Running on Empty

I like to think I know my body very well indeed and after running 4000 miles in 3 years, I also like to think I know a great deal about sports nutrion in general. Now I wanted some answers about nutrition and how it affected me personally.

As an experiment, in the past 3 weeks I wanted to try to run my normal high mileage on zero fuel intake i.e. no carbs, until eventually my tanks were empty to see how it affected my heart rate, performance and recovery. 
I thought of this experiment as a bit like running a petrol car on the wrong fuel and we now what dramatic affects (and consequences) that would have. So my diet for 3 weeks was replaced with food from the pyramid (right).

First, for anyone who does not fully understand or appreciate carbohyrates (carbs), they are not all created equal.
Some carbs fall into the 'complex' category (low G.I.) and other into the 'simple' category (high G.I.) which are mainly sugary/sweet foods. All carbs will help with an energy boost but the problem with high G.I. foods is they raise the blood sugars very quickly, thus giving 'energy spikes', which then results in blood sugars plummeting to lower levels then previous (around 30 mins), which leaves you feeling tired and exhausted. The body does not benefit nutritionally from simple carbs.
For this reason I have always avoided them with a the exception of chocolate and a Snickers bar in particular because it has a low G.I. because of the nuts =0)

Complex carbs delivers energy slowly and increases endurance & performance.
A few (but no means all) foods rich in 'complex carbohydrates' and often prefered by runners are:
# whole grain breads
# whole grain rice
# whole wheat pastas
# whole bran and grain cereals
#whole grain flour
# potatoes


Running on empty:
Since I'd completed my 2,000 mile challenge last year and I was no longer running 50 miles every single week, i'd began to gain a few pounds on the scales. So I started swimming more, joined spinning classes, and would even run 5 miles to the pool, then swim 1 mile and run back again. But I still couldn't shift the excess weight.
So this experiment was initially to lose 4lbs, and began on Wednesday 23rd June with NO MORE CARBS for 3 weeks.

Week1 25 miles slow with friends and a 10 miles run on my own, which included a 5 mile run to pool with a 1 mile swim and a 5 mile run back. I didn't really notice any change in anything at all, weight, stamina, performance or endurance.

Week2 only ran 12 miles slow with friends and one 5k speed run on my own. I don't normally run less than 6 miles as its over too quickly, but this run was hard, which I initally put down to the heat. Looking back, I actually stayed in bed twice that week, when I should have been running. I have never done that before. Didn't swim either. Was told by Jules that I was looking tired. Also began to slur my words after just 2 glasses of wine. Feeling tired and found I could not speed run for more that a couple of kilometers before walking. Heart rate raised to 170 for moderate exercise.

Week3 ducked out of running my usual 6 mile run and stayed in bed. Friend called me short notice to run 6 miles next morning and I agreed to run with him. He was slow as usual and felt good to me. Then another friend called me for a 6 miler next morning. We met up and ended up doing 11 miles which almost killed me and she beat me on a sprint finish, which she'd never done before. I slept for 2 hours in the afternoon.

My body was now completely carb deficient and I felt fatigued, but I was STILL running. My heart rate was raised, my legs were weak but more importantly my desire to run was dimished.

Carb Loading:
To most runners 'carb loading' means stuffing your face with pasta, bread, rice, potatoes just before a race or hard training run. Actually 'loading' only really means an ADDITIONAL 30/40 grams of carbs for 2 days before an event.

So now I was going to 'carb load' on top of an empty tank to see what affect it had.
Friday - 30g carb load - no running
Saturday - 30g carb load - no running
Sunday - 7 mile run + 30g carb load
Monday - 6 mile speed run

Friday, I instantly noticed my energy levels increase and was twitching to run. I didn't.
Saturday was more of the same.
Sunday, I eagerly set off. A little too quickly really, and I felt the discomfort hit me at only 3 miles and struggled to get the whole 7 miles finished.
Monday, I was cautious after Sundays disappointing effort. But my watch told me I was running faster and stronger than Sunday. I finished the speed run with a lower heart rate, and feeling great. Averaging 8 mins per mile, I felt as if I could have kept running.  

Lessons learned:
# I have enough carbs in my body to sustain normal training for 1 week.
# I can run and train on empty but only because I am determined.
# Even I can become mentally fatiqued and apathetic.
# Even when wanting to lose a few pounds, it's still best to have a trickle of complex carbs.
# It only take 2 days to get the carbs back into balance.
# I can pre race 'carb load' even starting from an empty tank.
# I can get back to peak performance in only 2 days.
# Zero carbs makes me tetchy and short tempered
# I got drunk very quickly.
# I did lose 4lbs

Remember, this was MY experiment for me to discover new things about my running, training, carbs & nutrition. Also how my mind and body would cope under such condition. Please don't try this unless you are an experienced runner and understand your objectives.

G.I. is Glycaemic Index which is the measurement of how fast your body burns your food to use as fuel.
http://en.wikipedia.org/wiki/Glycemic_index

Please leave a comment or a rating.
Also read Keaths 'comment' at the end.

Stephen



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