Does anyone know if there are formulas out there that could estimate a 70.3 finish time using an Olympic finish time. I know runners world offers a formula that reasonably puts you in the ballpark. Just wondering if shooting for a sub 6 hour is reasonable using a 2hr 27min finish time for an Olympic. I figure the bike and run are a little more than twice that of the Olympic but the swim is only .45 miles more (coincidentally my weakest of the 3). This is ofcourse not factoring in possible weather conditions like heat, etc. Thanks for the input.
Charlie
This is a tough one. At least in my experience, going from an Oly to a HIM is a completely different animal becuase of nutrition. FWIW I did my first half last year and I bonked hard. I was no where near the finishing time I had predicted. In an Oly you can get by on water and maybe a few gels and or sports drink. If you have your nutrition dialed in then a sub 6 is probably doable, but (and I’m assuming) if this is your first half, make sure you get out there and train with your nutrition as you plan to use it on race day. Don’t learn that the hard way like I did. Oh yeah, don’t set a time goal for your first half or full, just get out there, do it, finish it, and learn.
In 2005 I did:
Oly 2:17 HIM 5:06 ratio = 2.2
In 2007 I did:
Oly 2:05 HIM 4:23 ratio = 2.1
So assuming the ratio increases for a 2:27 to 2.3, that gives about a 5:40 HIM time. I say go for it!
My $.02
Guessing your 2:27 was something like
25 to 30 min swim
1:10 to 1:15 bike assuming that is near your FT
42 to 47 min run also assuming that is near your FT
Do those sound about right
I would add 10 minutes onto you swim time
If the bike courses are similar then near a 2:40 bike
Then target a 1:45 to 1:55 run
Add in about 10 min of transistions and it still appears you come in well under 6 hours
If anything I might take it easier on the bike to ensure a good run.
jaretj
Last year I did my first HIM in just under 5:40, and my previous best OLY had been 2:45, although on a very hilly bike course. I paced the bike conservatively and followed my nutrition plan and passed loads of people on the run who were walking in the heat, including several friends who do sub-2:30 OLYs. If you have a good base for the distance and you race smart, I think you could maybe do sub 5:30 for the HIM or even faster. One of my friends who did 2:24 at Boulder Peak last year was right around 5 hrs for the 5430 Long Course HIM.
But I don’t know of a conversion chart for tris that would be similar to the estimated finish time calculators for running. Too many variables I think.
26 minute swim with wetsuit, 1 hr 8min bike, 45 min run. Your estimates are right on and I pretty much did your exact calculations, but I’m not certain as to what the overall fatigue factor will be and couple that with the Florida heat and I’m hoping for sub 6. I feel that running is definately my stronger suit so hopefully I can use that to may advantage since that’s what seems to give people the most fits. I’ve done 2 marathons so I know how to push through the wall. I just wonder if the wall is bigger after 57.2 miles of on the go. Thanks for the reply.
Charlie
I expect nutrition and especially hydration will be even more important the Florida heat. Thanks for the advise.
Charlie
Double your best oly time and add 30 minutes.
If the swim is your weakest link, then HIM will probably be your best race distance, assuming a physical affinity for endurance and the time and motivation to get the training done. The swim is disproportionately short in relation to your stronger legs, giving you plenty of time to make up for your swim deficiencies.
With a 2:27 Olympic time, again making an assumption that you are as fit for the half as you were for the Olympic, you should be well under 6 hours.
I have done a number Olympics in the 2:30-2:20 range with a PR of 2:19 and have gone sub-5 twice and get most of my halves done in 5:10-5:20.
Get the training in and you may surprise yourself. 
G
Here are my races last year, both first HIM and first OLY:
HIM 3/31/07 Total Time 5:09
OLY 9/9/07 Total Time 2:33
I was in better swimming shape for the HIM and better biking and running for the OLY. I would factor in how fast you can run a half marathon on its own. On 1/21/07 I ran a PR (not saying much) of 1:39. If you have a solid run I would think you would be in the low 5hr range for the HIM…
The swim is the weak link for me, too, so I place better relative to my age group at the half ironman distance.
With a 2:27 Olympic (way, way faster than mine!) you will go under 6 hours for sure assuming (a) you do the training and (b) the course is not outrageously hilly or hot.
Excellent to hear. I’ll keep my fingers crossed and get in two more long runs and two more long bikes before the HIM in 3 1/2 weeks.
Charlie
That would be awesome if I could go low 5’s. Beyond my expectation. We’ll see what the Florida heat does to me and how slow and fatigued I am swimming without a wetsuit.
Charlie
I don’t think the Florida HIM is known for having hills. Part of the reason I chose the course - the flattest of all the HIM races. I’ll just have to contend with the oppressive heat and humidity.
Charlie
What race are you doing? Florida 70.3? Is it not wetsuit legal?
G
It is legal, but only if the water temperatures are low enough and this time of year the lake at Disney is like bath water. By the way it is the Florida 70.3. My first at that distance and second triathlon.
Charlie