Zurich, Switzerland, June 16, 2025: On is thrilled to announce that college track and field sensation Isabella Whittaker (USA) is continuing her journey with the brand, officially partnering with On as she kicks off her professional career after a successful run as an NIL athlete. Making her debut as a professional On athlete at the Bislett Games in Oslo, Norway, on June 13th, Whittaker triumphed in her first ever Diamond League appearance, winning the 400m race in a remarkable 49.58 seconds.
Whittaker doubled down on her Oslo result just two days later on June 15th, at the Diamond League in Stockholm, Sweden – again taking the win in the 400m distance, this time in 49.78 the only runner to break the 50-second barrier in the race. She now has her eyes set on the Diamond League meet in Paris, scheduled for June 20th.
Whittaker, who competed for UPenn before transferring to Arkansas, capped off her illustrious college career in spectacular fashion at the NCAA Indoor Championships in March 2025. There, she was crowned the NCAA Champion in the 400m, clocking an astonishing time of 49.24 seconds. This historic run not only secured the national title but also shattered the American indoor record, made her the second fastest person ever in the discipline, and placed her a mere 0.07 seconds shy of the world record.
“Bella’s talent and drive are undeniable, and her recent performances have solidified her position as one of the most exciting new faces in track and field,” said Kevin Quadrozzi, Athlete Manager at On. Watching her progression over the last competitions made this professional partnership a clear next step. We cannot wait to support Bella on this next step in her career.”
Speaking on this step in her career, Whittaker said: “I’m thrilled to start my professional career with On and excited to have had such a special start in Oslo! I cannot wait to continue to push boundaries, exceed expectations, and achieve big goals for myself and the brand.”
Whittaker had already showcased her elite potential while still in college. In 2024, she earned a place in the Team USA 4x400m relay pool for the Paris Olympics after a strong sixth-place finish in the 400m at the U.S. Olympic Trials and a personal best of 50.17 at the NCAA Outdoor Championships. Her collegiate career is further marked by an impressive eight Ivy League Championship titles.
Whittaker comes from a strong running lineage, with both of her parents having competed in college. Her sister, Juliette, an Olympic 800m finalist, currently runs for Stanford and is also an On NIL athlete.
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