Following and understanding the basic principles of a healthy balanced diet and living an active life is important to staying healthy.
Carbohydrates are one of the three macronutrients of the diet and their primary role is to provide the body with energy. They are often split into two groups and referred to as ‘simple’ and ‘complex’ carbohydrates. Simple carbohydrates include sugars such as glucose, fructose, lactose which are present in foods such as fruits, vegetables and milk, but also as table sugar and in confectionery. Complex carbohydrates are made up of single carbohydrate molecules joined together in longer chains and include starchy foods such as pasta, bread, rice and potatoes.
Carbohydrates supply the body with energy, with 1g providing 4kcal of energy. Glucose, one of the simplest carbohydrates, is the preferred energy source of the body and brain, which need a constant supply to function. When we eat a high-carbohydrate meal, some of the glucose goes into the blood for immediate use. The excess is transported to the liver and muscles to be stored as glycogen. This storage form of glucose is what the body relies on during longer duration exercise such as marathon running.
Carbohydrates will become your best friend during your marathon training. As you start training for longer distances and durations your body begins to rely on your stored muscle glycogen. In the week before the race, increase the proportion of carbohydrates in your diet, but try not to increase your total calorie intake too much. If you are tapering your training and resting more, you could find yourself putting on weight. This will ensure that your stored glycogen levels are as high as possible giving yourself the best possible engine ready for the start of the race. Stick to foods you are familiar with.
The 24hours before is a key time in your marathon preparation. Have a good, high carbohydrate meal but one that you are used to the evening before. Pasta, rice or potatoes are good options. After a good sleep, you need to consume another carbohydrate loaded breakfast in the morning. It is recommended that this meal is made up to 1-4g of carbohydrate per kg bodyweight, around 2-4 hours prior to the start. Experiment with different options during your training and find a meal that works for you. Keep fat and fibre to a minimum as these can cause stomach upset.
Like cars, our bodies cannot run on empty. As we exercise, our fuel stores will gradually decrease and we may become fatigued if we don’t top them up. This may mean slowing your pace down, walking or even having to stop if our energy levels drop too low. Therefore, it is essential to continue to take on fuel in the form of carbohydrates during the marathon. 30-60g of carbohydrate per hour is recommended. Use your training runs to experiment and find a strategy that works best for you. As with hydration, small amounts little and often is generally the best way to avoid stomach discomfort.
26.2 miles is a long distance to run and will take most people between 3 hours and 7 hours to complete. The recovery process starts as soon as you cross the finish line. Even if you do consume fuel during the race, your glycogen stores are almost certainly going to be very low. It is important to replenish your body with a high carbohydrate and protein meal as soon as is convenient to get your body back to its pre-event condition. Be prepared that it will take several days for you to be back feeling at your best.
Protein is another macronutrient. The building blocks of protein are called amino acids, which are classified as ‘essential’ or ‘non-essential’. In total, there are 20 amino acids, 9 of which are essential and therefore must be consumed through the diet. The remaining 11 are non-essential and can be made by the body. The amino acids are joined together in different sequences to make a protein. Different foods contain different amounts and combinations of amino acids, so getting a good variety within the diet is important.
Protein is present in a variety of foods that we regularly consume. Animal proteins, such as meat and fish are considered high quality as they contain all the essential amino acids we need. Eggs and dairy are also good sources. However these sources can also be high in fat. Those who are vegans or vegetarians can get their protein intake through plant based sources such as beans, pulses and cereals. Although these are generally lower in fat, they do not provide all of the essential amino acids, therefore combining different sources is important. Try to eat a large range to keep the diet balanced and varied.
Protein is the second most abundant material in the body – after water – making up about 20%. It’s a fundamental structural component of cells and necessary for virtually every activity in the body. Functions include carrying oxygen around the body in blood via haemoglobin, forming antibodies to protect against pathogens and forming enzymes to catalyse reactions such as the breakdown of food. However, approximately 50% of the body’s protein is found in skeletal muscle. These actin and myosin proteins contract and relax, creating movement.
When we exercise, the additional force and loading through the muscles create microscopic tears within the fibres which can result in muscle soreness. This soreness often comes on gradually, peaking around 48hours post exercise, and is termed ‘delayed onset of muscle soreness’ or DOMS. There is no proven way to prevent DOMS, however there are strategies suggested to reduce their severity, one being consuming good quality protein in your diet, particularly after exercise. The body rebuilds itself using the protein which provides amino acids to repair the muscles and over time they adapt to the exercise, growing and increasing in strength and size.
