What to eat? What not to eat? Those are the questions. Well, some of the many diet-related questions that niggle us runners. However, one of the more pertinent considerations is that of protein, its role and how to get enough of it. Irish Runner consulted with experts at the Irish Society for Clinical Nutrition and Metabolism for some advice on this topic. Pay attention, here comes the science bit…
The objective for the competitive distance runner is simple, to get from A to B as fast as possible. However, as we saw in the ambitious Breaking2 project, Eliud Kipoge, supported by a team of world-leading coaches and sports scientists, was not able to break the two-hour mark in the marathon distance, despite achieving maximum performance with immense work across all aspects of preparation. More is thus needed.
The goal for endurance cyclists and long-distance runners is to be as light as possible while maintaining the highest average power output over the distance. Achieving an optimal power-to-mass ratio is one of the keys to victory or a new personal best. However, it is not simply a case of losing as much weight as possible, rather it’s about the quality of weight loss.
Traditionally, distance runners planned training sessions based on lactate thresholds and managed training loads, making sure to taper and peak in time for competition. Between and within those training sessions, carbohydrate is strategically consumed. More athletes now apply established scientific principals and undertake lower-intensity sessions in a carbohydrate-depleted state to increase their ability to use fat as a fuel. However, elite athletes are realising that protein matters and, when combined with strength training, the effects on both health and performance are significant.
Protein and muscle
An athlete will turnover 1.2 per cent of their skeletal muscle per day. This is a balancing act between synthesis and breakdown or, put simply, addition and subtraction. What determines addition is the protein we eat and the physical activity we undertake. When we rest for a week in bed, we lose significant muscle mass and strength and when we do this in the fasting state the results are frightening. Not surprisingly, when a distance running does not consume enough protein, muscle is lost. Muscle is what carries you to the finish line and is vital to success because the power-to-mass ratio is determined by how much force your muscles can generate.
How much protein do you need?
The guideline for the average person is 0.8g of protein per kilogramme of body weight.
However, for an athlete undergoing strenuous training up to six days per week, at least 1.2g of protein per kilogramme body weight is needed to ensure maintenance of muscle. To maximise uptake into muscle and prevent losses, the intake should be split as evenly as possible over at least three meals per day. In practice, protein distribution tends to be loaded in the evening meal and be too light in the morning – checking your intake at breakfast and lunch and adjusting accordingly is worth the effort.
Interestingly, for the average runner, especially novices, more than 10 per cent weight loss may sound desirable, but in this case, aiming for an intake of 1.5g of protein per kilogramme of body weight will help maintain your muscle while the rest of your body is catabolic.
When do you need protein?
There has been an obsession with consuming protein immediately after a training session to take advantage of a supposed ‘anabolic window’. However, while this is likely to be helpful it is even more beneficial to spread protein intake throughout the day. For most runners of average body weight, this will typically mean achieving a protein intake of between 25g and 30g in the morning, mid-day and evening. The evidence is even building for consuming some protein (typically around 20g) before sleeping. When we sleep, growth hormone is released, stimulating muscle protein synthesis. Consuming protein before bedtime provides the amino acid building blocks that can utilise the anabolic benefit of growth hormone secretion, improving the muscle adaptive response to exercise training.
What type of protein do you need?
You need protein that is high in essential amino acids as humans cannot produce these naturally. Since protein from animals is almost identical in composition to human protein, it supplies all the essential amino acids needed to rebuild or repair muscle, giving it a high biological value. Leucine is a key essential amino, which slow muscle degradation and improves muscle function. Therefore, eating foods that are high in leucine is vital for athletic performance. Leucine is found in all animal protein, whereas, plant-based protein sources vary, putting vegetarians and vegans at a higher risk of muscle depletion if special dietary advice is not followed. Soy products, such as fresh soy beans (Edamame), soy dairy products, and roasted soy beans are particularly good plant-based sources of high-quality protein and leucine. As protein is highly satiating, it can be difficult to eat enough throughout the day. Supplementing protein is a safe and effective option provided you ensure the supplement you use has been sufficiently tested to exclude any banned performance-enhancing substances.
Protein content of foods – a quick guide
With so many apps and tracking devices to choose from, it is easier than ever to check if dietary intake is meeting your nutrition goals. However, as a general ‘rule of thumb’, the amount of protein in one egg is around 7g, which is the same amount you would obtain from 30g (raw weight) of lean meat such as chicken or beef, fish, white fish or even nuts such as almonds. When it comes to dairy, this amount of protein would be provided in a small glass of milk (200ml) whereas beans and peas would provide around 8g, or so, per 200ml pot/can.
Useful sources of protein and leucine to consider
Eggs (13g protein, 1.1g leucine per 100g)
With an ideal amino acid profile, eggs are an excellent source of protein and leucine and come out better than most other foods when compared on a ‘per calorie’ basis.
Oats (11g protein, 1.2g leucine)
Although oatmeal is not a particularly useful source of high-quality protein, they make an ideal basis for an athlete’s breakfast with a surprisingly useful amount of leucine. Combine with milk, fruit and some nuts for an ideal start to the day, adding an egg or protein supplement if you are still short on your dietary targets.
High-protein yoghurt (10g protein, 1.0 leucine per 100g)
In recent years, dairy manufacturers have responded to the demand for higher protein, low/no-sugar yoghurts of athletes but don’t be put off by images targeting the rugby players. Runners can benefit too.
Almonds (21g protein, 1.6 leucine per 100g).
Always consult with a qualified nutritionist or dietitian before you make changes to your diet.
Increasing your protein intake can help improve the quality of weight loss and support your training as you prepare for your big run.
Remember to consume protein throughout the day with a focus on high-quality animal sources during your main meals with protein prior to sleeping potentially giving you that extra edge.