Quite a common topic for discussion is how and when to fuel when training. I regularly get asked for advice from runners especially on fuelling half marathon or marathon distance races and a the risk of being non-committal “it all depends on you, your training, your goals & your body” is the regular answer.
Look nutrition and metabolism, is a complex area and almost all of it depends on you and your training. In that I am not mistaken.
There is so much chatter (and I’m adding to it) about nutrition do’s and don’ts that it is ridiculously confusing.
It shouldn’t be and is quite simple really.
Without going into a whole complex area (and tripping myself up over technicalities!) about which many, many books have been written the best example is for me to impart the advice I have learned myself and from others experiences.
I hear gels make you sick / run through you…
This line is often coming from someone who is ‘ready’ to try their first gels but has received advice from someone who has had a bad experience with gels because of…well.. bad advice they in turn have been given.
If you leave it too late to take a gel the likelihood is you will throw it up. At high intensities blood is pushed or ‘shunted’ from non-essential body functions (like digestion) to the working muscles to maintain as much oxygenated blood flow as possible. Basically the digestive system goes into standby (why most people don’t feel like eating after a workout) and the gel sits in your tummy.
Ingest too many, as you feel your body running out of fuel you panic and throw more gels into yourself and you are going to be looking for a bush as the body voids itself.
Simple rule is timing – more shortly.
How many do I need to take?
Whether it is 1 or 20 depends on you.
Here’s my thoughts….
Generally the average person of average training is reckoned to be capable of storing enough easily accessible fuel for roughly 2-2.5 hours of moderate intensity exercise. After that your blood sugar and intramuscular glycogen are depleted and you start to ‘bonk’. It is now likely too late to take gels and you end up in ‘limp home’ mode.
If this is you, you need to be taking extra fuel on board earlier rather than later.
Think of it as setting out on a car journey of 500miles with a fuel tank range of 100miles. You can drive 400miles and take a chance that there is a garage but possibly end up having to walk for 100miles as you have drained the fuel tank and the lines need bleeding; or, you can top up your tank at 50miles, 100miles and 200miles ensuring you have enough fuel for the journey with reserve.
There are people like Barry Murray who writes extensively about sports nutrition and to be honest his self experimentation is well worth reading. It is anedotal but based in reality and I would personally follow as many of his concepts as possible while also tailoring to suit my own needs. As he says himself (re)-adapting the body to being an efficient fat burning machine can take years of adjustment and tinkering with diet to find what works for each individual.
1kg of body fat contains approx 7,500-7,700 kcal of (clean) usable energy which is roughly twice as much energy pound for pound with carbohydrate. So if you adapted to fat burning (or sourcing energy from body fat) you could technically fuel a double marathon with 1kg of body fat!!
However it is tricky dialling back training to build ’empty’ miles and tinker with diet to find what suits you best so most people stick with their normal (slightly healthier than norm) diet and depend on ‘artificial’ fuel in the form of bars, gels and jellies to get them through their training.
What I tend to do is a balance. I do plenty of long easy distance running and biking with little or no fuelling or with fluids. (I started this process a while back) A recent 8.5 hour bike spin saw me consume less than 1100kcal and 1.5 ltr of fluid at low intensity over 185km. I find the best for me is low GI gels (Agave #9) and protein based solids where possible so blood sugars are not spikes leading to a crash.
When racing I might use a light sports drink like Tailwind beforehand and fuel with Agave #9. I used x3 gels in the half at Connemarathon.
Key is, in my opinion, to get that extra fuel in earlier that you think you need it in order to have it when you require it. You also need to experiment to find out which works best for you and do plenty of reading about the techniques that Barry advocates.
A simple way to think of it is that you are not fuelling for the workout or race that you are doing per se but more to consider that you are fuelling now for how you want to workout tomorrow.
If you have any stories or experiences you can share please do and also let me know how you get on with any diet changes.