Career Bests
| Event | Time | Date | Competition |
| 50 Free | 20.18 | 2/27/20 | Big Ten Championships |
| 100 Free | 44.26 | 2/29/20 | Big Ten Championships |
| 100 Fly | 47.95 | 2/28/20 | Big Ten Championships |
Career Accolades:
- CSCAA All-American (2020).
- NCAA Championships qualifier in the 200 free relay (2020).
- Scored at the Big Ten Championships in the 100 fly (2020).
- Ranks tied as the fifth-fastest performer in school history in the 100 fly (47.55).
- Member of Penn State’s school-record 200 free relay team (1:17.04).
- Member of Penn State’s second-fastest all-time 800 free relay team (6:24.00).
- Member of Penn State’s third-fastest 200 medley relay team (1:25.35).
- CSCAA Scholar All-America (2020).
2019-20 (Junior Year)
- Awards: CSCAA All-American…CSCAA Scholar All-America.
- NCAA Championships: Qualified for the NCAA Championships 200 free relay...Championships canceled due to COVID-19 pandemic.
- Big Ten Championships (2/26-2/29): Member of the 200 free relay team that broke a school record (1:17.38)...Scored in the 100 fly with a 24th-place finish (47.95) and swam a personal-best in the preliminaries (47.55)...Swam personal bests in the 100 free (44.26) and 50 free (20.18).
- St. Bonaventure (10/4): Won the 50 fly (22.54) and was a member of the winning 200 free relay team (1:24.10).
- West Virginia (10/11): Placed third in the 50 free (21.09) and assisted on the winning 200 medley relay team (1:28.73).
- Ohio State/Virginia Tech (11/1-11/2): Placed second in the 100 fly (48.51)...A member of the first-place 200 medley (1:28.52) and second-place 200 free relay (1:21.20) teams.
- Big Al Invitational (12/6-12/8): Swam personal bests in the 50 free (20.21) and 100 free (44.49) to place eighth and 10th, respectively...Earned career-best time in the 100 fly (48.13)...Member of 400 free relay team that touched third (2:56.25).
- Villanova (1/31): Won the 100 fly (49.12).
- Last Chance Meet (3/7): Set school record in the 200 free relay with an A-cut and school record time of 1:17.04.
2018-19 (Sophomore Year)
- Big Ten Championships (2/27-3/2): Competed in the 50 and 100 frees and 100 fly.
- George Washington (10/12): Had a third-place finish in the 100 free (46.27) and a second place finish in the 100 fly (50.70).
- Big Al Open (11/9-10): Placed third in the 100 fly (49.77).
- Tennessee Invitational (11/29-12/1): Placed third in the 100 fly (48.18) in a personal best time and also earned personal bests in the 50 free (20.48) and 100 free (44.98).
2017-18 (Freshman Year)
- Big Ten Championships (2/21-24): Swam season bests in the 50 free (20.85), 100 free (45.41) and 100 fly (49.50).
- Villanova (2/2): Placed second in the 100 free (46.90) and member of winning 200 medley relay (1:29.76).
High School
- Competed for KP Astromal Akwawit Leszno under coach Marek Grelewicz.
- Won multiple medals at Polish Championships.
- Swam for Poland at the First European Games in Baku 2015 and European Junior Swimming Championships 2016.
Personal
- Full name is Juliusz Gosieniecki.
- Parents are Juliusz Gosieniecki and Magdalena Korzeniowska-Gosieniecka.
- Has a younger sister, Joanna.
- Majoring in nuclear engineering.
- Born July 8, 1998 in Poznan, Wielkopolska, Poland