Training Peaks and rTSS

wellboss

Hi all

Looking for some help with understanding the run TSS scoring system in training peaks

rTSS = S * NGP * IF / FTP * 3600 taken from training peaks website

https://www.trainingpeaks.com/blog/running-training-stress-score-rtss-explained/

Where
NGP = normalised graded pace - pace adjusted for elevation changes
FTP = functional threshold pace - based on average pace on 45-60min run
IF = Intensity frequency = NGP/FTP


The reason I started wondering about this was I noticed my IF was very high for an easy 10km run, .94, if it is comparable to biking that was way too high for my effort level. if my IF was too high surely the rTSS isn't reflective of my effort

stay with me, if IF = NGP/FTP i can't see how i even get a figure below 1
my threshold pace is around the 4:00 mins per kms and my NGP from an easy 14km run tonight was 5:00 pace

therefore based on above my IF should be 5:00/4:00 or 300s/240s which equates to 1.25

how is training peaks coming up with IF of .94?

Can any body help explain this or have they come across it

Kurt.Godel

Your formula is incorrect. It should be rTSS = S * NGP * IF / FTP * 36

Kurt.Godel

I don't understand this either. I looked at a recent run just over an hour (3602s), Training Peaks says my rTSS=110, with an IF=0.99. Using the formula:

rTSS = (S * NGP * IF) / (FTP * 36)

and substituting for rTSS, S, and IF

110 = (3602 * NGP * 0.99) / (FTP * 36)

and computing (3602*0.99/36) = 99.055

110 = 99.055 * (NGP / FTP)

and substituting for IF = (NGP / FTP)

110 = 99.055 * 0.99 = 98.06445

which is clearly wrong.

Kurt.Godel

After the above run Training Peaks suggested I update my Threshold pace, which I did to their suggested figure. I subsequently did another run just over an hour (3665s), Training Peaks says for this run my rTSS=99, with an IF=0.94. Again using the formula:

rTSS = (S * NGP * IF) / (FTP * 36)

and substituting for rTSS, S, and IF

99 = (3665 * NGP * 0.94) / (FTP * 36)

and computing (3665*0.94/36) = 95.6972

99 = 95.6972 * (NGP / FTP)

and substituting for IF = (NGP / FTP)

99 = 95.6972 * 0.94 = 89.9554

which is also wrong, but slightly more accurate than the first example.

I suspect the error is caused by Training Peaks prescribing an non-accurate FTP.

Keeks

In teh absense of Power, i imagine it is lookign at HR to get an IF value.....see below

https://www.trainingpeaks.com/blog/normalized-power-intensity-factor-training-stress/

Typical IF values for various training sessions or races are as follows:

Less than 0.75 recovery rides
0.75-0.85 endurance-paced training rides
0.85-0.95 tempo rides, aerobic and anaerobic interval workouts (work and rest periods combined), longer (>2.5 h) road races
0.95-1.05 lactate threshold intervals (work period only), shorter (<2.5 h) road races, criteriums, circuit races, longer (e.g., 40 km) TTs
1.05-1.15 shorter (e.g., 15 km) TTs, track points race
Greater than 1.15 prologue TT, track pursuit, track miss-and-out

Kurt.Godel

That is for bikes Keeks- looks like they use a pace-based method for runs. FTP should be close to a recent 45-60min race pace.

https://www.trainingpeaks.com/blog/determining-functional-threshold-pace-ftp/

Keeks

Yep, pace is what they seem to use....but I was only quoting the typical IF values as it also showed what you would score for road races....

Pace for running and Power for cycling and then broken down into zones it would seem

Typical IF values for various training sessions or races are as follows:

Less than 0.75 recovery rides
0.75-0.85 endurance-paced training rides
0.85-0.95 tempo rides, aerobic and anaerobic interval workouts (work and rest periods combined), longer (>2.5 h) road races
0.95-1.05 lactate threshold intervals (work period only), shorter (<2.5 h) road races, criteriums, circuit races, longer (e.g., 40 km) TTs
1.05-1.15 shorter (e.g., 15 km) TTs, track points race
Greater than 1.15 prologue TT, track pursuit, track miss-and-out

pgibbo

An important thing to note is that the creator of TSS reckons swim & run TSS are BS. Seen him mention it numerous times over on ST.

A lot of people still uses it but he doesn't rate it.

wellboss

Kurt.Godel wrote: »

Your formula is incorrect. It should be rTSS = S * NGP * IF / FTP * 36

Where did you take this equation from? the one from training peaks has it at 3600 rather than 36 that you are using??

Even forgetting about the main equation I am just baffled by the IF(again assuming it's comparable to biking IF), using the formula NGP/FTP (which is plucked from the TSS formula) how can it ever be less than 1, unless I go and hammer myself and my NGP is faster than my threshold pace

as stated above
my present threshold pace is around the 4:00 mins per kms and my NGP from an easy 14km run tonight was 5:00 pace

therefore based on above equation my IF should be 5:00/4:00 or 300s/240s which equates to 1.25

Now if i switched it around was FTP/NGP it would be .80 and would feel perfect for how I felt on the run


I normally just run as I feel for endurance and tempo, i know my body pretty well from years of doing it but I wanted to make sure I was doing it based on science but i am starting to think its BS also, think ill just stick to what I know and use TP to track biking and Miles/KM. bit disappointing overall as I was enjoying TP

Kurt.Godel

wellboss wrote: »

Where did you take this equation from? the one from training peaks has it at 3600 rather than 36 that you are using??

From your link- you have omitted the *100 multiplier to the right of the main equation. 100/3600 = 1/36

wellboss wrote: »

my present threshold pace is around the 4:00 mins per kms and my NGP from an easy 14km run tonight was 5:00 pace

therefore based on above equation my IF should be 5:00/4:00 or 300s/240s which equates to 1.25

Now if i switched it around was FTP/NGP it would be .80 and would feel perfect for how I felt on the run

I don't think the ratio for IF is time/time, rather they ascribe a figure to your NGP as a function of your FTP, so your 80/100 would be more correct (I don't know what the function is but I presume its exponential). However, they do appear to use time in seconds for FTP and NGP for the larger equation, and using the prescribed IF figure along with "time in seconds" for FTP and NGP, makes the longer equation more accurate (at least it does in the couple of examples I used above). Essentially they calculate NGP/FTP in two different ways.

wellboss wrote: »

I normally just run as I feel for endurance and tempo, i know my body pretty well from years of doing it but I wanted to make sure I was doing it based on science but i am starting to think its BS also, think ill just stick to what I know and use TP to track biking and Miles/KM. bit disappointing overall as I was enjoying TP

You're going to know your body much better than this equation would! There are a lot more variables involved in calculating a running score than there would be using Wattage for a bike score.

wellboss

I am obviously taking the simplistic way by just plugging the time values for those metrics as I only see them measured as time, they are both pace values. It's more the nerd in me that wants to understand this rather than the actual value it gives my training. think its time to forget about it and just use my TSS value given and it will be relative to training effort put in and will still represent easy and hard sessions.

cheers for your help

tunney

Sigh....

Kurt.Godel

tunney wrote: »

Sigh....

Transmitting positive vibes your way tunney