Finding The Point Of Diminishing Return: A Partnership Between Athlete And Coach
The coach and athlete work together to determine the point of diminishing returns. Coach Arthur Lydiard and Runner Peter Snell made a great team. Snell won three Olympic Gold Medals and set several world records.
Photo Credit: Andy Yelenak
The Point of Diminishing Returns Revisited:
Running's Most Important — and Most Misunderstood — Law
By Coach Larry Weber | coachweber.org
I want to be honest with you before we start. I am not writing this article as someone who has it all figured out. I am writing it as a coach who has made plenty of mistakes, learned slowly, and been humbled by this sport more times than I can count.
Over the past four decades, I have had the privilege of working with a wide range of athletes — high school runners, a Paralympic world record holder, a masters world record holder, age-group record holders, USA Olympic Marathon Trials qualifiers, post-collegiate Kenyan runners including a former NCAA Champion, and high school teams that have won sixteen state athletic championships and three academic championships across two schools in cross country and track and field.
That variety has taught me one thing above all else: no two runners are the same, and no single training plan fits everyone.
The principle that ties all of that together is what I and others call the Point of Diminishing Returns. It is the most important law in distance running training, and it is the one broken most often — sometimes by runners, sometimes by coaches.
The idea is simple. Every runner has a personal training ceiling. Push too far past it, and you break down. Stay too far below it, and you leave potential untouched. The job of coach and athlete together is to find the zone that drives real improvement — not too much, not too little. Just right.
Finding that zone takes time, honesty, and humility. It looks different for every person who has ever laced up a pair of running shoes.
The key that opens the running vault is not a method. It is knowing one runner at a time.
The Greatest Coaches Understand that training strategies do not work the same way for everyone.
Arthur Lydiard was a New Zealand coach who spent decades figuring out how to build distance runners the right way. His most famous athlete, Peter Snell, won three Olympic Gold Medals and set multiple world records. What Lydiard understood — and what took him years of trial and error to discover — was that the amount of training a runner could handle was individual. More was not always better. Better was better.
Joe Vigil, who passed away in July 2025 at the age of 95, spent fifty years coaching some of America's finest distance runners. He built Adams State University into a national championship program, coached Olympians, and was named National Coach of the Year fourteen times. He believed that a great running coach is really a life coach first. What he meant was this: training a runner in isolation from the rest of their life — their stress, their sleep, their relationships, their spirit — is a losing proposition. If the whole person is not considered, the training plan is irrelevant.
Jack Daniels, who passed away in September 2025 at the age of 92, was named by Runner's World as the world's best running coach and was one of my mentors. He spent decades building practical systems for training runners at the right intensity. His central insight — before he had a name for it — was the same: train at the right level for each runner, and the results follow. Push past that level, and you pay for it.
Brother Colm O'Connell, the Irish missionary widely known as the Godfather of Kenyan Running, arrived at St. Patrick's High School in Iten, Kenya, in 1976 with no coaching background whatsoever. He has since produced twenty-five world champions and four Olympic gold medalists. His philosophy has always centered on one idea: adapt your coaching to suit the individual runner, not the other way around.
Lydiard, Vigil, Daniels, and Brother Colm O'Connell all arrived at the same place through very different roads. The amount and training a runner can absorb is not written in a magazine or a podcast. It is discovered through relationship, observation, and time.
I feel the same way and take a very similar approach as the coaches listed above in my own unique way.
The Norwegian Method and Double Threshold Training: A Plain-Talk Explanation
Before I explain this, let me be clear: I did not invent any of this. I learned it, studied it, and have tried to apply it wisely. What I have seen in my years of coaching is that even the best systems only work when they are matched to the right athlete.
In recent years, the training approach that has generated the most excitement in distance running is called the Norwegian Double Threshold method. It is associated with Norwegian runners — particularly the Ingebrigtsen family — who have dominated middle-distance and distance running at the Olympic level. Jakob Ingebrigtsen won gold in the 1500 meters and the 5,000 meters at the Olympics. The method is based on decades of research and self-experimentation by a Norwegian physician and former elite runner named Marius Bakken.
What Does Double Threshold Actually Mean?
Here is the plain-talk version.
When you run, your muscles produce a substance called lactate as a byproduct of the energy process. At easy paces, your body clears lactate as fast as it makes it — no problem. As you run faster, lactate builds up. At a certain pace, your body reaches what scientists call Lactate Threshold 1 (LT1). This is the first point where lactate starts rising noticeably above its resting level. Run faster still, and you hit Lactate Threshold 2, or LT2. This is the pace at which lactate starts accumulating faster than your body can clear it. Once you cross LT2, you are running on borrowed time.
