This plan was designed by Joe Friel using the principles of The Triathletes Training Bible for the OVER-age-50 athlete. The major difference between this and the under-50 plan is that brief rest periods are built in more frequently for over 50.
This plan is best started about 23 weeks prior to your first A race of the season. This plan is quite detailed, often including alternative workouts, yet easy to follow.
To start this plan you should be able to swim 1 hour, bike 1.5 hours, and run 1 hour. Over 12 weeks you will increase your weekly volume from about 9.5 hours to 14 hours including 3 swims, 2 to 4 bikes, 3 to 4 runs, and 1 to 2 strength workouts each week. The exceptions are the R&R weeks every third week with volume significantly reduced for 4 to 5 days and self-testing at the end of the week to measure progress.
The plan uses common tri language to describe the workouts and is easy to follow. By the end of 12 weeks you will have excellent Base fitness and be ready to start the Build period 11 weeks prior to your A-priority, half-Ironman race.
(For detailed description of how to set your zones for heart rate, power or pace go to http://tinyurl.com/29t3q6m and click on USING HR, POWER AND PACE (PDF) under my picture.)