I will address the optimal protein intake for people who regularly train(3x per week or more)—the optimal protein intake in terms of quantity and frequency for muscle gain or muscle preservation.
There are varying estimates out there about what is the optimal amount of protein for weight training individuals. Many supplement companies and fitness celebrities overestimate the optimal amount of protein. You will hear people such as Jim Steppani claim that you need 2 grams of protein per pound of bodyweight.
The answer to the question ‘how much protein should I take to maximize muscle gain?’ is not a simple one. Many variables influence your need for protein, such as age, gender, the intensity of training, frequency of exercise, body composition, and goals. The answer does not come down to an exact amount but instead in a range.
According to the most comprehensive meta-analysis on protein consumption to date, you can optimize muscle gain with 0.73-1.0 grams of protein per pound of LEAN bodyweight (fat-free mass). Estimate how much you’d weigh with little to no body fat and use that as your guide. You can do this by taking an educated guess on your body fat percentage and subtracting that from your total weight. If you want to measure your body fat percentage, you can use a DEXA scan, bod pod, skinfold calipers, hydrostatic weighing, or electrical impedance. Beyond this range, there is no additional benefit of extra protein for muscle growth.
However, suppose you are already lean and trying to preserve or even gain a little muscle while losing the last bit of fat. In that case, you might benefit by going up to 1.1 grams of protein per pound of body weight, according to a review from the International Journal of Sport Nutrition and Exercise Metabolism.
Overall we are left with the range of (0.73-1.1) grams of protein per pound of body weight. The vast majority of people do not need more than 0.73 grams per pound to maximize gains. The upper end of that spectrum can benefit people who are already lean but in a caloric deficit to get leaner, which I’m currently doing.
Can there be any benefit from extra protein?
Yes, but not for your muscles. Extra protein can help make weight loss easier. Of all the macros (carbs, fats, protein), protein is the most satiating, meaning it leaves you the fullest. For example, I could easily consume 1500 calories from cake and Icecream but would struggle to consume 1500 calories from lean chicken. Protein also has the highest thermic effect meaning it takes the most amount of energy for the body to break down. Up to 30% of calories from protein gets burned just from digesting it. At 30%, if you consume 800 calories from protein, you are left with 560 calories for the body to use.
According to IFB Pro Greg Doucette, five meals a day with protein maximizes protein synthesis. In that case, you are looking to eat every 3-5 hours. When I say meal, it doesn’t need to be a full-blown meal on a dinner plate. A snack or shake can count as one of your five meals.
Not every meal needs to have the same amount of protein. Say you targeted 150 grams of protein. You’d need an average of 30 grams per meal. One piece of chicken breast(181 grams) has 58 grams of protein. A portion of lean meat with every meal can easily get you there. You can calculate protein from various food sources to plan it out and see what works, even if your vegan or vegetarian. Use the protein food calculator tool. I use the nutrition labels, and from experience, I usually already have a good idea of how much protein a meal has just from looking at my food. Some meals could have 20 grams, and other meals can have 40 or more grams. It doesn’t matter as long as they collectively add up to 150 or more—no need to overcomplicate it. You can’t go wrong with going over. You only need to make sure you don’t fall short of your targeted daily protein intake.
I will emphasize that throughout the day and before you go to bed, you want slow-releasing protein and only use fast releasing protein such as whey and isolate around your workout if you choose to use it.
In short, we are left with (0.73-1.1g) grams of protein per pound of lean body-weight spread out into five servings throughout the day for maximum protein synthesis. Any additional protein will not help with muscle growth or preservation but can help you in your efforts to lose fat.