Question on different phases of training

Some of the basic plans on this site are really just "base".  They get you in a position to finish the distance.  Some of the more specific plans (e.g. Beginner 1/2 IM), actually have their own periodization built into them (prep, base, build, etc.) but assume that when you start them you already have a certain level of fitness base built up.

If you are starting from scratch, using the couch-to plans is a pretty safe way to start building your fitness and get you to the starting line of your race.

In that case the TTB should give you a pretty good idea how to design a program.  Start by picking out your A race(s).  Put these on the calandar as Race week.  Then start working backwards (taper, build, base, etc.).  Usually each block is 3-4 weeks with the last week of the block a "recovery" week.  Then you set up the actual workouts by using the guidelines from the book. 

I'd suggest taking a look at the 1/2 IM plan on this site which follows this type of outline.  Also, you might want to check out Training Plans for Multisport Athletes which has some more plans built on the TTB model.

Donna,

Tudor Bompa who is the father of the periodization principle breaks down your year into macrocycles (can be a year or two years) Mesocycles (months, i.e base, build, speed phases) and Microcycles (week or a few days). By doing this you are letting your body rest and recover when it needs to, build aerobic base to begin the season with a strong foundation, build phases to overtrain and recover, speed work, and a taper phase that will deliver you to the start line of your "A" race uninjured and in peak form. What may seem easy now is laying the foundation for your upcoming season, patience is the key. Overtraining now only leads to burn out and you peaking sometime in March (not good when your "A" race is in June!!). It sounds like you have a great base of fitness already built up so you might want to work on technique during the winter. Good Luck in  your training.