Normalizing Your Weekly Running by Using Power
I had a great time broadcasting live today with Evan from Stryd on their Facebook page. You can see the whole video (25') online here: https://www.facebook.com/teamstryd/videos/408831879692264/
One of the questions he asked me was about the running stress score. Inside Stryd Powercenter this is known as the RSS, those of you who are familiar with training peaks would know this as rTSS.
Evans specifically asked how to use this stress the score instead of tracking weekly mileage. I pointed out that the Stress score allows an athlete to Effectively normalize their weekly training. Instead of always running 25 miles, where any one of those runs may be significantly different from week to week, running to a stress score would allow you to ensure that your running, regardless of intensity or distance was of an equal or higher stress than the week before.
In other words, Athlete A runs 25 miles with much of it at tempo. Athlete B runs 25 miles with much of it at recovery pace.
At the end of the week, they have both Run 25 miles.
But those two weeks are fundamentally different. The athlete who has done more a tempo has earned more stress. Where is the athlete running at recovery pace has had a very restorative week.
What do you think of this concept. Do you think it's useful on a weekly basis to track training stress And plan a progression? More useful than miles?
Comments
Definitely more useful than miles. I manage my run builds with TSS now. I like TSS better because of the ability to control ramp rate and TSB.
Before Stryd, I used normalized graded pace (NGP) to calculate rTSS. Since Stryd, I use threshold power to calculate TSS. I think it is a much more objective measure and like it better.
Time distance and power are all important metrics, and none should be totally abandnded. I like the idea of training to a Stress Score. But I am a triathlete, not a runner. So my rTSS may vary from week-to-week, but my overall CTL. should build towards a plateau about 8-6 weeks out from my goal race, hold steady for 4-6 weeks, then slowly drop to gain form.
within that framework, my rTSS may bounce up and down as my weekly training emphasis evolves around the 3 different disciplines.
Were I solely a runner, say doing 4-12 weeks of run durability, or training for a specific running goal race, then I do like the idea of a progressive increase in power-based run stress score during that training.
Further thoughts...Stryd's calculation of "power" relies primarily on pace with adjustment for gradient...how rapidly and far the foot is moving thru each of the three planes of motion. So it is IMO another way of presenting NGP.
Going back to what a long distance triathlete should focus on : (1) steadiness of effort. "Power" helps with that. (2) Time on feet...power can help here as a check to help avoid "too much " work (and the concommitant njury risk) while accumulating that time.
Finally, consider the absurd example...in an effort to save time in training, a runner with an 8:40 min/mile LRP does all her training at 6:30. She gets the same stress in, say, 90 minutes as she might if she ran @LRP for 3 hrs. Not good unless she's getting ready for an assault on her mile PR. Training focussed on a single metric will miss other important aspects of training.
I am not a stryd user but I believe too in using TSS VS mileage.
For me its time>TSS>Mileage. Can maybe a TSS ratio with time or mileage can be an interesting metric ? For goat running we like to look at elevation/mile.
I also think you need to look at what is your goal in your runnings aka specificity of your training. If you are training for a fast short distance, than TSS is interesting, if you are training for an ultra I believe time on your feet is the most important metric and if you are training for a long distance triathlon TSS is a good indicator as you have to manage a weekly TSS volume that is coming from 2 other sports.
@Al Truscott makes a great point... there is no single "goldilocks" metric for training. I like TSS for loading because it considers both time and intensity and because it feeds directly into CTL, which is a big part of my training.
While TSS is directly related to time, it doesn't give any insight into "was that a sprint " vs "was that a long and steady" workout.
Since intensity contributes as the square in the TSS formula, 100 TSS is the equivalent of running at threshold/FTP/CP for an hour, running at 70% for 2 hours or running at 50% for 4 hours.
I understand correctly, this is the point that @Francis Picard is making. I'm not sure that it fair, for example, to say that a 10+k race has the same stress effect on your body as a 4-hour run @ 50%, even though both result in ≈100 TSS. So trying to use TSS for ultra distance running would require the targets to be adjusted; The TSS loading targets we use for marathon training would be wrong and it is probably more reliable to just focus on the time as a better understood gauge for weekly work.
I am not as well versed on TSS and thus far have only used Stryd to accumulate data. I am thinking though, at some point my coach will have me start paying attention to power. Will he tell me to try and run a certain power number for my IM, uphill & downhill? If he does, is that any different than running on Pace? A few years ago we went from Pace based running to HR based running. HR allows you to deal with many variables, hills, heat, humidity, etc. Won't trying to stick to a power number effectively bring us back to the problems that pace vs HR raised?
as an aside, a major competitor to EN does all training, on HR..
Great points all...and I really like the reminder that no two TSS runs are the same. I think a next generation statement on this might be that using TSS for a normalized training week is effective if you are on a set plan.
IWO, Monday Strides, Tuesday FTP run, Wed Long run, blah, blah blah...
Assuming you repeat that week, then TSS becomes more useful as the runs are "controlled"....I would also be okay giving runners a "swing" day, say where you can earn your TSS through manipulating the Intensity Square to save time. Too much of that stuff, though, and you can run into trouble.
Regarding @scott dinhofer trying to derail this enter conversation about training weeks, yes, you will run with power on race day. The same way we ride with power. Power is instant, HR is gradual / accumulated. If you want to wait 15' to see if you ran the first 5' of your IM marathon too hard, and pray you didn't, then just use HR. The value of power is a real time data stream that allows you to create the conditions that will generate the HR you want. #nextlevel$hit 🤣
Is #nextlevel$hit an official tag? 😁
Another aside, TSS is in our training plans. Are we supposed to have TSS on our watch and pretty much keep riding until we get the right number or ??? I don't suppose we'll see RSS/rTSS in our training plans until the Stryd becomes the norm on EN.
Following the model, I have concluded that it was theoretically impossible for @Jeremy Behler to have run a KQ marathon at lake placid last year following his injured/run limited season
I have reached out to WTC to inform them of their error. :)
@Dave Tallo this is a good analogy for my IMLP run last year...
YES. I think tracking/using TSS derived from STRYD to be preferred, vs. pace/HR/time derived TSS. However, I do find power TSS to correlate very well with mileage as indicated in my 2 charts below , which has a tremendous amount of variability via road/trail , hard/easy , and race/training. IOW, I think it would be very difficult to raise or lower daily/weekly TSS without raising or lowering the mileage associated with it and vice versa.