certain position. When you go to stand up, that navicular bone can drop down towards the floor, almost like a kind of collapsing of the arch, we can kind of call it. They showed that with the main navicular drop test, a score was significantly lower in the shin splint group than in the normal group. So like if I'm pasting all this together, it seems like more collapsing of the arch, more pronation, more angular movement of the arches seemed to be a pattern in the shin splint group when compared to the control group. It continues on a similar theme. It says that two significant discriminators were identified between the healthy and shin splint group, maximum pronation velocity and maximum pronation. So we're looking at the volume of the pronation, but also how quickly you move into pronation. They also reported a significant relationship between shin splints and the development of over pronated feet. So again, we're following that common theme in Australian study by mechanical evaluation revealed a greater foot pronation in the shin splint group. I think we'll get the point. I don't know why I highlighted all these points. They all sort of lead to the same thing. Moving further up the chain, an analysis of injured runners demonstrated the greater contralateral pelvic drop and forward trunk leaning at mid stance was identified in the shin splint group. So if we're looking at that, we have contralateral hip drop. So if you are running and you land on your right foot and your right foot is we're in the phase of the cycle where your right foot is directly underneath you. If your left hip is traveling more towards the ground, that is a contralateral opposite side pelvic drop. So if that elicits, if that is identified in a runner and also a forward trunk lean, so if your posture and your chest is a bit more angled forward and leaning forward, and that seemed to be evident in a shin splint group. But they also said that hip adduction was greater among subgroups of runners with shin splints. So hip adduction is when you're running. So we plant our right foot, that right foot is underneath us. Our right knee is traveling more towards the midline. So there's this angular pointing in of the knee on the stance leg, pointing more towards the midline. Individuals with shin splints displayed a weakness in their hip abductors as compared with healthy runners. So we're looking more at the chain around the hips now. We're seeing that the hips might be a little bit weak. There might be a loss of control where the opposite side opposite hip drops down towards the floor. That means that the stand on the stand side, those glutes might be weak. But also that weakness might also lead to the knee caving in. So we're getting a picture of that. Unfortunately, this paper doesn't go heavy on the treatment side of things, but I think with some deductive reasoning, we can sort of come up with some treatments ourselves based on the risk factors. They did say that the authors extrapolated that amplified dynamic foot pronation might augment tibial strain by increasing the peak soleus muscle activity. This phenomenon could potentially lead to overuse and subsequent development of shin splints. if the amplified strain surpasses the structural capacity of the tibial bone. So it's good that they mentioned that we're talking about load versus capacity. This is the underpinnings of this podcast. We know that running is okay. We know that pronation is okay. We know that a little bit of imperfect running mechanics is okay, but we just want to make sure that what we put our body through doesn't exceed its capacity to adapt. If it does exceed the capacity to adapt, it starts getting sore. So what they're saying here is that, yes, we could augment tibial strain. If there's something that we could do, if there is a pronation component to it, if there is a hip drop component to it, a knee caving in, you may be putting more stress on your tibia than someone who doesn't have those things. However, you can still have those things and not get shin splints if you don't train within certain loads that exceed that capacity anyway. you might be more likely to exceed those capacities if you do elicit those traits, but you can still train safely and still not develop shin splints if you're training sensibly. So there's a combination of those things. It may be hypothesized that runners may derive benefits from the adjustment of dynamic foot pronation through the utilization of arch support or orthoses potentially mitigating tibial strain. So if we do have an individual, that elicits these traits, elicits the foot posture stuff and the hip drops and the knee caving in, and they're constantly getting shin splints and they're really struggling to return to running without developing these symptoms. It's hypothesized that yes, if we do provide some arch support, let's at least trial them onto arch support and let's see if things improve. That's just a hypothesis. They're not really drawing any conclusions from any studies, but that's just one thing that they mentioned. However, I would say, When looking at these studies, it seems to be important that hip strength should be a focus. If you are weaker in your hips and you do have shin splints, doing some strengthening of the hip muscles, I like to do hip hikes. Sometimes I like to do crab walks, resisted side stepping. However, you know, that can only