Updated: Jun 11, 2019
Due to the nature of my job, I reflect a lot on my race nutrition post event. I have done many a marathon and every single one has been different from a fuelling perspective. Over the 20 years of running, I have trained my gut to be pretty robust. It didn’t start out that way though. I did my first 4 marathons between between the years 2000 - 2004 and I can hand on heart say I took only water and a few swigs of lucozade. Over the years I have worked and worked to tolerate anything from sports drink to pasta whilst on the move. The new challenge I had for London marathon 2019 was fuelling at a much faster pace than I have been used to for a while.
I was aiming to run London to get sub 3. I have been putting it off for years and a gentle push from a few people encouraged me to make this year the one. My aim pace was at 6:40-6:45 min / mile (considerably faster than my ultra pace that I was used to). The faster you move, the harder fuelling becomes (hence why the elite marathon runners will use products such as Maurten which provides a very high carb amount in smallest volume possible) so I needed to practice well in advance and make sure I got it right.
The second challenge was not having my ultra pack with me. These wonderful items provide a huge advantage when it comes to fuelling an ultra. You can use your own drink and carry your own food. Adding that weight to my back however around the streets of London would not have helped me reach my sub 3 target time. Therefore, practicing with the drinks provided on course and tucking gels into my sports bra was the plan.
In sports nutrition, we work on the guidelines of consuming up to 60g of carbohydrate an hour. In reality though, this is quite a lot and equates to approx 2.5 - 3 gels per hour each hour (impossible for many). To make it more achievable, perhaps 2 gels per hour + 250 mls (half a bottle) of lucozade would pretty much hit that carb target per hour head on. Realistically achievable for the first hour but, as fatigue (and taste fatigue) sets in, continuing this for 3-4 hours is hard (and also carrying that many gels in a marathon is logistically tricky). Of course, there is no saying that if you practice far enough out from your marathon, you can train your gut to manage large amounts of carbohydrate an hour, but most runners know their limits.
For me the reality was 2 gels an hour for first 2 hours with lucozade to top them up nearing 50g carb an hour and then if feeling good, a fifth gel in the last 10km.
4 miles (30 mins) - Gel 1
8 miles (60 mins) - Gel 2
13 miles (1:28) mins) - Gel 3
18 miles ( 2 hrs) Gel 4
23 miles (if I could tolerate) - Gel 5
Although many HATE even the mention of gels ( I find people either love them or hate them), for quick easy fuelling they are ideal. There are so many brands out there for you to choose, all different flavours and consistencies. I have used SIS go gels for as long as I remember. I tolerate them really well as the thinner consistency makes them easier to take without water. Other brands such as GU / TORQ are really popular but again very different to SIS due to the much thicker consistency. A lot of runners are edging towards more natural products and the gel industry are becoming wise to this demand. New brands such as Raw Velo have produced an incredible tasting gel that is free from artificial ingredients and 100% organic and vegan (and do taste incredible). My point is, experiment 3-4 months out of your marathon and try as many as you can as you may find one that suits you. Companies like Energy Snacks mean you can choose a selection of different brands and see which ones you like.
One mistake a lot of runners make is stating to fuel too late. As we progress in a race, it can become harder to process carbohydrate as more blood is diverted away from the gut to the working muscles. Starting fuelling early means you are more likely to tolerate it and it will absorb more easily compared to later stages in the race. My plan was always first gel at mile 4 but for some reason by only mile 2 I was feeling like I wanted something. I had eaten really well leading up to the race and also that morning. I tried to second guess it and wonder why I was feeling low but to keep the questioning at bay, I listened to my body and had my first gel early. The key to marathon race fuelling is being flexible and being prepared to deviate from your plan and not let it freak you out. For marathon newbies this can be hard but as your experience grows and you get to understand your body AND the demands of the marathon your confidence will grow to allow you to be more flexible.
I personally don’t drink to plan and tend to drink to thirst and how I feel. I find it easier to drink to plan when I carry my own water in ultras. I know how much I have and how much I should aim to drink per hour (it is measurable when you are carrying it yourself). Some runners respond better to this plan in a marathon and some respond better to drinking to demand. Like London, most marathons have so many water stations there is no fear of lack of opportunity to drink. I can’t put a number on how much fluid I consumed but I probably took a few mouthfuls per bottle at maybe every other station. It is something worth practicing in training though. Grabbing a water bottle and drinking on the go whilst keeping pace can be hard. Practice will make it less alien and something I know many, including myself, need to work on. In training, work out a circle route and leave a bottle at your front door, or set up a table outside your drive. Practice when you are doing those marathon paced efforts in training so when you get to race day you are familiar with the process.
So, the question remains, on reflection, was did I execute my perfect race nutrition plan? It wasn't too far off! I managed 5 gels ( 2 per hour for first 2 hours and 1 in last hour) which I was really happy with. I may have needed more water / lucozade BUT I felt well fuelled and didn't feel like I lacked energy (I picked up pace well for last 5km which is a good indication of being well fuelled).
My main advice is for fuelling a marathon:
1. Have a plan
2. Practice the plan
3. Don't be scared to deviate from the plan on the day if things change.