August 31, 2023

A new dimension in marathon training could be the key to success

Exercise physiologists have been picking apart the marathon for a long time, and have almost unanimously agreed that there are three keys to top performance. They are: 1) high vo2 max; 2) high running economy; and 3) high fractional use of vo2 max (similar to high lactate threshold).


Now British endurance expert Andy Jones, who has worked with everyone from Paula Radcliffe to Eliud Kipchoge, is formally proposing a “fourth dimension” to marathon performance. He’s calling it “resilience.” Others have used terms like “durability” or “muscle fatigue resistance.”


They’re all talking about the same thing, and it’s not the way your body performs when you are fresh and primed for a hard run on a laboratory treadmill. Instead, resilience is the way your body performs after 20 miles of bone/muscle/cardio crunching road race effort. It’s the factor that often determines who wins a marathon, and who doesn’t.


We don’t know much about resilience because little laboratory data has been gathered. For one thing, you’d have to pay subjects a lot to undergo the torturous testing. Also, it would take a lot of laboratory time, effort, and equipment (ie, $$$ again).


Some of the barriers are being overcome by lightweight digital devices and ingestible micro sensors that can monitor internal conditions. Still, it’s a long road ahead. 


Anyway, that’s the backdrop to Jones’s paper, “The fourth dimension: physiological resilience as an independent determinant of endurance exercise performance.” The paper explores “key variables that are not static but subject to deterioration during endurance performance.”


As marathon runners, we mainly want to know how we can improve our resilience. Jones has several ideas. You gotta wear super shoes, of course. We see that in the way top marathon runners are now running negative split races. At London last April, Kelvin Kiptum ran 61:40 for the first 13.1 miles, and 59:45 for the second half to finish in 2:01:25. In addition, the more carbs you can consume on the road, the longer you’re likely to remain fueled and efficient.


Jones also believes that “age and/or consistent, long-term, perhaps high volume, training may play an important role.” Studies of runners like Paula Radcliffe and Eliud Kipchoge have shown that they can improve steadily over a decade or more if they continue their high-level training.


Other possible resilience enhancers: “regular training in a fasted and/or glycogen-depleted state (through, for example, twice-daily training or overnight carbohydrate restriction).” And: “endurance training sessions where the speed is held constant at close to race effort or progressively increases

with time (as practiced by, for example, Eliud Kipchoge).”


This is just a beginning list. More is sure to come as “resilience” receives more investigation and research. More at The J of Physiology with free full text.


How to pick the best overall diet for optimal athletic performance 

A team of Stanford experts with a strong background in endurance sports have produced a simple, complete analysis of how various popular diets affect athletic performance. We’re talking about virtually all the diets you hear discussed by your friends, on Internet websites, and in the media: Mediterranean diet, low-carb and Keto diets, vegan and vegetarian diets, and intermittent fasting. 


The report is free and simple to follow from the link below, but here’s the briefest of summaries. The Mediterranean diet “has some of the most robust research” on performance. Ketogenic diets are more stringent than low-carb diets in terms of limiting carb intake, “although many conflate the two.” Next comes a double-negative: “Both have not been shown to be detrimental” to performance. I think I’d argue against that--at least as applied to world class endurance efforts that last several hours or less. That’s where carbs really shine.


Vegans and vegetarians face “increased risks” of falling short on vitamins B12 and D, as well as zinc, iron, and calcium (and possibly the amino acid leucine.) Intermittent fasting, “although proven to promote weight loss, has been shown to decrease” endurance performance. More at Nutrients with free full text.


On a separate question relating to carbohydrates and performance, a research team wondered if carbohydrates improve endurance performance through an effect on the brain’s “executive function.” It’s a good question, given the current attention on how the central nervous system affects exercise. Maybe carbs work through the brain, as well as through glycogen and blood glucose?


But no. This systematic review and meta analysis of 10 randomized trials found that “Carbohydrate intake before or during exercise was not significantly effective in reducing the decline in EF after exercise.” More at Frontiers in Psychology with free full text.


More evidence that sodium bicarbonate can improve endurance

The use of sodium bicarbonate, otherwise known as cheap, omnipresent baking soda, is popping up all over. The basic kitchen product has long been known to improve performance in high power, short duration events like sprints or middle distance races. Now it seems to be creeping into longer races.


