February 29, 2024

How to Change Your Pace, Stride, Or Hill Training To Reduce Injuries

All running is not the same. For example, you’ve got fast running and slow running. You’ve got uphill running and downhill running. You’ve got short strides and long strides. 

And all of these make a difference, particularly in terms of tissue-loading forces across three main parts of the leg: the knee, the shin (tibia), and the Achilles tendon. If you knew how to change damaging forces at these key areas, you could minimize injuries, or enhance recovery.

And now, thanks to this new study, you do know. For the past year, I’ve been impressed by the research efforts of a young Dutch sports scientist named Bas van Hooren. He’s a top 10K runner himself. As a result, he thinks like a runner, and organizes studies designed to resolve important runner-related issues. 

In this case, he investigated what he calls “cumulative damage” (tissue-loading forces) at three common runner injury locations--the knee, shin, and Achilles. And he assessed this damage according to speed, incline/decline, and stride frequency.

Van Hooren did this with 19 runners who were tested on a lab treadmill at 5 different running speeds (9:40 pace/mile to 5:20), four gradients (-6 to + 6 degrees), and three different stride frequencies (normal, and plus or minus 10 percent). The standard damage condition was set at 8:00 pace on a level treadmill.

Result: 1) A high stride frequency reduced damage at all three locations. 2) A faster pace increased damage at the knee primarily, and also to a lesser degree at the shin and Achilles. 3) Uphill running increased shin and Achilles damage, but decreased knee damage. 4) Downhill running increased knee damage, but decreased shin and Achilles damage.

Conclusion: It seems smart to maintain a relatively short stride at all times to keep cumulative damage low. If you have shin or Achilles pain, avoid uphill running. If you have knee pain, avoid downhill running and speedwork. More at Scandinavian J of Medicine & Science in Sports with free full text.

Caffeine Gum Improves 5K Performance

Humans have long consumed caffeine through coffee and other beverages. At modern drug stores, we can now purchase more precise quantities of caffeine in pill form. Caffeine is both a legal and effective way to improve endurance performance.

Recently, caffeine-containing gums have reached the marketplace. They’re convenient, and enter the bloodstream rapidly, due to absorption through mouth tissues. But do they help you run faster?

To find out, British researchers conducted a randomized, cross-over trial with participants in a weekend 5K Park Run. They called it “the first study to investigate the effect of caffeine on the performance of recreational runners completing mass participation running events.”

Result: The caffeinated gum, which claimed to release 300 kg of caffeine per use, helped the runners finish 17 seconds faster (a 1.3% improvement) than a placebo gum. Subjects also reported a lower relative perceived exertion with the caffeine gum. 

Conclusion: “This is comparable with the 1.0–2.0% improvements observed in field studies and race simulations after supplementation with 3 to 5 mg·kg−1 of caffeine.” More at European J of Nutrition with free full text. 

So You’ve Gotten In Good Shape. Now What?

Here’s a paper that digs into a question every runner faces at one point or another. You’ve been training consistently for a while. Things are going well, and you feel pretty fit. Now what? What should I do next?

Specifically, you’re probably asking yourself this question: Should I continue with the same steady, continuous training, or is it time to add speedwork?

Good question. And here’s the answer according to the latest research: Do the speedwork.

Researchers arrived at this conclusion after first placing a large number of “young healthy participants” (ie, not serious runners) into one of 6 training groups. The 6 groups: a control group (non training); a continuous moderate training group; a continuous low-heavy intensity group; a continuous high-heavy group; a group that did HIT intervals for 4 minutes; and a sprint interval group. Subjects did 3 sessions per week for 6 weeks. 

Which group improved the most? The HIT-4 minutes group was a clear winner, both for increases in vo2 max, and for running economy. The high-heavy continuous group ranked second for improvement in vo2 max. The control and moderate-continuous training produced the worst results for vo2 max.

In an email, senior author Juan M. Murias said these results shouldn’t necessarily be applied to serious runners training more than 3 times a week. “We would rarely compartmentalize training in the way we do it here. However, it served the purpose of showing approaches to maximize successful cardiovascular adaptations for short-term training programs.” More at Medicine & Science in Sports & Exercise.

