Math, for some of us, isn't our strong suit… especially when you are trying to compute specific training zones on the fly using Lactic/Anaerobic Thresholds (LT/AT) or Functional Threshold Power (FTP)
MTB coach Curt Wilhelm has created two easy to use, online tools you can find here.
Coach Linda Wallenfels has a similar tool here.
And for you data junkies, Cycling Power Models has a very comprehensive tool that is sure to satisfy you for years.
A word of caution
The computer world has a saying; “garbage in = garbage out” which describes how using inaccurate (garbage) data to compute with can only lead to inaccurate (more garbage) results. The calculators above are designed for endurance athletes who have achieved a level of fitness and learned to tolerate the pain/discomfort of working at or above LT/AT or LT2 (upper Threshold) for extended periods of time.
In this three part series from last year; Is a 20 Minute Threshold Field Test realistic for your class? I discussed multiple reasons why I question using 20 minute field tests to determine Threshold Heart Rates for the “typical” student in your class. If you haven't read them I'd encourage you to do so now. My biggest issue with 20 minute field tests is that many of the Club Athletes in our classes haven't learned or developed the pain tolerance needed to sustain the Threshold level of intensity necessary to find an accurate average HR… but instead find some number below Threshold = “garbage in” 🙁
if you feel you have a good understanding of your AT/LT/LT2 I'd like you to try one of the calculator above. Then consider what will happen if instead of entering a true Threshold HR, you use a HR 5%-8% below it.
Can you see how “garbage in” could have some students under training?
In case you are wondering, I see using HR training zones based on LT1 (Aerobic Threshold) as much more accurate for Club Athletes, especially when combined with the simplified Two Threshold – Three Zone system advocated by ACE – The American Council on Exercise.
Do you have video in your studio? Here are two great videos for running a 20 minute field test for FTP or threshold Heart Rate.
John is a member on the AFS (Association of Fitness Studios) Advisory Council.
Holding certifications from; Schwinn, Heart Zones, Team ICG and Life Time Fitness, John's held regularly scheduled cycling classes between 1998 and 2015 when he moved to Florida.
When the weather permits, you'll find him riding and leading outdoor groups by himself or with his Tandem partner (wife) Amy.