Hertsmere Flyers member Joshua Foreman set a series of personal bests at the East Region Bagcat Championships.
The 11-year-old travelled to Norwich to compete in his preferred stroke over his favourite distances.
Foreman smashed his personal best by nearly 16 seconds in the 200m backstroke heat for fourth spot.
He also knocked more than seven seconds off his 100m backstroke personal best as he again finished fourth in the heat.
In the 100m final, the Hertsmere Flyer came fourth as he knocked just over a second of his PB.
In the 200m final, Foreman finished sixth as he again set a new PB by more than a second.
Foreman has been with Hertsmere Flyers for three years and goes to Yavneh College in Borehamwood.