How hard are 6min threshold intervals at 110% FTP

I have just attempted the Red Lake + 8 workout and barely got thru three of the five 6 min intervals at 110% FTP. After the third interval I was seeing stars!
I was well rested beforehand and am doing a Sustained Power Build plan. This is my first power build plan and I have completed approximately 4-5 months of base building. I am pretty fit and have been regularly completing 150km weekend road rides with TrainerRoad workouts during the week.
I would love to hear from others how hard such intervals are. I have the feeling they are no walk in the park.

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Hard, but any vo2 max work is.

Kaiser for example totally crushed me the last time i tried it, that was +120% for 3 mins.

Very rewarding when you manage to complete though

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I love a challenge and will definitely treat with more respect. I think I might build up using shorter intervals before my next assault on that workout.

I did huffaker earlier in the week, I believe it was 6 intervals of three minutes at 110,115,120,120,115,110 and it was super tough. I managed to complete it which gave me a huge sense on accomplishment but I was definitely struggling to complete each one.

Also, as a counterpoint I did Clark on Thursday which was a set of 7 minute intervals at around 95% of ftp. They were very uncomfortable so I can imagine that six minutes at 110 would be grim

Red Lake is a beast and it’s not by accident it’s in the programme to build FTP, which is the hardest thing to do. I wouldn’t worry about completing them all necessarily and instead look for progression week to week. If you need to lower the % slightly to get through them, and need to do that less week to week, that would also be a good sign! Hang in there as the gains will come if you can be consistent.

Depends on the person, some could do this easy orhers would find it brutal. Its going to depend at what % your vo2 max is at compared to your ftp.

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Your conditioning for VO2 max work will improve but regardless working 10% above threshold for more than 2-3 minutes (which is about when it starts to begin really hurting) should be quite challenging.

Customise the workout by either reducing &/or alternating interval intensity or extending rest periods slightly with a view to progressing to it’s ‘unadulterated’ form.

Loud music is essential for me for VO2 max work, change in RPE is very notable for me with tunes on.

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Absolutely agree. I have a play list on my iPhone specifically for tough intervals

If you had been using the 8 minute test to gauge FTP, these 6 minutes would be brutally hard.

Don’t get discouraged by some of these workouts in the build, as I see them as the absolute best case scenario if you can do them and that your FTP setting is probably too low if you finish all of the intervals without a little bit of power drop. I’ve often seen it suggested that if you aren’t punished in the later intervals that you aren’t really getting that VO2 MAX type of effort, but just a hard effort.


Have to say - having only done at worst over-unders so far in a base plan, find it hard to imagine trying to do these. Will get my chance at some stage…

Hopefully base will have done its job by then.

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I always think this when I see a Tabata workout. The original protocol was conducted at something like 200% FTP.

So, yeah, if you’re not dying by the end of doing those puppies (like the Olympic level test subjects were), then 1) it’s probably not VO2, and 2) it’s not Tabata.

I know Tabata isn’t 6 min intervals but the same applies. If you think about it (and I suggest you don’t) VO2 intervals are basically teaching your body how to suffocate/drown. You’re training your mind & body to keep operating whilst intentionally killing it. These are not pretty workouts!

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I know of a chart based on VO2max that suggest 4 x 6 min at 85% of VO2max with 5 min rest. This is for complete exhaustion. Depending on people 85% of VO2max is in the ballpark of 110% ftp. I look forward to try extract a fifth repetition out of my body!

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Think of it like taking your 10 rep max for squat or bench (absolute max, not just working weight) and shooting for 11, several times with brief rest.

You should be getting absolutely stapled :sweat_smile:

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This reminds me of Graeme Obree describing hard intervals as having your head held under water by a bully, but when they let go of your head you keep it there just to hurt yourself more. He’s not really known for being a sensible guy though.

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Innovation/maximal achievement and sensibility rarely go hand-in-hand (his original position is still the fastest around). and VO2 workouts do kind of fly in the face of sensibility.

I’ve often heard that pros aren’t all that much more gifted, it’s just the ability to suffer through so much more pain. This certainly lines up with that…

Breathing is so important on these.

Once you start taking short breaths and start panting, it’s so hard to change back to deep breaths. I find the quicker i’m breathing, the quicker i am to get a stitch, which adds a whole new world of pain to the intervals.
I really don’t like vo2 max work haha

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VO2 Max is work indoors is my nemesis… always really tough. They are particularly difficult for me when I try and do in the evening after a long day.

Music is definitely extremely helpful. It would be really cool if TR users could someone work together to create some custom playlists for some of the more popular VO2 max workouts. It would be even better to have the music kick in hard at the start of each interval. Of course you can do this manually, but these workouts are the one time I wish it was integrated.

We have some nice rolling XC mountain bike trails nearby that have some short and medium length climbs. These also help supplement VO2 max work nicely and provide a little more distraction from the pain.

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What is your cadence like when you do these? I know @chad has mentioned practicing decoupling your breathing pattern from your cadence pattern, i.e. you don’t have to breath fast when you pedal fast.

Just for a reference, and maybe another way to look at it:

1x6min @110% FTP = 12 TSS
1x8min over/under @95/105% FTP = 12 TSS

Basically, the VO2 interval will be 25% more uncomfortable than the Threshold interval.