Workout of the Week: Sub-Threshold Intervals

Generally sub-threshold/sweet spot intensity is valuable as you essentially achieve the same adaptations as you do with threshold work, but are able to do more volume with less overall stress. These sub-threshold intervals develop the foundational mechanisms that allow you to process fuel more efficiently, improve your aerobic capacity and increase muscular endurance.

Incorporating cadence change into these workouts helps you dial in the cadence that is most optimal for your physiology and body type, but also helps you improve neuromuscular efficiency and your ability to efficiently pedal at a wider range of cadence, providing you with more tools for a variety of situations.

Start the workout by finding a hill with a consistent 5-6% grade that you can maintain for about 8 minutes. While performing these sub-threshold intervals, take note how the different gearing makes you feel in terms of breathing and heart rate. How does it make you feel muscularly—do you feel more fatigue? Considering all of these factors, what feels the most sustainable to and efficient for you? Also—which gearing delivered you the farthest up the hill?

The timing of this workout depends on your level of experience and goals, but it would typically be performed in the initial part of the preparatory phase of training, and the time at sub-threshold is increased over time, too. For example, 5 × 10 minutes, then 4 × 12 minutes, then 3-4 × 15 minutes, and 2-3 × 20 minutes, et cetera.

During preparation phase this type of workout can be performed approximately two times per week, but ideally one of the sub-threshold interval workouts is performed on flat terrain to train and improve efficiency at higher cadences, and one is performed on climbs. The number of workouts per week, ultimately depends on your training experience and level of fitness.