When your goal is to build muscle, you may think the more protein the better. But should you drink a protein shake during workout? While this question is still under investigation, the general consensus among sports nutrition professionals is no.
Of course, that doesn't mean you can't drink your whey protein shake during your workout. But depending on what's in your shake, it's possible it may make your workout less effective or lead to tummy trouble.
The Need for Protein
Protein is one of the three essential macronutrients your body needs to maintain good health. Carbohydrates and fat are the other two. Often referred to as the building blocks of life, proteins are made up of strings of amino acids that get broken down and reconfigured to create every cell, tissue and organ in your body.
According to the Food and Nutrition Board of the Institute of Medicine, most healthy people need 0.36 gram of protein per pound of body weight in order to meet the body's basic protein needs. For a 200-pound person, that translates into about 72 grams of protein a day.
However, if you're an athlete or bodybuilder, your protein needs are greater. Not only does your body need protein to perform and maintain basic functions, but it also needs protein to repair and rebuild the muscles you work out on a regular basis.
The International Society of Sports Nutrition (ISSN) position stand on protein and exercise published in the June 2017 issue of the Journal of the International Society of Sports Nutrition, says you need 0.63 to 0.9 gram of protein per pound of body weight. For that same 200-pound person that means 126 to 180 grams of protein a day.
- 1 cup of milk = 8 grams of protein
- 3 ounces of lean chicken = 27 grams of protein
- 1 cup of cooked lentils = 18 grams of protein
- One large hard-cooked egg = 6 grams of protein
While it's ideal that your protein come from whole foods, if your daily protein needs are high, you may struggle to get enough from the foods you eat. Protein powders — like whey protein — make a practical option, according to ISSN.
Whey Protein Powder
It may seem as though everyone at the gym drinks whey protein, and there's a good reason: it's an excellent source of muscle-building protein. Whey protein is one of the two proteins found in cow's milk, with the other being casein. Both are high-quality sources of protein, which means they contain all of the essential amino acids your body needs to build muscle.
However, whey has one advantage over casein: It digests rapidly and delivers the right proportions of amino acids quickly for immediate muscle protein synthesis. Whey is also high in the amino acid leucine, which, according to the National Association of Sports Medicine, is the essential amino acid that drives your body's muscle protein synthesis.
- 70 to 100 calories
- 16 to 25 grams of protein
- 1 to 2 grams of carbohydrates
- Less than 1 gram of fat
Your body may not be able to digest casein as quickly as whey, but the high-quality protein provides your blood and muscles with a steady source of essential amino acids, according to NASM, which can prolong muscle protein synthesis.
Timing Your Protein
According to ISSN, when you consume your whey protein powder largely depends on your tolerance. Consuming protein before or after your workout will give you the results you want. Your body can repair and rebuild your muscles for up to 24 hours after your workout as long as it remains in a positive protein balance.
The ISSN further explains that you should aim for 20 to 40 grams of high-quality protein that's rich in the essential amino acids, as well as leucine, to create the positive balance you need for muscle building. Combining a carbohydrate with protein, such as your whey protein powder blended with fresh fruit, Greek yogurt and ice, and drinking it prior to your workout may also help maximize muscle protein synthesis.
Working out without a sufficient supply of energy from a pre-exercise meal may hamper your exercise performance, according to Colorado State University Extension. Ideally, you should consume your pre-workout meal three to four hours before you hit the gym so its fully digested and your body fully energized.
Protein Shake During Workout
Whether you consume whey during your workout really depends on you. If you're an endurance athlete (cyclist or runner) or you engage in intense resistance training, carbohydrates plus protein (such as whey) while working out may minimize damage to your muscles and stimulate the hormones that support muscle building, according to ISSN.
Consuming carbs and protein during exercise may be especially beneficial during endurance training, as it may help prevent your muscles from tiring out.
While there are benefits to drinking a protein shake during workout, there are some potential drawbacks. It's possible that your protein shake may lead to abdominal pain and cramping that can affect the quality of your workout.
Whey protein is easily absorbed in the stomach, so it may not be the source of your tummy troubles. If you're experiencing abdominal discomfort during your workout while you drink your shake, it may be due to a high concentration of sugar, either from the powder or the liquid used to mix it. When a high concentration of sugar hits your stomach, your body draws in water to dilute it, which can lead to stomach cramping and pain.
The shifts in fluid may also lead to dehydration, which can also zap your energy. To minimize digestive issues during your workout, mix your whey protein powder with water and use a brand of protein powder without added sugar.
Post-Workout Protein Powder
You may be focused on protein, but it's not the only nutrient your body needs to rebuild and replenish. While you're working out, your body is using glucose stored in your muscles and liver to keep your energy levels up. To get the results you want, combine your post-workout protein powder with a carbohydrate (fruit, juice or milk) to restore energy levels, so your muscles can concentrate on rebuilding.
Protein powder isn't your only option for your post-workout nutrition. You can also drink a glass of low-fat chocolate milk or eat a turkey sandwich on whole-wheat bread. To get the most benefits out of your post-workout meal, the Academy of Nutrition and Dietetics suggests you consume it within an hour of your rigorous routine.
- MedlinePlus: "Protein in Diet"
- National Academy of Sports Medicine: "The Latest Scoop — Protein Supplements"
- Colorado State University Extension: "Nutrition for the Athlete"
- Food and Nutrition Board of the Institute of Medicine: "Dietary Reference Intakes (DRIs): Recommended Dietary Allowances and Adequate Intakes, Total Water and Macronutrients"
- MyFoodData: "Lentils, Whole Milk, Hard Boiled Eggs, Lean Chicken Breast"
- USDA FoodData Central: "Protein Powder, Whey Based, NSF"
- Academy of Nutrition and Dietetics: "Timing Your Pre- and Post-Workout Nutrition"