load up to a certain degree. Whereas with hip hitches or hip hikes, you can load it up quite nicely and really get the glute medius strength. building up quite a lot. If we do have someone that has a crossover step width, we can widen that step width because that will decrease their amount of pronation and also the velocity of their pronation. We can look at footwear, we can look at some more stability shoes if the individual finds that comfortable. We can look at a walk run strategy to return to higher volumes of running, but we find typically a walk run schedule works particularly well. There's just things I've found that have been effective. might throw that in there. Cause like I say, the, this research paper doesn't really hit the mark in terms of treatment strategies. The next article I want to go through is around injury prevention. And for you members who are part of the AI assistant and my Google drive, I highly recommend you go to this paper and look at all these visuals. Cause it's quite beautiful. All the hard work they've put into these interventions to reduce your risk of injury and all of these multifactorial directions. all the directions that could be taken to reduce your risk of injury. They've gone into a lot of extensive work on this and it can be a bit more clearly demonstrated visually than me just talking about it. But let's go through it anyway. The title of the paper is Running Centred Injury Prevention Support, a Scoping Review on Current Injury Risk Reduction Practices for Runners. Let's go through the introduction. They say, Current injury risk reduction strategies for runners have had a variable impact on reducing overall running related injuries, with the incidence of injuries still higher than in most sports. We do know that running recreational running, marathon trainings, all that sort of stuff's very, very risky where we have fallen out. We have built a love for a sport that is very, very risky. Spare that in mind. Risk factors for running related injuries include relationships between runners health, biomechanics, physical conditioning, running environment and training habits, current and previous experience and behaviors. This range of influence poses difficulties in determining an approach to injury risk reduction practices where running related injuries are predominantly overuse. And the etiology of injury follows a causal framework where loading alone cannot be responsible for injury without considering an interplay of other factors of the runner's capacity for load. This is why when we talk about reducing risk of injury, we say, yeah, it's very multifactorial. We're not just looking at training loads. Yes, we are looking at the loads on your body. We're also looking at your body's ability to tolerate that load. So we're looking at the capacity and your recovery strategies, but then we're also looking at so many other things such as like overall general health, biomechanics, terrain. All that sort of stuff. There's so many things that come into this. The paper says additionally, runners have personalized responses to perception of pain or views on risk, which are both dependent on multiple influences characterized by current understanding of biomechanics and the psychos, the biopsychosocial models of pain. Therefore may struggle to interpret and respond to symptoms. Sort of like if you have symptoms, is an injury, is it not? I don't know. Should I do something about it? Probably not. Like all of these things go through our minds all the time. Exercise based injury prevention programs in particular have been highly successful across a range of sports and are effective at reducing the risk of injury on average by 29%. But generally not found effective if delivered in an unsupervised intervention. So this is when we're talking about just general sports across whole range of sports. you implement an intervention that reduces people's risk of injury. It tends to be very successful up to 29 where about a third of injuries are prevented. However, it doesn't seem to be that effective in the unsupervised with unsupervised interventions. That's pretty much recreational running. Very few runners actually have a coach. Very few runners have a team that, you know, consistently get together, do weekly drills, do weekly race preps, do weekly strength training, stretching, all that sort of stuff. You know, it's essentially like a do your own thing type of sport that we've signed up for. And so I guess that's one of the reasons why runners get so injured. say that studies have found a lack of conclusive evidence for the effectiveness of injury prevention programs designed to address risk factors in runners and endurance runners and for knee injuries. They're talking about three different papers that they found there. The majority of supervised intervention plans are in team sports where the training environment is supervised by coaches who can influence team participation in the programs and enhance compliance with injury risk reduction practices. Runners participating in differing environments with individual risk profiles, abilities, running goals and beliefs may make universal injury risk reduction interventions more difficult and more difficult to disseminate and adhere to. Despite this growing body of research, utilizing strategies other than intervention programs, there has not been a reduction in running