Klæbo and Potetmannen98 Swore by Beetroot Juice – Expert Says It Boosts O₂ Uptake

Johannes Høsflot Klæbo, one of the world’s best cross-country skiers, once consumed large amounts of beetroot juice in an effort to improve his oxygen uptake (O₂ uptake). Although he describes the taste as “gruesome” and notes that it can cause red discoloration of stools, he maintained the routine for years due to its alleged performance benefits. The idea behind the regimen was that the high nitrate content in beetroot juice helps dilate blood vessels, thereby increasing blood flow to active muscles.

Doctoral candidate Kristin Lundanes Jonvik, who began investigating the effects of beetroot juice on sports performance, explains that many athletes use it without fully understanding why it works. According to her research, the benefit, though small, can help delay the accumulation of lactic acid. She notes that the improvement is most significant for less-trained individuals, though even elite athletes like Klæbo have incorporated it into their routines.

In addition to Klæbo, 26-year-old Ibrahim Azam—known on TikTok as Potetmannen98—endorses the drink. Having overcome significant weight issues and burnout through a combination of surgery, a healthier diet, and regular exercise, Azam credits a daily sip of beetroot juice for improving his breathing and endurance. Despite its unpleasant taste and potential side effects such as red urine, his personal experience and growing consumer interest, as evidenced by increased sales from major grocery chains, suggest that beetroot juice remains a popular supplement among athletes.

Overall, while the effect of beetroot juice on performance is modest and highly individual, both elite and amateur athletes continue to experiment with it as a potential edge in sports requiring high aerobic capacity.