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Tuesday, February 26, 2008

Fighting the Bonk

So I've done some research to figure out what went wrong during the 1/2 marathon.

"Bonking" seems to mean different things to different people, but what I clearly suffered from is a depletion of glycogen stores.

During exercise, your body uses two sources of fuel: glycogen and fat.

Fat: If you're like me, you have no shortage of fat! Many many thousands of calories of fat. But while fat contributes energy to your effort, it can't sustain intensity.

Glycogen: This is the gunpowder, the stuff your body needs to sustain an intense effort. Your body can store around 2000 calories this way, if you've done everything right to maximize your stores.

You burn the same number of calories running no matter what the intensity (more or less). But what changes is the type of calorie you're burning.

At low intensity, you burn more fat per kilometer. At high intensity, you burn more glycogen.

So despite my being able to do a 24k run a few weeks ago, in the 21.1K half marathon I was bagged by 15K. This was clearly down to the intensity. 24K @ 6:00/km relies less on glycogen than 21.1K @ 5:24/km.


1) Carbo-load. I thought I had done this, I ate a lot of complex carbs the day before the race. Whole wheat crackers, whole wheat spaghetti, etc. In the morning I woke up and had Mini Wheat cereal, followed by multigrain toast and a little bit of egg, and some milk, and Coke... right before the run I ate a banana and was drinking Gatorade.

But the race was right at my normal lunch time, and I think I may have (unbelievably) under-ate.

2) Eat during the run. I thought the Gatorade would be sufficient, but it wasn't. I splashed more on my shirt than I got into my mouth most times - I need to practice drinking from a cup while running! I really should have gone with some gels, I forgot to buy some and was unprepared. Next time I'll target 250 calories an hour during the run.

3) Lose weight. I'm a big guy, around 190lbs, and carrying all that weight around 21.1k takes energy. Using the formula :

Calories burned = 0.4785 * weight in pounds * kilometers run

I discover that each pound of weight takes 10 calories to move 21.1K. Dropping 10 pounds would save 200 badly needed calories over a full marathon... mostly on the glycogen side.

4) Slow down. I'm not sure this is an option, because other than this bonking thing I felt the pace was good. If I had the energy I should have been able to go faster, it was in me, just ran out of gas.

What really burns me is that I knew about the importance of all of this... I did a century ride on my bike, over 5 hours of riding. Fueling up and staying fueled up was critical! I just didn't think 2 hours of running would be so hard, but I underestimated intensity.

Sunday, February 24, 2008

Race Report: Peterborough Half Marathon

2007 time: 2:07
Goal: 1:54 or less
Actual time: 1:53:55

Cut it a little fine... :)

Weather: near perfect. Around 0. A little windy, but nothing dramatic.

First half of the race felt great, went well. I found a group that was maintaining a very steady 5:20/km and stuck with them for the first 10K or so. That put me in really good shape.

Then at the halfway mark I accidentally reset my watch! Enter the darkness - I had no idea whether I was on pace or not. The 1:55 pace bunny passed me, I thought I was slower than 1:55... I tried desperately to keep up with him to no avail. Turns out he finished ahead of me, his time must have been 1:53 or faster! Grumble! He had me pushing faster than I needed to be, which shouldn't have made a huge difference, but didn't help any.

At 12K I began to suffer... I was in full bonk mode from 15K on, maybe even sooner. I just had nothing, I was desperately trying to hit my 5:24's but it was hit and miss. Some kilometers were right on, some were over 5:40. By the end I was totally sapped for energy and pace, I almost passed out... I just had nothing left in the tank.

I need to figure out why I bonked. Could be I didn't get enough calories during the race, had some problems getting the Gatorade into my mouth. :) Silly cups. Could have used gels, might have helped.

All in all, a pretty good outing... something to build and learn from, and a goal achieved. :)

Race Day!

Just getting ready for the Peterborough 1/2 marathon.

Temperature looks perfect - 0 degrees and sunny, not too much wind, can't ask for more in February.

I still have 5 hours before the run, which means I need to eat something more substantive than I'd like. Just polished off a big bowl of cereal, after this I'll keep it pretty light and snacky. Don't want too much food sloshing around in my stomach.

Had some knee pain this week, so I'm a little concerned with that. I've had ITBS in the past, this seems related. Got out for a 5K run Friday and all was OK, so might not be worth worrying too much about.

I'll post with my results in a few hours! :)

Wednesday, February 20, 2008

Good-bye Duke's Cycle...

A very sad day for Toronto's cycling community, as Duke's Cycle on Queen burned to the ground.

I bought a bike there last year, the staff were great, lots of good knowledgable people. It has been there for four generations, since 1914!

The 4th picture down shows Duke's burning... the 5th shows the building gone.

Hopefully they can rebuild their business and be back someday.

Sunday, February 17, 2008

Running at a Specific Pace... Mission Impossible?

With one week to go before my 1/2 marathon, I wanted to be sure I could maintain my target pace of 5:24/km over a longer distance. Like most, I run my long distances sllloooooowwwwlly.... so it's a check of where I'm at.