Think of LT1 as a brisk, sustained climb up a long hill — productive, repeatable, and hard but manageable. Think of LT2 as sprinting up that same hill — powerful, but you cannot do it twice in a row without paying a high price.1
The Norwegian method trains primarily in the zone between LT1 and LT2. The key insight is this: if you stay below LT2, you can do quality work twice in one day — once in the morning, once in the afternoon — without destroying your body's ability to recover. Over time, this allows you to accumulate a large amount of productive, hard work without the crushing fatigue that comes from going too hard too often.
Marius Bakken spent decades developing this framework. Working simultaneously as a physician and a competitive runner, he used a portable device to test his own blood during training — more than 5,500 times across his career — to understand precisely what was happening in his body at different running paces.2 What he found became the foundation of a system that produced Jakob Ingebrigtsen's multiple world records and Olympic gold medals.
During Ingebrigtsen's base training phases, the weekly structure included 110-120 miles and six quality sessions. Three or four of those were lactate-controlled threshold sessions, and two days featured morning-and-afternoon doubles — each session kept below the LT2 ceiling. One day included hills. Long, easy runs filled the rest of the week.3
Not despite the conservative training structure — because of it.
When a coach or athlete comes to me excited about the Norwegian method — or any other training system — I ask one question: How do you know it works for this specific person?
Some athletes respond very well to double threshold training. Their aerobic engines are built for high-volume, controlled-intensity work. They recover well between sessions, adapt steadily, and race brilliantly. For them, this approach can be a revelation.
Others do not respond the same way. Some runners need more VO2 max work — that is, harder, shorter intervals that push them close to their maximum capacity. Others do better with traditional tempo runs: a sustained, continuous effort at a hard-but-manageable pace, rather than broken intervals. Some athletes, particularly those built more for power and speed, need the faster-pace challenge that double threshold sessions do not provide.
I have coached a Paralympic world record holder who needed training adjustments that no published program had ever addressed. I have worked with a master's world record holder whose body recovered very differently at 45 than at 25. I have coached post-collegiate Kenyan runners remotely with lactate profiles most likely unlike anything in the American running literature, and Olympic Trials qualifiers whose responses to the same workout were nearly opposite.
The lesson is always the same: the method is a starting point, not the answer.
What Science Is Now Telling Us About DNA
For most of coaching history, we said things like every runner is different without really understanding why. Science is now beginning to fill in that picture. The findings matter, but they also require humility — because the more we learn, the more we realize how much we still do not know.
How Much Does Genetics Actually Matter?
Research consistently shows that, on average, roughly 66% of the variation in athletic ability between people is explained by genetic factors. The remaining 34% comes from training, nutrition, sleep, environment, and life circumstances.4 That is a large number. It does not mean training is unimportant. It means the athlete's starting point, their ceiling, and how they respond to different types of work are all shaped — in significant ways — by what they were born with.
The capacity to use oxygen efficiently — what scientists call VO2 max — has a heritability of roughly 50%, meaning about half of an athlete's aerobic ceiling is determined by genetics. Muscle fiber type distribution, meaning the ratio of slow-twitch to fast-twitch fibers (which profoundly shapes how an athlete responds to training), has a heritability of 40 to 50%.5
Put plainly: two runners who train identically, eat identically, and sleep identically may still respond to the same workout in very different ways. That is not a character flaw. That is biology.
Two Genes That Researchers Study in Distance Runners
Scientists have now identified more than 250 genetic variations — single-letter differences in the DNA code, called SNPs — associated with athletic performance.6 Among these, two have received the most rigorous study in the context of distance running.
The first is a gene called ACTN3, sometimes nicknamed the speed gene. It controls the production of a protein found specifically in fast-twitch muscle fibers — the fibers responsible for explosive, powerful movements. One version of this gene (the R variant) produces the protein and tends to be more common in sprinters and power athletes. Another version (the XX genotype) produces no protein at all.
