Time in Zones: the key to mixing indoor and outdoor training

During the base phase, it is common to quantify training load by time duration per week due to the steady-state and endurance-tempo nature of training. For example, in my last four-week training block the average week was about 12hrs with 50% endurance, 20% tempo, and 30% recovery by power zones. When quantified this way, it is easy to see the training load being applied.

Now as I transition to TB1 HV I can see that in the first week, excluding the ramp test, there are about 6 hours almost exclusively spent in the endurance zone which compares to my average of 6 hours of my 12-hour outdoor week being spent in the endurance zone. This then becomes 9 hours in the second week and so on. As the training stress is applied more spicifically we can see that it takes less total time to accumulate the same TiZ.

This is awesome news for indoor training but it is hidden in information that cannot be extracted simply from total time or TSS. If we can understand our training load in terms of TiZ we can better adapt our training to suit our needs and importantly, our time constraints.

Please feel free to share your thoughts and correct any inaccuracies.