A guest post by Alex Cook The Sports Dietitian – Sports nutrition & performance
The London marathon is the ultimate goal for many runners and at 26 miles 385 yards there is no doubt there is something charismatic about the adventure of pre-training, the event itself and the ensuing recovery period. No matter what your level or experience, preparation is definitely the key ingredient.
Careful thought about training and nutrition is imperative and there is such a fine line between achieving goals and hitting the dreaded wall. The metabolic demand on the body over this distance is immense. Correct fuelling is essential and if done wrongly the last few miles may be painful!
The main nutrients used to power runners over the distance are carbohydrate and fat, with the relative contribution of each depending upon factors such as training status and pace. Carbohydrate is not only required to fuel running, but also to restore muscle and liver glycogen levels during recovery.
The week before
Increasing carbohydrate intake this week does not mean overeating!!
Although all the hard work is done, keep your focus. Adequate fuelling the week before the race is vital, as poorly fuelled muscles cause needless fatigue. The aim of pre-race nutrition is to optimise fuel stores (muscle glycogen) and hydration status. Reducing training load (tapering) while consuming a high carbohydrate intake (5-8g/kg.bw per day) for 2-3 days before the race will ensure muscle glycogen levels will be replenished ready for racing. This increase in carb intake though should not be a result of eating more but by reducing fat intake and focusing on carbohydrate rich foods in meals and snacks. Using sports drinks are a good way of increasing carb intake without making you feel too full. Be prepared though, putting on some weight in this phase is common. Every gram of glycogen stored, holds 3 grams of water, however, don’t be too concerned, this stored fuel will help power you through your race.
The day before, have your biggest meal at lunch and a lighter meal in the evening so you are not overly full going to bed. Trying new foods on the day’s leading up to a race is not advisable and could lead to disastrous results on the day. On the morning of a marathon race, a light and carbohydrate rich breakfast such as cereal and toast or pancakes with jam 3-4 hours before the race will top-up energy stores and ensure enough time is left for digestion.
An hour before the race topping up with a high carbohydrate snack to make sure energy stores are maximised.
During the race
Staying hydrated is vital. In average temperatures, aim to drink 150ml every 15 minutes (average 1 cup every 2 miles). The drink stations can be crowded, especially in the early stages, so be prepared!
During the marathon, intake of carbohydrate is advisable. As a general rule, 30-60g/hr of carbs should meet race demands (one energy gel = 27g carbohydrate and a 500ml sports drink = 32g carbohydrate).
Studies have shown that ingestion of even small amounts of carbohydrate can improve performance, so if you can’t manage much, even a small amount will help. Solids and liquid carbohydrate will provide the same in terms of fuel, with sports drinks and some gels having the added advantage of replacing lost electrolytes lost through sweating. Energy gels or bars can be used, but may be less well tolerated by the gut. Intake should start soon after starting and continue at 15 minute intervals. With sports drinks, it is impossible to measure how much you are having so 6-8 mouthfuls every 15 minutes is a rough guide. You can test all these approaches during training and see what works best for you.
Remember the Golden Rule..don’t try anything new on race day before or during. You may regret it and spend most of your marathon in the portaloo.
After the race
After you’ve completed the distance your energy stores will be empty. It is common to lose your appetite for the first few hours, but try and eat something within 30 minutes of finishing. Muscle glycogen is slow to replenish, so follow this up as soon as you can with a carbohydrate and protein-rich meal to help start the recovery process. Continuing to hydrate is important, so drink water regularly for a few hours post-race. The week following your gargantuan efforts, focus on a balanced diet rich in carbohydrate and protein to continue the recovery process and if you are craving something – listen to your body!
The most important thing to remember is, we are all individuals and although there is generic advice, one plan does not suit all. Experiment during training to see what suits you and once you have a race day plan, you can stand at the start line with confidence. Relax and enjoy, the marathon is a race you will never forget ever!
The week before:
- Reduce training load and follow a diet high in carbohydrate (5-7g/kg.bw) 2-3 days before you race
- If you suffer from GI problems when you run, you may want to reduce your fibre intake a few days before (limiting fruit and vegetables and opting for white bread, pasta etc.)
- On the day, have a light breakfast that is high in carbohydrate leaving plenty of time for digestion
- Start hydrating as soon as you wake up (at least 500ml before you run) and during the race aim for 150ml every 15 min.
- Take on carbs during the race (30-60g/hr) Sports drinks, bars and gels provide the same in terms of fuel but sports drinks and some gels replace electrolytes lost in sweat.
- Post-race the focus on nutrition doesn’t stop. Eat a snack within 30 min of finishing and make sure this is followed up by a carbohydrate and protein rich meal as soon as you can tolerate it.
- Keep hydrating (you know you are hydrated when your urine is clear).