related injuries like the results seen in other sports. With over half of the runners reporting a running related injury in a recent survey conducted over a 18 month period in 87 countries. So if we follow runners for 18 months, every other runner reports an injury in that period of time. That's huge. It's a huge risk when we do the sport that we love. This scoping review aimed to collate literature on injury prevention strategies used with runners to establish the types of interventions which have been implemented or discussed in the literature to reduce the risk of injury. A secondary aim sought to explore how these strategies have delivered to a and received by runners and what views other stakeholders and experts consider as best practices. It's not only are they going out and seeing what interventions are the best, but they're also going out and seeing what the runners adhere to, what do runners perceive as better, how are they delivered, and what are the experts and coaches thinking. Okay, the results. Like I say, this is a scoping review, another one. So I like talking through these numbers. They through their... criteria, they identified 3,470 potential articles. And then again, they have to remove duplicates, they have to go through the titles and abstracts, they have to go through the inclusion criteria, see what's eligible. A total of 99 studies were eligible for this particular review. They're going to different types and different subsections of this. And I've only just highlighted a few. It is very extensive, like I say, if you do have access to this, go check it out. Visually, it will explain it quite nicely. But one of the subsections was the types of interventions and methods delivered for injury reduction in runners. In brief, interventions either included some level of supervision or digital support from the project teams or the participants self-managed with minimum face-to-face interaction or remote support. When it comes to the opinions from experts and best practices, they found that six themes were identified that to reduce risk of injury, that being gate re-education, just meaning like re-training, identifying re-training running technique, training and loading. So we're looking at the programs themselves, like the weekly volume and intensities and that sort of stuff to reduce risk. Footwear was another section, strength training, general education and advice on recovery were the main sub-themes. Overall, most studies advocated a multifactorial approach of more than one strategy to reduce the likelihood of running related injuries. I would say that's fair. We want to control the loads. We want to control if there's any real obvious insufficiencies in your running. We also want to see when you put your body through load, can we enhance your recovery to avoid an overuse injury? Okay. Practically. What did this paper find? Number one, supervised programs work better. I sort of talked about this initially, exercise-based injury prevention programs only consistently reduced injuries when supervised. Unsupervised programs, even with the same content, showed little or no effect. That's an interesting finding. Number two, strength training reduces risk when done right. Strength training was one of the most researched strategies and is effective Especially when tailored and supervised programs, including resistance and neuromuscular training showed significant injury reduction. Number three, gait retraining shows promise. Real-time gait retraining via wearables and supervised feedback reduced injury rates by up to 62 % in some studies. Expert reviews support this as a key area of injury prevention, particularly for runners with high vertical load or poor cadence. So if someone is hitting the ground quite hard or if someone has a cadence that's outside of their optimal, working on those particular factors seems to be promising. Number four, runners prefer passive easy strategies. No surprises there. Many runners opt for strategies with minimal disruption to their routine, such as shoe changes or using wearables. These are perceived as easier to adopt compared to strength programs or gait retraining, highlighting the gap between expert advice and runner behavior. Footwear matters, but it's personal. This is number five. Footwear interventions didn't show consistent injury reduction across all runners, but motion control shoes helped runners with pronation, but minimalist shoes were better tolerated by runners with prior injury experience or light body weights. Shoe type effectiveness depends heavily on individual profiles. Number six, recovery is underrated but essential. Experts emphasise that recovery strategies are crucial yet under discussed in the literature. Simple changes like sleep hygiene, rest days and stress management may offer impactful low effort ways to lower injury risk. Number seven, Runners respond better when informed, providing education with a clear purpose and benefit improves engagement. Generic advice is less effective than tailored content, explaining the why behind the strategy, especially when delivered by coaches or trusted professionals. Number eight, coach and group support change outcomes. Runners benefit from supervised coached environments even when Informal, peer support, feedback and structured progression help translate knowledge into action and improve adherence to injury prevention