Cast for two

Monday, May 19, 2014

Setting Strava heart rate zones based on Lactate threshold heart rate

Recently, i got my lactate threshold heart rate (LTHR) tested in a lab by taking blood samples. The threshold measured this year was 175 beats per minute. I wanted to customize my zones in Strava pro based on this threshold. I googled around but did not find clear information how to determine the zones based on LTHR. So I did a bit of research. In Joe Friel's book "The cyclist trainings bible" at page 37 Table 4.5, the following zone's in function of the lactate threshold heart rate (LTHR) are defined as following: 
  • Z1 Recovery 65% - 81% 
  • Z2 Aerobic 82% -88%
  • Z3 Tempo 89% - 93%
  • Z4 Subtreshold 94% - 100%
  • Z5 Suptheshold 100% - 102%
  • Z6 Anaerobic > 102%

In the book of Hunter Allen and Andrew Coggan, "Training and racing with a power meter", on page 83 Table 3.1, the zones are defined by Dr. A. Coggan as follows in function of the Functional Threshold Heart Rate (FTHR) : 
  • Active recovery < 68% of FTHR
  • Endurance 69% - 83% of FTHR
  • Tempo 84% - 94% of FTHR
  • Lactate threshold 95%-105% of FTHR
  • VO2 Max >106% of FTHR
  • Anaerobic Capacity N/A
  • Neuromuscular N/A

See also the explanation on youtube: Getting started with power training or here Training Zones Explained
I think those zones map better to those defined by Strava. Strava has no zone for "Active recovery". Endurance is called Moderate in the Strava zones. I would also collapse the "VO2max", Anaerobic en neuromuscular" into the Strava "Anaerobic" zone. These are basically the zones that earn you points in the red.
So based on your cycling Lactate Threshold Heart Rate (LTHR) or FTHR set zones in Strava as follows:
  • Endurance : < 68% of LTHR
  • Moderate: 69% - 83% of LTHR
  • Tempo: 84% - 94% of LTHR
  • Threshold: 95%-105% of LTHR
  • Anaerobic: > 106% of LTHR
I my particular case of hitting the lactate threshold (LT) at 175 beats per minute this boils down to:
  • Z1 Endurance: < 119 bpm
  • Z2 Moderate: 120 - 146 bpm
  • Z3 Tempo: 147 - 165 bpm
  • Z4 Threshold: 166 - 184 bpm
  • Z5 Anaerobic: > 185 bpm