Researchers have found that the XX genotype is more common among endurance athletes than among power athletes. However, this advantage is not as clear-cut as the R variant's advantage in power sports.7 Roughly 18% of people with European ancestry carry the XX version — a figure that varies significantly by ethnic background and does not apply to all populations.8
The second is a gene called ACE, which affects how the heart and blood vessels respond to physical stress. One variant (the I allele) is found more often among elite distance runners. A 2024 research review combining results from 137 studies found a meaningful statistical link between this variant and elite endurance athlete status.9 However, a separate study of 698 endurance athletes found no connection between this gene and actual personal-best race times at any distance.10 The honest takeaway: the ACE research is promising, but genuinely mixed. No single gene variant tells the full story.
No gene determines whether a young runner will become a champion. But genetics shape the ground on which every training plan is built.
Let me be direct about the limits of this research.
It does not mean coaches should run genetic tests on young athletes to decide who has potential. I would never do that for any reason. The scientific community is clear: using genetic testing for talent identification is not yet supported by sufficient evidence and raises serious ethical concerns, especially when applied to young people.11
What the science does tell us, though, is that individual response to training is biologically real. When one athlete thrives on double-threshold sessions, and another breaks down during the same workout, there may well be a genetic explanation rooted in muscle fiber composition, oxygen efficiency, or cardiovascular architecture. When a runner who trains hard sees only modest improvement while a teammate on the same plan runs a personal best, that gap is not simply a matter of effort or attitude. It may be written into their physiology.
Researchers are now developing approaches that combine genetic data with training history and physiological measurements to build more individualized programs. This field is young, but the direction is clear: personalization is the future of endurance training.12
This is exactly what experienced coaches have long known. Science is now providing the language to explain it.
Strategy: What Experience Actually Teaches
I have been doing this long enough to be humbled regularly. I have coached a Paralympic world record holder who rewired much of what I thought I knew about training load. I have worked with a master's world record holder who proved that adaptation does not stop with age — it just changes. I have had Olympic Trials qualifiers who responded to low-volume, high-intensity work in ways that contradicted everything I expected going in.
Sixteen state high school championship teams have taught me more about patience, customization, and the unpredictability of athletic development than any book or seminar ever could. I am grateful for every one of those seasons — including the ones where I got it wrong.
Here is what the accumulated experience has taught me: There Is No Substitute for Time.
You cannot know an athlete's Point of Diminishing Returns until you have watched them train through enough cycles to see the patterns emerge. A coach who has worked with hundreds of athletes over many years develops an eye for subtle signals — changes in mood, stride, and how an athlete carries themselves at the end of practice — that no formula can replicate.
That takes time. It also takes humility, because what you think you know about a particular runner will be proved wrong more than once.
Honest Communication Is Not Optional
The most important conversations in coaching happen when an athlete is brave enough to say that something is not working. Maybe the training load is too high. Maybe the type of workout does not feel right. Maybe something is going on in the rest of life that is affecting recovery.
Those conversations require trust, and trust is built slowly. A coach who makes an athlete feel safe enough to be honest is giving them something more valuable than any workout.
The Courage to Change Course
One of the hardest things in coaching is adjusting the plan when it is not working. The instinct says to add more miles. Common wisdom says to push through. The Point of Diminishing Returns says: stop, look honestly at what is happening, and be willing to try something different.
For some athletes, that means cutting back on intervals and adding more threshold work. For others, it means the opposite. For some, double-threshold training is exactly the right fit. For others, it is not the right fit — for now, or perhaps ever.
The courage to make those adjustments without ego, and without fear of going against the trend, is what separates good coaches from great ones.
Doing more than you need is not dedication. It is a recipe for injury and burnout.
The Point of Diminishing Returns is not a soft suggestion. It is an immutable law of training — as real and fixed as gravity. Step over the edge of your limits, and you will not make it to the starting line. Stay within them, pushing right up to but not past the boundary, and the results will follow.
Lydiard discovered this through trial and error with Peter Snell. Joe Vigil spent fifty years embodying it at every level of the sport. Jack Daniels built an entire system around finding the right training intensity for each runner. Brother Colm O'Connell figured it out on a dirt track in the Kenyan highlands with no coaching background and no manual to follow. Marius Bakken tested it on himself thousands of times with a lancet and a portable blood analyzer. All of them arrived at the same place.
The method you use matters less than whether the method fits the person you are coaching.
When someone tells me about the latest training technique from a podcast or a magazine, I always ask: How do you know it will work for this person's unique DNA, history, and life? How do you know if it matches this runner?
That question does not have a shortcut. It is answered over time, with care, through honest conversation, and with a willingness to be wrong and start again.
