The debate about whether to train through a routine illness, such as a cold, or get out there and "tough it out" comes down to two words: neck test. Let's say you wake up planning to hit the road. As you roll out of bed, you realize something happened overnight and you don't feel so good. The tendency of most dedicated athletes is to stay on task and work out anyway. But that's not always the best choice when it comes to long-term fitness and performance.

Instead of an automatic response ("Let's do it"), think about where you feel bad. If it's above the neck (stuffy nose, headache), then you're probably good to go. Take it a little easy -- obviously you're not 100% -- but you don't need complete rest. Above the neck means you're above the "gotta rest" cutoff line.

The main exception to the neck test is if you're feverish. You really won't feel like riding and it's smart not to. A fever indicates infection. Don't mess with that. If the problem is in your throat, chest or stomach, take some time off. Pushing through a workout could make you sicker and prolong the illness. Rest now to limit downtime, then ease back into exercise when the symptoms subside. Pushing too hard too soon could cause a relapse.

Remember, 2-3 days off won't have much, if any, negative effect on your fitness or performance. But if you try to push through sickness, not only are you somewhat wasting time with sub-par workouts, you're risking the chance of a brief illness lasting a week or more. Then you will see diminished fitness.