Back in June, I watched online as Faith Kipyegon unsuccessfully tried becoming the worldâs first sub-4 miler woman. The event was one of those multi-million-dollar circus shows put on by Nike to test human physical limitations. It was elaborate enough that, just like Eliud Kipchogeâs Sub-2 in 2019, it would not have counted as a world record should she succeed.
Athletics and the principle of diminishing returns (Image by ChatGPT)
Kipchoge needed to improve his marathon time by 100 seconds, and he did, finishing 19 seconds ahead of his previous record. Kipyegon needed to shave about 8 seconds (7.65) to achieve her goal, but she ended up about 6.5 seconds short. Even with the circus, space technology, support, and male pacing, she couldnât do it.
The failed attempt got me thinking about a basic concept in economics that easily applies to running: the principle of diminishing returns. In economics, this means that ff you improve one variable while keeping all the others constant, the incremental output gained from each extra unit will eventually fall. In other words, building a skyscraper in one day wonât be solved with more workers.
The same principle applies in athletics. Dr. George Sheehan, one of the greatest running writers, put it this way: âThe first mile is the most helpful one as far as conditioning goes. Each succeeding one gives less and less benefit than the one before. Runners who work more and more are working for less and less. [âŠ] It doesnât take much to get 90% fitness, only a few miles a day. But it takes progressively more and more training as you get closer to your ultimate potential. At the highest levels, you are putting in a huge investment for a very small return. It is the small gains what makes the difference between winning and losing.â
Think about it, itâs obvious. If not, it would be a matter of time and more miles before we all became elite athletes and broke world records. We all have a limit, and while reaching it is feasible, it requires a tremendous amount of work.
I recently heard Coach Steve Magness share a story where Shalane Flanagan told him something along the lines of, âThe difference between being in 2:30 marathon shape and 2:20 is astronomical.â For you and me, average, mid-to-back-of-the-pack marathoners, a 10-minute improvement may be a diligent training cycle away. For elites in a Marathon Major, this same result guarantees them peeing in a cup to verify cheating.
Nice background, Coach! But how does this apply to me, the average weekend warrior?
It is about training smarter, not harder (Image by ChatGPT)
I am glad you asked! The point of this introduction is for the reader to understand that the curve of progress in running flattens as we improve. It is a reality we canât solve with harder training. Progress is not a linear proposition.
And, while achieving the last 10% requires an astronomical effort, it is feasible. It is about figuring out what works for you. Just because Jacob Ingebrigtsen uses the Norwegian double threshold method doesnât mean it is the solution youâve been looking for. He is in such shape that this is the only type of training that will extract the extra hundredths of a second needed to break a world record. This training may land you, my dear average-runner reader, on the injury list.
Working around the principle of diminishing returns to reach your apex requires smarter training. Not just harder. As gains slow, finding that sweet spot between effort and recovery is the magic sauce. It may mean varying your workouts, adjusting intensity levels, or prioritizing recovery and nutrition more seriously. As we improve, we must tune into our bodyâs signals, such as fatigue, soreness, or lack of motivation. These can guide adjustments before you hit a training (or overtraining) wall. If in doubt, a training plan tailored exclusively for you may help you progress without burning out.
In conclusion, In athletics, more is not necessarily better. Most of what elite runners do to squeeze that last sliver of greatness out of their performance does not apply to you. We are all limitless, sure, but not in all areas of our human performance, athletics being one of them. Letâs work hard to reach our goals, but not at the expense of burning out.
What are your thoughts on this principle? I will read and answer your comments.
As long-distance runners, we focus on the long-distance run. Obvious. For marathoners, that 20-miler has been a staple our training for decades. The psychological advantage of having achieved that distance starting with a 2 instead of a 1, when you are about to run 26.2, cannot be overstated.
The benefit of that 20-mile run lies in the time it will take you to complete it (Image by ChatGPT)
Yet, there is no magic to be gained at 20 miles. If you train in kilometers, 20 miles is 32.18 Km, far from a round or memorable number. The âmagic markerâ for those who train in kilometers is 30, for the same psychological reason. This is equivalent to 18.64 miles. Nothing special to that figure either.
But, is there a physiological benefit from running a 20-miler or 30 kilometers, or two or three of them before your marathon? Does it apply to all marathoners? What does science say about this? How does all this apply to you and your training for your next marathon?
Letâs get into it.
While the confidence boost of having a 20 or 22 mile run under your soles is undeniable, its benefits are proven to diminish the longer you are on your feet. The elite Kenyans can cover the distance between less than two hours. The 3-hour runner can do it in 2:30-ish at an easier pace. But the 4-hour marathoner may take 3:45 at an easy pace. You can see the progression.
