This plan is aimed at boosting an athletes swim economy. By completing work at CSS pace and including weekly pool based strength work, effectively improves neuromuscular co-ordination and power which in turn increases swim economy. The strength resistance sets are based on recent research showing how to efficiently improve swim specific strength, a drag parachute or similar would be ideal but anything that creates drag without affecting technique could be used.
During this 8 week block run and bike training are put into maintenance mode so that the athlete can complete the swim training rested and ready to work hard.
This plan is ideal for the off season when an athlete has time to work on a specific discipline. However IM athletes who are further along into their prep may wish to extend some of the easy bike/run sets.