But first things first. There’s always a big IF related to baking soda use. It doesn’t work unless you can tolerate it without significant gastrointestinal problems. That’s one of the main issues that researchers have to investigate when designing baking-soda experiments.


In this new study, baking soda made a substantial difference in 10-mile time trial performance of 10 “trained cyclists”--the kind of high-fit subjects who are tough to budge from their best, already top-level performances.


The cyclists repeated three separate 10-mile time trials. In one trial, they received a placebo. In the other two, they received .3 grams of sodium bicarbonate per kilogram of body weight in either a gelatine or in a capsule. 


Result: “Performance time was significantly improved by SB ingestion compared to the placebo.”

Importantly, there was also a difference in GI issues. They were significantly lessened by the capsule vs the gelatine. The capsule also resulted in slightly better performance than the gelatine.


Conclusion: “This study demonstrates that increased buffering capacity following acute pre-exercise SB ingestion, can improve endurance cycling time trial performances.”


The researchers didn’t speculate about longer races. A fit cyclist can complete 10 miles in under 30 minutes, so we don’t know how sodium bicarbonate would affect a high-effort 3-hour test. Also, in this trial, the cyclists were not given a pre-ride meal, which would be common in most real-life racing efforts. More at  Medicine & Science in Sports & Exercise.


Should you consider carrying extra weights while running?

I still own a pair of ankle weights that I bought in my adolescent running years. I thought the weights would make my run training more difficult, and that the increased training effort would stimulate improved race-day efforts. At the time, I pretty much believed in the “more is better” approach to running.


My brief experiment didn’t end well. I can’t say it’s because the weights failed me; I stopped using them because it was no damn fun. They made my running clunky and uncomfortable, so I relegated them to the basement cobwebs.


However, others are still testing the idea. When running biomechanists added 1 kilogram (2.2 pounds) to each foot of runner-subjects, they observed “only moderate kinematic” changes in movement patterns. Things were quite different at the joints though, where maximum joint forces increased as much as 40% for knee extension and 50% for joint power of hip generation, both in the late swing phase of running.


Conclusion: “These changes have implications for people who run with added mass on their legs for sport/strength.” I’d say the implications include: Be very, very careful not to overdo it. In fact, I’ll never again try my ankle weights for actual running. Maybe for the bike, elliptical, or StairMaster. But not on the road. More at Applied Ergonomics.


A little extra weight is easier to carry on the upper body than on the lower legs, and ultra runners often find it helpful. After all, they might have to go it solo for several hours between refreshment checkpoints. Meaning: They have to carry their own fluids and fuels.


To give this crowd some useful data, researchers recently tested runners on a laboratory treadmill while carrying nothing, 5 kg (11 pounds) or 10 kg (22 lbs) in a weighted vest.


They found that the 22-lb pack had an overall negative effect, as it increased ground contact time. On the other hand, the 5-lb pack seemed to hit a sweet sport. It didn’t alter runners' basic biomechanics, yet managed to increase leg stiffness--generally thought to be a good finding linked to better running economy. 


Conclusion: Running with “an additional load equivalent to +5% body weight” yields “improved running performance.” But more isn’t better. In fact, adding another 5% of body weight turned things around and produced a negative result. More at Sensors.


6 fixes for common training errors

Tom Goom, the British-based “running physio,” produces scads of great running content. Much of it deals with injuries, but he also understands every runner’s interest in getting faster. You can find Goom’s content on his YouTube channel and also from his website


The videos are stiff, but info packed, evidence based, and runner specific, which makes them rank high among valuable web resources for runners. Most are also manageably short at 5 to 15 minutes. 


In this video he describes 6 training errors he observes frequently among his patients. Importantly, he also offers a “fix” for each.


The errors: 1) Training too hard or too often; 2) Bad exercise technique; 3) Poor exercise selection; 4) Not progressing with the plan; 5) Ignoring weaknesses; and 6) Lack of periodization.


The fixes: 1) Manage intensity better, take rest days, be careful to avoid overtraining; 2) Reduce weights or reps while working on better form; 3) Choose multi-joint exercises over isolation exercises; 4) Once you’ve mastered technique, increase weights or reps; 5) Analyze your weaknesses, and begin specific exercises to improve; 6) Plan mesocycles that take you to a planned peak by increasing weights/reps/intensity. More at YouTube..