5 Workouts That Can Boost Your VO2 Max

A modest number of top Runner’s World stories are available for free at MSN if you don’t have a Runner’s World online subscription. Here’s a good one, given the results of the above study. 

Using mainly an interview with top coach and former Olympic runner, Juli Benson, the RW article explains “all about vo2 max,” and then presents 5 workouts you can use to boost your vo2 max. One is an interval workout built around 1000-meter repeats. These are likely to take you 4 to 5 minutes each, depending on your fitness.

In other words, you’ll be doing HIT-4 minute training similar to the “winning” group in the above research trial. Other studies have also found that hard 4-minute interval sessions are among the best ways to boost vo2 max. More at MSN.

No More Bonking: Plan Your Fuels For Maximal Endurance

Experienced runners and endurance athletes know they need to hydrate sufficiently and consume high-carb drinks and/or gels during long races like the marathon and beyond. However, it seems that knowing and doing are not the same thing. Not by a long shot. 

At least that’s what Spanish researchers concluded after questioning triathletes and mountain runners about their drinking and fueling during events that lasted from 6 to 8 hours. Competitors were asked about their intake of fluids, carbs, sodium, and caffeine.

Results (on average, per hour): 421 ml, 43.7 grams, 267 mg, and 15.5 mg. These amounts were generally lower than recommendations made by the International Olympic Committee and other endurance experts. Such recommendations vary by the individual athlete’s genetics, body weight, speed, and the weather conditions.

The authors were most concerned by the low carb intakes, since newer recommendation papers have been proposing 60 to 80 grams/hour, and sometimes even more. “Our data suggest the need to instruct endurance athletes to plan competitions at a dietary–nutritional level so they can implement appropriate nutritional strategies.” 

In other words, if you have a plan, you might hit the recommended targets for mid race fueling. Without a plan, you probably won’t.

However, these recommendations include the large and important BUT statement. This is necessary because “it was observed that the participants presented gastrointestinal discomfort in 61.9% of the cases.” So practice extensively in your training, and proceed with caution in events. More at Nutrients with free full text.

Bizarre Blood Issue Forces Ultra Star To Do OPPOSITE Of Blood Doping

I knew that men could suffer from too much iron (hemochromatosis). But before a recent Instagram post from ultra running world record holder Camille Herron, I didn’t realize that women could suffer from the same condition. This usually happens for hereditary reasons, and after menopause, when the women are no longer losing iron through their menstrual periods.

It’s a rare condition. Men suffer from hemochromatosis at a rate of less than 0.5% of the total male population, and women far less frequently than that.

Herron’s situation, which she only learned about in the last several years, is noteworthy for a reason. In a week or so, she’s going to take part in a unique ultra race organized by Lululemon. While full details aren’t available yet, the race, titled “Further”, will begin on International Women’s Day, March 8.

It’s designed to promote women’s endurance abilities in a 6-day race for females only. A key goal: For one of the women to set a new world record. (In that regard, it reminds me of Eliud Kipchoge’s two exhibition efforts to break 2 hours in the marathon, the second of which succeeded.)

It appears that the current record, 549 miles, was set in 1990. That’s according to Wikipedia.

A year ago, Herron covered 270.5 miles in 48 hours to set the women’s world record for that event. I would guess she’s hoping for 600+ miles in 6 days in the Lululemon event. Because, you know, it’s a nice round number.

Due to her condition, Herron now has to get regular blood-draws every couple of months, especially before a major competition like the one coming her way. More at Instagram/Camille Herron. 

Does Running With A Hangover Reduce Your Symptoms?

This is a new running-related question, so intriguing to consider. When writer Martin Fritz Huber asked a recognized sports medicine expert and a former record holder in the Beer Mile if there might be benefits to running off a hangover, both agreed that the practice made sense.

Their general logic: Vigorous exercise could help you burn off and sweat out alcohol toxins.

However, an actual expert in the subject dismissed this line of thinking. “You can’t speed up the removal of alcohol by sweating. That’s a huge misconception,” he said. He noted that most hangover symptoms are probably caused by dehydration, so drinking fluids the morning after is probably a smart approach.

