The recommended daily allowance (RDA) of protein is 0.84 g/kg for adult men. This means a 75 kg adult male will require 63 g of protein per day. Bodybuilders will require higher protein intakes than those who do not train so much.
What the Studies Say
A study by the Department of Kinesiology, McMaster University in Canada found that protein intakes of 1.3-1.8 g/kg/day, consumed as 3 to 4 isonitrogenous meals will maximize muscle protein synthesis. 4 isonitrogenous meals simply mean that all 4 meals should have the same protein quantity. In other words, you need to divide your total protein quantity into 3 or 4 equal portions to have at each meal.
Another study by the Sports Performance Research in New Zealand found that bodybuilders respond best to consuming 2.3-3.1 g/kg/day. So between these two studies, we are looking at a large window of 1.3 to 3.1 grams of protein/kg per day. So how much protein should you really take?
As far as bodybuilders are concerned, the recommended protein intake is not a constant. It varies according to targets and performance. Are you a beginner? Are you getting ready for a bodybuilding competition? Are you focusing on muscle growth and strength or is your focus on weight cutting while retaining muscle? As a bodybuilder, you must be familiar with the terms bulking and cutting. The primary goals of bulking include building muscle, increasing strength, and for some people, this includes gaining weight. The goal of cutting in bodybuilding is all about losing body fat and getting leaner.
Protein Intake During the Muscle Building Stage (Bulking)
According to research from the University of Arkansas for Medical Sciences, “the composition of diets for bodybuilders should be 55-60% carbohydrate, 25-30% protein and 15-20% of fat, for both the off-season and pre-contest phases.” The researchers noted that bodybuilders normally work on increasing their muscle mass during the off-season (when there are no competitive events), which usually constitutes the majority of the year.
The bodybuilder needs to ensure he has a positive energy balance so that extra energy is available for muscle synthesis. Having sufficient carbohydrates, about 55-60% of total energy intake, helps maintain the training intensity. Sufficient protein ( about 1.3 to 1.8g/kg) is also needed to provide all essential amino acids for protein synthesis.
Protein Intake During Calorie Restrictions (Cutting)
About 6 to 12 weeks before a competition, most bodybuilders try to reduce the body fat levels to very low levels while attempting to retain their muscle mass. So in a pre-contest phase, bodybuilders need to get into a negative energy balance wherein the body fat can get oxidized. Though overall calorie intakes, especially from carbs and fats are reduced dramatically, it is necessary to maintain a relatively high protein intake to reduce muscle loss.
The Arkansas research team found “evidence that a relatively high protein intake (approximately 30% of energy intake) will reduce lean mass loss relative to a lower protein intake (approximately 15% of energy intake) during energy restriction.” The researchers from the earlier mentioned Canadian study noted that “increased levels of protein consumption, as high as 1.8-2.0 grams per day is advantageous in preventing muscle losses during periods of calorie restrictions aimed at fat loss.”
Body Weight Considerations
As a reference point, let’s take into consideration the ideal weight of a 5’8” man – it ranges from 125 to 163 pounds (56 to 73 kgs). But at 163 pounds, he’s bound to be looking plump, not muscular. His weight is coming from fat, not muscle.
Image: Steve Reeves
According to legendary bodybuilder Steve Reeves’ book on Building the Classic Physique the Natural Way, his base model for a serious bodybuilder stands 6’ tall and weighs about 200 pounds. The ideal weight increases by 10 pounds for every inch above that and vice versa. A male 5’8” male would be aiming for a muscular 160 pounds with Reeves’ chart.
Keep in mind that Reeves played Hercules in the 1950 movies and his concept of how bodybuilders look is quite different from what you may see on stage today.
Image: Larry Scott
The winner of the first Mr. Olympia contest in 1965, Larry Scott was 5 feet 8 inches tall and he weighed in at 205 pounds.
Image: Ronnie Coleman
Close to thirty years later, Ronnie Coleman won the same title from 1998 to 2005. He was 6 feet tall and competed at 300 pounds. In competitive bodybuilding, the pros seem to be getting heavier than ever. But if you want to look like the Golden boy Larry Scott or the Herculean Steve Reeves, aim for the weight ranges mentioned in Steve’s book.
The Simple Answer to “How much Protein?”
For those of who are looking for a straightforward answer, I’d say having about 1.5 to 2 grams of protein per kg of your body weight/day constitutes a high protein diet that is helpful for bodybuilders. You can up this to 2.5 to 3 grams during your weight cutting phases, while lowering your carb and fat intakes, to lose body fat and reduce muscle loss.
Let’s calculate how much protein a bodybuilder of height 5’8 weighing 160 pounds, needs. 160 pounds is approximately 72 Kgs. At 1.5 to 2 grams per kg of body weight, that’s – 108 to 150 gms of protein a day. For 4 isonitrogenous meals, this works out to roughly 30 to 40 gms of protein per meal (4 times a day). Make sure two of these meals are timed before and after your workout to ensure maximum muscle synthesis. Now that you know the ‘why’, ‘what and ‘how much’ regarding protein intake for bodybuilders, let’s take a deeper look at ‘when’ to eat the protein, for maximum bodybuilding impact.