Olympic silver medallist Michael Jamieson was also at the British Swimming Heroes event at the Gurnell leisure centre in Ealing.
He told Emma Walden that it was an exciting time to be involved in the sport.
More top news
A lamp in the tower which houses Big Ben is to be switched off for the first time in more than 70 years.
Sir Bruce entertained audiences for more than seven decades.
Work in the tower will also pause over the bank holiday weekend.