Training time during the period went down 20%. Time at 90%+ HRmax went up 4% to 7%…so well up but still in the polarized zone.
TT time improved 15%. Vo2max improved by >14%. MAP went from 424W to 481W.
Just in a nutshell, 29 4x4 workouts. Estimated 0.5% improvement per workout. Nothing earth shattering there but that load was divided up into two blocks…several days the rider was doing two of these workouts per day.
“Total monthly training volume was reduced in the 2011 preseason compared with the 2010 preseason,”
and
“and 2 HAIT blocks (14 sessions in 9 days and 15 sessions in 10 days) were performed as running.”
Skipping ahead to the conclusion, do you think its accurate to summarize as “off-season cross training delivered increased aerobic capacity and endurance for an (n=1) elite cyclist” or something else?
Maybe! I’m not a cross expert. In this study they basically did either low intensity work or 4x4min @ 90% to 95% of MaxHR. The few times I’ve done cross I’d say my effort level was something different than a 4x4 workout but that doesn’t mean the adaptation would be different. I don’t know enough to say.
But I have done 4x4 several times. The thought of doing 2x/day, 1x/day, 2x/day, 1x/day, 2x/day,… that workout (daily) for a couple of weeks back-to-back makes me cringe a little. I’d have to do some more training before I could handle that training.
if we moved to a cold climate with snow on the ground, I would absolutely cross-train (cross-country ski). So the study doesn’t apply to where I currently live, but can see cross-training benefits in the future.
Oh, I was thinking cyclocross. 
Yeah, I see what you’re saying…he did some running at first and they still saw improvement in cycling performance.
Guess you can definitely say it didn’t hurt in this case. But we can all think of a case where cyclists running (especially @ intensity) DID hurt. 
This was a young guy so keep that in mind. But cross country skiing? I’d totally be down for that.
@bbarrera we should probably always remember ‘Hawthorn effect’ when looking at case study white papers like this…just a note of caution. 
When I recently did my own vo2max block with similar duration intervals, I was surprised that I usually felt up for another session after half a day. I never tried it due to being in work when the desire to be on the bike hit again, and my block was just over a week, not several weeks, but it doesn’t seem completely out of the question for me. 4x4 is a pretty short session, less than 45 minutes, so even though it’s hard, it didn’t create that sort of empty feeling in me.
An increase in Vo2 is an increase in your cardio system so one could get these gains from cycling, running, cross country skiing or something else. I think it is fair to say that for n=1 an increase in Vo2 training lead to an increase in Vo2 without a sacrifice of cycling economy.