But then, go ahead with your run plans. “There’s a positive chemical effect on the brain through exercise, whereas alcohol has a depressant effect,” the expert continued. “Exercise may well have a positive effect that may help overcome the negative effects of drinking.” More at Run Outside Online.

And The Last Shall Be First

Serious coverage of running has nearly disappeared from former media mainstays like the New York Times, Washington Post, L.A. Times, etc. That’s arguably a good thing for many internet running companies with their quick posts and podcasts, but it’s bad for those who used to enjoy long, balanced, journalistic stories about top runners, events, and controversies in the sport. 

Then along came an amazing story at Defector. It's a site I don’t even know, because I don’t closely follow other sports. But I heard about this story because so many runners were discussing it. Also, it’s long, it’s journalistic, it interviews dozens of almost-well known runners, and it’s about one of our most cherished events--the Olympic Marathon Trials. 

Indeed, it’s about runners who finished “Dead F___ing Last” in an Olympic Marathon Trials. Which is a fantastic angle for an emotional tale, because no one gets into the Trials unless they’re in the upper one-tenth of 1 percent of the running population. And yet someone in the super-elite pack has to finish DFL in every Trials competition every four years. This is their story.

It’s tethered by two concurrent themes. First, the Trials “is a quadrennial massacre,” to use author Dennis Young’s cut-to-the-core-phrase. A big percent of the field drops out every time. Yet deep in the fields over the last 4 decades have been a handful of individuals who “all found the idea of quitting abhorrent. They all chose to DFL.”

Thank you Dennis Young for taking the time to dig into this one. You hit it out of the park. More at Defector. 

SHORT STUFF You Don’t Want To Miss

>>> The gift that keeps on giving: High teen fitness linked to low heart problems 40 years later

>>> Beat the heat: Taurine and caffeine both work well in high heat/humidity, with a slight edge to taurine

>>> Netflix twins, vegan vs omnivore: Dr. Peter Attia says the popular Netflix documentary “failed Science 101”

GREAT QUOTES Make Great Training Partners

“A failure is not always a mistake. It may simply be the best one can do under the circumstances. The real mistake is to stop trying.”

--B.F. Skinner, American psychologist.

March 7, 2024

“Train Your Brain” A New (And Better) Way

Here’s a delicious, memorable, and highly useful quote from coach-endurance physiologist Alan Couzens. I’d say it’s even worth printing out and sticking on your refrigerator.

It goes like this: “Your brain and your soft tissue work on very different timeframes.” You could also rephrase it as: “Listen to your body … below the neck, not above.” 

Of course, there are times when the brain is a good monitor. This is especially true when it registers a high Relative Perceived Exertion for runs and other tasks that should be easy for you to perform. At these times, you need to back off.

However, many of us pay too much attention when we hear a little voice saying: “You’re not tough enough to be good.” Or, maybe: “Only the gutty survive.” Or: “When the going gets tough, the tough get going.”

This is the voice of false narratives that we’ve somehow picked up from our parents, siblings, friends, teachers, and larger social environment. We all harbor a few such narratives. But we’d be happier, healthier (and maybe faster) without them.

Couzens wants us to ignore false narratives that tell us to run more and harder despite sore muscles and achy joints. It’s an excellent message. You’ll fare much better by running less and slower. At least until your lower body tissues are fully recovered. More at Twitter/X Alan Couzens. 

New Report (From Harvard) On Plant-Based Diets And Bone Health

A fair number of runners follow a largely plant-based diet, perhaps because they’ve read studies showing this a healthy alternative to meat-heavy diets. Or perhaps because they consider it a more environmentally-friendly way to eat. 

However, other runners shy away because they fear bone-stress injuries if they go on a plant-based diet. Indeed, some prior studies have shown lower bone density and more hip fractures among those who eat mostly plants. 

Now a big new report from top Harvard researchers offers reassurance to plant-based runners. It involved more than 70,000 post menopausal women from 1984 through 2014. This is a particularly susceptible group.

Result: “Long-term adherence to a plant-based diet was not associated with the risk of hip fracture.”

