November 3, 2010

I am Finally getting around to making an entry about the Saturday Oct. 30th 12 Hour Mountain Bike Race Simulation Field Study I was the subject for.  An event which some friends named the "1st Annual Tony Cervati Invitational Classic".  I guess you need to be name Tony Cervati to race in it?  Too bad there was no "prizes"....

Ride Hours: 11:47

Insulin Delivery Summary:
Daily Total: 25.98 units
Meal: 6.50u
Corr: 2.50u
Basal: 16.98u

Daily Carb Intake Bolused For: 86g


The "race" took place in Chapel Hill, NC at the Carolina North Trail system. It was done in support of Chris Newport's Master's Thesis which is focusing on Type 1 Diabetic Endurance Athletic Nutrition.  Chris has been guiding me for over a year now, and is THE key factor in getting my on the bike nutriton nailed down.

We tracked my diet and insulin usage for 48 hours prior through 48 hours post event.  During the field study, which ran from 9am-9pm, we employed technology including the Abbott Navigator CGM and Cyclops PowerTap hub to monitor, in high detail, calorie intake, wattage, cadence, speed, miles, vertical feet, temp, humitidy, blood glucose, heart rate, core temp, weight, hydration, and electorlyte levels.

These measurements will give a pretty good picture of exactly how my body is working at any given point during a long day in the saddle.  For me, this is absolutely invaluable as I prepare to race the 2800 mile Tour Divide in June.  Also, although I have been working on the TD attempt in one capacity or another for 18 months, I consider this study to be the first official step towards Banff Canada.

I was VERY nervous about the ride, more so than a race, given the fact I felt Chris had been working through 2 years of school to get to this day.  I went to bed Friday night thinking "Don't wake up low.. Don't wake up low...", so much so that I under bolused for a bedtime snack on purpose.

I was WIDE awake at 03:40 running a BG of 193.  I took a breath and told myself to just do what I always do and it will work out.  I bolused for this slight high, but never did get back to sleep.

At 06:53 my BG was a picture perfect 81, and the Navigator sensor I had inserted at 21:15 last night was soon ready for its first calibration.  BG at a 78 at 07:11.

I ate breakfast and was monitoring my BG tightly.  At 07:25 I was a 76.  I set my target BG in my insulin pump to a 150 (instead of its normal 100) at this time, and, since I was so nervous, set my pre-ride temp basal at a 60% reduction.  A little early, but I really wanted to be good to go by 09:00.

I got the site at the trail head a litte after 08:10, and got the camp site setup just as I would for a normal race day.  Going to ride for 90 minute laps on the various trails, and then check in to grab the data.  The temps were a little on the chilly side Saturday morning (high 40s), but the weather for the day could not have been more perfect!


The most humorous part of the data collection was the Specific Gravity of Urine test.  I mean I have been friends with Chris and her husband Jay for a long time, but I never handed her a urine specimin before.  In the doctor's off PLENTY of times, but this just seemed a little... um.... different.  We all laughed about it for a while, but it did just become part of the groove after 5, or 6, or 7 hours.  :)

I was VERY fortunate to have some great friends come out and ride with me for the majority of the day.  A big thanks to Jay, Pryde, and George for riding with me and keeping it fun.  These dudes are mega fast and had me on my toes and hustling all day long.  THANKS!!!


I tried to stay on the usual 20oz of water mixed with Maltodextrose and Nuun every hour, and 20-40g of Carbs total per hour.  I did fall behind on the hydration early and then later in day, but all in all it worked out great!

BGs rocked all day.  I had the low alarm on the Nav set at 60, and the high alarm set to 180.  Average was 124, with no reading outside of target during the 12 hour ride.



Only issue I had was a mistake I made around 13:30.  I had set a 60% reduction for 6 hours at 7:30.  Since I normally don't go to a temp basal until 60 minutes before ride start, I had missed the switch to a 70% reduction at 13:30.  I thought I had until 14;00.  So for about 30 minutes there, I was running a full on basal rate 4.5hrs into pedaling. I set the temp basal of 70% reduction right after 14:00.  If you take a look at the image above your can see how this made a dip in the BGs begining right around the 13:30 time frame.   Exercise induced insulin sensitivity right there.

I was able to catch it with a few extra carbs, and you can also see on the graph that I over compensated a touch.  Not horrid, and better safe then sorry, but still.  A smidge too much.


The rest of the ride went without incident and I was SO STOKED at the end of the ride at 20:47 with a blood glucose of 111.  I was tweeted "Diabetes - who's your DADDY?!?!?".  A great day in the saddle!!

Once I stopped I immediately set my basal rate back to normal, and bolused 4.5u to try and head off the normal post ride BG spike.  Wasn't sure if that was going to be enough, but it worked out well.

Some of the first stats about the ride is that I covered about 86 miles todal, with 72 miles coming on single track.  Burned 10,800 calories, and went over 5300ft in vertical.  More data will follow as it becomes available.


Post "race" my BGs were 95 at 23:15, 111 at 23:22, and then 133 at midnight when I went to bed.  No correction for any of these of course.

As is usual I set a post ride over nite temp basal of 65% as active for 7 hours and hit the hay.

Today turned out great!!  I can't wait to see what we are able to learn, and then figure out how to apply it to racing the Tour Divide.