I decided to do my 14K run at 1/2 marathon pace.

The good news is that I did it, quite easily in fact. I finished it 2 minutes quicker than intended, with a pace around 5:15/km.

What concerned me was that I had a very hard time finding 5:24 and sticking to it.

I was all over the place:


I always felt like I was going too slow, and when I'd try to back off I really would go to slow! Some of it is attributable to downhills and uphills, but mostly it was an inability to find the right pace.

I'm not quite so worried for the event, I'm sure there will be people in groups settling in to pretty consistent paces that I can hang with. If I find myself passing people suddenly or being passed, then I'll assume that I'm not being steady.

Friday, February 15, 2008

Peterborough 1/2 marathon - 1 week to go!

I keep forgetting what I decide for my target pace, so I'll put it here to keep me honest and help me remember.

If the weather is good and the surface is bare:

Pace: 5:24/km
Finishing time: 1:54 or less

Last year's time (after only about 4 months of running): 2:07

According to the McMillan Running Calculator :

... running a 1/2 marathon at 5:24 is "equivalent performance" to a 4:00 marathon. Since this is my target time for my May marathon, it makes sense to ensure I can perform at this level. It is also consistent with my 5K performance.

I'm comfortable with the distance, I ran a 24K last week. But 5:24 seems really fast for 2 hours of running! I've done that pace over 10K without too much trouble, but never for anything longer than that.

Comments appreciated as always! :)

Sunday, February 10, 2008

Running in the Sleet

I had a long run scheduled for this weekend, 24K, my longest ever.

Saturday forecast: snow/rain, +2C
Sunday forecast: -7C with strong winds

I chose Saturday.

Spending 2 1/2 hours wet at around freezing doesn't sound like fun, and without the great advice I got from my experience earlier in the week I wouldn't have tried it!


- Head condom. OK, that's not what it's really called. Kind of like a spandex head thing, sheds moisture nicely, covers ears. I got it for biking (under helmet) but works great for running.

Top Layers: (this is where I changed things up)

- Nike base layer, a very thin shirt that does a fantastic job wicking moisture away from the body.
- Long-sleeved cycling jersey - a bit thicker than I would normally wear at that temperature, but ended up being perfect.
- Running jacket, a thin not-water-proof jacket.


- regular running tights, my loose ones. They're not super tight, which leaves some air space, I like them better than the tight ones


- Wright double-layer socks - thin and fantastic
- Running shoes - my usual ASICS


Supreme comfort!

The only thing that sucked was splashing through puddles, soaking my feet with ice-cold water... but that was always temporary, within a dozen or so steps the water was gone and my feet were warm again. Not dry - never dry! - but warm. And with the thin double-layer socks even the wetness didn't bother me. The layers make a huge difference, no blisters.

As an aside - 24K is a very long distance for me, especially in sub-optimal conditions. Fortunately I didn't have any knee problems, it went great. But I was definitely pushing my limits, which I guess is the point!

Next few weeks:

Peterborough 1/2 marathon (21.1K)

Can't wait!

Wednesday, February 6, 2008

Running in the Rain

Running in rain when it's +20C or more = refreshing!

Running in rain when it's +10C = mildly uncomfortable...

Running in rain when it's +2C = naaaaasty...

It wasn't intentional, I ran to the rec center where my swimming lessons are in the dry. But when I got out, it was pouring.

The worst was that my light running jacket got soaked, then it stuck to my skin. This allowed the cold to get right through to my arms. I think if I had a layer underneath - even a light one - it wouldn't have been as bad.

On the bright side, I had thin socks, so they didn't soak up water like some crappy sports socks can. Feet were fine.

Probably good experience, just a matter of time before I line up for a race in a downpour.

Sunday, February 3, 2008

Longest run ever, welcome back ITBS!

I did my 22K LSD yesterday, which was 900m longer than my previous longest distance, the 1/2 marathon.

I had plenty of energy, my muscles were working great, I was very encouraged... until about 17K.

Then my IT band started to bug me. I stretched, tried to keep going, but it wouldn't subside for me. Finally I hiked my running tights up above my knee, letting the -2C air get to it. Presto! Pain began to subside. I was able to get through the last 5k with some additional stretching and only minor pain.

When I got home, I plunged my leg into the fresh snow and packed snow on top of it. That felt great. :) Sat there for about 3 minutes, which got a few funny looks from people passing by. Stretched and went back to icing it, it feels pretty OK this morning. I'll take today off, then do a recovery run Monday and see where I'm at.

My long run plans for the next few weeks:

- 24K
- 19K
- Peterborough 1/2 marathon (21.1K) - at my planned marathon pace (5:30-5:40/km)
- 24K - back to building for the full marathon
- 26K
- 28K
- 22K
- Around the Bay 30K - at my LSD pace (6:00-6:20/km)

If I'm still having ITBS trouble, I'll push the full marathon back until the fall and do some 1/2 marathons instead. It will really come down to that critical 24-26-28 string of LSDs.