Claire Hou

These are a multitude of aids runners use to break records.

Some said it couldn’t be done.

But on May 6, 1954, pushing through the last lap on the cinder track, 25-year-old Roger Bannister broke the finish line tape and fell into an ecstatic crowd as the clock read 3:59.4. After nine years of stagnation following Gunder Hägg’s record of 4:01.4 set in 1945, Bannister achieved what some scientists had previously believed was biologically impossible — running a sub 4-minute mile.

In the years since, breaking 4 minutes in the mile has become increasingly frequent from high school to professional runners. Currently, over 2,300 runners have run a sub 4-minute mile, and over 30 high school boys have broken this barrier. 

The current world record in the distance is held by Hicham El Guerrouj, who set the men’s outdoor world record of 3:43.13 on July 7, 1999, in Rome. While world records continue to be broken today, this progressive improvement raises two questions: Are humans reaching their physical limits? And if not, when will humans reach their limits in measurable races like the mile, the 10k or the marathon?

Breaking records with outside help

One method to set a world record is by having help. Even back in 1954 during Bannister’s first sub 4-minute mile, he had two pacers, Chris Chataway and Chris Brasher, who led him through three-and-a-half quarters — roughly 1,500 meters — of the mile. These pacers prevented him from running out too fast during the beginning of the race and ultimately allowed him to run his record-breaking time at the proper pace.

Today, pacers have become increasingly common in casual races as well. Fun runs often have pacers who help lead amateur runners to their goals, while professional athletes continue to use pacers — often with strict regulations — in pursuit of world records.

Then there are the improvements to shoes. In 2016, Nike produced the first carbon-plated supershoe — a new type of running shoe featuring a curved, spoon-shaped carbon-fiber plate nestled in a thick midsole constructed from ultralight, bouncy foam. The top three men in the 2016 Rio Olympics Marathon — Eliud Kipchoge (Gold), Feyisa Lilesa (Silver) and Galen Rupp (Bronze) — swept the podium with Nike’s early prototypes.

The following year in 2017, the shoes went on sale in public. The first model was named Vaporfly 4%, as testing at the University of Colorado determined that the shoe saved on average 4% of an athlete’s energy while running. Another study found that the foam cushion in the Vaporfly 4% — ZoomX foam — returns 87% of energy taken with each step. In a New York Times study, runners with Vaporfly shoes ran 3-4% faster than those wearing other shoes. 

A few years after Nike’s release of the Vaporfly 4%, other major brands started releasing their own versions of supershoes. These shoes all follow the similar formula of Nike’s supershoe but have been slightly tweaked for their respective audiences and distances. Some popular shoes include: Adidas Adizero Adios Pro 4 ($254.95), Asics Metaspeed Ray ($299.95), Nike Alphafly 3 ($295), Puma Fast-R Nitro Elite 3 ($299.95), Saucony Endorphin Pro 5 ($239.95) and UA Velociti Elite 3 ($250).

Supershoes are enjoying a surge in popularity. This is so much so that wearing them is the norm in high school cross country and track and field races. Even amateur weekend runners wear supershoes on recovery jogs.

One notable example of pace and technology usage occurred last July in Paris. Three-time Olympian, numerous world champion title holder and women’s mile world record holder Faith Kipyegon attempted to be the first female to break the 4-minute mile barrier in an event billed as “Breaking4: Faith Kipyegon vs. the 4-Minute Mile.”

Kipyegon was supported by 13 pacers, including two women who stayed with her until the halfway point and a five-man team — called “the shield” — who stayed in front of her, aiming to offer environmental and psychological benefits. This was meticulously calculated to not interfere with drag, as studies have shown that tucking behind two pacers can cut frontal drag — the resistance an object faces when moving through air or water — by around 33%, along with lowering oxygen cost by around 6% at race speed. Furthermore, pacers lighten the cognitive load of thinking about splits.

Kipyegon also optimized her performance through custom Victory Elite FK spikes, an “innovative, first-of-its-kind speed suit and a sports bra made of a revolutionary 3D-printed performance material.”

Despite her strong attempt, she fell short, running a 4:06.42. Even though she beat her previous world record of 4:07.64 set in 2023, the time was not eligible for record consideration because the event is considered an exhibition. Nevertheless, she remains hopeful, promising that she will attempt to break the 4-minute mark again.

