Sebastian Sawe — How Did He Break the Two-Hour Barrier?
Kovács Ferenc Soma, Hungarian national record holder in middle-distance running
April 26, 2026 will undoubtedly go down in the golden pages of athletics history. On that day, Kenya’s Sebastian Sawe became the first athlete to run a sub-two-hour marathon under fully legal conditions at the London Marathon. His time of 1:59:30 made him only the second runner in history to complete the 42.195-kilometre distance in under two hours. The first was his compatriot Eliud Kipchoge, who ran 1:59:40 in Vienna’s Prater Park in 2019, albeit under unofficial conditions. In that race, pacemakers rotated every five kilometres and stopped to rest between their assigned sections. This is explicitly prohibited under World Athletics (WA) regulations, meaning the performance could not be officially ratified. This raises an obvious question: how was Sawe able to run even faster than Kipchoge’s time under completely legal conditions? In this article, I examine the key details of his preparation and racing strategy that enabled him to deliver a seemingly superhuman performance on the streets of London.
The 31-year-old athlete comes from Uasin Gishu County in Kenya’s Rift Valley region. The city of Eldoret, home to one of Kenya’s legendary running hubs, is located here. Uasin Gishu had already produced countless world-class runners before Sawe. This is not only due to the excellent genetic background of the local population, but also because the county sits at elevations ranging from roughly 1,500 to 2,700 metres above sea level. Those living there are therefore constantly exposed to the physiological effects of altitude. Sawe could consequently approach the London Marathon with both an excellent genetic background and consistent altitude exposure. These factors alone, however, still do not explain why he was so dramatically faster than the other East African runners. So let’s take a closer look at his preparation.
Sawe’s training is overseen by Claudio Berardelli. Interestingly, his preparation was disrupted by several injuries: during the winter he suffered a stress fracture in his foot and also dealt with back problems. He was ultimately able to begin serious training in February, reaching 240 kilometres per week during his most demanding periods. Berardelli structured his training into ten-day cycles that would seem almost impossible to execute for most recreational runners. The first day of the cycle is typically a 25–40 kilometre long run. Before the race, for example, Sawe completed two demanding 40-kilometre long runs: one in 2:08 and another in 2:04. Days two and three involve lighter training, usually 20 kilometres in the morning and another 10 kilometres in the afternoon. On day four, he performs a short interval or fartlek session covering 8–16 kilometres, while day five consists of another set of recovery runs. On day six, he completes a long interval session with a total distance of 18–25 kilometres, followed by another easy day. Day eight is dedicated to hill training, while days nine and ten again focus on recovery.
The demanding training ultimately proved extremely effective. Sawe has raced four marathons so far and has won all four, including victories in Valencia, London and Berlin. It is therefore no coincidence that he had already attempted to break the two-hour barrier in Berlin last September. His 2:02:16 performance was the fastest time in the world that season. Sawe had therefore been targeting the two-hour barrier for quite some time. In London, he also faced an exceptionally strong field: Kejelcha, Kiplimo, Amos Kipruto, Tamirat Tola and Deresa Geleta stayed with him until the 25-kilometre mark. At that point, however, the final pacemaker, who had led the first half marathon in 60:29, stepped off the course, and Sawe pulled away from his rivals. Interestingly, his second-half split of 59:01 was faster than Conner Mantz’s American record of 59:17 for the half marathon. Even more impressive was his final 12 kilometres: he ran 13:54 between 30 and 35 kilometres, followed by 13:42 between 35 and 40 kilometres, and covered the final 2.2 kilometres in just 5:51. And here is another astonishing statistic: he ran the 24th mile in 4:12, the fastest single-mile split ever recorded within a marathon. Alongside his consistent preparation, several technological innovations also contributed to Sawe making history in London.
Let’s start with the shoes. Four of the top five finishers raced in the Adidas Adizero Adios Pro Evo 3. According to Adidas, it is the world’s first marathon racing shoe weighing under 100 grams. That represents roughly a 30% reduction in weight compared with the previous, second-generation model. Few previous developments have achieved a weight reduction on this scale. The shoe has a stack height of 39 mm at the heel and 36 mm at the forefoot, meaning it complies with World Athletics’ maximum permitted stack height of 40 mm. As a result, records run in the shoe can be officially ratified. Interestingly, the shoe is now also available for purchase on Adidas’ website for $500, making it one of the most expensive running shoes ever produced. According to the brand, the upgraded Lightstrike Pro Evo foam provides 11% greater energy return in the forefoot than the previous model, resulting in a 1.6% improvement in running economy. Adidas engineers also managed to reduce the weight of the foam by almost half when developing the third generation.
The weather also played a significant role in helping the runners on race day. Temperatures were around 10°C at the start and rose to approximately 15–18°C by the finish. Although the days leading up to the marathon had been particularly warm, heavy cloud cover on April 26 significantly reduced solar radiation. Even more importantly, a tailwind assisted the runners over a substantial portion of the course. The first three finishers also defied a trend that has emerged in recent years: the average pace of the leading men in London has been around 1.5 seconds per kilometre slower than in Berlin, primarily because of the greater number of turns.
