In Chapter 16 of my book "Running for the Average Joe," I talk about the 7-step training macrocycle, which is further sub-divided into the following individual mesocycles:

* Endurance

* Strengthening

* Tuning

* Peak

* Taper

* Race

* Recovery

While any of the mesocycles provide a certain amount of risk for injury, I'd like to focus on the "Tuning" and "Peak" mesocycles, the stages of the entire training program that leaves us the most vulnerable to breakdown, illness, burnout and injury.

During the Endurance and Strengthening mesocycles, we concentrate on building a "base" that will provide the basics for endurance and durability, but neither focuses on intensity. Because of this, these two mesocycles offer little or no risk to serious or long lasting injuries, if done properly. If minor or nagging injuries do occur, we simply treat them by mild therapy sessions or rest - we normally have time to spare.

When we crank up the intensity in the Tuning and Peak cycles, our propensity for injury or illness increases as our window for treatment and healing decreases. As our upcoming race approaches, our bodies and minds are fatigued, yet this is the time when we want to enter real (shorter) races and training sessions that emulate race mode. This is traumatic and stressful for the body and it weakens the immune system. It's very critical that you listen to your body and take days off as needed. After training for weeks or months for your upcoming race, you shouldn't worry about losing your fitness level for 7 to 14 days.

For more information and training plans, visit "Chapter 16 - Training Plans" in Running for the Average Joe.