What you eat in your daily life has an impact in how well your body will be able to perform in training and on race day. Many athletes we coach are either trying to lose a few pounds, looking to optimize their performance, or simply seeking a healthy, well-balanced diet. This article outlines some key nutrition information and builds from very basic to slightly more intermediate levels. At the end, I also address some common misconceptions that I see causing confusion.
Level 1: Quantity and Calories
At the most basic level, we can think of food in terms of quantity which is most often measured in calories. Calories are a unit of energy. Food provides us the energy our bodies need to survive, move around all day, complete workouts, and build muscle after workouts. We need to keep our total caloric expenditure (everyday life + workouts) in balance with our total caloric consumption (how much we eat). Or, if you’re trying to lose weight, you need to eat fewer calories than your total caloric expenditure. If you find yourself eating more calories than you’re expending, you’re likely going to gain weight.
Level 2: Macronutrients
Protein (target 10-25% of your diet): Protein is used to build muscle. The best times to eat protein are during meals, after a workout, and just before bed. You do not need to eat protein during most workouts since it is not used as energy to fuel workouts. Small amounts of protein can be beneficial during longer exercise (over about 3 hours).
Carbohydrate (target 40-65%): Carbohydrates are used for immediate energy, with higher intensity exercise, over shorter duration. Your body is still burning carbohydrate for energy during longer, moderate and low intensity exercise, but it becomes the secondary fuel source. The best times to eat carbohydrates are shortly before, during, and after exercise and during meals. You should avoid eating carbohydrates in the couple hours before bed since you’re about to be sedentary. When your body consumes carbohydrate, it immediately converts it to glycogen and stores it in your muscles. Our bodies have a limit to how much glycogen they can store (typically around 1200-2000 calories), and any carbohydrate you consume beyond that limit will get converted to and stored as fat.
Fat (target 20-30%): Fat is used as energy in longer, moderate to low intensity exercise – it’s the main fuel source we use in endurance sports. The best times to eat fats are during meals. You should avoid eating fats shortly before and during exercise as it can cause GI issues. It also takes your body 10-12 hours to metabolize fat, so keep in mind that the fat you eat now won’t be ready to fuel exercise for 10-12 hours.
Level 3: Simple and complex carbohydrates and their impact on blood sugar/glycemic load
Blood sugar (glycemic load) is just that, the amount of sugar in our blood. Our blood sugar levels will naturally fluctuate throughout the day as we eat, digest, and exercise. Our goal needs to be to try and keep those fluctuations gradual and small instead of rapidly rising or falling to extreme high or extreme low levels. Carbohydrates are sugars, so we need to focus on what types of carbohydrates we’re eating in order to manage our glycemic load.
Simple carbs: Simple carbs are high glycemic foods which means they are digested quickly and cause a very fast and very high rise in blood sugar levels. This is a bad thing, so we want to avoid simple carbs in our diets. Simple carbs include foods like desserts, table sugar, soda, candy, white bread, and others.
Complex carbs: Complex carbs are low glycemic foods which means they are digested gradually, so they cause a slower rise in blood sugar and also a lower overall rise in blood sugar. These are good things, so we should try to pick complex carbs for our carbohydrate needs. Complex carbs include whole grains, whole wheat bread, potatoes, sweet potatoes, brown rice, beans, chick peas, and more. Although at a molecular level, some foods like fruits and milk are simple carbs, you can think of them as being in the same category as complex carbs since they act more like complex carbs because they have plenty of vitamins, minerals, protein, and fiber which results in the same gradual blood sugar increase that you get from true complex carbs.
In practice, this can actually get pretty confusing because it’s not entirely black and white as to which category a given food falls into. It’s probably more accurate to think of simple vs complex carbs as a spectrum rather than two distinct buckets. Some clues to look for are the amount of fiber and how refined/processed the food is – you want more fiber and less refinement/processing (ex. choose whole grain breads with visible grains, seeds, nuts, etc. instead of white bread which is highly processed). Also, if you stick to natural sources of carbs like fruits, vegetables, and dairy, you’ll be good.
