About Masters Swimming (taken from Swim Ireland website)
Masters swimming is generally recognised as competitive swimming for adults who are over 25 years of age, though more and more competitions are open to swimmers aged 19 and over.The focus of Masters swimming is to encourage swimmers to compete against other swimmers of similar age. Competitions are normally run on a heat declared (no finals) basis with swimmers of similar ability (not necessarily of similar age) swimming together in each heat. The final results are then computed on an age group basis. Age groups are 19-24; 25-29; 30- 34; etc. etc. (with 100-104 being the oldest age group for which world records have been set.)
The ability of Masters swimmers varies considerably, from elite swimmers, many of whom were national champions in their youth to lap swimmers who find that competition focuses their training more. The emphasis, as with all swimming, is not on how your competitors are doing but on how you are improving. Whatever your standard there is a place for you
The social side of most Masters competitions is equally important, especially after the swimming, with strong bonds of friendship being formed.