Protein timing is a contentious topic. Some studies suggest that consuming protein at certain times of the day, such as after a workout, boosts muscle protein synthesis. If that’s so, it’s favorable for muscle growth. Other research suggests that it isn’t when you consume it; it’s whether you take in enough total protein. As long as you’re getting enough, it doesn’t matter. But protein timing may still matter. A new analysis suggests that getting a dose of protein just before bedtime may be beneficial if you’re trying to increase muscle protein synthesis.
Protein Before Sleep?
Dr. Tim Snijders, Assistant Professor at Maastricht University, spearheaded a study looking at the impact of pre-sleep protein on gains in muscle strength and size. In the study, 44 young and healthy men took part in a 12-week weight training program. Half of the guys drank a protein drink that contained 30 grams of protein and 15 grams of carbohydrates. The second drank a placebo drink without protein or calories. On the plus side, both groups gained muscle strength and muscle size. Their one-rep max on squats increased, and they developed greater quadriceps circumference. But the men who got the protein supplement before bed experienced greater gains in muscle size and strength.
Should you jump on board the bedtime protein bandwagon? There are some shortcomings in the study. For one, the difference might be due to the increased calories the men who drank the protein/carb drink consumed. Plus, the study didn’t look at whether consuming a protein supplement at other times of day would have the same effect. But this isn’t the first study to show that consuming protein before turning in at night might provide a muscle-building edge. And research points out another possible benefit.
Protein at Bedtime Might Help with Weight Control Too
In one small study, 11 healthy young men who drank a casein protein drink before bed had a higher rate of fat burning the next day. That would be helpful if you’re trying to lose weight. It’s a small study but suggests that drinking a casein drink at bedtime could aid in muscle protein synthesis and weight loss. There’s another possible perk too. A study found that taking 30 grams of casein, 30 grams of whey, and 33 carbohydrate grams 30 minutes before sleep elevated resting metabolic rate in healthy, young men.
According to research, consuming more total protein and protein at night may be especially important for older people who have anabolic resistance and don’t respond as well to protein’s signals to grow. In one study, eight elderly men got a dose of protein before bedtime. The other eight consumed a placebo. The guys who consumed the casein experienced greater muscle growth relative to those who got the placebo. Another meta-analysis found that a dose of protein at bedtime stimulates muscle protein synthesis and promotes muscle growth and repair.
What about Consuming Protein After a Workout?
You may have also heard that after a workout is an optimal time to consume protein. This is based on the idea of an anabolic window, a window period where your body can best make use of protein. Makes sense, doesn’t it? After a workout, your body goes into repair mode and will eagerly suck up those amino acids and put them to use. Your muscles are also depleted of glycogen, so adding carbs to the protein helps replenish muscle glycogen stores.
How quickly do you need to take in that protein snack or shake? Most people try to rush and get their protein within an hour of a workout. However, more recent research suggests that the anabolic window may be wider than most people think. It suggests that you can wait as long as two hours after a workout to consume protein and still get the benefits.
There are advantages to spreading your protein intake across the day, especially if you’re trying to lose weight. Meals and snacks with high protein content help suppress appetite. Plus, when you consume a high-protein meal, research shows muscle protein synthesis increases for up to 4 hours after a meal. It’s a strategy for staying in a positive nitrogen balance, meaning you build more protein than you break down.
How Much Protein Do You Need on These Occasions?
You might wonder how much protein you would need to consume at bedtime and after workouts to get the benefits. Research suggests that 30 to 40 grams is optimal. More than that is just excess calories. You don’t have to get your protein from protein supplements or shakes. In fact, whole food sources of protein are often cleaner, since studies show that some protein supplements are contaminated with heavy metals. In one study, 55% of those tested contained heavy metals.
If you do take a protein supplement before bedtime, casein is a good choice. Milk protein is made up of roughly 80% casein and 20% whey. Whey is “fast protein” because you absorb it rapidly. In contrast, casein is a “slow protein” because your gut takes it up slowly. This means casein keeps supplying amino acids for a longer period, unlike whey that provides a quick spike in protein availability. A slow protein, like casein, is better since you’re fasting during sleep. Having casein in your system helps prevent muscle breakdown.
The Bottom Line
Protein before bedtime? How about after a workout? If you’re trying to build muscle, you can make an argument for consuming 30 grams of protein at bedtime and within a few hours after a workout. In reality, there’s no downside to doing so. You don’t need a protein supplement, but if you take one, casein is the best choice at bedtime, whereas whey will quickly supply your muscles with amino acids. That may work in your favor right after a workout.
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