Is 1:57 Next? Chasing a Prediction.
- Paul Russhard
- Jun 6
- 4 min read
This year's London Marathon finally saw two men break the historic 2-hour barrier—a phenomenal achievement that will rightly go down in sporting history. Sabastian Sawe crossed the finish line first in a mind-blowing 1:59:30, officially becoming the first person to break two hours in open race conditions. He was closely followed by Ethiopia's marathon debutant, Yomif Kejelcha, who finished in 1:59:41. Both men were wearing Adidas Adizero Adios Pro Evo 3 super shoes. Following such a tremendous milestone, it is easy to look at the shoes and attribute the entire breakthrough to engineering. But shoes cannot run races alone; they require world-class runners to put them on.
Looking at the race in more detail, Sawe executed an incredible negative split, running the first half in 1:00:29 before a jaw-dropping 59:01 second half. He hammered out a ridiculous 27:36 ten-kilometre split between 30K and 40K. Then, in order to finally break Kejelcha, he ran the final 2.195 kilometres at a blistering 13:19 5K pace! It was faster than anyone has ever run that segment of a marathon before.
For context, this year's Great Manchester Run 10k was won by Selemon Barega in 27:37, one second slower than Sawe ran the 30-40k split! (Yes, Barega was also wearing a brand of super shoes, and yes, he is a world-class runner—he had a glittering track career including winning gold in the 10,000 metres at the 2020 Tokyo Olympics, before making an impressive transition to the roads).
It was all predicted, though...
Dr. Michael Joyner mathematically proved a sub-2-hour marathon was possible back in 1991. Joyner proposed that human endurance performance rests on three core metrics:
VO2 Max: The size of the aerobic engine, measuring the maximum volume of oxygen the body can utilize per minute.
Lactate Threshold: As it is related to the fraction of VO2 max that can be sustained for a long duration, without the rapid accumulation of fatigue.
Running Economy: A measure of how much oxygen it costs to maintain a specific speed.
Joyner argued that if a hypothetical athlete possessed values for all three metrics in the highest percentiles, their theoretical marathon time could be an astonishing 1:57:58.
This was met with a lot of scepticism at the time. His model assumed that extremely high values of VO2 Max, lactate threshold, and running economy could coexist in a single athlete. In reality, that is incredibly unlikely. Those with the highest VO2 Max (the biggest engines) are not naturally the most economical runners. Think of car engines: the bigger ones are not as fuel-efficient as the smaller ones. Of course, it is all relative; compared with the average runner, elite marathoners have massive engines with an average VO2 Max of around 75 ml/kg/min, though significant variation exists between individuals.
Enter the Super Shoes…
By utilizing super shoes, a runner with an incredibly high VO2 Max is no longer constrained by a reduced relative running economy.
These shoes are constructed with ultra-lightweight super foams that compress and return up to 85–90% of the energy stored during foot strike. They are assisted by a carbon stiffening element—in the latest Adidas shoes, this takes the form of an incredibly lightweight carbon-fibre infused ENERGYRIM that runs around the perimeter of the foam rather than a traditional flat plate. This massive energy return drastically improves running economy. Because the amount of oxygen a runner must consume to maintain a given speed is lower, they can run at a slightly higher velocity for the exact same oxygen cost. The economy-to-speed benefit is not a perfect 1:1 ratio though because of an increase in air resistance, especially at higher speeds.
The shoe design also relieves some of the physical load from the muscles, joints, and tendons. This means faster racing, higher-intensity training sessions, and better recovery times. Sustained, high-quality training paired with rapid recovery is what ultimately drives chronic physiological adaptations. The mechanical assistance pushes training and racing thresholds upward, allowing all three pillars of endurance performance put forward by Dr. Michael Joyner in 1991 to finally coexist on race day.
While technological innovation is just as central to endurance sports as advancements in training, nutrition, and recovery, there is a strong argument for stricter regulation. On the track, World Athletics regulates footwear, capping stack heights at 20mm for running events. On the roads, however, the limit is double that at a massive 40mm. With this looser road regulation, it is unfortunately inevitable that we are starting to talk about "pre-super shoe" and "post-super shoe" eras.
Ultimately, breaking the two-hour barrier required the perfect storm: world-class human engines pushing their own and each other’s physical limits, extreme nutritional preparation, ideal weather conditions, and cutting-edge footwear engineering. These athletes will rightly go down in history. Super shoes did not run the race for them, but they did tilt the equation in their favour, allowing them to maintain a blistering pace without their running economy falling apart. Now that this historic barrier has officially fallen, will we see an even quicker time in Berlin later this year? London was never considered the ideal course for a sub-2-hour attempt, so if the conditions are right in Germany, we might just see a time that edges even closer to Joyner’s 35 year old prediction.
If you are interested and want some more information.....
A more up-to date paper from Joyner with some information on the relationship between VO2max and economy.
This is really geeky but it’s the maths behind the original prediction.
Some details about the extent of Sawe’s nutritional preparation.
A detailed review of super shoes