According to scientific studies: âafter running 3 hours the aerobic benefits (capillary building, mitochondrial development) arenât markedly better than when you run two hours.â This means that a 3-hour run will provide as much aerobic benefit as a 2-hour run. So you will accumulate additional fatigue and need a longer recovery before resuming your normal training.
Iâve read about coaches that do not prescribe 20-mile runs for anyone looking to run over 3:45 in the marathon. Others say 3:30 or even less. Remember that coaching is the intersection between art and science. An art based on science, not a science per se, so trial and error are part of the deal.
In my professional experience, runners that will run their marathons on the slower side than 3:30ish, will benefit from back-to-back runs that will allow accumulated fatigue to do its thing without breaking down the body too much. A long run today followed by a âlongishâ run tomorrow, where you accumulate from 18-22 miles in a weekend, produces better results than plowing through that mileage in one push.
You can achieve more with less time on your feel and more time to recover (Photo Pexels)
This is not to say that for certain runners, at a certain level of fitness, with a certain goals and with enough time to recover, may not benefit from a 20-miler. And I am not discounting the psychological benefit either. What I am stating is that the 20+ miler is not the key to achieve your marathon goals if you are not on the faster side.
Coach Jeff Gaudette, from Runnersâ Connect, wrote recently that one of the two primary reasons why runners get injured is âorogressing their training volume and running speeds at a pace that their body is not ready to handle. Or, as coach Jay Johnson would technically define it, âmetabolic fitness precedes structural readinessââ.
Before you ask, the other reason is structural imbalances and/or bio-mechanical issues.
Coach John Davis, a PhD in biomechanics at Indiana Universityâs School of Public Health, provides the following recommendations when it comes to the long run in a marathon training cycle.
Donât overemphasize the long run, especially when training for the marathon. Not only do aerobic benefits flat line after 2 hours of running, but as this research shows, injury risk increases significantly.
Think prehab rather than rehab. Work on strengthening known or potential weak areas in your running mechanics.
Fix flaws in your running form that become exacerbated during long runs. Improving posture, learning to generate proper hip extension, and fixing overstriding can help prevent many potential injury issues.
In conclusion:
The long run continues to be an essential element of the marathon training. Thereâs no way around it. But contrary to what has been drilled to us for so many years, the qualifying aspect of the long run is time, not necessarily mileage. It is not the longer the merrier. It is the longer you can run without hindering your recovery, the merrier.
It took me a while to understand it, but with maturity, I finally did. Training consists of two separate and different elements: Work and recovery. They are equally important, and they complement each other. Their symbiosis confirms the Aristotelian saying that the whole is more than the sum of the parts.
Recently, I heard that the second element is labeled as The Invisible Training.
It got me thinking about a classic Emil Zatopek quote where he states: âWhat you do when the stadium is full is important, but what you do when the stadium is empty is a thousand times more important.â
For us amateur weekend warriors, a standing ovation at an Olympic stadium is no more than a pleasant dream. Yet, well into the XXI Century, each one of us has the equivalent of our own Olympic stadium, and we have become addicted to that standing ovation of kudos Strava, followers on Facebook, and likes on Instagram. These may be cool for many, but they wonât get you any better.
As Zatopek (a 4-time Olympic gold medalist and multi-world record breaker) said, that is not the key to success. It is what we do outside the limelight that counts. A thousand times more.
âș It is the strength training that will help you get stronger, more resilient, have a better form, and make you injury resistant.
âș it is the physical therapy you do to take care of your bones, muscles, and soft tissues. Not just face-to-face with a professional, but as a prehab to avoid a recurring injury.
âș It is your daily nutrition that allows your body enough of the good stuff to repair itself and be appropriately fueled for your activity.
âș It is the hydration throughout the day that will allow you to sustain a hard run even in the harshest of weather conditions.
âș It is the scheduled recovery for your body to adapt to the stress we have put it through and accepting that sometimes it will require more time.
âș It is understanding that sleep is the champion of recovery tools in your arsenal and that lack of sleep is not a badge of honor.
âș It is accumulating knowledge about the sport and the function of your body, which will allow you to understand whatâs happening and why.
âș It is the evaluation of your training, especially when you have bonked or screwed up, and accepting it as an opportunity to learn and build experience.
âș It is living a balanced life, one where your job, your family, and your friends wonât be neglected, and end up resenting you and your running.
âș It is allowing yourself to have fun outside your running life. Keeping it all in perspective and always remembering why you are doing this.
These are just ten of hundreds of parameters of what is encompassed within the realm of invisible training.
In summary, everything you do while you are not running is equally essential to the running time.
