Friday, June 06, 2014

Race Report: Seoul Sinmun Marathon and Hangang Marathon

You can skip this post unless you care about running/exercise physiology/silly athletic endeavors.

Back in late February, I went snowboarding for the first time in four years. It was a truly awesome weekend. Aside from getting some great boarding in, my friend and I were welcomed with amazingly open arms by a ski/snowboard 모임 (like a club), and we ate, drank, and partied merrily into the wee hours with sixty total strangers. Honestly one of my favorite weekends in Korea.

Unfortunately, the second day of boarding, I sustained a bit of a setback. Before heading up the mountain, we bought a small flask-shaped beverage for "nourishment" in the cold. I put it in one of my many pockets, and on the way up the first gondola joked that I was going to fall on the bottle and crack my ribs. As if the Fates heard me calling, on the first run of the day, I took a really nasty, really hard fall on rock hard ice and landed directly on my rib cage (probably because I'm scared of breaking my wrists snowboarding and thus didn't try to break the fall with my arms). I missed the bottle, but still managed to crack a bunch of ribs. I knew nearly immediately that I had broken ribs, but I wasn't coughing up blood, and it only really hurt when I breathed, lifted my arms, or otherwise moved my torso, so I decided to keep boarding the rest of the day.

When I got home, I knew that my exercise plan was going to have to be modified. Since I realized I probably couldn't lift weights for around six weeks minimum, I decided that instead I was going to up my cardio a bit and train for a half marathon. I put together this whole nice spreadsheet, the plan being to train for a half marathon with no more than 20-25 miles of running per week, mostly aerobic but with one day of speed work per week, and incorporating lifting back into my schedule once the ribs were healed, lifting three times every eight days. The race I was targeting was on May 24th.

The best laid plans....

Things were going great - I did a 12 mile run on April 13th, but then over the next five weeks before the race (I had to switch to a different race on 5/17), my longest run was about 9.5 miles. Not for lack of effort - just on each of those long runs, stuff started hurting, and given that I'm rather conservative with these things, I listened to my body and stopped. Additionally, all long runs were done at Maffetone aerobic pace, with literally no time spent at race pace during the long runs.

Long story short, when race day came, I had not put in adequate mileage, but hoped my fitness would carry me through.

Race 1: Seoul Sinmun Marathon. Goal time: 1:45

Race day comes, and I boldly set my goal time based on the McMillan Race Predictor. Based on my 5k and 10k times, I was predicted to run about a 1:45 half, or approximately 8 min/mi (5 min/km). When I got to the race location, I already didn't feel great. My legs felt heavy, my heart rate was higher than normal (before even starting to run), but more than anything else, the weather was hot and humid, and I had done approximately zero training in warm weather. But I went out at race pace anyway, and after only 6 km or so, I got a stitch (side cramp). As there were 15 long km left, I knew I was in for a painful day. At 8 km, the leader and I crossed paths (it was a there-and-back course, which meant he had already run 13km - hard-core), and before the halfway point, I was already taking increasingly long walk breaks at the water stops in an attempt to get rid of the stitch. Didn't work. With about 5 or 6 km left, I had cramps on both sides, and had long since adjusted my goal to two hours. And then I remembered that the second to last half kilometer was straight uphill a steep exit ramp from an elevated highway. At the bottom, I looked at my watch and knew it was going to be close, but decided I was going to run up the hill whether it killed me or not. I could already see a long procession of people slumbering up the hill like the wandering mobs of walkers in The Walking Dead, so when I started passing them, it felt great! Then I looked down at my GPS watch, and it said I was moving at 12:30/mi pace. I felt like I was flying, so I figured it must have been an error, so I looked away for a minute, then back again and it was like 12:27. Ah well. It still felt good to run up that hill and pass everyone, and then I booked it to the finish and got in at 1:59:08. All in all, not bad for a first half marathon.

Lessons learned: If racing in hot weather, you should probably do some training in hot weather. If running a half marathon, you should probably be running more than 15-20 miles per week, and your long runs should probably be 16-18 miles, unless your goal is just to finish rather than to hit a specific goal time. I was clearly unprepared for the distance and the conditions, but my fitness did indeed carry me through to a respectable finish.

Race 2: Seoul Hangang Marathon. Goal time: 1:50-1:55

Two days after the Sinmun Marathon, I was feeling pretty good and was already back at the gym doing light recovery stuff. I started toying with the idea of doing one more race before packing it in for the summer, except it was going to be a 10k. I kept putting it off until Monday, when I looked at the forecast and saw abnormally low temperatures for Friday morning (race day). Stupidly, I decided to go all in and do another half marathon, since I was unhappy with the last one. I had only run outside once in the three weeks since the last one, and just for about 10k, so I reasoned that I had actually "tapered" quite nicely for this race. Plus I've been trying to increase my sauna time after workouts recently, so I hoped I had also increased my heat tolerance.

