Science behind Sweet Spot Methodology


In an effort to tease out what makes “88%-92%” so special, I have a question if anyone is willing to indulge.

For those folks who have a fair bit of experience with sweet spot interval training (be it TR SSB, etc or not), do you find that you regularly/semi-regularly need to either drop the intensity or proactively modify down to an endurance IF?

Does anyone use something like 84%-whatever as their range? (single percentages within the range I believe is splitting hairs…however, it doesn’t seem that working this much lower day over day is “trivial” or “splitting hairs”)



What makes it special is that I can do sweet spot work day after day, building muscular endurance, without much need for recovery. It takes 5 days in a row without a recovery day before my legs to start feeling the need for a recovery day.

Good training effect without need for frequent recovery is what makes it “sweet spot.”


p.s. prior to TR my outside SS work had too high low intervals - I refused to drop down to 100 watts after a 220 watt interval. And so the outside SS work was too hard. Upon joining TR last year, erg mode forced the rest intervals to be easy. That made all the difference for me.


It depends on the duration. I did have a bit of trouble with eclipse but i was coming bsck from a cold and a week vacation. I did get two rides in during that vacation but they were both .6 type group rides of one and two hours.

I feel like i could do 5 hours of rides which focused on 85-90% intervals. I don’t really get sore, just fatigued. Sore is when it hurts to walk downstairs and on flat ground. Fatigue it is only hard going up stairs. Throw in a day of
.65ish work and I’m ready to go again.

That’s why the tr plans work for me, i am recovering between efforts. There are so many ways to skin a cat there really is no right and wrong ways but one’s that are better suited to your available time and lifestyle.


This is exactly what I have been doing so far this year, and so far the results are starting to look pretty good. There is an excellent WKO4 webinar on Youtube which demonstrates this. I don’t think I have that much more room to grow my FTP upwards as I am sticking pretty constant at around 4.5 w/kg and am in my mid forties, but I am definitely starting to push out the length of time I can hold that power by progressing the interval length rather than the intensity.


This brings up an important point — how do we know we’ve reached our max potential and when we do, if the grand purpose of SS work is to raise FTP but we can’t raise it any more, should we switch to a different training methodology?


The grand purpose of training is to improve the abilities you want to see improve. If you stop seeing improvement - over a reasonable period of time - change the stimuli. When the same happens with that, change it again.

Training and improvements for endurance sports take place over a multi year timescale and one of the reasons I think looking at, as a lot of training studies do, improvements in a 4/6/8 week block of particular methodology is fraught with difficulty. We have no real idea the background or training trajectory of the study subjects. Often the simple fact of following a plan supersedes what the plan actually is.

An Olympian following a four year training cycle or a Grand Tour contender are still trying to eek out those extra tiny percentages so for the rest of us there is always some improvement to be had by changing things up - even if by dint of age that ‘improvement’ is actually standing still and delaying the effects of ageing.


I’m starting my fourth season, and still seeing 4-6% ftp bumps when starting sweet spot work. But my ftp falls after taking time off.

From the beginning of my training I have worked on progressed the length of intervals, to enjoy longer climbs. That has worked well for me too. I’ll checkout the WKO video, thanks for sharing.


Yeah, me too. Not sore, but fatigue. So I tried a SS -> Tempo -> Endurance progression (from Frank Overton’s blog post), and that definitely helped. It often ends up being SS --> Endurance --> Petit…typing in Petit into the workouts search box is usually my cue to back off for a day or two.

I guess it makes me wonder if routinely lowering the intensity a shade (84% ish) would be much of a penalty from a “best bang for you buck” metabolically. 84% -> 84% -> Endurance I could probably live with.

(sidenote: my FTP estimate is solid. I can hold my FTP for about 45 mins (from time to time) but that’s because I can’t pace myself out of a paper bag…I have always looked at it from a benchmark for fitness changes perspective, not literal hour power. Also, workouts of various types feel and have HR profiles that are “correct”)

Great question. I started riding seriously 3 yrs ago so I think (despite my age, 45) that I have plenty of room for FTP growth in the next few years. Having said that, I hear what your saying @Captain_Doughnutman. November is the time to be thinking about this stuff. I don’t want to be second guessing my training in February.


At approximately 1:12:14 of the video, he says “I would go ten and extend to tempo”…

Would anyone be able to translate that for me? What’s he mean there?


I think he said “I would do TAN and extended tempo” which was one of the bullets on the screen as he was talking.


Yes of course. Thank you! :smile:


Beyond the science, yesterday I did a 35 minute climb for the 3rd time. Previous efforts were last summer with 11% higher ftp and 10lbs lighter. This was my best paced effort, climbed all the way slightly above ftp (average) without feeling the need to stop and catch my breath. Without the stops I was 3 seconds off PR despite extra 10lbs and down 35W on ftp. Really enjoy how it feels to climb once I’ve got a couple weeks of sweet spot work completed.


Cool. A block of sweet spot oriented training can get you up those sustained hills faster.

So do you plan to continue to do sweet spot intervals year round or as base? (Not sure what phase of training you’re in.) Do you also do long aerobic rides? Aerobic threshold intervals or rides? Or (gasp!) tempo zone rides?

Once you achieve this training affect with this sub threshold interval, what comes next? Rinse and repeat?

These are somewhat rhetorical questions as I’m trying to get at some of the upsides of a “theshold training” orthodox, of which sweet spot is core.


I have a ~1km/~3-4% hill on my daily commute (each way), I use it as a general litmus of my fitness (I just ride it easy, no hammerfest). I just completed the SSB1+2 block and the most notable change from Day 1 to now is the absence of heavy breathing when going up those hills. It’s nice to know all that work accomplished something!


Not sure what my goal is for this season, thinking about the California Triple Crown jersey, or improving my climbing and/or TT. I like being outside and doing 3-6 hour rides at least twice a month. I’ve already put down a short traditional base, now SSB-HV, and then probably general build with substitutions on the weekend (long outside rides). More than anything I need to get serious about getting weight down.


Six weeks of a polarised training-intensity distribution leads to greater physiological and performance adaptations than a threshold model in trained cyclists

japplphysiol.00652.2012.pdf (798.2 KB)


That study design doesn’t even follow what others have said is what one is supposed to do when doing polarized plan. As mentioned in the other thread, most athletes spend less than 10% of their time doing intensity using the polarized approach during the bulk of their time. 20% of sessions works out to be less than that in time. They only go above 10% during the late peaking phase.

So we’re comparing a late cycle prep to an early cycle prep. Not exactly apples to apples.


This study has definitely been discussed on the forum several times. The problem is that the threshold plan in this study doesn’t really replicate the TR plans–which most also include significant time in Zone 3.


Ok sorry to post duplicates then.

I wasn’t really referencing this to compare specifically to TR plans, as there are many different ones. It was in direct response to the OP question on science behind Sweet Spot, which in that study is referenced “45% of training time… [consisted of] …THR sessions included 60min at a power output half-way between the LT and the LTP (i.e. in zone 2)”. which I think is basically sweet spot.

I agree "The aim for THR was to achieve 55% of training time in zone 1 and 45% of training time in zone 2, with no zone 3 training time.
Without doing the math, it doesn’t look like the TR SSB LV plan has 55% in zone 1 and as you pointed out it does have some zone 3 in SSB LV II, for example.