Yes, it all sounds intuitive, simple, even obvious. But weâve all fallen into the trap of only accepting hard work as worthwhile training. And to many, an injury has taught us how wrong we were. My wish is that this brief writing will help avoid the injury part for you, dear reader.
Share your thoughts in the box below so other runners may benefit from your experience.
No sugar coating it: Running in the heat and humidity of the summer sucks. It does. However, if we want to remain active during these challenging summer months of running and have any chance of having a solid racing season come fall, we must continue training. And to make hot weather running enjoyable and safe, the only way is by making substantial adjustments.
I’ve shared summer running tips every year since I began blogging, but this time I decided to do something different. I have gone through my previous writings on the issue and consolidated the tips. These, plus a handful of new ones I’ve added, bring the final count of summer running tips to 39.
To be clear, nobody expects you to apply all 39 of these hot weather running tips on every run. These are just guidelines and suggestions with very short explanations to get your thoughts started. I have included links to posts where I have explored the issues in more depth. And if you’re looking for more background or science behind these summer running safety tips, a quick Google search will point you in the right direction.
So, without further ado, here they are:
1 – Listen to your body â If you feel dizzy, nauseated, or overheated, don’t hesitate to stop, cut the run short, seek shade, ask for help, or just call it a day.
2 – Recognize heat stroke symptoms â Know the difference between exhaustion and heat stroke and familiarize yourself with warning signs like confusion, rapid pulse, or clammy skin.
3 – Hydrate all day â Hydration should be a 24/7 habit that keeps you close to fully hydrated by the time you start your GPS watch.
4 –Don’t overhydrateâ Overindulging in water or sports drinks can cause hyponatremia, a condition in which diluted sodium levels may lead to seizures, coma, or worse.
5 – Use electrolytesâ Supplementing with sodium, potassium, and magnesium helps your body retain and use the fluids you’re drinking more effectively.
6 – Run early or late â Run before sunrise or after sunset to avoid the most extreme heat and protect your body from overexertion.
7 – Monitor the heat indexâ Skip your outdoor workout if it’s over 98°F with more than 70â80% humidity, as your risk of overheating skyrockets.
8 – Slow down your pace â Running in the heat is harder, so let go of your pace goals and focus on effort instead of speed.
9 – Accept higher perceived effort â A rise in core temperature, not lactate or heart rate, becomes the main fatigue limiter in hot conditions.
10 – Use effort and time, not pace â In summer, pace and heart rate can be unreliable, so go by effort and run by minutes instead of distance.
11 – Recognize the signs of dehydration â Watch for fatigue, brain fog, darker urine, dizziness, or a dry mouthâthese may all signal fluid imbalance.
12 – Prehydrate before long runs â Do not cram your hydration; it doesn’t work that way. Hydrate throughout the day and days, not just before your run.
13 – Rehydrate after running â After a sweaty session, replace fluids with water or an electrolyte drink. Not only as soon as you’re done but throughout the day.
14 – Dress light and bright â Light-colored, loose, and moisture-wicking clothing helps reflect sunlight and allow sweat to evaporate more easily.
15 – Train in the shade â Routes with trees or buildings that block direct sun can be 10â15°F cooler and far more comfortable, and safer.
16 – Freeze your gear â Put your shirt and hat in the freezer before a run to delay overheating and make the first few miles more tolerable.
17 – Take short breaks â Stop for 1â3 minutes during a hot run to drink, throw water on your head, or reset your effort perception.
18 – Use water for recovery â Jumping into a pool, cold bath, or even running through sprinklers post-run can drop your core temp and revive you.
19 â Know where the water is â If you don’t know where the reliable water sources are, run with a handheld bottle or hydration pack.
20 – Run indoors if needed â If conditions are extreme, choose a treadmill or indoor track to get your miles without the heat risk.
21 – Build heat tolerance gradually â It takes a few weeks to acclimate, so ease into hot-weather running instead of diving into hard efforts.
22 â Move workouts around when necessary â Move long or intense workouts to cooler days and use weather apps to plan smarter each week.
23 – Use a heart rate monitor â Heat elevates heart rate, so monitor it to avoid overexertion while running.
24 – Expect it to suck â The first few weeks of heat running will feel awful, but your body will adjust and it will suck less. Proceed with caution.
25 â Adjust your training plan â In very hot climates, push harder workouts like long tempos to the fall and focus on base-building instead.
26 – Exploit cooler days â When temperatures drop, use the opportunity for a strong tempo or threshold session to boost confidence.
27 – Don’t obsess over metrics â During summer training, forget about pace, Strava comparisons, or even distanceâsurvival and consistency are the priority.