Read more on simple and complex carbs here.
Level 4 and beyond
There is more beyond this information! Keep in mind that additional information builds on this foundation – it does not replace this foundational information. It’s just like how we all learned math growing up. First you learn basic addition and subtraction, then you learn your multiplication tables and long division, eventually maybe you continued to more advanced topics like algebra, trigonometry, calculus, and beyond. Each new advanced topic builds on the knowledge from the prior grades. If you can get the information outlined here correct though, you’re going to be doing pretty well. Then if you want to continue to learn more, that’s great too!
Common Misconceptions: Fad Diets
We need to be careful about chasing fad diets. Fad diets typically follow the outline of, “Only eat this, never eat that.” Typically, what happens with fad diets is that when someone starts the diet they see initial success and weight loss. This is primarily because of the ‘never eat that’ part of the diet’s rules. By cutting out a significant part of the dieter’s food intake, the diet will be successful in getting that individual to initially lose weight. In the long term though, many people end up struggling with fad diets because the diet is either too restrictive or because the person finds replacement foods that technically follow the guidelines of the diet but still end up giving the person too many calories overall.
Common Misconceptions: Calories
“Counting calories alone is not enough” vs “Calories don’t matter” / “Calories aren’t a thing”
It is absolutely correct that counting calories alone is not enough if you are trying to watch your weight. Countless individuals struggle to lose weight even after significantly reducing their caloric intake because they still have a poor mix of macronutrients or are eating lots of simple carbs.
However, “Counting calories alone is not enough” is a very different statement than, “Calories don’t matter.” The first is correct while the second (calories don’t matter) is most definitely not correct. This is an important distinction to keep in mind for two reasons. First, an endurance athlete (and by endurance athlete, I don’t just mean professionals – I mean anyone completing and training for runs, bike rides, triathlons, etc. at any pace) typically follows a training plan that consists of both an off season where your volume is relatively lower (say 20-30 miles per week for a runner) and peak training season where your volume gets significantly higher (40, 50, or even more miles per week). With this type of training, your body needs fewer calories during the off season and more calories during peak training. If you aren’t able to adjust throughout the year, you’re going to find yourself either gaining weight in the offseason because you’re eating too much or struggling through workouts during peak season because you’re eating too little and your body is out of energy. Second, even if you are eating an appropriate diet of the right foods (complex carbs, healthy fats from plants, etc.) you can still gain weight if you’re eating too much of it and your caloric intake exceeds your caloric expenditure.
Common Misconceptions: Carbohydrates are the enemy
The trend right now is that carbs are the enemy. Carbohydrates are not the enemy and not all carbohydrates are bad for you. You need to include complex carbohydrates in your diet – especially if you are an endurance athlete (again, I mean all levels of endurance athletes, not just the pros). You do need to keep in mind your overall balance of macronutrients to make sure you’re not getting more carbohydrates than you need, but carbohydrates are a part of that balance.
Simple carbohydrates are the enemy. This is true and this is what experts actually mean – it just gets misstated by many other individuals. Unfortunately, simple carbohydrates are abundant in our culture. They’re hard to avoid if you eat out much, so you’re better off preparing your own meals where you can ensure you’re not dumping extra sugar in everything like many restaurants do. If you do eat out, try to be conscious of where you go and what you order.
Low carb and no carb diets are also catching on right now because the average American leads a pretty sedentary lifestyle – they drive everywhere instead of walking, they don’t get much or any exercise, and they sit in an office job all day. If you’re an endurance athlete (again, I mean all levels of endurance athlete), you’re not the average American leading that sedentary lifestyle. The average American does not run marathons, complete Ironmans, or participate in century rides. Endurance athletes of all ability levels need carbs – you don’t need to go overboard with them, but you do need them.
Sources: USA Triathlon, RRCA, Jesse Kropelnicki