Also, perhaps unexpectedly, there was little difference between those who followed a relatively healthy plant diet vs a less healthy one. The healthy approach contained more “whole grains, fruits, vegetables, nuts, legumes, vegetable oils, and tea or coffee.” The unhealthy one had “fruit juices, sweetened beverages, refined grains, potatoes, and sweets or desserts.”

However, the healthy vs unhealthy diets did produce significantly different results when the researchers looked at just the most recent 2 years. In that case, the Healthy Plant diet decreased hip fractures by 21% and the Unhealthy Plant Diet increased fractures by 28%.

Interpretation: A plant based diet--this was not a strict vegan diet but included some eggs and dairy foods--is sufficient to maintain strong bone health. To play it safe, you’d be smart to focus on the healthiest aspects of plant-based eating rather than the junkier, more processed approaches. More at J of the American Medical Association with free full text.

Exercise And Mental Health--The Now And Future Frontier

I’ve been following running and exercise studies in the scientific literature for 50 years. And here’s the biggest change that has occurred: A half century ago, the papers were all about physical outcomes, especially improvements in heart health and optimal performance.

Now, the biggest, most significant papers deal with exercise and mental health. No one saw that coming in 1970, but what a huge and important development. In this era of high-stress, high-depression, and high-suicide rates, mental health has achieved parity with physical health as a global concern.

The British Medical Journal just published possibly the best-yet review of exercise and depression. It’s a meta analysis and systematic review of only RCTs that investigated exercise and depression. 

Conclusion: “Exercise is an effective treatment for depression, with walking or jogging, yoga, and strength training more effective than other exercises.” Also, exercise effects “were comparable to psychotherapy and pharmacotherapy. Finally, “Exercise worked better when more intense.”

I frequently point out that even slow running and walk-running generally reach the level of vigorous exercise, as defined by physiologists. Walking counts as moderate exercise. That’s why the federal activity recommendations can be met by just 75 minutes/week of running vs 150 minutes of walking.

The new report pulled together results from 218 unique studies that followed 14,170 subjects. Impressive!

More at British Medical J with free full text. Also, here’s an excellent summary article at Physiologically Speaking.

On a related topic, here’s a systematic review of suicide among elite athletes. Conclusion: “Elite athletes generally demonstrate reduced risk of suicidal ideation, suicide attempt, and suicide completion compared to the general population.” 

Of course, this is an outcome based on “averages.” In real life, every athlete and every situation is different, and parents, coaches, and friends should always stay alert to mood changes of athletes they’re close to. More at Sports Medicine with free full text. And see below in this newsletter for an informative graphic.

A Surprising Way To Reduce Tripping And Falling On The Run

You’ve gotta love a research paper that asks and answers an important running question that has almost never been tested before. Especially if the paper begins with a couple of catchy sentences. 

Like these two: “To read this article, you have to constantly direct your gaze at the words on the page. If you go for a run instead, your gaze will be less constrained, so many factors could influence where you look.”

No argument there. You can’t read a magazine or a digital screen while looking up at a rainbow. On the other hand, you can look at a rainbow while running. In the Olympics, we often see top runners glancing up at a Jumbtron to see how their race is going.

So why is looking down vs looking up a good research question for runners? Because the roads and trails are covered in cracks, bumps, potholes, stones, roots, and much more. And if you’re looking up, you’re more likely to trip and fall over one of these obstacles.

Which brings us to the research question in the current investigation: Do you pay more attention to the ground in front of you when A) running alone or when B) running with a training partner?

I felt confident about the outcome. I guessed A. I was wrong. 

Here’s what actually happened. A Dutch research team asked 12 subjects to run on a path two times: once alone, once with a running partner alongside. Subjects were fitted with an eye tracking instrument that measured where they were looking. 

Result: The runners were more likely to look directly ahead (and downward toward the path’s surface) when running with a partner than when running alone. The researchers believe this happened because there is more chance of an accident when two people share a path. So each individual must pay more attention to where they are going.

Conclusion: “People appear to judge there to be more need to look where their feet will be placed when running alongside someone else.” Chalk up another good reason to run with a training partner. Also, if you do fall, a training buddy can pull you back to your feet. More at Perception with free full text.

