Quick Profile: Flying 40s

Flying 40s is a high-intensity, short-duration, lower-cadence interval profile with an aim to increase muscular strength and power output. This drill is also known as “40/20s.” The concept is quite simple: work in Zone 5 (very hard) for 40 seconds, rest in Zone 1 (easy) for 20 seconds, repeat 10 times for a 10-minute set. The amount of recovery offered after each repetition does not allow for full recovery, making your riders work through lactate buildup. The repetitive efforts will improve lactate tolerance and also target VO2 max improvement. But you need sufficient recovery in between sets, and knowing how much at this intensity is too much is essential to not overdoing a good thing so that your riders can achieve the goals of the workout. 

I am not usually a fan of repeated, short intervals except when the intervals are very purposeful, as is the case with Flying 40s. These efforts are fun (to the extent that pushing this hard is “fun”!) and they fit nicely into a well-rounded cycling program. The intensity target for this profile is power Zone 5, the zone above lactate threshold, but you can also coach using a perceived exertion of very hard (but not very, very hard or maximal). This profile will guide you in explaining the physical sensations your riders should experience in order to achieve the desired adaptations. 


  1. This is great ! I’ve had a flying 40’s profile for almost 2 years now, (after seeing it in an article by Selene Yeager in Bicycling Magazine)

    In fact it was my profile for this morning’s class !

    Try it out folks ????

    1. Author

      Hi Joe! Yes, I saw it in the same magazine and created my first Flying 40’s profile about two years ago as well. When I realized that a version didn’t exist on ICA, I decided it was time to add it to the collection. It is such a fun ride, and the time goes by so quickly! Glad you’re using a version for your riders too 🙂

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