Puck Pieterse was born on May 13, 2002, in Amersfoort, in the Dutch province of Utrecht. From a young age, she spent many hours on her cyclo-cross bike, earning a reputation as a major talent. She reinforced this by becoming both the Dutch and European junior cyclo-cross champion in 2019, and in 2020, she also claimed the European title in the U23 category.
A year later, Pieterse broke through immediately at the professional level as a rider for Plantur Pura. In the 2021/2022 winter season, she consistently rode among the top women at the highest level, crowning her performance with a U23 world title in Fayetteville, USA. In the 2022/2023 cyclo-cross season, she showed further improvement: in addition to winning the European Championship in the U23 category, she also claimed World Cup victories in Overijse, Hulst, Val di Sole and Besançon, and became the Dutch national champion among the pros.
Pieterse is a world-class competitor not only in cyclo-cross. In 2023, she decided to focus on mountain biking with an eye toward the 2024 Olympics in Paris. She quickly rose to the top of this discipline as well, winning World Cup races in Leogang, Nove Mesto, Val di Sole and Les Portes du Soleil, and securing the overall World Cup title. She also became European champion and won silver at the World Championships in Glasgow. Early in 2023, she made her road racing debut in the gravel race Strade Bianche, where she impressively finished fifth among the world's top riders.