Next time you are doing a swim workout and you are losing interest.  Do some RELAYS.  Find some friends or teammates or just some other people at the pool.  Depending on the ability levels and ages of the participants, do some 25, 50 or 100 yard relays.  Have everyone swim their leg as fast as they can and then give them a rest interval of at least 1 to 1.  So if it takes the swimmer 1 minute to swim a 25 have then rest at least 1 minute before they take their next turn.  For faster swimmers, have them swim more often or shorten their interval.  These workouts are high energy and FUN.  Try one out at your next workout and let me know how it went.  Happy Training!!