Anyone that has heard me speak or trained with a program that I have provided knows that I am not a fan of zeros. It is not that a "zero" in your training log doesn't happen occasionally, but I don't plan for them. The primary reason for this is that a planned zero combined with one or two unplanned zeros during a week can easily derail what goals you have been preparing for. This may seem unusual to some so when I further state that I would NEVER purposely plan to regularly take Monday's off you may ask why? So...from my perspective, here's why - Because if Monday starts the training week, you don't want to start off with a negative. Unless you are a professional athlete and can get in all the training you need in a five or six day period, one full day off at the very start of your training puts undue pressure to complete your plan by Saturday or Sunday. The type "A" person that most competitive triathletes are means that not meeting your goal can make you feel liked a failure.
Often times what will happen then, in order to overcome a poor start at the beginning of the week is that an athlete ends up trying to make up for it with too much volume in a two or three day period. If this pattern is repeated it can develop into an overuse injury. So for me, a planned zero in the training log is something I try to avoid if at all possible. Of course that doesn't mean zeros don't happen, they just aren't planned for.
When building your weekly plan, I have previously recommended using the 3X3 Weekly Training Method. By doing so you will need to consider having a Primary and Additional/Alternate session for each day. The Primary session is the one you NEED to do. It's scheduled for a time (morning or mid-day) when you may have more control over your daily schedule. The Additional session can be done after the Primary is completed and as a second workout that adds to your base fitness and helps accomplish meeting your minimum goal of completing at least three sessions in each sport, three times per week. Hence 3X3.
Endurance fitness is built over time and its main attribute is that workouts build upon previous workouts. If you come from an endurance background in an individual sport you have that much more over those athletes that have no athletic background at all because you most likely have a fitness foundation and understand routines. You know that every workout is not going to feel great. By rotating sessions to ensure that you have a balance between swimming, biking and running, you will also feel the ups and downs of good and not so good workouts. Sometimes it's important to have sessions in the same sport scheduled for back to back days and other times you will need a day in between the individual sport in order to be fresh for the next time you train in that sport. This is often misunderstood when discussing training with single sport athletes. The thought of not running hard with your running group because you have a swim session later in the day or vice versa is foreign to some and requires considerable planning. By planning your schedule with Primary and Alternate/Additional sessions each day you will be able to build upon workouts but also feel recovered so that you can still complete three or more sessions in each sport during the week.
From my experience, it takes about three years of continual and effective training to be able to actually train at higher levels. When a person first starts training in the three sports that make up triathlon they usually make immediate gains because everything they do is more than what they were doing before becoming a triathlete.
Eventually by adding some two-a-day sessions and longer rides and runs the progression continues. Until it doesn't. An athlete reaches a plateau that requires a change in the training schedule. Most often that means training at higher intensity and training longer. In order to fit all of this training into your schedule it is critical to use all seven days in the week to spread load the volume of your effort. If you are doing the minimum nine weekly sessions then skipping one day a week will short you one or two key workouts and will have you performing only 2/3 of the sessions in a particular discipline. If life circumstances take another day from you then you may miss another session and you now will have difficulty completing 1/3 of your sessions in a single sport.
For most triathletes without a swim background, swimming is the first to be dropped from your schedule because it's so time consuming to get to a facility compared to riding or running from your house. Therefore, the typical triathlete tries to get by with one or two sessions a week even though they would never consider doing this with riding or running because those totals would seem dismally low. Following the 3X3 plan is really critical when this happens. Even 30 minutes used effectively at high intensity reaps big benefits in both performance and calorie burn especially in the pool because form deteriorates in a longer session and that is when poor habits start. For bike and run sessions doing two shorter sessions of 30 minutes or so will provide good intensity and is actually better for burning calories than a single 60 minute session because the body is still working harder after two workouts instead of one.
Remember that less is more. If you have less donuts, you can have more donuts! If you can be content with making a plan that doesn't plan for zeros but understand that your log will have some scattered throughout the year due to normal life influences, you will be a better triathlete for it.
Doug Marocco is a 16X Ironman finisher with 9 trips to Kona for the Hawaii Ironman World Championships, but has never participated in the infamous "Underwear Run".