The biggest game changer, however, was undoubtedly the revolution in race-day fueling. Sawe is sponsored by the popular sports nutrition brand Maurten. The company’s research team monitored Sawe’s training sessions in Kenya for a month, attempting to create conditions that closely replicated his race-day fueling protocol. On race day, Sawe began taking 160 ml of Maurten Drink Mix 320 every five kilometres from the 5-kilometre mark onward. He also consumed a Gel 100 containing 25 grams of carbohydrate five minutes before the start. This meant he was taking in approximately 40 grams of carbohydrate every 14 minutes. And if that wasn’t enough, he consumed a Gel 100 Caf 100 at 20 kilometres, which contains 100 mg of caffeine in addition to its 25 grams of carbohydrate. By halfway, he had therefore fueled six times, consuming a total of 210 grams of carbohydrate.
Maurten’s hydrogel technology made it possible for 90–120 grams of carbohydrate from this intake to be absorbed and utilized during the first hour of the race without causing gastrointestinal problems. To understand how significant this represented for sports nutrition, it is worth looking at the historical context. Before 2004, athletes primarily relied on maltodextrin (glucose) for race fueling. Because the maximum capacity of the SGLT1 glucose transporter in the small intestine was approximately 60 grams per hour, consuming more glucose than this could cause significant gastrointestinal problems. As a result, athletes generally consumed no more than 60 grams of carbohydrate per hour to avoid stomach issues, since they were unable to utilize much more than that anyway. Consequently, almost everyone experienced the so-called “wall” toward the end of the marathon, causing a dramatic decline in performance. For decades, sports nutritionists considered this unavoidable and simply part of the marathon experience. In light of this, it can be argued that one of the most important reasons Sawe was able to break two hours was that he simply never hit the wall during the race. In fact, he became faster as he approached the finish, helped both by his carefully designed fueling strategy and the effects of caffeine.
Although Sawe’s genetics, work ethic and preparation are all exceptional, I honestly doubt that these factors alone explain the more than one-minute difference between Sawe’s time and Kiptum’s former world record of 2:00:35. Kiptum was born in the neighbouring county and also trained at altitude in Kaptagat. Given this, it is reasonable to assume that the two runners had broadly similar genetic backgrounds. Kiptum’s weekly mileage also fluctuated between 250 and 300 kilometres, meaning he actually trained at an even higher volume than Sawe. In other words, the statistically significant difference is much more likely to be explained by the new shoe technology and the perfected fueling strategy.
Kiptum raced in a prototype of the Alphafly 3, the Nike Dev 163 Prototype, which weighed 212 grams. Sawe’s Adidas Adizero Adios Pro Evo 3, by comparison, weighs just 97 grams. The 115-gram difference may not seem significant at first, but over a marathon it paints a very different picture. Consider a 2023 orthopaedic study examining the top eight finishers in the Tokyo Olympic marathon. The researchers found that the leading runners averaged 185.5 steps per minute (Gamez-Paya et al., 2023). Over a two-hour marathon, that amounts to a total of 22,260 steps. At that step count, the 115-gram difference in shoe weight translates into more than 2.5 tonnes of cumulative additional shoe mass carried by Kiptum compared with Sawe’s ultralight footwear. While this obviously does not mean that Kiptum performed that much more mechanical work, it illustrates just how significant a few dozen grams can become over the course of an elite marathon.
As for fueling, Kiptum’s Maurten team never publicly disclosed the Kenyan star’s exact race-day strategy, so we do not know whether he used sodium bicarbonate or consumed caffeine during the race, for example. It is reasonable to assume, however, that the Maurten team has continued refining its fueling protocol since Kiptum’s era, and that the developments of the past two and a half years have already been reflected in Sebastian Sawe’s performance.
All of this demonstrates that the modern marathon is now far more than a competition of genetics and training volume. Today, achieving world-class performance also depends on shoe technology, scientifically designed fueling strategies, analysis of weather conditions, and continuous monitoring of training. Polar sports watches can also play an important role in this process. Features such as Training Load Pro™, Recovery Pro™, and Polar’s sleep analysis system allow runners to optimize their training load and recovery based on objective data. Sebastian Sawe’s performance in London is an excellent example of how, in 21st-century endurance sport, it is no longer simply about who trains the most, but also about who can make the most effective use of the opportunities provided by sports science and technology.
References:
Gamez-Paya, J., Aladro-Gonzalvo, A. R., Gallego-de Marcos, D., Villarón-Casales, C., & Lopez-del Amo, J. L. (2023). Footstrike Pattern and Cadence of the Marathon Athletes at the Tokyo 2020 Olympic Games. Applied Sciences, 13(11), 6620. https://doi.org/10.3390/app13116620