Ironman TSS Budget

IMOO. Ran well, I'd say b+ on the run.

I'd be really suprsed with a good run with someone posting 360 TSS. Do you have a sample race report and data for that?

Entire workout (157 watts):
Duration: 5:57:56
Work: 3375 kJ
TSS: 273.1 (intensity factor 0.677)
Norm Power: 167
VI: 1.06
Pw:HR: n/a
Pa:HR: n/a
Distance: 113.196 mi

I would be very cautious at planning your race based on TSS as it might or might not apply to the best pacing strategy for you. While certainly there is in general a range in which many AGers fall when racing IM, there are those very fast AGers or those a tad slower that fall of this range. In addition, your specific fitness might result in a lower/higher TSS give your specific strengths. Another things to conisder is the fitness gains you'll have on the last weeks of training and tapering hence unless you test close to the race which might not be the best idea then pacing based on TSS might limit your performance.

If you have data from your long rides you can use TSS but IMO avg watts (on race rehearsals) and kJ can be better info for your racing.

Jorge, why would KJ or avg watts be better than TSS? Wouldn't avg watts or KJ be limited similar to TSS?

Wouldn't KJ or avg watts be effected by accurate testing close to race and possibly not see the gains from fitness and tapering as TSS could?

I agree with KathyG. My Ironman racing zone is 68%-78% of my FTP but I learnt from HIM racing strategy that extrapolating the average watts from TSS budget is a better strategy and it fits great to me using 170 for HIM.
Why that? In april, in my first HIM with power tap, I set 80-85% as goal for average watts in the race. The race was flat more or less and I did 83% with 170 TSS and it was perfect for the run.
After a month, again around 82%, the duration was 3mins only longer and the TSSS around the same. Perfect run.
Then I experienced the meaning of TSS: I went for another HIM, very hilly, it took 15mins more and the TSS was 200 with 87% average power. I collapsed on the run.

I went in deep on the Allen Coggan book and I understood that, starting with the TSS budget (170 now works well for me), especially on a hilly course like IM Switzerland, it is the best way to pace your race.

and yes, I am going to test myself the week before the race, next week.

kJ is energy expenditure generally is related to your weight. For a given distance, it will roughly take you the same amount of kJ to go that distance at the same weight regardless of how hard or not you go. For instance, if you ride 50 miles at 90% or 70% of your FTP the total kJ will be roughly the same, it is just how you chose to spend those kJ; when you go harder you can afford to spend those kJ in that way because you'll be riding for a shorter period of time and viceversa. Avg watts on the other hand is the total work done which IMO is representative of how you rode the course (i.e. whether you coasted a lot, spiked your power, stopped, etc).

So to answer to your question, no,  kJ won't be affected by fitness level as long as your weight remains fairly constant which it usually the case on the weeks leading to the race and why I suggested using info from race rehearsals. It will 'cost' you roughly the same energy to go the distance at the same weight on race day, where fitness comes into play is how fast or what % of yuor power threshold you can cover that distance.

If you know it takes you around 1500 kJ to complete 56 miles at your current weight and in training you know that sustaining 80% of your FTP roughly equates to an 'x' split which allows you to run well off the bike now you know what's your 'budget' for the race. In addition, you can use kJ to develop your nutritional plan and use it to dial it in training.

I think TSS or BikeScore or any other calculation used to quantify load is very useful because it considers exercise duration x avg power x weighting factor (IF), yet for racing I am still not yet convinced, it is the best way to pacing a race, besides unless you have a joule you won't know your TSS for sure during a race but that's beyond the point. At this point, I think it can be redundant or even somehow misleading.

TSS/BikeScore were originally developed to quantify training load and attempt making better training decisions. Still, since the robustness of the info depends on the averaging weight factor which is based on the accuracy of our power threshold and considering fitness changes can happen leading to a race it might not be the best way to go, though that's IMO.

Finally, those who have used any of those algorithms to quantify load also know that other factors such as short and long term nutrition, rest, etc. have an impact on performance even though it the TSS might not suggest that hence using those also requires the use of common sense and consideration for the particular needs of every athlete beyond the number itself.

well, as I said, TSS = exercise duration x avg power x IF, hence it is not surprising when you pushed harder on a race, it not only yielded a higher TSS but also resulted in a poor run. There is certainly a correlation between what TSS an athlete would usually yield when pacing well. The problem is that one can have a good or bad race and the TSS be outside of the 'norm' what some have considered optimal. Hence, for me it is hard to place all my hopes in one metric when there is evidence to the contrary.

I think it is common sense to assume that proper IM or HIM pacing is related to the power duration curve, that is, from your sustainable power at different intensities, there will be an optimal pacing limit for you, given your specific swim and run fitness. IOW, if your power threshold is 'x' and your sustainable power for your goal distance is 'y' then somewhere in between in the relation between power/duration curve there will be limit (range) of how hard or not you can go, if you want to have the energy to perform well during the run.

Anyway, was the distance for all HIM really 56 miles? If so, what was your kJ and has your weight fluctuated much or remained fairly constant. how accurate was your FTP before each race (when was the last time you tested before each race?)

I am not trying to convince you to go one way or another, you can choose to do whatever you want. I am just sharing some of my experience which goes beyond n=1, but considering many power files I've seen. In addition, the whole racing with a TSS budget is not necessarily new and its something I (we) something we (a bunch of coaches including the likes of Strauss, Whyte who wrote the TSS pacing paper, Perham, Digman, etc) have considered for ~3 years. Dr. AC has chimed in a few debates about TSS and even he conceded while TSS could be considered, applying it for pacing might go beyond the scope of what it was intended for and other variables should be considered as well specially when pacing IM which still involves running off the bike.

Whyte who wrote the TSS/IM pacing paper also agrees it is hard to place all your pacing on one metric and quote him "Again, no ONE single metric should ever be used to determine success or failure. We highly suggest to use TSS in conjunction with other global descriptive metrics during post-race analysis" (emphasis mine).

For those reason, I've have chosen to not set up race strategies for my athletes based on that.