The Marlins swimmer first went under the record in the morning heats, clocking 54.65, taking two hundredths of a second off Smith’s 23-year-old time of 54.87.
She then lowered that time by another three hundredths of a second to 54.34 to claim gold and the national title.
Less than 20 minutes later McSharry added her fourth gold medal of the meet in the 100m breaststroke where she touched in 1:07.91.
UCD’s Andrew Moore, Erin Riordan, Kate Kavanagh and Kevin McGlade broke the third relay record of the week as the quartet touched in 1:35.74 in the mixed 200m freestyle relay to break their own record (1:36.87) set at the Leinster Championships in November.
National Centre Dublin’s Jordan Sloan, Robbie Powell and David Prendergast took a clean sweep of medals in the men’s 100m freestyle final. Irish record holder Sloan touched first in 48.93 followed by Powell (49.22) and Prendergast (49.26).
The men from the National Centre in Limerick followed this claiming gold, silver and bronze in the 100m breaststroke through Eoin Corby (1:01.04), Liam Doyle (1:01.26) and Uisean Cooke (1:01.79).
National Centre Limerick swimmers continued to impress as Cillian Melly (4:17.82) and Cadan McCarthy (4:20.71) took the top spots in the 400m individual medley.
In the women’s event, Jessica Burke of NAC SC clocked 5:00.25 for gold ahead of Leander’s Emma Henderson (5:05.43) and Dolphin’s Hannah O’Shea (5:07.15).
Emma Reid retained the 50m butterfly title for the third time in as many years, touching ahead of sister Rebecca (27.82), in 27.04. The bronze medal was shared by Otter SC team-mates Jena Macdougald and Cara Stapleton who finished in 28.36.
UCD’s John Higgins claimed a first national title, winning the men’s event in 24.06.
Ards’ Amelia Kane cruised to victory in the women’s 1,500m freestyle final. The 15-year-old touched in 17:02.30 adding to Wednesday’s 200m butterfly gold medal.
Competition continues today and tomorrow.
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