Nikoletta Vlahopoulos got her start in gymnastics at the age of six as she was super active and naturally flexible, so her parents decided to put her in gymnastics. Nikoletta took to the sport right away and began competing in November 2017 as an Xcel Bronze with Riverview Gymnastics. At her first meet, Turkey Tumble, Nikoletta won the bars, beam, floor, and all around titles. Nikoletta had a great season as an Xcel Bronze and finished her season at the Shoot for the Stars Invitational where she came in first on beam.

Following her 2017-2018 Xcel Bronze Season, Nikoletta began training at US Gymnastics Develop Center II. Nikoletta began competing as a level 3 in October 2018. At her first meet, the Pumpkin cup, Nikoletta won the bars title and came in fifth on floor and in the all around. In February 2019 at the New Jersey State Championships, Nikoletta won the floor title and came in second on beam.

As a level 4 during the 2019-2020 season, Nikoletta began her season at the Princess Invitational where she finished second on beam and floor as well as third in the all around. Throughout the remainder of the season, Nikoletta finished in the top two in the all around at each of her meets. Nikoletta concluded her level 4 season at the New Jersey State Championships where she won the beam, floor, and all around titles as well as a silver medal on bars.

Nikoletta tested out of level 5 in January 2021 at the Mahwah Season Opener where she won the vault, bars, floor, and all around titles. Nikoletta competed her first meet as a level 7 at the Heart 2 Heart Classic in February. Here, Nikoletta won the beam title and finishes second on vault, bars, floor, and in the all around. In April at the New Jersey State Championships, Nikoletta won the bars title with a 9.750 and came in sixth all around.

After her 2021 level 7 season, Nikoletta began training at ENA Paramus. Nikoletta began her level 8 season at Christmas on the Chesapeake where she won the bars, beam, and all around titles.

Currently, Nikoletta trains 27 hours per week under coach Craig Zappa at ENA Paramus Gymnastics. In the near future, Nikoletta's goal is to qualify Hopes. In the future, Nikoletta hopes to qualify elite and represent her country of Greece.