5 minute efforts are a critical effort level for speed in Cross Country as well as for having the extra kick of effort at the end of those longer Marathon events. Building up you 5 minute efforts will give you more capacity to train the specifics later in the season. To execute this plan, follow the threshold based targets for all the workouts except the 5 minute workouts.
For the 5 minute workouts
Week 1: Use the % threshold target and range as a guideline to help you pace yourself. But focus on maximizing your average power for the intervals, see how high an average you can do each time. Of the 3 intervals, take the middle effort in terms of average power, and use that for you target for the workouts next week.
Week 2: Taking your middle interval in terms of average power as a target, complete all three intervals with the goal of all of the them having an average power above the target.
Week 3: If you were able to successfully match the target from the week before, increase your target by 10 more watts for this week. If not, keep the target the same.
Week 4: This week will be a rest week. Focus on keeping the effort levels within the ranges and getting some recovery time. There will be no 5 minute efforts this week.
Week 5-8: Take your power target from week 3 and use it for week 5. Each week, if you were able to hit the target the week before, increase the target by 10 watts and keep all 5 intervals above that target.
I provide coaching for all levels of endurance cyclists. I specialize in Off-Road training with extensive experience racing at a professional level in both XCO and CX. I want to help you reach your goals and I know that the key to this is targeted purposeful workouts, and engagement. I take care of the numbers, you focus on giving it 100% towards you goals.