Help with TSS from IM pacing guidelines
Hi All,
Need some help re: the TSS table for IM bike split. My understanding is that you estimate your finishing time and your "planned" IF and then look at the TSS. The TSS then tells you whether you set up your run well or boogered up the bike.
IMWI will be my 2nd IM. Last year did it pre EN-played it real conservative, rode 130 W (had never tested FTP), 7 hour bike split. Now, post EN, FTP is up to 234 W and noticeably riding better/faster. So IMWI plan is 160s, IF ~ 0.65-0.70. That said, still think my bike split will be > 6:20. The TSS tables don't account for "longer" IM bike splits so how does one "plan" for their TSS.
As a related question-does TSS=TSS? Meaning is a TSS of 220 after a 4.5 hour ride equal to a TSS of 220 after a 6 hour ride-ie. same cost to the body?
Thanks
Venkatesh
Comments
It says that for a longer than 6 hour bike split for IM, just stick with an IF of 0.69 to 0.70
Cheers
Peter
I have a follow up question as well. My bike split is looking like 6ish hours, maybe a little more. If I'm targeting .7 IF, but I'm riding the first 1 to 1.5 hours at .67 (1st gear) and riding the remaining 4.5 to 5 at .7 IF that's going to result in an overall IF < .7 (.692 to .695).
Is this normal, and what's expected? If I target .7 and end up with .69 in WKO, thats still ok right?
Our coaches have often pointed out that not all TSS points are created equal. It depends on how you generate that score. A long, steady ride with a very low VI - say a 6 hour ride @ 0.62 IF and a VI of 1.02 - will probably be easier to recover from than a 4.5 hour ride which featured episodes of intense VO2 work or FTP intervals, or was generated on a group hammer session with 2-3 other riders sharing time at the front pulling @ 0.95-1.00, then resting behind @ 0.75-0.8.
Your own sense of fatigue after your rides is a better judge of the cost to the body than the Training Stress Score, which after all is a pure mathematical construct, not based on a physiological assessment.
Through observation and experience we've learned that an 5:xx ride at 75% at 330 TSS is not the same as a 6:xx ride at 68-70% at 330 TSS. The later...you're probably fine. The former...you're done, better luck next year, enjoy yourself on your loonngg walk on the course.
In short, the TSS construct is not perfect. I would say that the difference between a 310 TSS ride @ 69% and a 340 TSS ride @ 68-9% is largely the fatigue associated with sitting on the bike, and pedaling, for a long ass time. You can essentially go all day at 69-70%, though your ass, neck, shoulders, and headspace will not be happy.
As you scale upwards from 69% to 70 to 71 to 72, through 75%, the tired you feel is very much from actually "riding" your bike. Muscle fatigue, stuff like that. As the % goes up you are actually working harder and harder.
I would say that probably 80% of the IM field, especially the guys, is riding that very common 5:40-6:10 bike split at 75-77%. That 75% effort is "maybe" appropriate for a 5:15 bike split, assuming excellent bike endurance and run fitness. So by every minute they are out there longer than 5:15, they are piling higher and higher TSS into their legs.
You could say that the typical IM athlete limping it in the last 30-50' of the bike -- done, sitting up, dreading the run -- is doing so because they are spooling their legs up and over 285, 295, 300, 310, 320 TSS. When you add poor gearing, very surge-y riding on the hills, this too-hot, too much TSS scenario just crushes the run and most people's races are done and in the can by about mile 90 of the bike...they just don't know it yet.