Hi Fearless Fam,
Let’s talk about eating after a workout. On the internet, through your coaches, and in many various forms we hear “make sure to eat after your workout.” But what exactly does that mean? This questions in many cases only leads to more questions. Do I need to eat immediately after my workout? What about protein shakes? Do I need to have food with me to eat before I even leave the gym? Do I just need to eat at some point? How long do I have before the benefits wear off?
Well first, let’s look at why you should eat after the workout. For this scenario, I am speaking directly to people who work out in High Intensity Intervals, such as we do at CrossFit and Fearless (and most, if not all, CrossFit gyms do). In CrossFit, we tend to work out a lot within the “Glycolytic” window of energy. What this means is that the main energy source we use during a lot of our work outs tends to come from our glycogen system. The energy in the Glycolytic system is derived from Glycogen, or sugar, stored in our muscles that then gets circulated through the blood. There are 3 major energy systems used by the body in exercise, as demonstrated in the chart below.
As you can see above, a lot of our short-term energy comes from the Glycolytic system. Think about the way a standard CrossFit class is structured and think about what energy systems are used based on the chart above. In a workout where you are working for 30 seconds to 2 minutes at a time, you are primed to be working in your Glycolytic Energy System. Examples of workouts that are in this window: 200-400m run, 250-500m row, a set of 6-10 squats, 50 Double unders, etc.
When we burn the energy from that energy source during the workout, we need to replace it. The best way to get this energy replenished is to replace the glycogen in the muscles. The way you can replace glycogen in the muscles is by eating carbs. Carbs turn to sugar during the digestion process and get absorbed into the blood stream to help replenish the glycogen lost during the workout process.
That’s why we eat carbs after a workout. By now you might be thinking “But what about protein, Derec?” Well let’s talk about that. Protein is essential to eat post-workout as well. When you are exercising, you are actively causing “trauma” on your muscles by putting them through physically stressful situations. In these moments, your muscle literally breaks down, so we need to be able to give it the nourishment to rebuild itself even stronger than before.
Muscle building happens through a process known as Protein Synthesis. Protein Synthesis is a very complicated cellular process that I can’t fully explain here, but for the means of this discussion let’s just interpret protein synthesis as muscle rebuilding. One of the driving factors in the rate of protein synthesis post-workout is the availability of amino-acids in the body, which come from protein sources. Once your muscles are broken down, they are depleted of their amino-acid stores so we need to get those amino acids through a source outside of our body, aka protein.
Nutrition is THE MOST IMPORTANT part of any training regimen. You spend the time putting in a large amount of effort in the gym already, so you should be putting that effort in nutritionally to maximize the benefit you can get from fitness.