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Do You Need Protein Right After Your Workout?
If you’re wondering whether that post-sweat protein shake is as important as people say, you’re not alone. Here’s the bottom line.
You push out that final rep and let the weight crash to the floor as you finish up your final set. Workout complete! Now it’s off to shower—but not before you reach for the protein shake you stashed in your locker pre-workout. Why? You’re looking to increase muscle mass and heard that the key is consuming protein within an hour of your workout. But how much truth is there to this nutritional rumor? Why is protein so important? And who decided 60 minutes is the magic cutoff for its effectiveness? Here’s what the pros have to say about fact versus fiction when it comes to maximizing your muscle gains.
What Happens to Muscles When You Work Out
Lifting weights feels tough most of the time—and it should. That’s because when you strength-train, you’re essentially causing micro-tears within the muscle fibers. “These micro-tears stimulate the body’s repair response via nutrient delivery to the muscle cells, to repair the damage and stimulate more myofibrils to grow,” explains Pittsburgh-based Leslie Bonci, R.D., a nutrition consultant for both a professional football team and the Pittsburgh Ballet Theatre. “The increased number of myofibrils causes muscle fibers to enlarge, increasing their volume and size.” In other words, by working out and breaking down your muscle fibers, you’re giving them the opportunity to then grow back stronger. “Post-workout is the time for muscle fibers to recover and increase in strength,” explains Bonci. “Protein is essential in this process.”
Protein’s Role in Building Muscle
Here’s how protein fits into the picture: When you work out, the protein in your muscles breaks down (see: micro-tears). To repair and rebuild this muscle damage, your body goes through a natural process known as protein synthesis, where it produces more of the stuff in order to help muscles heal. “In a nutshell, protein provides building blocks called amino acids that are needed to heal muscle fibers from the wear and tear that they incur during training,” explains Los Angles-based sports dietician Cynthia Sass, R.D., a former nutrition consultant for the a professional baseball team.
The goal, if you’re seeking to build muscle, is to have the amount of protein synthesis exceed the amount of protein breakdown. “If there is more muscle protein breakdown than synthesis, it results in catabolism or muscle loss,” explains Bonci. And since your body can only produce so much protein on it own, supplementing with protein-rich food after your workout can help ensure you’re getting enough to facilitate muscle growth.
Timing Your Protein Intake
In order to prevent the loss of muscle mass, you need to have protein readily available to help rebuild your tissue damage. Research shows that it’s in the first few hours after you finish resistance training that your body is most receptive to using protein for muscle repair and growth.
There is some debate about this timing though. Some research shows that consuming protein immediately after training, along with eating an adequate amount of protein evenly distributed between three to six meals per day, is ideal for maintaining, repairing and building muscle tissue. However, other research suggests that the window of opportunity for utilizing protein for repairing muscle may be up to 24 hours.
The prevailing wisdom seems to be that sooner is better. “Many sports dietitians, including myself, generally recommend aiming for about 20 grams of protein within an hour of the end of the workout, along with 40 grams of carbohydrate to stimulate muscle repair,” explains Sass. “Exact protein needs may also depend on other factors, including the type and frequency of training, age, carbohydrate and calorie consumption, and if your goal is weight loss versus weight gain.” In other words, if you’re an athlete doing more than one intense workout a day, you may need more protein at different frequencies than someone who is walking for exercise.
Best Sources of Protein
As for where to get the goods, milk, Greek yogurt, cheese, eggs, tuna, chicken, turkey, lean red meat and shellfish are all solid bets. Plant-based protein sources include tofu, soy based burgers, lentils, quinoa, chickpeas, almonds and hempseed.
Both Bonci and Sass agree that the consumption of leucine-rich food is also important: This specific amino acid plays a key role in the synthesis process. Good sources include eggs, chicken, beef, pork, fish, canned beans and tofu. “Aim for about two to three grams per meal,” says Bonci.
Whey protein isolate also contains a high amount of leucine, which, along with convenience and ease, is one reason that protein powder shakes are such a popular post-workout go-to.
Too Much of a Good Thing
Just because you’re weight training though, doesn’t mean you need to have a shake immediately following your lift. “It is not always necessary to have a protein supplement post-lifting if you are going to be eating a meal within two to three hours after resistance training,” explains Bonci. “If you lift, and then have a protein shake, and then a grilled chicken salad within an hour, that is excessive protein intake.” Your body can only use a certain amount of protein at once; anything beyond that will pass through your system.
Plus, overconsumption of protein may mean under consumption of carbs and fat—and it’s the balance of nutrients that your body needs for energy to perform at its best. “Put the protein on the plate, but be complete with what you eat by adding carbs and fats, too,” says Bonci.
With the right fuel in the tank, you’ll be ready to hit the weights again.