The What and When of Post Workout Shakes
In the early days of physique competition, the champions would finish their workout with a calorie-dense protein shake loaded with ice cream, bananas, nuts, and even raw eggs. This evolved into post-workout carb drinks, whey protein shakes, and pre-mixed formulas with added vitamins, minerals, and even probiotics. So what should you drink post-workout, and further, when should you drink it – inquiring minds, and bodies, want to know!
The place to start this discussion is by determining your goals. One reason the first competitive bodybuilders consumed a protein shake was that it was a relatively inexpensive way to add calories to help them bulk up. The main ingredient was milk – just ask 1959 Mr. Universe Bruce Randall.
In 1953, at the age of 20, Randall decided he wanted to become one of the strongest men on the planet. To do this, he figured he needed to become huge. Sporting a 203-pound Marine-hardened body, Randall started pumping iron and increased his calorie intake to 15,000 a day. Much of his calories came from milk, as he would consume an average of 8-10 quarts of cow juice a day, once drinking 19 quarts in a single day!
Randall eventually bulked up to 410 pounds and was able to do barbell curls with 228 pounds and a good morning with 685 pounds. Having crossed the strongman goal off his bucket list, Randall dropped 218 pounds in 32 weeks – nearly a half-century before the first episode of “The Biggest Loser” – and got in good enough shape to compete in the 1956 Mr. America. Fast-forward to today, and the dairy industry is promoting low-fat chocolate milk as the ultimate post-workout drink.
“Built with Chocolate Milk” is the most recent advertising campaign that promotes low-fat chocolate milk as the ultimate post-workout drink. One commercial spot features NBA star Klay Thompson who tells his fans, “I’m Klay Thompson and I’m built with chocolate milk. Nutrients to refuel, natural protein to rebuild, backed by science. After sinking long-distance shot after long-distance shot, Thompson finished the spot by tossing his empty chocolate milk bottle through a hoop – nothing but net! Should we believe Klay?
Many studies have been conducted on chocolate milk, such as by comparing it to a high-carb, post-workout drink. One 12-study meta-analysis published in the European Journal of Clinical Nutrition in 2018 concluded that chocolate milk “…provides either similar or superior results when compared to placebo or other recovery drinks.” But there are other issues to consider before rushing to the dairy section of your local market.
First, many people are allergic or intolerant to the lactose in milk. Unless it’s organic, commercial milk often contains added growth hormone and antibiotics. There is also little research to support the belief that low-fat milk is superior to whole milk and, in fact, can low-fat milk may increase circulating triglycerides -- one review even suggested that cow’s milk may increase the risk of prostate cancer. As for the chocolate, this gooey goodness often contains health-decaying high-fructose corn syrup that will create a large insulin spike that can cause sluggishness, along with a laundry list of health problems.
What are the components of a healthy post-workout shake? Whey protein is a good place to start as it provides a large array of amino acids for protein synthesis, improves insulin sensitivity, and its high thermic effect makes it beneficial for fat loss. Scooping in some carb power will help you restore muscle glycogen (although take it easy if fat loss is one of your goals), and electrolytes will improve water balance to rehydrate you. Oh, and scrap the raw eggs to avoid the risk of salmonella.
An alternative to whey protein is free form amino acids, especially for those who are trying to lose bodyfat. A 2012 study by Nutrition Journal found that these essential amino acids lead to increased fat loss and the preservation of muscle tissue during caloric restriction-based diets. Because they are already broken down and don’t contain lactose, free form amino acids are easier on the gut. Although many types of whey protein contain less lactose, especially whey isolate powders, some individuals who are lactose intolerance or lactose sensitive still have digestive issues with these products. If there is any concern about gut issues, free form amino acids are easier to digest because they are already broken down.
It’s a popular belief that protein should be consumed within an hour after a workout for optimal for muscle remodeling. However, a meta-analysis of 23 studies did not support this idea, and the researchers concluded that any positive effects observed in these studies “…were found to be due to an increased protein intake rather than the temporal aspects of consumption.” Solid food could certainly be consumed post-workout, but often it is difficult for the digestive system of some individuals to handle solid food immediately after a workout.
Is there any advantage to using slow-digesting proteins (such as casein) versus fast-digesting proteins (such as whey) for muscle and strength gains? One nine-week study involving 31 resistance-trained males sought to answer this question. The subjects performed a four-days-per-week workout of basic weight training exercises that involved a gradual decrease from 10-12 reps to 6-8, and from 70-75 percent of 1RM to 80-85 percent of 1RM. The subjects were divided into three groups, one using a fast-digesting protein, another a slow digesting protein, and another a mix. The amount of protein per drink was 20 grams. The researchers found no significant differences in strength gains, muscular endurance, or fat mass among the three groups. The takeaway is that the primary benefits of a post-workout shake come from increased protein intake, regardless of how long it takes to digest the protein.
Because it is easier to keep track of your macronutrients with protein powders, would multiple protein shakes rather than solid meals be a good idea to use on a strict fat loss diet? One popular diet prescribed just that, recommending the user consume 4-5 whey protein shakes a day for 28 days, along with fiber, supplements, and one solid meal a week. Bad idea. A low-calorie diet consisting of 4-5 protein shakes a day is probably lacking in essential nutrients and may cause issues with your gut. There is also the issue of motivating yourself to stay on such a diet and the challenge of maintaining your bodyweight after extreme, rapid weight loss.
Post-workout protein shakes appear to be here to stay. If used wisely, they can certainly be a boost to your training whether you are trying to gain muscle, get stronger, lose fat, or simply improve the quality of your life.