New one from Rønnestad ... 12 weeks of SST in elite XC skiers

high level summary: you become good at what you train

First of all one caveat: many drop outs in the HF group. This renders all statistics impossible for this group, hence, we can’t say a lot about frequency of these sessions.

Intensity was 85% Hfmax. They say Zone 3 in a 5 zone model. Seiler’s 4x16 were at ~88% HFmax in non-elite cyclists.

LF group did two SST sessions per week- Plus one Zone 4/5 session (but not more information given on these)

  • 30min TT improved
  • %vo2max at 4mmol improved
  • exercise economy improved
  • vo2max did not improve (so one [potential] session/week is not sufficient to push somethin here)

It is interesting to me that they speak of high intensity intervals. It is a pity that the HF group had so many dropouts, would have been interesting to see, what the minimum effective dose per session is. However, at SST in this population you really have to accumulate enough time in one single session. Otherwise the stimulus is to low. But this is just my speculation.

Since one “real” HIT session/week seems too little in this population it begs the question if a focused approach is the way forward. Adding another HIT session to the current regime would probably be too much load. Hence, push and pull may be a sensible approach.


Thanks for sharing, just reading one of the intro paragraphs and a bit confused by the below:

The optimal interval duration for well-trained endurance athletes appears to be 4–10 min, with a beneficial effect observed at a total effective duration of approximately 15 min. However, durations of 30–45 min appear to elicit the best effect

Is he saying 4-10 is good, even out to 15, however 30-45 seems best?

no, 4-10 refers to a single interval, 15 and 30-45 refer to total work time

What are the physiological differences in Oxygen utilization (and therefore VO2) between cross country skiers and cyclists? It seems like XC people use way more muscles than cyclists. Does that affect how VO2 and other measures of performance are realized between the two?

I have a feeling that comparing XC to cyclist is not quite as predictive across the two as we may think. Just a hunch. Meaning what XC athletes might be doing may not be as relevant to us as many people assume. Or (and this is most likely) I’m wrong and they are very closed related.

Still. I’m not sure we can take what XC freaks are doing and applying it to our easier level of athletics.

This was interesting, thanks for posting. I guess in XC-skiing they rarely go for the longer 20-30min intervals such as in cycling, but I wonder if there would be an additional benefit in doing so?