What we put into our body (and when) directly affects the quality of our training runs. Dietician Nathalie Jones gives the lowdown on how eating well helps us to train better...
In some ways, our bodies are like cars. In goes the fuel and out comes the energy. However, unlike a car, the type of fuel that we take in makes a real difference to how we feel from day to day and how well we train.
During times when we are not training, we may simply feel a bit lethargic, under the weather or may not even notice any difference from a less than ideal diet. However, when we run regularly, slight lethargy is magnified into low motivation to put on the trainers followed by a poor training session and sub-optimum recovery. Done frequently the risk of injury, underperforming and disinterest in running can occur.
The good news, however, is that if you are currently under-fuelled, under-hydrated and lack energy in your diet, a few simple changes can increase your speed, performance and reduce your rate of perceived exertion. When we consider how weight loss can take months of dedication, concentrating on fuelling for running can be a welcoming new approach. There are both long and short term changes that can be made to a runner’s diet that will make a difference.
Making sure that we have enough glycogen stores to run is important so that we can maintain a steady blood sugar level. As we get fitter, we become better at sparing our glycogen and using fat as a fuel but, being under-fuelled in terms of carbohydrate, is likely to result in a poor running session.
A typical situation of being under-fuelled is the ‘after work but before dinner’ run. Often lunch has been a sandwich at 12 and, if the run is not until 6pm, the carbohydrate from that meal has been used up. Adding a bowl of cereal, a few slices of toast or even a cereal bar for convenience, tops up these stores.
The timing of this ‘fuel snack’ depends a lot on individual tolerance but a general guide would be to have some carbohydrate 30 minutes to 2 hours before the run. The type of carbohydrate you choose also depends on when you choose to have it. For example a bowl of porridge or other low glycaemic index carbohydrate could be had 90 minutes beforehand whereas a high glycaemic bowl of rice krispies would be better closer to the run time as the increase in blood sugar happens faster. If the fuel snack is forgotten in the business of the day or an impromptu run occurs, a ripe banana or isotonic sports drink taken close to the run time will tide you over.
If we look at the same example of the early evening run, hydration can also be a problem. Busy work schedules in heated offices can mean that we don’t drink as much as we should. This often leads to ‘panic’ drinks before the run to compensate and a full, uncomfortable bladder on the run. If you know you will be running after work, make sure you get at least 1500ml of fluid in over the day. If you find it hard to remember, a tip can be to have 500ml at breakfast and lunch and another 500ml bottle visible on your desk to sip. Re-filling bottles reminds you of how much you have drunk more than filling cups does.
The benefits of a healthy diet span years and decades. Having a variety of fruit and vegetables daily over years has an impact on long term heart health and cancer risk for example. A balanced diet based on wholegrain carbohydrate, fruit and vegetables, low fat dairy, lean protein and healthy fats is important for runners and non-runners alike.
For a runner, ‘tummy tolerance’ is however also an issue. Whereas a high fibre diet is often advised for the majority of people to help reduce cholesterol and improve bowel function, for runners it can be one of the culprits leading to ‘runners trots’. For regular runners it is about knowing your body. Keeping a food and symptom diary can be helpful for a week or so to identify types and timings of meals before particular runs that are problematic.
There has been some research into the potential benefit of probiotics for athletes in hard training, particularly in enhancing immune function. Although regular moderate exercise reduces the risk of picking up upper respiratory tract infections, athletes in heavy training are more susceptible to infection. Although particular strains of probiotic bacteria are yet to be identified, it may be that taking a probiotic supplement or drink could help improve resistance to infection during periods of heavy training.
Body weight and body fat is often an issue for runners. For some of us, the reason we run is to keep our weight under control or allow us to enjoy treat snacks and meals more often without gaining weight. Others strive for a lower weight than their ‘usual’ weight, to aid performance. It can be helpful to measure weight when doing a time trial or race. By keeping a record of times achieved at different body weights, you can build a picture of your ideal ‘racing weight’. This racing weight does not have to be achieved all year round but may be something that you aim to reach over the months leading up to the race. This is best achieved via a minor daily calorie deficit over months rather than a very restricted diet in the last few weeks which can affect energy and training quality.
In summary, a healthy balanced diet is important for everybody but it is much more obvious when we are training, if our diets are not as good as they should be. Fuel and hydration are two important aspects of our diet that can be fixed relatively easily and can make a real difference to performance and feeling on runs. It is also helpful to have a longer term view of our diets especially concerning training and racing weight.