I have coached a Paralympic world record holder. I have coached a master's world record holder who had things to teach me about determination and patience. I have coached Olympic Trials qualifiers who reached levels that surprised even them. I have coached sixteen state championship teams.
In all of it, the most important thing I did was not choose the right workout. I knew the person well enough to choose the right workout for them.
One runner at a time. One experiment at a time. One honest conversation at a time. Presence is not optional with the athlete you coach. You actually have to know them, and yes, see them regularly, to do the best job.
Being a good life coach to an athlete who personalizes training and truly cares about a person's overall well-being is more important than understanding every detail of physiology.
That is the only training plan that always works.
A final note: Please do not use the principle of diminishing returns as an excuse to avoid hard work. You must train hard and smart. Smart means finding your individual limits—not avoiding them, but locating them precisely through experience, experimentation, and the guidance of a coach who cares enough to keep learning alongside you, no matter how many years they have been at it.
Blessings,
Coach Weber
Philippians 4:13
Endnotes
1. Faude O, Kindermann W, Meyer T. "Lactate threshold concepts: how valid are they?" Sports Medicine. 2009;39(6):469–490. This widely cited peer-reviewed review establishes the distinct physiological meaning of LT1 (approximately 2 mmol/L — the first sustained rise in blood lactate above resting baseline) and LT2 (approximately 3.5–4.5 mmol/L — the maximal lactate steady state, beyond which accumulation outpaces clearance). The double threshold method keeps sessions intentionally below LT2 to limit fatigue and allow quality work to be repeated within a single day and across multiple days per week.
2. Bakken M. The Norwegian Method Applied: Threshold Training and Intensity Control for Faster, More Durable Running at Every Level. 2025. The 5,500-test figure comes from Bakken's own published account at mariusbakken.com: "After I started using the lactate meter, I tried to systematically monitor, structure, change, and preserve training as much as possible, resulting in over 5,500 lactate acid tests." Confirmed independently by Athletics Weekly (May 2026), which reported that Bakken "has spent several decades experimenting with the Norwegian Method, which includes conducting around 5,500 lactate tests." Bakken was a two-time Olympian and set the Norwegian national record at 5,000 meters (13:06.49), a mark that stood for more than 20 years.
3. Kelemen O, Benczenleitner O, Toth L. The Norwegian double-threshold method in distance running: Systematic literature review. Scientific Journal of Sport and Performance. December 2023. This systematic review documents the base-phase training structure used by the Ingebrigtsen athletes: 110–120 miles per week, six quality sessions weekly, with two double-threshold days per week (one threshold session in the morning, one in the afternoon, each kept within the LT1–LT2 intensity range), and threshold session volume of 8–12 km per session.
4. Semenova EA, Hall ECR, Ahmetov II. Genes and Athletic Performance: The 2023 Update. Genes. 2023;14(6):1235. doi:10.3390/genes14061235. PMC10298527. The 66% heritability estimate for athletic status is one of the most consistently replicated findings in sports genomics and is confirmed across multiple independent reviews, including Ahmetov II and Fedotovskaya ON. Current Progress in Sports Genomics. Advances in Clinical Chemistry. 2015;70:247–314.
5. VO2 max heritability (~50%): Bouchard C et al. The HERITAGE Family Study: aims, design, and measurement protocol. Medicine and Science in Sports and Exercise. 1995;27(8):1260–1269. This landmark multi-year family study remains the primary source for VO2 max heritability estimates. Muscle fiber type heritability (40–50%): Simoneau JA, Bouchard C. Genetic determinism of fiber type proportion in human skeletal muscle. FASEB Journal. 1995;9(11):1091–1095.
6. Semenova EA, Hall ECR, Ahmetov II. Genes and Athletic Performance: The 2023 Update. Genes. 2023;14(6):1235. As of May 2023, 251 DNA polymorphisms had been associated with athlete status, of which 128 were confirmed in at least two independent studies: 41 endurance-related, 45 power-related, and 42 strength-related.
7. El Ouali EM, et al. A Systematic Review and Meta-analysis of the Association Between ACTN3 R577X Genotypes and Performance in Endurance Versus Power Athletes and Non-athletes. Sports Medicine — Open. 2024;10:37. doi:10.1186/s40798-024-00711-x. 25 studies, 14,541 participants. The RR genotype and R allele were significantly overrepresented in power athletes. The XX genotype appeared at a higher frequency in endurance athletes than in power athletes (OR 0.63; 95% CI 0.52–0.76, p<0.00001), but the endurance advantage of XX is less statistically definitive than the power advantage of RR. Importantly, the Genathlete Study (316 elite male endurance athletes, VO2max ~79 ml/kg/min; PMID 20845221) found no significant difference in ACTN3 R577X genotype between elite endurance athletes and sedentary controls, suggesting that the XX genotype may be additive to — rather than decisive for — endurance performance.
