Challenge Bike Workout #3: Descending Intervals

In this week’s Challenge bike session, cycling coach and expert Matt Bottrill really turns the screws with some descending intervals at high intensity.

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This 90-minute session from bike coach Matt Bottrill is the third in our series of four cycling workouts that are designed to lead you to your best 40K time trial, which will be one part of the virtual Olympic distance “triathlon” challenge (a 15-minute strength circuit, 40K ride, 10K run) at the end of the month. 

Bottrill is a world-renowned bike guru, cyclist, and coach who works with pro triathletes such as Tim O’Donnell, Tim Don, Matt Hanson, and Justin Metzler. He also works with the Lotto-Soudal pro cycling team as time trial bike fitter and planner. 

Throughout these workouts, Bottrill uses Levels 1 through 7 (listed as L1, L2, etc.) to determine effort or RPE. If you prefer to train by power or heart-rate then he has those listed too. See below (beneath the workout) for a full explanation of levels and their respective heart-rates and wattages. 

This third workout is, by Bottrill’s own admission “a tough one,” so be prepared to work hard and pedal well. He said: “This session is going to be really tough mentally, so you need to go to that special place of wanting to suffer to get the rewards that will come from this type of training.”

Bottrill advises always using the cadence that gives you the best power transfer, as well as staying in the aero position for all of the Level 5 efforts.

The good news is that the intervals get shorter as you progress through the workout—from four minutes down to one minute at maximal effort—and then you’ll wrap it up with a 15-minute high cadence recovery cooldown. 

Triathlete Challenge: At Home Bike Workout #3


15 min. @ L1, high cadence 90-100+ RPM 

Main Set

Do in aero position using cadence that gives best power transfer

4 x 4 min. @ L5 with 4 min. @ L1/2 recovery between each

3 x 3 min. @ L5 with 3 min. @ L1/2 recovery between each

2 x 2 min. @ L5 with 2 min. @ L1/2 recovery between each

1 x 1 min. Maximal effort


15 min. high cadence recovery

Explanation of Exertion Levels

1 ACTIVE RECOVERY (VERY LIGHT ACTIVITY)  Hardly any exertion, but more than sitting down < 55% <68%
2 ENDURANCE (LIGHT ACTIVITY) Feels like you can maintain for hours. Easy to breath and carry conversation  56-75% 69-83%
3 TEMPO (MODERATE)  Breathing more heavily. Still somewhat comfortable but slightly challenging  76-90% 84-94%
4 LACTATE THRESHOLD (FTP, Functional Threshold Power)  Breathing more heavily. Still somewhat comfortable but notably more challenging 91-105% 95-105%
5 VO2 MAX (VIGOROUS)  Borderline uncomfortable. Short of breath, can speak but not sentence   106-120% >106%
6 ANAEROBIC CAPACITY (VERY HARD ACTIVITY)  Very difficult to maintain exercise intensity, can barely breath and can only speak a few words   121-150% N/A
7 NEUROMUSCULAR POWER (MAXIMUM EFFORT)  Feels almost impossible to keep going. Completely out of breath. Unable to talk  N/A N/A

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