28 – Take advantage of trails â Shaded trails provide natural cooling, softer surfaces, and often more enjoyable running when it’s hot out.
29 – Eat hydrating foods â Boost your fluid intake by eating fruits and veggies like watermelon, cucumber, and oranges, which are 80â90% water.
30 – Beware of diuretics â Limit high doses of caffeine or alcohol around runs, as they increase urination and risk of dehydration.
Learn how to gauge your level of exhaustion (Photo: Tima Miroshnichenko, Pexels)
31 – Set hydration reminders â Pair water intake with daily habits like brushing your teeth, meals, or use phone alerts to stay on track.
32 – Sip, don’t guzzle â Drink water steadily throughout the day and during your run to avoid bloating and improve absorption.
33 â Internalize year-round hydration strategies â Treat hydration like a year-round discipline, not just something to focus on when it’s hot.
34 – Know your sweat rate â If you’re a heavy sweater, you may need more fluids and sodium than the average runner.
35 – Pair hydration with daily habits â Combine drinking water with routines like meals, workouts, or bedtime to form easy-to-remember habits.
36 – Double instead of going long â On non-long run days, two shorter sessions may be safer than a longer push under the brutal heat. Consider it if needed.
37 – Use treadmill for quality work â Use a treadmill to maintain pace accuracy or intensity when outdoor heat makes it unsafe.
38 – Keep someone informed â Always tell a friend or loved one your planned route and expected return time, or use live tracking apps.
39 – Know the line between tough and dumb â Being smart and cautious during summer training keeps you healthy and able to run tomorrow.
Did I miss anything, or would you like to contribute to the list? Please do so in the comment box below.
As summer temperatures rise across the Northern Hemisphere, runners in warmer regions like South Florida already feel the heat. You donât have to wait for June 21st. In many places, summer conditions arrive much earlier. Now is the perfect time to revisit how heat and humidity affect running performance so you may adjust your training and remain strong, safe, and consistent in hot weather.
Running in the heat requires adjustments and patience (Image by ChatGPT)
In previous years, I have written about tips for summer running and guidelines to run in extreme heat. You can click the links in this paragraph to read those posts, which I highly recommend. This year, I am writing about a different aspect of this subject. While intuition tells us heat and humidity affect our running, this year, I want to dig a bit deeper into it.
I recently read about a study measuring the effects of those two elements on marathon performances. My goal today is not to show you how an 80Âș temperature or 70% humidity will adversely affect your marathon time. What I want to do is project what these difficult weather conditions affecting a marathon mean for you, training every day in the heat.
Letâs start with one of the studyâs most interesting takeaways: runners donât slow down simply because their core temperature gets too high. They slow down before that happens. In other words, heat doesnât just tax your body; it messes with your brain. The rate of perceived effort rises early, and that alone is enough to force a drop in pace. You feel like youâre overdoing it, even though your physiology is within range. This is not just psychological, itâs your body protecting itself. When the humidity is high, the fatigue effect compounds.
According to John Davisâ analysis of nearly 4,000 marathon performances across 754 races, the optimal temperature range for top performances is narrow: 35â55°F (2â13°C). Performance peaks around 48°F (9°C). As conditions warm beyond 65°F (18°C), things deteriorate, and they do so fast, especially when humidity becomes part of the equation. A heat index of 80°F (air temp and humidity combined) can slow your marathon pace by roughly 3%, and it only worsens.
In extreme cases, like 75°F and steamy, youâre looking at 6â8% slower marathon times. Thatâs 10â15+ minutes lost for someone aiming for 3:00, 14-19+ if you aim for 4:00, and 18-24 if you are shooting for 5:00.
But hereâs where it applies to your day-to-day running: that slowdown isnât just for race day. You need to adjust mentally and physically if youâre doing tempo runs, long runs, or any effort-based session in hot, humid conditions. Your body is under extra fatigue. Itâs not about being weak, itâs about heat load. Think of it as carrying an invisible weight that gets heavier the longer you carry it. You donât need a calculator to tell you this. If it feels harder, it is harder.
Humidity alone is not a significant issue until the temperature crosses 65°F (18°C). After that, humidity and heat multiply their effects. So, if youâre in a place like South Florida, where hot and humid is the baseline from May through September, your training isnât just slower, itâs under constant stress. Knowing and accepting it allows you to reframe your expectations, adjust your pace, and be kind to yourself when the stats on your watch donât match your effort.
Running in the heat
Davis recommends using the heat index rather than raw air temperature to judge effort. The âfeels likeâ measure is a more useful parameter. If youâre training in an 80°F heat index, expect that same 3% drop-off, even on a regular weekday run. The longer the effort, the more critical it becomes to respect this adjustment. And this doesnât just apply to marathoners. For any longer sustained effort, these principles apply.
