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IM Run - The Golden Hour - Advice Needed

I've been reading a lot of race plans / reports and thinking about the advice that you, the coaches and others have given me... and I realized that I am hearing but not understanding the advice on starting the run.

The EN protocol is to start the run +30 sec over target pace. Coach P talks about getting his heart rate down when he starts the bike and starts the run. Nearly all the Kona crew were talking about getting the HR down at the start of the run. Al referred to the "golden hour" in his recent critique/suggestion for my IMCoz race plan. 

Maybe I just don't understand how we are supposed to do it... my IM plans would typically have me on the bike in the 140s, off the bike in the 150s, on the run in low 150s and trying to keep it in the high 150s, low 160s on the run.

Here are typical numbers for me... 

  • My 5k run HR avg is ≈177 for the last 10min. Max running HR just over 200. My avg HR during FTT also ≈177 during the second half of 20-min test, it peaks just under 190 on VO2 test. Anerobic Threshold ≈170
  • IM Bike HR typically starts in the 140s and works its way to the low 150s.
  • IM Run HR typically starts in the low 150s and works its way to the mid 160s 
  • Long Run (Z1, then Z2, then best effort) HR typically starts in mid/upper 140s to ≈150, moves to lows 160s then peaks on best effort
  • Half Marathon HR starts in the low 160s, works to 170ish then the last couple miles in mid/upper 170s

Should I / is it possible to drive my IM running HR down close to the long run numbers?

What else is happing during the "Golden Hour?"

What am I missing / executing wrong?

Thanks!

Comments

  • Am I the only one who thinks 160s is too high for an IM run when your 5K effort averages 177?
  • That's about my 5K avg HR as well.

    Last week at IMAZ I got off the bike in the low 140s (284 TSS total) and kept my HR below 145-146 up to mile 13 then let it float to 150 thereafter......

    That strategy had me running a bit faster than my vDOT IM race paces but it was only 70 degrees and no humidity.

    I PR'd my IM run at this event.

    SS

  • @Shaughn - when you started your IMAZ, did your HR want to go higher so that you had to work to keep it low? Or did it just settle in at that level? What HR do you do your long runs (Z1 our / Z2 back) at?

    I have near no runs with HR in the 140s unless they are on a treadmill. As a matter of fact, I have more runs with a max HR = 185 than I do with an average in the 140s...

    Could be that I am doing it wrong?
  • "Golden hour" meant to indicate that the first hour of an IM run is about the only time when you have an opportunity to keep your hydration status topped up (assuming you kept it that way during the bike). With the slower pace/lower HR, there will be enough blood flow thru the gut while you walk the aid station to absorb sufficient fluid. If you run too fast/hard during those first six miles, you will just bring forward the time when you become more than 2-3% dehydrated, which is when slowing down will inevitably start.

    Key data in Rich's post: 

    • "My 5k run HR avg is ≈177 for the last 10min. Max running HR just over 200.[Emphasis added] My avg HR during FTT also ≈177 during the second half of 20-min test, it peaks just under 190 on VO2 test. Anerobic Threshold ≈170"

    He says his Max HR is just over 200 and just under 190 for VO2 test. So IMO he is either not sufficiently trained to run an all out 5k, or he is not working hard enough if he is hitting 177 during the last 10 minutes. 180-190 would be the target for him. Let's say his Max HR is 200; in that case (again, my opinion), his HR should start @ 72-75% of his max, or 145-150 during the first 8 miles of the the IM run. Then, sit in the range of 75-80% until mile 15 or so (150-160). Then, it can drift up to a max of 84-5% (165-168) by the end, assuming he is (a) sufficiently hydrated, (b) on top of his nutrition, (c) rode a very steady bike within his prescribed IF, (d) and has command of the dark side after mile 18. Note this brings him up to a point where he is being asked to run for less than an hour *just* below his anaerobic threshold.

    This is the ideal, IMO. It requires KMF style training, EN ninja race execution skills, and experience at dealing successfully with the dark side in that last hour. All others should aim for a lower HR, but 75 % should be the lower limit during that last 20 miles of the run.

    Now, if we want to use Rich's 5K HR as the measure, then we'd have to drop all those numbers probably 5% or so, if the 5K is presumed to be the best reflection of his fitness.

    Rich, the main point is…you can never run too slow during the first six miles of the IM marathon. Thats why we call it "stooped slow" - we all feel like we could go faster/harder, but have learned we shouldn't.

  • @Al - thank you for reading this and spending the time to help me.

    I have been suspecting a variation along the lines of your first instinct "So IMO he is either not sufficiently trained to run an all out 5k, or he is not working hard enough if he is hitting 177 during the last 10 minutes." Prior to EN, my recent running history was all long and slow or long and steady.

    I don't know how to create the equivalent of a Power Duration Curve that is based on run pace, but if I had one, I suspect (based on my history) that my "hour pace," and my "two-hour pace" would be significantly higher than my 20-minute pace. I recently ran in a half marathon and my average HR for the entire run was 172, peaking at 178. The course was flat - my higher Max HR runs always happen when there is a hill at the end of the race.

    I have not had a full Outseason (raced IMLT in late Sept followed by IMLC in March) and injuries interrupted a large chunk of my running season this year. Maybe a Run-focused Outseason will push the left side of my "Run Pace Duration" curve faster... ??

    In the mean time - as I look at IMCoz - I think I should revise HR targets lower. Normally I get off the bike in the low 150s and pick up from there on the run. Sounds like I should use the first 6 miles to really try to force it down to ˜145-150, let it climb to the mid 150s through mile 18, then do what I can.

    Once again - thank you!
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