Daily protein requirements for strength trainees

Your daily protein requirement is not one neat, round number that works for everyone. If you train seriously, build muscle mass or prepare for competitions, the question becomes much more practical: body weight, calorie intake, training volume and recovery all come into play.

To be honest, I have wrestled with the same question for years: how much protein do you actually need? The short answer is that a bodybuilder who trains seriously may need at least 2.5 g per 1 kg of body weight during a muscle-building phase. This is not an arbitrary slogan but a conclusion backed by both practical experience and scientific articles published in 2004 and 2006.

Why do daily protein requirements vary so much?

The longstanding debate largely comes down to whether 1.5–1.7 g per kg of body weight is enough for muscle building, or whether someone who trains seriously should aim for a higher intake. By now, it is clear that a single number does not reflect real life very well. People train differently, eat differently and recover differently.

In their 2004 article, Tipton and Wolfe even suggested an upper limit at which protein could account for up to 40% of total calorie intake. This does not mean everyone should immediately rush to 40%. Rather, it means that some people, at certain times, may need far more protein than traditional recommendations would suggest.

Take a simple example. If you weigh 90 kg and consume 6400 kcal a day, getting 14% of your calories from protein gives you around 2.5 g per kg of body weight. If you weigh 70 kg with the same intake of 6400 kcal and protein still accounts for 14%, that works out to 3.2 g per kg of body weight. It is just 14% of total calorie intake, but the difference relative to body weight is substantial.

That is why it makes little sense to ask only: how many grams of protein per day? A better question is: what are your current training demands, body weight, calorie intake and recovery needs?

Your daily protein requirements depend on these factors

There is considerable room for variation in protein intake. The core of the original idea still holds: protein requirements are determined not only by your desire to build muscle mass, but by the whole picture of your training load and nutrition.

1. Total calorie intake.
2. How much aerobic training you do alongside strength training.
3. The use of various supplements that increase protein synthesis and create an anabolic environment, whether legal or illegal.
4. Individual differences.
5. Strength training itself.
6. A higher-than-usual protein intake may itself support protein synthesis, increase lean muscle mass and train your body to retain more protein.
7. Total daily training time.

1. Total calorie intake

Pellot and colleagues examined protein requirements at different calorie intakes: 2100 kcal–4200 kcal. The finding was straightforward and significant for athletes. As total calorie intake decreases, protein requirements increase.

At a calorie intake of 30 kcal/kg of body weight, 1.42 g of protein per kg was needed to achieve zero nitrogen balance. At a calorie intake of 45 kcal/kg, the protein requirement for maintaining nitrogen balance was 0.87 g/kg. At a calorie intake of 60 kcal/kg, 0.32 g per kg of body weight was needed to achieve a nitrogen balance of 0.

Why does this matter in bodybuilding? Preparing for a competition often means eating in a calorie deficit. You need to lose fat while retaining muscle. This is precisely when protein requirements may rise. The same applies if you keep your fat and carbohydrate intake low year-round because you want to look leaner all the time.

2. Strength training combined with aerobic training

Strength training alone significantly increases protein requirements (1). Adding aerobic training may increase them further. Lemon (2) has emphasized that, through amino acid oxidation, aerobic exercise can increase protein requirements even more than many people who strength train realize.

Think of a bodybuilder who does 2 hours of weight training plus 30–40 minutes of aerobic training. Their situation is different from that of someone who does a short gym workout three times a week and is otherwise largely inactive. The total training load matters.

Consolazio and colleagues studied 2 groups over 40 days as they combined strength training with aerobic training. One group consumed 1.4 g of protein per kg of body weight, the other 2.8 g per kg of body weight. The group consuming 2.8 g per kg had a significantly more positive nitrogen balance.

3. Supplements and the anabolic environment

There is no need to discuss the effects of anabolic steroids on metabolism at length here. It is clear that chemical assistance can alter protein turnover in the body, so someone using it may have different protein requirements from a natural athlete.

But the issue goes beyond anabolic agents. The original text also mentioned creatine, which may create a more favorable anabolic environment through hydration (1). ZMA, Tribulus Terrestris and β-HMB ( β-hydroxy β-methylbutyrate) were also listed. The idea is simple: if your body’s protein balance improves, you need enough protein from food to benefit from that improvement at all.

4. Individual differences

This is where things get especially practical. In some trials, participants were given, for example, 2 g per kg of body weight. Most could be in positive nitrogen balance on that amount, yet there were still 1–2 individuals in the group who barely reached a nitrogen balance of 0.

This means the same amount does not work equally well for everyone. One person may recover well on the same diet, while another sees their strength plateau, their sleep deteriorate and their muscle mass stall. In that situation, the training program is not always the issue. Sometimes the question is whether daily protein intake matches the actual training load.

5. Strength training itself

Lemon (2) and colleagues studied relatively inexperienced bodybuilders. At a protein intake of 1.35 g per kg of body weight, they were in negative nitrogen balance (N = −3.4 g). Positive nitrogen balance was achieved when protein intake reached 2.62 g per kg (N = +8.6 g).

