Tuesday, 28 January 2014

Hitting the wall/ bonking/ whatever you like to call it

Monday 20th Jan:         10:00 miles run, time 1.32.06, 850 kcal, 9:12 min/miles
                                        2 x 3.3 mile walk, 560 kcal
Tuesday 21st Jan:         2 x 4 mile walk, 672 kcal
Wednesday 22nd Jan: 5 mile run, 425 kcal
                                        2 x 3.3 mile walk, 560 kcal
Thursday 23rd Jan:       2 x 3.3 mile walk, 560 kcal
Friday 24th Jan:            2 miles walk, 168 kcal
Saturday 25th Jan:       3.12 miles run, time 25:01:30, 265 kcal, 7:59 min/miles
Sunday 26th Jan:         Rest

Totals: 47.9 miles, 4060 kcal

Not much time to run last week with other things going on. Pleased to still nearly make 50 miles with the walking.

Feeling good for increasing my mileage, not really noticed being more tired and no injuries.
Now things are more back to normal in other parts of life, I’m planning to switch most of the walking miles to running. Am still going to try to keep doing some walking though, as I know I will have to walk a good portion of the race, and good to keep the walking muscles going too.
  
Have been feeling really weird on a few of my runs lately, it feels like I’ve got low sugar I think - I come over feeling really cold but sweaty (nice), I get a weird feeling about where I think my stomach is, kind of it actually feels empty, if that can happen, and I feel sick and like my legs are heavy and tired and I keep tripping up, and can think even less well than usual. Fair enough if I’ve run for a couple of hours and that happens, but it’s been happening after only 2 or 3 miles and on my walks too, but I noticed that it’s only ever been happening when I do training in the evening, not in the morning. So that’s kind of why I looked at my calories burned last week in the schedule above. I guess since my last marathon in November I’ve kept running regularly, but not very far so I was probably only doing about 30 miles a week, and now I’m doing 50. And I’ve only noticed feeling like this when I’m running during the last couple of weeks, so I guess that matches the increased miles. So I don’t get why it’s happening some times and not others, and why it would happen so early on in a run, especially if I’ve had a snack before going out, so I figured I should try to figure it out....

This is what I got distracted about before actually finding an answer to my question:  Bonking seems to be a big deal for ultra marathoners. Yes. Of course, I was intrigued.......

It’s actually probably less exciting than it initially sounds, Bonking, apparently, seems to be another name for the ‘hitting the wall’ that everyone talks about in the marathon - when your glycogen stores in your liver and muscles get used up, so your body doesn't have any fuel left to get you round the last few miles. This article is really interesting, it talks about the different types of ‘bonk’ you may experience on your run, and how to de-bonk yourself:

Also really interesting (for me at least, I appreciate this is entering into geek territory, so permission to switch off now if biochemistry doesn't float your boat) is that I have been learning about how your body handles the different macronutrients at uni recently. Carbohydrates have attracted a lot of interest lately, especially sugar, and especially fructose sugar. Our bodies seem able to use glucose much more efficiently than they can use fructose – when fructose is eaten, it has to go to the liver for some processing before our bodies can use it for anything. In contrast, glucose can go directly to our muscles and be used for fuel straight away, so this is why most running nutrition products contain glucose as their carbohydrate, because it gets straight to where it’s needed. However, your brain needs glucose to work as well as your muscles needing it. When the glucose has got into your muscles, it can’t come back out again, so the brain can’t use that. Your liver can store at little glucose as glycogen, but by this point in your run you've used that up as well, and if you’re only eating glucose at this point, this isn't going to your liver, it’s going straight to your muscles once absorbed, so your liver glycogen is low and your brains glucose source is pretty much empty. So that’s when you get the mental problems in running (apart from doing it in the first place) and also your brain senses glucose is in short supply so starts to shut down other systems in your body too, so nothing is working properly. So, the recommended solution in the above article is to make sure you’re hydrated and glycogen stores replenished at breakfast before the run, then after running for several hours start including foods that contain sugars as well as glucose, so that they have to go to your liver first of all, and our liver is thinking of your brain, and will send supplies to it.

Science over. You may pay attention again.

Some other things I picked up:
·     - Ultra marathonning is a deficit sport! Your body can only absorb about 240 kcal per hour, but you burn about 100 kcal/mile, so maybe 500 kcal/ hour if you do 5 miles per hour. So you cannot replace all you use during the run, so you will end up less than you were at the start! :-( I din't know you could only absorb that much.  
·     - When you’re running for long time at a low intensity, your body can pretty much use anything for fuel, which is different from what you read when doing a marathon when the focus is on carbohydrates. So, initially carbohydrates may be best, but after while you may like to start including some protein, and fat can be useful too. This article is really interesting: http://www.ultrarunning.com/features/the-last-article-youll-ever-need-to-read-about-what-to-eat-during-an-ultramarathon/  

c    So, till next time.....








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