programs. And lastly, number nine, there's no one size fits all. Experts recommend a multifactorial and individualized approach, combining strategies such as strength, footwear, recovery, tailored to the injury, the runner's injury history, goals and lifestyle, which is more likely to reduce their injury risk. for a single compared to a single intervention. Definitely fair to say, we definitely want to look at a runner's injury history because if someone has no history of calf strains and instead has a long history of hip flexor issues, we'd tailor the strength, we'd tailor the footwear, we'd tailor how they run, we'd tailor the terrain because those two profiles may be completely different. I found a nice practical paper if someone wants to improve their Running Economy. The title was the effects of intermittent sprint training on running economy and leg stiffness in highly trained runners. In terms of the group, they had 25 participants. There were highly trained runners. There was 12 male and 13 females in this study. In the introduction, they said for years, VO2Max was considered one of, if not the sole, major contributor to running performance. While VO2max is still vital, running economy has been described to be a more accurate predictor for running performance. Running economy is defined as the energy demand required to run at a constant submaximal velocity. If can think of it, I've done previous episodes on running economy before, but... How efficient are you at moving at sub maximal speeds? We're not talking about sprints. We're talking about sort of marathon paces and those sorts of things. How effectively can you move through space? How effectively can you utilize oxygen? How much oxygen do you require? How effortful is it? All of these things influence or factor in your running economy. They say changes in training can influence running economy by modulating one or more of metabolic, cardiorespiratory, biomechanical or neuromuscular efficiency. Of the many different training modalities, sprint training has been postulated to improve running economy through improvements in biomechanical and neuromuscular efficiency. So if we are subjecting our body to high speeds, we are stimulating the nervous system to stiffen up our muscles, run more biomechanically efficient and adapting to those conditions so that when we drop the speed, we're more efficient. Our nerves are firing to our muscles in a better pattern, in a better firing pattern and contributing to efficiency. Several studies have investigated the relationship between sprint training and running economy with several investigations showing positive performance results while work has been done. correlating sprint training on improvement in running economy in moderately trained athletes. No prospective study has demonstrated positive change in running economy secondary to sprint training protocols in highly trained athletes. Sprint training is hypothesized to impact running economy by modulating biomechanical and neuromuscular efficiency. They've put that in twice. Don't know why I said it twice. Biomechanical and neuromuscular efficiency. are influenced by many variables of which leg stiffness was one particular interest by the authors. Leg stiffness is a measure of how rigid the plant leg is during the gate phase with higher stiffness shown to be correlated with improved running economy. So we're looking at less moving parts. If you are planting on the ground and pushing off and you're doing that with a low degree of movement, then there's energy expenditure, there's less energy cost, and it could be converted more into forward propulsion instead of absorbing and wasting a lot of energy, you could say. As a spring becomes stiffer, it is capable of storing more potential energy during the stance phase that can be converted into kinetic energy during the propulsion phase of the gait cycle. Takes me back to my days of year 12 physics when we're talking about potential energy and kinetic energy, but we're converting these two energies and We can store the energy better if there's less moving parts and then convert that into forward momentum or power As if it is more stored if we had more stored energy Okay, so the participants in this study they were eligible if they were between the ages of 15 and 40 years old They had no current or past cardio I don't that is, but for those who are into the athletics, that would probably be a big deal if I'd know their trying to weave out all of the moderately trained runners and only get these highly trained runners. Okay, the protocol of the study participants completed a 10 minute warmup at their chosen speed on a treadmill. This chosen speed needed to be slower than 70 % of their reported 10K pace. Upon completion of the warmup, participants then stepped off the treadmill and were fitted with a VO2 mask, not fitted with a whole bunch of other. technology to look at their movements. And then they completed three interval running stages. Stage one consisted of running at 70 % of their 10k pace. Stage two was 80 % of their 10k pace and stage three was 90 % of their 10k pace. And then they analyzed their stiffness, analyzed their biomechanics, they analyzed how efficient they were in their running economy and how much oxygen they were converting and using up. at those different paces. All right. After that baseline testing, they then went through