For decades, experts thought running 42.2 kilometers in under two hours was impossible. But now, two athletes have done it in official competition, proving that the barrier can be broken.

In April, Kenya’s Sabastian Sawe and Ethiopia’s Yomif Kejelcha both broke the two-hour marathon barrier at the 2026 London Marathon, finishing in 1:59:30 and 1:59:41. This historic moment shows that human limits in endurance sports may be higher than once believed.

Scientists explain that such speed comes from a mix of training, genetics, and technology. Modern shoes reduce energy loss, while nutrition and pacing strategies help runners maintain high speed. Studies suggest that the human body’s oxygen use and muscle efficiency may allow even faster times in the future.

This raises questions about the true limits of human performance. Researchers believe marathon times could be reduced by a few more seconds than the current record. They have also studied other extremes, saying humans could hold their breath for over 11 minutes and lift more than 500 kilograms in strongman contests. They may even sprint at over 44 kilometers per hour, breaking Usain Bolt’s speed record in 2009.

The marathon breakthrough shows how science, training, and determination can push boundaries once thought unbreakable. Human limits are flexible, and future athletes may go even faster.