A simple (proven) way to find your max fat-burning zone

Most of the time we runners don’t worry much about max fat burn. You don’t win races that way, or hit your goals. But there are still situations where max fat burning might become interesting. Maybe if you’d like to lose some body fat. Or if you want to try one of those training regimens aimed at teaching your body to spare glycogen during loooong efforts.


If so, the big question becomes: Where the heck is my max fat burning zone? That’s the answer we get from this systematic review and meta regression paper that delved into 64 previously published reports on max-fat-burning.


Result: Assuming that you have a body-fat percentage under 35%, your max fat burn will occur when you are exercising in the range from 57 to 64% of your max heart rate. Sixty percent seems like a nice round number that should be close. When you run or exercise at a higher heart rate, your body begins to use carbohydrates as the preferred fuel source. 


Biological sex did not appear to influence the results, and heart rate was more effective at determining max fat burn than percent of vo2 max. That’s good, because heart rate is much easier for individuals to monitor. More at Sports Medicine.


Why a 10-day training “week” could be better than 7 days

The 7-day training week is probably followed by 99 percent of runners. It accommodates a typical 5-day work week--though, let’s face it, the work week is getting less typical all the time, which should allow for some interesting variations on 7-day training weeks--and often includes long runs or races on weekends. 


But the predominance of the 7-day week doesn’t mean it’s the best way to go. There are many good arguments for longer “microcycles”--for example, the 9 or 10 day microcycle.


What are the benefits of the longer time frame? That’s an easy one. More time to do essential workouts like long runs, tempo runs, and intervals, with more recovery between each of the Tri-Peaks of training. 


Elite and high-fit athletes often do all three of the above in a 7-day period. And they succeed because, after all, they are the creme de la creme. Most of us are not. We need more recovery. A 9 or 10 day cycle allows us to get what we need.


Sure, you’ll end up doing just 3 long runs or tempo runs, etc, in a month vs 4 of these key workouts. But do you really think that’s enough to limit your fitness? What about the benefits of extra recovery time between hard days? You’ve gotta put a high value on that.


Here, the Reddit runners debate all the above, and share various articles supporting or illustrating their personal favorite approaches. One respondent who has spent a lot of time thinking about training cycles makes this important point for marathon runners. “It's probably better for most people to only do a big long run every 10-14 days, and then fill in with a higher frequency of medium long runs (~90min).” More at Reddit.


“Active recovery” improves performance in your next workout

You did your “hard day” maybe with some speedy running, or maybe by covering extra distance. Good for you. Now what?


It’s one of those eternal training questions. What do you do the day after a serious workout? You could follow up with an easy run on the assumption that “active recovery” is the way to go. Or you could take a total rest day, figuring that complete, passive recovery--basically doing nothing--will give you the most adaptation.


Here an Italian team (with a big interest in cycling) put the question to an experimental test. This is the procedure they used: They asked 12 “well-trained cyclists” to complete a laboratory procedure that included two all-out efforts called a “Wingate anaerobic test.” In this test, cyclists pedal as hard and fast as possible for as long as possible, often about 30 seconds. 


Between the two WATs, the cyclists either took 30 minutes of passive recovery, doing nothing. Or they pedaled easily for 30 minutes. The experimental question: Which recovery produced the best outcome on the second WAT?


Result: Score one for an active recovery. During active recovery, the cyclists showed greater “clearance” of blood lactate, and were subsequently able to produce more power in the second WAT. Conclusion: “This suggests that AR of submaximal intensity can induce a post-activation performance enhancement when used during the recovery phase.”


Important note: There are major differences between cycling (a zero ground-impact activity) and running (with its substantial ground-contact forces.) This could mean that running as an active recovery may not be beneficial, as it would continue to stress the leg muscles. That’s why many top runners favor moderate cycling as an active exercise between running workouts. Cycling can boost recovery without injuring running-essential muscle fibers. More at Heliyon.


SHORT STUFF you don’t want to miss

>>> 10 steps to a faster marathon

>>> How you can “engineer happiness” on the run by understanding the interplay of reality and expectation

>>> 9 reasons why runners should improve their ankle strength


GREAT QUOTES make great training partners

“You don't have to be fast. But you'd better be fearless.”

--Christopher McDougall, author, Born to Run


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