8. The approximately 18% XX genotype frequency applies specifically to populations of European (Caucasian) ancestry and should not be generalized. This figure varies significantly by ethnic background: African-ancestry populations typically show much lower XX frequency (approximately 3–10%), while some Asian populations show higher rates (approximately 16–25%)—primary sources: Genathlete Study, PMID 20845221; Yang N et al. ACTN3 genotype is associated with human elite athletic performance. American Journal of Human Genetics. 2003;73(3):627–631.
9. Varillas-Delgado D, et al. Role of the ACE I/D Polymorphism in Selected Public Health-Associated Sporting Modalities: An Updated Systematic Review and Meta-Analysis. Nutrients. 2024;16(22). PMC11593961. 137 studies screened. A significant association was found between the ACE II genotype and elite endurance athlete status compared with healthy inactive controls (OR 1.54; 95% CI 1.24–1.91) and compared with elite power athletes (OR 1.56; 95% CI 1.07–2.28). Supporting study: Saunders CJ et al. The angiotensin converting enzyme I/D polymorphism in long-distance runners. European Journal of Applied Physiology. 2006;98(2):178–183. PMID 16998460: a statistically significant excess of the ACE I allele was found among top-150 marathon finishers (p<0.01).
10. Webborn N, et al. No association between ACTN3 R577X and ACE I/D polymorphisms and endurance running times in 698 Caucasian athletes. BMC Genomics. 2018;19(1):13. doi:10.1186/s12864-017-4412-0. The study collected 1,064 personal-best running times at 1500m, 3000m, 5000m, and marathon distances from athletes across six countries (Australia, Greece, Italy, Poland, Russia, and the UK). No significant association was found between the ACE I/D genotype and performance at any distance. This finding underscores the article's core argument: population-level genetic signals do not reliably predict individual performance and cannot substitute for individual athlete assessment.
11. For a review of ethical concerns surrounding genetic testing in sport, see: Wackerhage H et al. Recommendations for Reporting of Genetic Association Studies in Sport and Exercise Science. Journal of Sports Sciences. 2009;27(11):1107–1110. Also: The Development of a Personalized Training Framework: Implementation of Emerging Technologies for Performance. PMC7739422. Current expert consensus holds that genetic testing lacks sufficient evidence for use in talent identification and raises particular ethical concerns when applied to youth athletes.
12. Wang Z, Zhang Y. Deep learning for genomic insights into athletic performance in sports education. Frontiers in Genetics. 2026. doi:10.3389/fgene.2026.1766127. This paper discusses the application of deep learning models to large genomic datasets to identify SNPs correlated with VO2 max, muscle fiber composition, and injury susceptibility, and the development of individualized training frameworks that combine genetic data with physiological and training history measurements.
One of the world's best coaches, Dr. Jack Daniels, spoke with student-athletes at the Jim Ryun running camps. Transparency and two-way communication are hallmarks of great coach-athlete relationships.
Photo Credit: Jim Ryun Running Camps
About the Author
Coach Larry Weber is the author of Jesus on the Track: A Christian Athlete's Guide to Handling Hard Days, Building Mental Toughness, and Growing in Faith. A 2026 Washington State Cross Country Coaches Hall of Fame inductee, Weber has built 13 state cross-country championship programs, coached USA Olympic Marathon Trials qualifiers, and is the record holder in the Original Ultimate Runner Competition (10 k, 400 meters, 100 meters, a mile and marathon all ran on the same day). He writes about faith, running, and formation at coachweber.org.
Jesus on the Track is a short read available on Amazon.com: Amazon.com: JESUS ON THE TRACK: A Christian Athlete's Guide to Handling Hard Days, Building Mental Toughness, and Growing in Faith eBook : Weber, Larry: Kindle Store
Jesus on the Track is also available in Paperback.
Coach Weber is also the author of the just released book: Mile Three: How the Hardest Part Builds the Best Kids. There is a paperback and kindle version.
Coach Weber's training philosophy is embedded in Mile Three and represents his life work. It is a longer book around 200 pages that discusses the long term positive results of distance running over a lifetime.