IM Run Pacing/VDOT
Should I use a slightly lower VDOT to calculate a more accurate/realistic IM run pace? I know I have seen some stuff posted on this in the past but am looking for some refresher guidance here. My current VDOT based on my 5K time trials is 54 (18:36). However, my VDOT based off of numerous Half Marathons is right around 52 (1:30:00).
So should I use my 5K VDOT (seems to fast for an IM), my Half Marathon VDOT (still too fast?), or something else?
Also, if I plan on walking the aid stations each mile for 30 seconds, do I add this time onto my goal pace per mile or am I actually running a little faster than this per mile to make up for the walking time? For example, let's say that using my VDOT that my E pace is 9:00 per mile. Am I running each mile in 9 minutes and then adding on 30 seconds per mile so that my actual accumulated time is 9:30 per mile? Or do I run each mile at approximately 8:30 or so and then when the walking time is added in it brings me to a cumulative time of 9:00 per mile? Note here I am not addressing the issue of running the first six miles slower or other factors (i.e. heat), I am just trying to get a feeling of how to incorporate the aid station walking into my pacing.
Thanks for your feedback!
Comments
Your race day VDOT = 52. Coaches and others recommend dropping 2-3 points of your 5K VDOT for an IM pace. I myself routinely use my most recent HM VDOT for race day.
Total time/mile predicted from this VDOT would include any strategic (planned) walking you do @ aid stations, although 30 sec sounds like a bit much for someone with your speed. And don't forget to use the heat pace calc to adjust your target pace.
You'll probably find your target pace/mile to be a rein for the first 5-6 miles, then a whip for the last 5-10 miles.
Al,
Thanks! Very helpful. Although a VDOT of 52 would yield me a target IM run time of around 3:42 (before any heat adjustment). This still seems too fast as my fastest IM run was 4:20 last year in Arizona.
Would you suggest dropping my VDOT down another point or two to come up with a slightly slower pace or sticking with The 52 and then adapting accordingly on race day?
Thanks agin for your help!
There is a run/walk calculator available in the Wiki..very cool. just plug in your running pace, and est. walking tim/distance per mile and you'll get your projected finish time...then you just have to focus on running your target pace and the amount of time you walk at aid stations...
Dan - It sounds like your bike execution might be off a little bit if you are slowing that much from your normal run time. I will start by saying that I am a crappy runner. My normal good conditions marathon-only time is around 4 hours, but my IM in the blazing heat time is 5 hours. You like like a 3+hour marathoner, so your IM marathon probably shouldn't be 1:20 over that pace. Just something to think about. I would defer to Al, Tom and some of the other fast runners in the group.
Dan - I ran a 4:15 in IM AZ last fall with a pre-race VDOT of 46.6 based on my recent HM time (1:37.05) and a plantar fascia injury, and two years prior a 4:03 with the same VDOT, injury free. If you can run 18:36/1:30 for 5K/HM, then with proper race day execution, you can indeed expect to go a *lot* faster. Follow the EN biking and running rules religiously on race day, and it will happen. Your jaw will drop on the finish line when you see your marathon time.
I am a relatively weak cyclist (6:30-6:45) and just got a power meter for the first time. So I am hopefully that riding the bike leg at a more even, steady pace will leave me fresher for the run. Thanks again for your feedback!
Dan, last year at IMLP I ran a 4:36 marathon on a VDOT of 46. This was my first Marathon and first IM. I'm now at a VDOT of 51 for 5K and just ran a 1:36 HM on a very hot, humid, sunny day. Once I drop in my IM training plan for IMFL, I will drop in a Vdot of 49 into the training plan to see how that feels for longer runs. Right now I can sit on 7:50 and run for what feels like forever if you put an IV in my arm. Not sure how that will feel once the bike volume goes up. For LP I did not have a Power meter on my bike and didn't wear a GPS for the run. I now have both which I feel will give me a huge advantage. I also plan on executing nutrition better for race day.
The thing I wrestle with is my mental state of, "could I really run a 4 hour or Gasp, a sub 4 hour marathon at the end of an Ironman"...for nothing else, it keeps me really motiviated at this game of ironman. There are some serious demonds on that run course at mile 18 that I'm looking forward to battling with.
Dan - jsut to add some practical experience to the discussion....were not that far off...I'm a 19 flat 5k & 1:34 HM (3:24 best open marathon over age 40 I once ran 2:40)...anyway...I did IM Louisille last year and probably was similar on the bike ( I rode 6:20)...my marathon was 4:16 and included about 15min. of walking between mile 21-22 were I had a fluid/dehydration/almost passout issue...once I made it to the aid/water station and refueled/hydrated I finished normally....
My current vdot is 52...which says I should have an open marathon pace of 7min & LP of 8:08...coming out of OS my long pace endurance stamina is nowhere near allowing me to run and open marathon @ 7min. pace (I haven't trained for it)...so I will taret the 8:08 but more realistically I would like to think I can run 8:30-8:45 pace for Louisville this year (assuming it doesn't get unbearably hot)...so that kinda harmonizes with the +1-1:30min/mi advice...
The other key thing that will help is that I have put in more work on the bike this year than last year...so should come off the bike leg fresher (if I play it the smart EN way - I also purchased a powermeter this year..I used HR last year)....and of course experience with nutrition/hydration.
Good Luck to you.