My training program has two main purposes.
Train hard to achieve the highest level of race specific fitness.
Show up to the start line ready, rested, and injury free.
Although the bulk of the year is made up of purpose #1, #2 is just as important. Overtraining can be detrimental to an athlete as it can put them at risk for injury, stress fractures, burnout etc. Tapering maximizes race performance by eliminating the pre-fatigue that limits performance in everyday workouts.
About 2 weeks out from an Ironman I begin my "Taper." This past weekend marked the official start of my 2 week taper! Hallelujah! Weekend volume decreased from 5.5 hour bike rides and 18 mile runs to a 3 hour ride and 11 mile run. Volume will continue to decrease through this week about 50% and will decrease just slightly in workout intensity. The week of the race will be more about keeping the legs moving, nutrition and hydration (and hopefully staying calm!).
As I continue to stay active, it is also important for me to maintain hydration and fueling with good foods to assist in muscle recovery as my body rebuilds itself after my final, hard training block. I built up a lot of fatigue in my muscles and they need 2 weeks to rebuild and recharge so that when I hit the start line I'm primed and ready to go like a rubber band!
Not convinced on the importance of the Taper? Check this study out for more info on different tapering strategies!