Long-distance triathlon glossary·2xLT2

Double threshold training

Load

Protocol scheduling two lactate-threshold sessions on the same day to maximise adaptation.

The double-threshold protocol, popularised by Norwegian coach Marius Bakken and later used by Jakob Ingebrigtsen, consists of two sessions around the lactate threshold (LT2) on the same day, separated by a few hours of rest. The aim: activate lactate transporters (MCT1/4) twice to force a superior lactate clearance adaptation compared to a single equivalent session. In long-distance triathlon, this protocol is mainly applied in running during Build and Peak phases.

In TriPaced:

In TriPaced, double-threshold appears in advanced Build and Peak plans when weekly volume exceeds 10-12 h. It is shown in the session card as 'complementary LT2 session' and is only prescribed when morning recovery is satisfactory (HRV and resting HR within limits).

Source Mujika et al., 2023: The return of the double-threshold training concept in elite middle-distance running, IJSPP

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