Heat adaptation, hydration, and fitness all play a role in adjusting to the reality of the new weather. If youâve been out there, you know the stress is real, and if youâre not changing for it, youâre not training smart. Use this validated science to listen to what your bodyâs been trying to tell you. The heat isnât just uncomfortable; itâs performance-changing. If you ignore it, it can become dangerous and even life-threatening.
Share your experiences running in the heat in the box below, so other runners can benefit from them.
In a WhatsApp running group, one of our friends recently shared an article from Menâs Journal Magazine praising the benefits of training in a fasted state. The sub-title alone was promising: The Science-Backed Benefits of Running on Empty, by Spenser Mestel.
I opened it as I thought of how pseudo-science has affected even the most mundane, easy runs lately. Most come from unqualified social media influencers or studies commissioned by companies that will benefit from their results. Dr. Tim Noakes is famous for questioning Gatoradeâs science-based recommendations about the benefits of consuming Gatorade. And like that, examples are plenty.
Running on empty has its scientifically proven benefits (Image by ChatGPT)
We tend to forget that humans have been running for thousands of years. Hunted gatherers did so for hours while chasing an animal until it collapsed. Yet, they were able to pick it up and take it home to feed their families. They didnât carry water packs to replenish every drop of sweat. They didnât carry chews or gels to replace every calorie they burned.
Sure, we have evolved in those thousands of years. The bushmen of the Kalahari were not used to spending their day under air conditioning, sitting in front of a computer, or wearing shoes before they went hunting. But we havenât entered devolution either. Our bodies were built to withstand a certain level of dehydration and caloric deficit.
I want to leave no room for doubt that I am not advocating against electrolyte replenishment, chews, gels, or any other product. God knows I could not have finished my last few marathons without the help of Maurten gels. What I am advocating against is their overuse, to the point where our bodies become unable to learn how to use their own resources.
Running on an empty stomach is not a fad passed around by social media influencers. Based on the article in question and the study on which it was grounded, it is a well-rounded premise that âfasted cardioâ and âlow-glycogenâ training are similar but distinct practices that can offer real metabolic advantages if done right.
While skipping breakfast can be beneficial, you don’t have to do it for every run (Photo Pexels)
Mestel brings in Professor Richard J. Bloomer, Dean of the College of Health Sciences at the University of Memphis, to clarify the lingo. According to him, a âfasted stateâ can simply mean not eating for 10â12 hours, like overnight. But low-glycogen training goes further. It implies depleting your muscle glycogen stores, typically by limiting carbs over a longer period. Both approaches can shift your bodyâs fuel source away from sugar and toward fat, especially during lower-intensity sessions.
According to the study, these are some of the benefits:
Fat Adaptation: By skipping that pre-run snack or breakfast, your body is nudged into burning fat for fuel. Studies cited in the article showed that both men and women increased fat oxidation after exercising in a fasted state. Simply put, youâre teaching your body to tap into a steadier, more abundant fuel source.
Less Stomach Drama: Fasted runs can reduce gastric discomfort for those with fussy guts. No food means nothing sloshing around in there. Itâs a win for morning runners whoâd rather not eat at 5:00 AM just to avoid bonking at 6:00.
Convenience: This one isnât science; itâs life. Rolling out of bed, lacing up, and getting it done before breakfast is just easier sometimes.
The science goes even deeper. In a 2010 study from the Journal of Applied Physiology, Beneficial Metabolic Adaptations Due to Endurance Exercise Training in the Fasted State by Van Proeyen et al., this wasnât anecdotal evidence; it was a tightly controlled experiment. Two groups trained identically on bikes for six weeks. One ate carbs before and during workouts; the other trained fasted.
The result? While both groups got fitter, the fasted group showed superior metabolic adaptations. Their muscles improved at burning fat, their ability to use stored fat (even deep in the muscle) improved, and they kept blood sugar stable over long workouts. The carb-fed group? They didnât show those perks.
Conclusion
It is not about skipping breakfast forever or starting every workout on an empty stomach. But if you mix in a couple of easy runs each week without eating beforehand, especially when effort is low and stakes are even lower, your body might thank you. Youâll become more metabolically flexible, able to use fat when needed and carbs when it matters most.
Donât go overboard. Itâs about teaching your body to adapt so it can rise to the occasion, whether chasing a PR or just running for joy.
Curious to try it? Leave a comment and let me know your experience. And donât forget to subscribe to the Foultips.Run newsletter by clicking the button below.
