Keeping a Biking Log
All logs in your triathlon training are meant to help you keep track of your progress and to help you identify aspects of your program that need improving. Good log keeping includes more than simply entering data. It is very useful to include information about the weather and other external factors (a cold perhaps, or an injury). Your log should also include notes about how you felt during each workout.
Your bike computer will provide the raw data. You should make the extra notes. If, for example, you frequently note that a beginner-type workout was very hard for you, it might be because you are doing too many hard workouts. Ease up for a week in all three sports to see if that makes a difference.
Keeping a biking log will also help you keep from overdoing your training. You should be riding no more than sixty miles a week. That's three respectable rides, more than enough for your triathlon training.
Perceived effort is a phrase often used in sports training to indicate how hard a session felt. You can quantify this using what is known as the Borg Scale, which originally ran from zero to twenty-one, later revised to range from six to twenty. Six indicates no effort, eleven is a light level of exertion, and twenty is maximal effort.