What Serious Science Says About Ice Baths

In this article, the Skeptical Inquirer Nick Tiller, PhD, takes a hard look at the exercise benefits of ice bathing. He concludes that Wim Hof and the Tik Tok crowd are promoting an activity supported by their subjective belief in the practice. Not by good evidence.

To bolster his arguments, Tiller reviews both the physiology of muscle-fiber growth through training, and the physiology of muscle recovery. He also links to 2 recent meta-analyses.

Some muscle soreness is inevitable if you exercise, especially when you’re just starting out. “Just as a rubber band becomes frayed if you continually stretch it under load, your muscles sustain minuscule tears if they’re stretched too far or exert too much force.” 

Next, the muscles adapt by “laying down new structural proteins, like a construction crew assembling steel beams to support the infrastructure of a building.”

        

That sounds good, normal, natural, and a positive response. However, “Ice bathing fundamentally inhibits this process.” That’s why it might interfere with the very training effect you’re hoping to build through your workouts. Ice baths also blunted “the activation of key proteins and satellite cells in muscle.”

Nonetheless, in television coverage of the recent World Indoor Championships, we saw photos of world-record sprinter Femke Bol soaking her legs in an ice bath between her races. This acute practice has been supported for reduction of pain and swelling in the short term when you have to go to the start line again very soon. However, it’s not the best long-term practice.

At any rate, the many supporters of ice baths had plenty to say to Tiller on his Twitter/X feed. Especially those espousing “mental and emotional benefits.” Hey, if you think it feels good, go for it. But don’t expect to get stronger or faster. More at Skeptical Inquirer.

Good News For Runners With Long Ground-Contact Times

Running economy is considered a pivotal measure of distance-running success, and is often related to stride biomechanics. RE is important because you can continue to improve it over many years even after you have reached a ceiling for vo2 max. Some but not all studies have found that a shorter foot-contact time is linked to improved running economy. 

However, a new paper from Japan produced the opposite outcome for “17 highly trained runners.” They were capable of running times in the low 14’s for 5000 meters, and the low 29’s for 10,000 meters. Ten were midfoot strikers, and 7 rearfooters.

This lab research looked for links between running economy, contact times, footstrike landings, and upper-leg musculature. 

Result: Longer ground contact time improved running performance and running economy. Footstrike pattern had no impact on these findings. 

Lastly, and uniquely in my reading of running-economy papers, the researchers found an association between smaller upper-leg muscles and higher running economy. (Put the other way: Larger quad and hamstring muscles decreased running economy.)

This doesn’t mean that strong quads and hamstring are unimportant in distance running. It just means that you don’t want to bulk up with extra muscle above the knees.

Conclusion: “Large cross sectional area of knee extensor muscles results in short ground contact time and worse running economy.” Conversely, small thigh muscles are linked to longer ground contact time and better running economy. More at J of Strength & Conditioning Research.

Do Women Gain More From Their Workouts Than Men?

Several weeks ago I saw headlines declaring “Women get more benefit from exercise than men.” I looked briefly at the study in question, but it didn’t make the final cut here at RLRH. 

I don’t actually remember why. It was probably a simple matter of more compelling stories about more serious training and nutrition.

Last week I came across several reports criticizing the original study, published by the Journal of the American College of Cardiology (with free full text.) These were more interesting than the initial report because they raised compelling arguments.

You might have seen one of the original reports also. Here’s why you shouldn’t believe what you read then.

The main problem: The study was based on self-reported physical activity--a notoriously bad way to measure exercise. Sometimes it’s all you’ve got, and there’s no reason not to do studies based on self-reported exercise. But you have to be careful about your conclusions.

Especially if you’re trying to suss out differences between the sexes. Why? Because men are known to lie more about exercise than women. One prior study based on actual objective exercise measures showed that men reported 47 percent more exercise than women when in fact they were doing the same amount as the women.

If men aren’t doing the exercise they claim, then they obviously aren’t reaping equivalent health benefits. So, despite the study in JACC, it’s unlikely that women benefit more from exercise than men. They’re simply being more honest in their self-reports of daily activity. More at ConscienHealth. 