“I’m tired. But I feel good, I’ve tried,” Kipyegon said in an interview after her run. “I’m so grateful, and I have proven to the world that anything is possible.”

Using biological manipulation to break records

Another method to set a world record is to improve through better training methods. If an athlete trains more effectively, eats better, improves their strategy or becomes mentally stronger, world records can also fall.

While some critics only support records broken through biological progress since they believe breaking records through outside help does not truly demonstrate human improvement, the distinction between biological and technical progress is blurry.

Performance enhancing drugs are a prime example of unnatural help  that skews an athlete’s performance and makes records much harder to quantify. The World Anti-Doping Agency bans such drugs based on concerns with doping safety, performance-boosting powers and whether they violate the “spirit of sport.” 

Consequently, professional athletes are perpetually tested for doping violations, which often ruins the excitement of a broken record, as spectators are often wary of athletes’ doping. However, testing is still crucial, as allowing doping would likely normalize the use of these drugs, further reinforcing the already aggressively competitive mindset already associated with sports.

 While editing genes to produce more red blood cells is considered doping, sleeping in a low-oxygen altitude tent to enhance production of red blood cells is allowed because it is considered a natural adaptation.

Also legal is the use of sodium bicarbonate or baking soda — called “bicarb” by runners — as a performance enhancer for runners. It buffers lactic acid during high-intensity efforts, allowing for better endurance and speed. The downside: Sodium bicarbonate commonly causes gas, bloating, increased thirst and cramps; high doses or frequent use can even lead to rare, serious side effects, such as nausea, decreased potassium levels, muscle spasms, metabolic alkalosis and high blood pressure. Despite this, many runners regularly race while using this substance, often ingesting it in a capsule, pill or hydrogel form.

Most notably, Kenyan runner Sabastian Sawe, who shattered the 2-hour barrier in the marathon and set a world record of 1:59:30 in the London Marathon on April 26, worked bicarb into his raceday nutrition plan. Hoping to peak his body to buffering capacity right at the start, Sawe took the Maurten Bicarb System over two hours before the race, as sodium bicarbonate peaks in the bloodstream 60 to 90 minutes after ingestion.

To further blur the line between outside help and biology, after the invention of supershoes and superspikes, each innovation was followed by a surge of fast times that have continued to improve. One theory is that supershoes’ thick, bouncy midsoles allow runners to train harder without getting injured. The revolutionary shoes are not only allowing people to instantly become faster; they are also allowing people to improve their biology through harder training.

Statistics about human improvement are contradictory

Starting in February 2020, 26-year-old pole Swedish vaulter Armand “Mondo” Duplanitis broke the men’s pole vault record 15 times, clearing 14 of his own world records. All-time great US swimmer Katie Ledecky has set 16 world records since 2013, holding 37 American records.

Although the exemplary achievements of athletes like Duplantis and Ledecky support the common assumption that humans are constantly breaking records, other statistics show that humans may be starting to hit real performance barriers.

Since 1968, the men’s world record in long jump has been broken only once. It occurred when Mike Powell leapt 8.95 meters at the 1991 World Championships. This has led many to think that humans have reached a peak in long jump and further improvements are nearly impossible, but this is anyone’s guess.

Some scientists have modeled the chances of breaking records on a mathematical concept called the harmonic series: the infinite series formed by the sum of the reciprocals of all positive integers. While the terms being added get smaller and approach zero, the total sum grows infinitely, similar to how scientists predict that the frequency of record-breaking is expected to dramatically drop over time but still continue.

Another reason improvements could slow down in the coming decades is climate change. Three-fourths of athletes report that climate change and rising temperatures are negatively affecting their health and competition performance — for instance, their ability to run their fastest time in a marathon.

Taking the long view 

So is the human race really reaching its limits? The answer is that it is too soon to tell. While some studies have argued that across a range of track and field events, humans are at or near peak physical performance, others demonstrate how human performance has yet to peak.

Rapid technological advancement further blurs the line between the human race becoming more advanced and outside help. In the end, only time will tell if humans will keep breaking records or whether some records, like the previously believed in 4-minute mile barrier, will become real.