a 12 week sprint training program where they did one sprint session once a week. So only one, only once a week for 12 weeks. The intervention was a 12 week protocol of sprint workouts developed by the authors and incorporated into each participant's own standard endurance exercise regime. Throughout the course of the intervention period, the length of the sprints increased. However, the intensity of each sprint was equal. So the effort that they're putting in, the intensity of each sprint was the same. However, those sprints just became longer and longer as the weeks went on. If you have access to this paper, then you can have a look at all the sprints that were done, followed by the rest periods. But let me just throw an example, week one. was doing six rounds of 30 meter sprints. So you would call that the reps. So six by 30 meters was the reps. They did two sets of those, followed by three to four minutes between sets. Let me try to explain that a bit better. So I guess set one was doing six repets of 30 meters. where in between every 30 meter sprint, there was a two minute rest. And then they went and rested for three to four minutes and then did that same session over again. It's where these visuals come in. But we can just keep getting bigger and bigger, longer and longer durations, say at week six. We have up to 50 meters now and we're doing five rounds of that. So you do a 50 meter sprint. You rest for two minutes and you do that five times, rest for four minutes and then you do that whole session all over again. Week 12 is a bit more complex. We've got two by 60 meters, two by 80 meters and two by 100 meter sprints. And in between each of those was a three minute rest and in between each set. So every time we increase the duration of the sprint. we increase the recipe was four minutes. Let's go through the results. Result number one, sprint training may improve running economy even in elites. Although not statistically significant, 68 % of runners showed an improvement in running economy after just one sprint session per week for 12 weeks. That means you may become a more efficient runner, burning less energy at the same speed by adding short sharp sprints. Number two, leg stiffness significantly improved. Leg stiffness, a known contributor to better running economy and performance, increased by 12 to 17 % across all tested speeds. This means more spring in your stride and less wasted vertical movement. Number three, less bouncing equals more efficient running. Vertical displacement of the center of mass decreased by 15 to 18%, reducing the energy need to lift your body up each step. This was the key driver behind improved leg stiffness in directly running economy. Number four, biomechanical efficiency trumps cardio in running economy gains. While VO2 max is important, running economy is a better predictor of performance, especially for well-trained runners. Sprint training likely improved musculoskeletal coordination and mechanical patterns, not just cardiovascular fitness. Number five, higher volume runners benefited most. Participants who logged more total training hours during the study saw greater improvements in running economy and leg stiffness. So if you're already running decent mileage, sprinting might give you a better performance boost. Number six, benefits apply to both genders and age groups. Improvements are seen in both males and females and in runners above and below the age of 30. making this protocol accessible for a wide range of athletes. And lastly, number seven, just once a week is enough. A single sprint session per week lasting around 10 to 20 minutes was all it took to produce meaningful biomechanical change, perfect for busy runners who can't commit to more volume. Members, if you are a part of this AI assistant and Google Drive, go check out that folder now. You will see the papers I've discussed here. However, when it comes to the performance side of things, you'll find a study that says unveiling the psychological traits of multi marathoners, insights from TIPI personality trait analysis. If we're looking at rehab, I found a paper on platelet rich plasma treatment for Achilles tendinopathy, a systematic review and meta analysis for that. I found one that looked at successful return to sport following non-operative treatment for proximal hamstring tendinopathy. Physio management for gluteal tendinopathy. Again, there's a shin splints one in there. Also a paper on tarsal tunnel syndrome in runners. That's a condition of the, around the ankle or the foot. When it comes to biomechanics, I found one on optimizing. The title was optimizing running mechanics, effects of cadence footwear and orthosis on force distribution. A few that I put in the others bucket. There was one that was titled. Personalised nutrition for the enhancement of elite athletic performance. That was one that almost made it to the cut of this episode. lastly, exploring molecular and cellular signalling pathways, unraveling the pathogenesis of tendinopathy. That one was a very, very interesting read. If you're interested in tendinopathy, go check that one out too. Thanks for tuning in for this latest running research episode. I'll be back next month with a similar structure. As always, thanks for joining me. and good luck with your running this week. Thanks once again for joining me and well done on prioritizing your running wisdom.