So, only one week and one day later than planned, Project 80 launches today.
Project 80 is simple. I need to weight 80kg or less by the time I get to run London Marathon. Ideally, it could do with being closer to 75kg I think, but 80 is probably more realistic.
Before we get into why this is important, I am aware that some of you cannot figure out kilograms (kg) and may prefer weight measurements to be in stone and pounds (st, lbs) or just pounds (lbs). I will do my best to do the relevant conversions for you as we go though this.
So, a long time ago I wrote a blog post explaining why weight is particularly important in running. At the time I was training for a 100 mile ultra marathon (which I never even made the start line of) but if you want to read this you can find it here. Time to Address the Elephant in the Room
The basic premise is this.
- When you run the ground force through your joints is 2 – 2.9 times your body weight each time your foot hits the ground
- A marathon is 42,000 metres. Assuming I travel a metre per stride, that is 42,000 foot strikes
- If I weight 100kg (15st 10lbs, 220lbs) then this is 100 x 2.5 (if we take the average from the first point) x 42,000 which equals 10,500,000kg of force my legs have to absorb over a marathon distance.
- If I weigh 80 kg (12st 8lbs, 176lbs) this number reduces to 8,400,000kg of force, a reduction of 2.1 million kg of force my body has to absorb
- The largest bull elephants weigh about 6000kg, so the reduction in impact force is around 350 elephants worth. Thats quite a lot.
Then things get even more interesting. According to a podcast I listened to a long time ago (which I now cannot find to reference) athetic performance increases roughly 5% for every 10% of bodyweight you drop, assuming that you only drop fat and maintain muscle. Now bearing in mind I want to drop about 20-25% bodyweight (I currently weight more than 100kg (220lbs or 15st 10lbs) I could be looking at a performance increase of 10% or more. This would mean that my current marathon speed of around 12.5 minute miles would improve to possibly sub 11 minute miles, which would improve my marathon finish time from 5hrs 30 minutes to around 4hrs 48 minutes.
Now all of the above is just based on weight alone. It does not factor in improvements in fitness that can be made from training. It is only taking into account my current level of fitness and my current weight vs my ideal racing weight. So if I get the training right and the weight loss right I could be closing in on 4hr 30min marathon, or perhaps less.
Whilst marathon running is not all about finishing times, believe me being out there for an hour less is a good thing. Marathons are hard. Really hard. You usually feel OK up to around mile 18-20, then you face 6-8 miles of pain and suffering to get over the line. If that pain and suffering can last a bit less time that can only be a good thing.
All things considered it is a good idea to weigh less than I do when running. Quite a lot less in fact. So, for the 133rd time of trying, I am going to have to lose weight. Something that is relatively easy to do in your 20’s, trickier in your 30’s and very hard to do in your 40’s. Combined with the fact that endurance exercise is not actually that good for weight loss (I will blog about this another time) and the fact that too much training tends to break my body anyway, basically I am just going to have to eat a lot less.
I really like food though. That is how I got into this position in the first place 🙂
Then again, if White Goodman can succeed on his weight loss journey and almost lead the Cobras to victory against Honest Joes in the American Dodgeball Association of America International Dodgeball Competition then I am sure I can do the same, and run London at a weight substantially less than I am right now.
So off we go. Not only do I need to train hard and rest and recover, but I will be needing to do this on a calorie deficit. Should be fun.
Next post will be about running and not about being overweight, I promise.
To track Project 80 and see how well (or not) I am getting on please use the Project 80 page