Sunday, 20 January 2013

Carbo depletion run

Like Sir Dave Brailsford, I am keen in looking for some marginal gains. I neither want to or have the time to (or the body to!) make dramatic changes to my training and racing. The bottom line is; if it aint broke, don't fix it. I am, however, keen to make some tweeks to my training to see if I can lift my ultra performances to the next level, whatever that level may be.

Having done some reading around, I am keen to add a few more ultra training runs to my schedule (rather than the one per month I did last year), I also want to do a few back to back big days out, just to simulate the latter stages of a long race.

I think I have become a little bit more streetwise (trailwise) with regard to nutrition during long races and particularly the recognition that I am mostly burning fats, not carbohydrates. I have read of a number of ultra runners who include carbohydrate starvation (carbo bleed) sessions in their training so I thought I would give it a go.

The basics are that you miss breakfast and do not take any food on during a run of somewhere between 2 and 3 hours. After the 2 hour point, once you have used up your muscle glycogen stores, your body has no choice other than to start metabolising fats, as you would in an ultra race. Your body hopefully becomes more economical at doing this. It is often tough going during the final stages of a bleed run, but I thought the time had come to give it a go.

This has been a medium week of training (5 sessions for about 50 miles) and I took yesterday off so I was ready to give this a proper go. Not having breakfast is tough; a mug of black coffee just doesn't hit the mark, but I headed out the door at about 9am, looking to do about 2:30 hours just to dip my toes in the water of a bleed run.

I headed round Derwentwater, down to Grange, along to Rossthwaite and made the climb over into Watendlath. It was surprisingly warm, certainly above zero and I felt quite good, without ever really pushing the pace. I was very concious of the thought that after 2 hours this might get tough and it seemed I was just killing time until this point.

It was somewhere after Watendlath Tarn that I started to get a bit tired, certainly not knackered or in any distress, but more tired than I would expect after just 2 hours of running. I kept the pace going but had to work harder, so I felt that it was a good workout.

I did find it nice to not have to worry about getting gels/food in at the correct times; I just ran and had a drink of water/electrolyte when I felt like it. Simples!

I was absolutely Hank Marvin when I got back to the house, but pleased to come through my first carbo starved run and will give it another go in a months time.


fell running guide said...

Dave, interesting stuff - is the idea that the body replenishes the fat stores between bleed runs? There must be a limited supply of fat to utilise, especially if you already have a low % body fat?

Debs M-C said...

Interested to see how you get on Dave. I've been working on this quite a lot since Autumn. It gets better!