Tuesday, September 10, 2013

Diamondman--and the implications for Tahoe

So I raced Diamondman this past weekend--tough day in the office.  We were thrown a bit of a curve ball with very warm, breezy and humid conditions (and a longer, mis-measured running course).  It was a real sufferfest for me (and many others) out there for sure.  My swim was a bit off as was my bike but I really crashed on the run.  There wasn't enough fluid on the course and I probably didn't react aggressively enough to the enviromental challenges and got way behind on my fluid and energy.  I defintely paid the price.

In any event, it was a very hard fight I fought to get to the finish line and still hold on to my AG victory--which I did (I'm 7-3 this year....) so I take solace in that.  I did get some good power data, which I think alows me to set a power target for Tahoe:

1. At Diamondman I averaged 201 watts (204 NP) with a HR of 153bpm.  My Garmin tells me this equates to an empirically derived IF of 0.772.  Normally, I'd want my IF to be 0.85, which means I probably should have done 221 watts for this race but given my high HR, either I had something going on in this race that was holding me back or my body was diverting resources to try to cool things down a bit.

2. In any event, an IF of 0.772 implies my actual best FTP this year is 260.4 watts (this is what I have demonstrated in my races this year).  I have achieved 280 watts on my computrainer.  If I use the lower number as my FTP, then this implies an target wattage for my IM of 182-187 watts.  The higher number yields 196-202 watts.  The lower target implies my IM power will be 7-9% lower than my H-IM power.

3. In comparison, here is how some of my prior H-IM/IM races have gone:

2007: White Lake Half: 228 watts/IMFL: 211 watts (IM is 8% lower)

2008: Gulf Coast Half: 222 watts/IMAUS: 168 watts/IMCAN: 185 watts (17-24 % lower)

2010: Oceanside70.3: 174 watts/Kona: 170 watts (2% lower)

2011: SkipJack: 221 watts/ IMAZ: 184 watts (17% lower)

2012: Shoreman H-IM: 201 watts/Kona: 174 watts (13% lower)

4. This data is all over the place but I draw the following conclusions:

- My best two H-IMs were WL07 and SJ11 where I averaged 228 and 221 watts respectively.  I was a lot fitter in 2007 than today and I think that I'm similar to where I was in 2011.  My current FTP tells me that I should have hit 221 watts this past weekend but I didn't.  In truth, most H-IMs I can't hit 85% of FTP--I probably did in 2011 but my effort in 2007, as good as it was, was probably below my potential on that day.  I conclude 2011 was probably the best model for me and I hit 184 watts reasonably comfortably at IMAZ that year.
- I didn't have a great day on Sunday, only hitting 77% of FTP and this tells me that I'm better off using the lower FTP number for purposes of planning for IMLT.

5. Therefore, I would normally think the right power target for me is 180-190 watts.  When I hit 184 watts at IMAZ in 2011 this yielded a 5:25 bike split, which leads me to believe I'm looking at 6+ hours at Tahoe....a sobering conclusion for sure.

6. Beyond that, I'll be keeping these things in mind:
- At 6-7,000 ft+ of altitude, I'll have to carefully monitor my perceived effort and be prepared to back off.   Most of the data I've seen says at this altitude you lose about 10% of your FTP--this would imply knocking my target range down to 160-170 watts.  Even if I used 280 watts as my FTP I'd still get 175-180 watts.  These are pretty scary numbers--this is going to be a very long bike ride.
- I think I didn't have the best day on sunday.  I certainly wasn't fully tappered.  Perhaps, I'm being a bit negatively biased by that....
-competitively, to get the Kona slot, I've got to make it happen on the bike to have a chance--this tells me I need to be prepared to roll the dice a bit.

So based on all of this, my plan is:

lap 1: 175-180 watts/limit my peak power to 200-210 watts on the two big climbs
lap 2: the same or perhaps change target range based on how I feel.  If I feel good, go up to a max of 180-190 watts/same hard limit on the climbs.  If I'm a bit stressed, I'll back off.
lap 3: whatever makes sense at that point
Based on competitive feedback, decide how to make tactical adjustments to this plan on the fly.

I'm heading out there on Monday and plan to recon the course quite a bit so I should be able to get a better sense of the merits of these thoughts as I put some test miles in on the course....

More on this later as well as my Diamondman race report....

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