I also decided to do a little science experiment. I have trouble with the early morning races, because I usually don't eat breakfast, but on race day you're "supposed" to eat beforehand, so I've been forcing myself to get up insanely early to eat something and hopefully have it digested before the race. But since I'm not used to eating that early, all it does is give me stomach issues. So this time, I decided I was going to skip food and just drink a bunch of Pocari Sweat (a not-too-sweet electrolyte drink) a few hours before the race. Except yesterday, when I did a dress rehearsal with the Pocari Sweat first thing in the morning, I realized that it also wasn't particularly agreeable to me - it tastes great when you're thirsty after a workout, but no good just out of bed. Thus began the great Fasted Half Marathon Experiment of 2014. I wondered - is it possible to race a half marathon in the fasted state? You're not supposed to do anything new on race day, and since I usually skip breakfast, according to that logic, I should also race fasted.

Quick background on fasting and fuel for exercise. Fuel for exercise comes from three places: ATP (used primarily for short burst high-intensity activities like 15 second sprints), glycogen (used primarily for activities in the "anaerobic zone" - like running fast enough that you're breathing hard), and fat (used for low-intensity activities, primarily in the "aerobic zone"). Contrary to popular belief, your body always uses a mix of the three - it doesn't just switch from one to the other like switching from gas to electric on a Chevy Volt. For a half marathon, glycogen and fat are clearly the main fuel sources, and out of these, glycogen is the more important one, simply because it's resource-limited: that is, you have at least 50,000 calories worth of fat on you even if you're lean, but you can only store a small amount of glycogen in your body - about 100g or so in your liver, and 400g or so in your skeletal muscles. When you hit the proverbial "wall", it means that your muscle glycogen has run out. I had always heard that "fasting depletes your glycogen stores", but it turns out that's not entirely right. Fasting depletes your liver glycogen stores, because your liver turns the glycogen back into glucose during fasting in order to keep your blood sugar stable. But muscle glycogen is only depleted when you actually use the muscles. Evolutionarily, this makes perfect sense - you want to keep the sugar in the muscles during a fast so you're strong enough to go find food in some short, intense bouts. So anyway, I reasoned that I should have just about enough glycogen in my muscles in order to finish the half marathon, although I'm not sure how much glycogen is stored in muscles used by running (running is actually a whole body activity), nor how fast it decreases during sub-lactate threshold pace, which is where I was running the half marathon. But I figured, worse comes to worse, I deplete all my glycogen, which will be interesting to experience, and I finish the rest on fat after passing the metaphorical "wall". (Note: The ratio of fat to glycogen used at a given intensity is strongly affected by your level of conditioning - better conditioned people tend to conserve glycogen during exercise, whereas less-trained people burn through their glycogen stores at a quicker rate. Additionally, the amount of glycogen that your muscles can store is affected both by your training, whether or not you fast, and your nutrition in the days leading up to the race.)

So, about 13 hours after my last bite of food, the race began. Of course, the weather forecast from earlier in the week was totally off, and it was hot from the beginning - just under 80 degrees Fahrenheit, with a "Real Feel" of 88. I forced myself to run based on my heart rate for the first half, often slowing down in order to bring my heart rate back down to my target range. The first half was quite easy, albeit hot - I hit every water stop, drinking one cup and dumping one over my head. I started to pick it up effort-wise in the second half, although I needed a large negative split to hit the 1:50 goal time (my first half was just over 57 minutes). With about 5-6 km left, I felt pretty good and decided to kick to the end. Of course, I ran my fastest km split, and then promptly had a stitch, which forced me to slow down for the next three km. I pushed the last km to the finish, and came in at 01:54:30.68. Not bad for a fasted race in the heat!

Lessons learned: If you haven't put in the necessary mileage for a half marathon, running once in three weeks and then doing another half marathon in hotter temperatures will not make it any easier. However, it is indeed possible to run and finish a half marathon while in the fasted state. That being said, I wouldn't recommend it to anybody - nearly all research points to better performance with a pre-race meal and fuel during the race. Anyway, I'm done with half marathons until I'm actually properly trained for them. Really this time. ;)

Alrighty, if you made it this far, you are truly an exercise/health nerd. Congrats, and stay tuned for my upcoming one year update on re-engineering my health!

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