I’d suggest to going back to the type of training you were doing right before you did your taper. You can get 2-3 weeks of more base training and intensity followed by 1-2 weeks of taper into the race. You’ve probably been tapering so feeling very good. This could be a good opportunity to lay down one bug volume week now, then a 10-14 days with more of a focus on intensity before tapering.

Scott

When you add intensity be sure you do not have to drop the volume more than 3-5% in a given training block. In other words; add intensity don’t substitute it for base aerobic work. Zone 3 work is normally added either as continuous efforts of 20-60 minutes or in interval method doing long repetitions of 10-20 min. With your 2-3 minute reps you’ll need to do quite a fe of them to get the volume up to 20-30 minutes in a session which would be a good amount for a typical 50km training plan. I do not recommend you bump your training volume in this period. Stick with the intensity volume you’ve become accustomed to recently. Adding too much now will drive you down into fatigue too much. We normally recommend building to about 1 hours of Z3 per week before starting to substitute Z4 for some of the Z3 work.

Scott