Long-distance triathlon glossary·Z5

Zone 5 : VO2max / Maximal aerobic speed

Load

Very intense effort zone (106-120% FTP or 3-6 min maximal effort) targeting VO2max and pushing the cardiorespiratory system to its limit.

Zone 5 pushes the cardiorespiratory system to its limit, targeting VO2max : the maximal oxygen uptake. In cycling, this corresponds to 106-120% of FTP (maximal intervals of 3-6 minutes). In running, it is around 5K race pace. These sessions develop the aerobic engine deeply, but require full recovery (48-72h) and should not be done too frequently : once per week in the BUILD phase is typically sufficient.

In TriPaced:

In TriPaced, Zone 5 sessions (e.g. 5×3 min at maximal effort, 3 min recovery) only appear in BUILD and PEAK phases for ADVANCED profiles. For BEGINNER and INTERMEDIATE profiles, Zone 4 volume takes priority. The plan never stacks Zone 5 and Zone 4 on the same day.

Related terms

  • TSS : Training Stress Score
  • CTL : Chronic Training Load (fitness)
  • ATL : Acute Training Load (fatigue)
  • TSB : Training Stress Balance (freshness)
  • Sweet spot : the efficiency zone
  • Threshold : the upper sustainable limit