Much attention is given to the importance of nutritional choices made directly before exercising. However, choosing what to eat after a workout is equally important. Choosing post-workout foods rich in protein and carbohydrates contributes to expedited muscle growth and repair while allowing the body to replenish its energy reserves for future activity.

Importance of Post-Exercise Protein

Muscle protein balance refers to the fluctuating relationship between muscle protein synthesis (MPS) and muscle protein breakdown (MPB). MPS refers to the rate that the body produces muscle protein for maintaining or building muscle mass, while MPB refers to the rate that the body naturally degrades muscle protein.

When the rates of protein synthesis and protein degradation are roughly equivalent, muscle size remains constant. However, when the rate of synthesis exceeds the rate of degradation, muscles are able to increase in size and strength. MPS rates are largely dependent on protein intake. When you eat protein, the blood plasma concentrations of several amino acids critical for muscle growth increase and stimulate MPS for a few  hours after exercising. The purpose of resistance exercise is to continuously increase MPS rates over time so that the muscles are able to grow faster than they break down, ultimately growing stronger and larger. Eating protein in the hours following exercising enhances this process. 

The protein fibers that make up your muscles also tear and break down when you exercise. Muscle repair and growth results from the body’s efforts to repair this damage, but it needs a steady supply of newly synthesized protein to repair the damaged protein fibers. The protein you eat after exercising not only increases protein synthesis but also decreases protein breakdown, helping to preserve muscle mass that might have otherwise been broken down by the body.

When To Eat Protein After a Workout

male adding protein powder to bottleConflicting opinions on when protein should be eaten after a workout — as well as how much should be eaten — are common within the fitness community. Many say it’s critical to take in a large amount of protein immediately following a workout, but more recent science suggests the rush to eat a protein-filled meal or heavy protein shake in the moments after exercise is unnecessary. People who promote this idea base this advice on the idea of the “anabolic window of opportunity”: The idea that the body best utilizes nutrients for muscle development for a brief period of time directly following exercise.

Though many studies support this idea, the window is likely much longer than the initially proposed time frame of within 45 minutes after a workout. A more recent 2017 study showed that improvements in muscle strength and thickness are similar regardless of whether the post-workout protein is consumed within the traditional 45-minute window or up to three hours later.

How Much Protein to Eat After a Workout

As for how much protein should be eaten when considering what to eat after a workout, more is not necessarily better. Logic suggests that the more protein you consume, the more protein will be available to promote muscular strength and growth, but the body can only use a certain amount of protein during a set period of time.  

For the average adult, this amounts to approximately 20 grams of protein during the recovery period following a workout, though this can vary depending on weight, natural variance in MPS and MPB rates, as well as what foods were eaten during pre-workout preparation. Excess protein is converted to fat or leaves the body as waste. Dietician Jessica Jones recommends using the following simple steps to calculate a rough benchmark for your personal protein needs when deciding what to eat after a workout.

  1. Divide your weight by 2.2. This will give you your weight in kilograms.­­­
  2. Multiply the number obtained in step 1 by 0.4 and 0.5. The resulting numbers represent the range of protein you need, in grams, after a workout.

For example, a person weighing 150 pounds would divide by 2.2 to get 68.2 kilograms. They would then calculate (68.2)(0.4) and (68.2)(0.5) to get a protein range of 27.3 and 34.1 grams.  


Benefits of Post-Workout Carbohydrates

Carbohydrates have earned a negative reputation as harmful macronutrients that have no place in a healthy lifestyle. Diets that promote virtually eliminating carbohydrates, like the keto diet, have gained popularity in recent years and lent further credence to this idea. However, in moderation, carbohydrate-rich foods can fuel the body with essential vitamins and minerals, as well as provide needed fiber and energy. Many health experts and scientific studies encourage eating foods full of carbohydrates to promote recovery and replenish energy after exercising. The more time you spend exercising, the more carbohydrates you will need to eat to meet your body’s demands for energy.

female flexing with back facing camera

Your muscles use up their stores of glycogen, the body’s primary energy unit, to power you through your workout routines. After strenuous exercise, your body needs to replace this lost glycogen. Studies show that the body’s highest rates of glycogen production occur when carbohydrates are eaten directly after exercising because the body relies on carbs to produce it. In the hours following exercise, the body digests carbs and distributes them throughout the bloodstream with greater ease, in turn speeding up glycogen production. When a person delays eating carbohydrates after exercising, muscular glycogen synthesis can decrease by half. Since your muscles continue to repair themselves and build mass for hours after a workout, they need this lost glycogen to support these processes and prepare for additional exercise.

(Muscle glycogen reverts to baseline levels without immediate carbohydrate intake within a couple of days, so eating carbs directly after a workout is less critical if your workouts are not frequent and closely stacked together. Despite the common idea that eating carbs directly after a meal accelerates muscle growth, the evidence does not support this; eating sufficient protein is enough. However, carbohydrates are still necessary for restoring energy and supporting healthy blood sugar levels after a workout.)

Consider the following foods when planning what to eat after a workout:

Scientific literature supports a balanced diet of whole foods packed with carbs and protein for helping your muscles heal and build endurance after a workout. With lean meats like chicken, as well as fruits, nuts, grains, and numerous dairy products on the menu for a healthy post-exercise meal, the combinations for flavorful entrees are infinite. And of course, in your efforts to arrange a satisfying meal after your workout, don’t forget to rehydrate with plenty of water.