How To Tell That A Teen Runner Might Be Facing Menstrual Dysfunction

It’s sometimes hard to tell when a young female runner is under-fueling (Low Energy Availability), and brief periods of LEA are often well tolerated. On the other hand, missed menstrual periods are a clear sign of female physiological dysfunction. Missed periods must be taken seriously, as they can lead to short-term and life-long health issues, particularly bone problems.

For that reason, a group of Italian researchers conducted a study with runners “of fertile age” to see how many had regular menstruation (about 60%) and how many had irregular periods. The 40 percent with menstrual irregularities represent about double the prevalence in the full population. The researchers asked their subjects about their training, diet, and other factors to see what links they might uncover. 

The average weekly mileage was 46 km--about 29 miles per week. Caloric intake was below the suggested amount (2000 calories/day) in 51% of subjects, but did not distinguish between atypical menstruation and normal menstruation. Nor did BMI. Also, the injury rate was the same in those below and above 2000 calories/day.

Key result: A training distance over 40 miles per week was associated with menstrual dysfunction, whereas other measured factors were not. 

Conclusion: “The variable of kilometers run per week was associated with menstrual irregularities with statistical significance.” Also women with menstrual irregularities tended to train more than 5 days a week, and to include additional non-running workouts in their training program. 

Application: In this report, total running mileage (along with total runs/week, and number of extra non-running workouts) provided the most powerful link to menstrual problems. Adolescent females should be careful about high-mileage training. More at International J of Sports Medicine with free full text.

The Latest Attempt To Explain East African Marathon Dominance

Humans are good distance runners, relative to many other animals, because we’ve evolved efficient means of body heat dispersal. Most of this comes from our low body hair covering and high sweat rate. 

These factors have been recognized for a long time. They’ve received more coverage since Dennis Bramble and Daniel Lieberman published their paper, “Endurance running and the evolution of Homo,” in Nature in 2004.

I’m not sure, however, if anyone has extended this thesis to explain the marathon excellence of runners from East Africa. Are they the best Homo runners because they have the best heat-dispersing bodies?

That’s the basic claim of a modest paper in a little-known journal by several researchers from Kyrgyzstan. No, I’m not messin’ with you. This team is interested in “one poorly studied physical peculiarity of the human body, namely its heat-conducting ability.”

The authors claim to be experts in “the variability of chromosomal Q-heterochromatin regions (Q-HRs) in human populations.” They have observed, for example, that peoples living in mountainous regions have a low Q-HR, and people from high, arid regions have a high Q-HR. 

Q-HR is basically a measure of “body heat conductivity.” It is notable, the new paper states, that “a sportsman with high heat conductivity cannot make much progress in mountaineering and water sports because their body cools rapidly. However, this sportsman can be more successful in sports, which require effective heat-loss.”

We all know that the marathon is, in part, a fight against rising body heat. It’s also impossible to miss the dominance of East African runners in the marathon. Specialists in exercise genetics have spent the last 30 years looking for an explanation. They’ve mostly failed. 

Now we’ve got a new candidate: high body heat conductivity as measured by Q-HR. Maybe East Africans have a higher Q-HR than other groups.

The authors conclude: “Perhaps our ancestors acquired their unique ability--endurance running--when they were struggling for existence on the African savannahs.” More at Medical & Clinical Research with free full text.

A Cool Graphic From That Exercise & Depression Review

Here’s one of several interesting graphics from the above-mentioned article on exercise vs depression. This line shows that higher intensity exercise is more effective at lowering depression than less intense exercise. More at British Medical J with free full text.

SHORT STUFF You Don’t Want To Miss

>>> What’s more important, diet or exercise? Here’s a rare, free Peter Attia podcast transcript on nutrition and longevity. Given the many uncertainties about diet, Attia concludes: “It’s better to put your energy into exercise.”

>>> Bend your toes (downward): This simple toe exercise can strengthen the foot’s intrinsic muscles, and help prevent injuries.

>>> Train your gut: Can a probiotic supplement lower your risk of GI distress on the run?

GREAT QUOTES Make Great Training Partners

“Running allows me to set my mind free. Nothing seems impossible, nothing unattainable.”

--Kara Goucher, Olympian, book author, podcast host, TV commentator

That’s all for now. Thanks for reading. See you again next week. Amby

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