top of page

A Crash Course in Nutrition

Food is to your body like gas is to your car: fuel to ensure that you are operating to the best of your ability. Most of you are familiar with the fundamentals of nutrition through your time at school and why it is important. However, as an athlete (especially a competitive swimmer), proper nutrition is crucial to ensure you get the most out of practice and fully recover afterwards. The goal of this post is to explain to you proper nutrition for an athlete as well as why it is so important.

Calories: The Fuel of Your Body

In recent times, calories have had a negative connotation attached to them: Eat too many and you will get fat. In reality, calories in its simplest form is just a measurement for energy. All foods have calories which provide your body with energy once broken down, and your body uses this energy to perform every task imaginable;, whether it be going for a run, opening a jar, or even blinking. The more you are active, the more calories your body requires in order to sustain itself. If your intake of calories is too high, your body will store this excess energy in the form of fat, if your intake is too low, it will utilize fat stores around your body to replenish itself. This is why a lot of diets focus on the amount of calories you consume, and why exercise is so important for weight loss (the more you work, the more calories burned, the more fat is used from your body.) However, there is a point where burning too many calories can be detrimental. This is the point where your body is so deprived of energy, it starts trying to pull energy from the rest of your body in order to refuel itself, most importantly in our case being your muscle fibers and begins to not function optimally. This means that without proper nutrition, you will get weaker and feel worse as a result. So how many calories should you be eating? This is a tricky question to answer, as each individual's caloric needs differ, however, here is a good way to tell. Weigh yourself in the morning at the beginning of the week and again at the end of the week. If your weight stays the same, you are in caloric balance: the amount of calories your body is receiving is equal to the amount of calories being burned. If you’re looking to lose/add weight, you only need to reduce or increase your caloric intake by around 200 calories. Weigh yourself again at the beginning and end of each week, you should only be losing or gaining 1 pound per week at maximum. Anything beyond that is too quick and will have negative effects ( feeling sluggish, headaches, easily fluctuating weight, etc…).

Choosing Your Energy: Macronutrients

Now that we understand why we need calories, we need to understand where we want to get them from. Foods are broken down into three major groups: Carbohydrates, fats, and proteins. Together, they make up what is called macronutrients, the most important aspect of nutrition.

In normal conditions, without a healthy balance of all three of your macronutrients, your body will not operate correctly. This is because your body relies on macronutrients to perform specific tasks that each are more well suited to. Carbohydrates are your body's preferred source of energy: They are a sugar molecule that is fast and easy to metabolize (be broken down and used as energy) and are found in nearly all foods. Not all carbohydrates are created equally, basic carbohydrates such as high fructose corn syrup are quickly broken down and resulting in a “sugar rush” causing you to feel a spike of energy before crashing. On the opposite side of the spectrum, more complex carbohydrates that are higher in fiber like those found in grains are much more slowly metabolized, and give you a more slow and steady release of energy. Fats on the other hand are slightly different. They provide much more calories than carbohydrates per molecule, but they take much longer to be metabolized. Because they are so slow to be metabolized, they give an even slower and long term energy release than carbs, sustaining you for longer. Now this doesn't mean you should eat a stick of butter for breakfast, because just like with carbohydrates, not all fats are created equal. Polyunsaturated and monounsaturated fats found in most oils, fish, nuts, and seeds can promote good heart health in moderation, whereas saturated fats and trans fats found in processed food such as butter, cured meats like pepperoni, and fast food can be detrimental to heart health when not consumed in moderation. Finally, that leaves us with proteins. Unlike carbohydrates and fats, proteins don't really provide our body with energy unless under extreme circumstances (think literal starvation). Rather, proteins are the building blocks for our body. Found in lean meats, beans, and dairy products,they are responsible for repairing and building our muscles and bones. When we workout, our muscle fibers are broken down and the skeletal system is put under stress. Without proper protein consumption your body will not effectively recover from workouts or build new muscle, it will simply be trying to play catch up with the damage from your last workout. If your body were a boat, does it make more sense to have to patch holes once they form, or reinforcing the hull so they don't appear to begin with? Because each macronutrient has a different role within the body, it is important to make sure you have a proper balance of each. As a competitive swimmer, your daily diet should consist of about 60% carbohydrates, 25% fats, and 15% proteins. In order to calculate these numbers, look at the nutrition label of the food you’re eating or google the nutritional facts and add them together. Now, divide each macronutrients total by the total number of macronutrients. Example: I’ve eaten 86 grams of carbohydrates, 42 grams of fat, and 12 grams of protein. Total number of macronutrients =140 grams divided 86/42/12 = 61%/30%/9%. I can then see that my fat consumption is slightly high and my protein consumption is slightly low.

Why It Matters: Your bodies Energy Systems

To some of you, all of this is familiar and pretty basic, however, when we start looking at the exercise specific side of things, we start to see why this is so crucial. When exercising, our body utilizes different energy systems depending on how hard and how long we work. When doing short bursts of high intensity work, we use our muscles stores of energy. This is your glycolytic system, its energy store is small, and needs to be quickly replenished, so the primary fuel source used is carbohydrates (they metabolize quickly). On the other hand, during longer durations of exercise your body will utilize the oxidative energy system, your body will need more and more energy, and fats will then be primarily utilized by the body (they metabolize slowly/provide the most energy). After working out, our body then uses proteins to begin repairing and strengthening your body so that we can be ready for the next workout. All systems are used when swimming, which means all macronutrients are crucial to us. As a rule of thumb, you should try to have 3 balanced meals throughout the day, a small carbohydrate rich snack with some healthy fats before practice (for additional energy), and a protein rich snack within 30 minutes of practice ending.

Time for a pop quiz! What energy source do you think is mainly used for a set of 4x200’s long and strong? What about 10x25’s race pace? Using the graph above can help you visualize the different energy systems and when they are used (Ignore ATP/CP).

Long Story Short

All this leads me to the main takeaway of this post: You need to fuel your body correctly. You are not an inactive person. You are putting your body through rigorous activity that requires the correct fuel to complete your goals. If you arrive at practice having only eaten a granola bar all day, where is your body going to get its energy from when you have a set of 6x 100’s? If you take care of your body, your body will take care of you: More energy, more focus, less soreness, and happier days!

Thanks for reading!

-Coach Dylon

215 views0 comments

Recent Posts

See All


Commenting has been turned off.
bottom of page