If you are new to running, or have only run short distances, marathon training will likely come as a shock to your muscles, in particular those of the lower limb. Recovering after each training run is important to allow you to keep to your training schedule. During your training increase your daily protein intake to between 1.2-2g/kg bodyweight per day, and aim to consume a protein meal or snack as soon after your run as possible. This will enable the muscle tissue to start rebuilding and repairing any damage and adapt to the demands being placed upon it.
Contrary to popular belief, not all fats are bad for you. In fact, some are essential and form a very important part of a balanced diet. Fat is one of three macronutrients in the diet and they are made up of different types of fatty acids. These fatty acids are usually classified as saturated, monounsaturated or polyunsaturated, and this depends on their chemical structure. The structural differences influence their health effects, and we should aim to consume mono- and poly-unsaturated fats, whilst limiting saturated fats as these can have adverse effects on health.
Fat is the most energy dense macronutrient in the diet, providing approximately 9kcal per 1gram of fat. This makes it the likely contributor to any weight gain. Certain fats are really important in the diet as some vitamins are fat-soluble, meaning fat in the diet helps to absorb them. These include Vitamins A, D, E and K which have high importance in the diet.
Most of the fat in your diet should come from food sources of polyunsaturated and monounsaturated fats. Foods that contain these fats include fish, nuts and vegetable oils. In fact, it’s recommended that we consume 2 portions of oily fish per week, such as mackerel or salmon. We should be limiting the amount of saturated fats in the diet to less than 10% of our overall energy intake. These fats – for example, cheddar cheese – are associated with an increased risk of heart disease and high cholesterol. Moderate your intake or, where possible, look out for the low-fat options.
Although fibre is not technically a macronutrient, it remains an important part of a balanced diet. It cannot be completely broken down by digestive enzymes and contributes to a healthy gut. It is found in many cereals, as well as bread, beans, fruit and vegetables. The recommended daily amount of fibre is 30g per day, but the majority of the UK does not reach this target. Recent data show that men consume on average 20.7g per day and women only 17.4g.
Fibre is important to keep the digestive system healthy. It delays the absorption of glucose and cholesterol resulting in lower blood cholesterol and reduced spikes in blood glucose. It can also help increase the number of good bacteria in the gut. In terms of long term health, higher intakes of fibre are associated with a reduced risk of cardiovascular disease, type 2 diabetes and colorectal cancer.
Vitamins and minerals together are called micronutrients as they are required by the body in small amounts, and are essential for many processes within the body. Most vitamins must be obtained by the diet as the body cannot make them itself. There are two groups of Vitamins, fat-soluble and water-soluble. Eating a well balanced and varied diet, with lots of fruit and vegetables will likely mean you reach the recommended nutrient intake. Supplementing may be required for certain population groups to achieve the normal requirements.
Similar to Vitamins, Minerals are essential micronutrients needed by the body in small amounts. Dietary reference values are established for each individual mineral, and these values change depending on age, gender and stage of life e.g. baby, child, adolescent, adult. Eating a varied diet will help ensure you have an adequate supply of minerals. Some groups are more at risk of being deficient in certain minerals, for example iron deficiency is more common in adolescent women. Supplementing may be required for certain population groups to achieve the normal requirements.
Since its launch in 1990, Lucozade Sport has become the UK’s number one-selling sports drink and has partnered with the London Marathon since 2000. The carbohydrate-electrolyte solution has been extensively researched in laboratory environments and participants have consistently seen performance benefits when undertaking endurance-type exercise. Lucozade Sport provides carbohydrates and electrolytes that help to enhance hydration and maintain endurance performance. Sipping little and often throughout your training runs and the race will keep your muscle glycogen stores from dropping too low while offering hydration benefits. The ribbed bottle is easy to grip, and the sports cap means you can drink it efficiently and easily while on the go.
Lucozade Sport gels provide two sources of carbohydrate for even more fuel. The body can only absorb a maximum of 60g glucose per hour. Glucose transporters from the gut into the bloodstream become saturated at this level and further glucose intake will sit in the gut and could cause discomfort. Fructose, another carbohydrate, can be absorbed alongside glucose due to its different pathway into the blood, allowing an additional 30g of carbohydrate to be absorbed per hour. This makes dual fuel gels a great marathon partner as they can provide a more concentrated source of energy.
When you consume any sort of gel it is really important to have some water alongside it. Not only will the water make it more palatable in the mouth, it will also provide you with hydration that the gel doesn’t. This is a really important point to remember when you use them. If you haven’t used gels before it is recommended to start practising with them during the early stages of your training to allow the body sufficient time to adjust to them. Their compact and small size makes them a really convenient choice for fuel when you are out running for long periods. Do not try these for the first time during the Marathon!