Linear regression suggested that this group would have needed 1.7 g per kg of body weight just to reach a nitrogen balance of 0. Note that 1.7 g per kg of body weight was estimated to be only the maintenance threshold. If your goal is muscle building, rather than simply maintaining what you already have, it is understandable why more serious trainees end up consuming larger amounts.

6. Higher protein intake

A higher-than-usual protein intake may itself stimulate protein synthesis, increase quality muscle mass and lead the body to become better at retaining protein at higher intakes (1). Researchers have been studying this point for a long time, and it can be debated, but for you as a trainee, the principle stays the same: too little protein may limit progress.

7. Total daily training time

One weakness of many studies on protein requirements is that the participants were neither professional bodybuilders nor professional weightlifters. Researchers often study the average trainee at a set training load. But what about someone who trains for 3, 4 or perhaps even 5 hours a day?

During contest preparation, a day may include strength training, cardio, posing and sometimes a second cardio session. Classic studies (2, 5, 6) often examine schedules involving 3–4 strength training sessions a week, averaging 75 minutes each. McArdle and colleagues have also pointed out that research too often overlooks athletes who train for 4–5 hours a day or do 2 strength training sessions alongside cardio (3).

How do you work out your daily protein requirements?

The simple truth is this: do not start with the highest number. Start with your own circumstances. If you train moderately, eat enough calories and simply want to stay in shape, you do not need to overthink protein. But if your goal is muscle building, you train frequently and your calorie intake is low, protein requirements immediately become more important.

The original article made a strong claim: 5–6 strength training sessions a week, combined with 2–3 shorter cardio sessions, an active lifestyle and a muscle-building goal, may create a need for at least 2.5 g per kg of body weight. That is a large amount, but not illogical when you add up the total training load.

That does not mean everyone should immediately make protein 35–40% of their total daily calorie intake. Anywhere from 25% to 35% of total calories may also be perfectly reasonable for a natural bodybuilder weighing 110–120 kg, but this depends on body weight, energy expenditure, appetite, digestion and the phase of training.

In practice, look at three things. First, whether your strength is improving or standing still. Second, whether your body weight and what you see in the mirror are moving in the direction you want. Third, how well you recover. If muscle soreness lingers, your strength drops and your appetite is out of control, protein intake may not be the only issue, but it is one thing to check.

Practical tips for assessing your daily protein intake

Your daily protein requirements do not need to become a mathematical obsession. It is much more important that your food diary, body weight and training log tell the same story. If you record what you eat, how active you are and how your workouts go, you will have a clearer idea within a couple of weeks of whether your current intake is working.

If you are bulking, your calorie intake is high and you are recovering well, the same protein percentage may already provide a substantial amount in grams. If you are dieting, eating fewer carbohydrates and fats, and doing more cardio, the same amount may fall short. So what actually happens? Your body has to make up the shortfall from somewhere, and as an athlete, you want to avoid that coming at the expense of muscle.

A good starting point is to keep your protein intake consistent and change one thing at a time. Do not make drastic changes to your calorie intake, cardio, training volume and protein intake all in the same week. Otherwise, you will not know which change actually made a difference.

And one more thing: protein cannot make up for a poor workout. If you are short on sleep, your training is haphazard and your diet consists of whatever bites you happen to grab, no amount of chasing grams will fix the situation. Protein matters, but it works as part of the overall plan.

FAQ: daily protein requirements

Does everyone need 2.5 g per kg of body weight?

No. This intake is more appropriate if you train seriously, your goal is muscle building and your training load is high. With lighter training and a regular diet, your requirements may be lower.

Should you calculate protein intake as a percentage or in grams?

Both have their place. A percentage shows how much of your total calorie intake comes from protein, while grams relative to body weight give you a more practical way, as an athlete, to assess whether your intake meets the needs of your body and training load.

When do protein requirements increase the most?

Usually when strength training volume is high, aerobic training is added, calorie intake is low or the goal is to maintain muscle mass while dieting. Individual differences always remain.

Note: The original article was written as a brief overview because the topic was relevant to the author at the time and had attracted interest on the forum. Much more could be written on the subject, but the main point remains the same: when you train seriously, protein requirements are neither low nor the same for everyone.

References

1. Jacob Wilson and Gabriel J. Wilson. Contemporary Issues in Protein Requirements and Consumption for Resistance Trained Athletes. Journal of the International Society of Sports Nutrition. 3(1):7-27, 2006.
2. Lemon PWR, Tarnopolsky MA, MacDougall JD, Atkinson SA: Protein requirements and muscle mass/strength changes during intensive training in novice bodybuilders. J Appl Physiol 1992, 73: 767775.
3. McArdle, W.D., Katch, F.I., & Katch, V.L: Sports and exercise nutrition. Philadelphia, PA: Lippincott, Williams, & Wilkins Publishing Co; 1999.
4. Millward DJ. Macronutrient intakes as determinants of dietary protein and amino acid adequacy. Nutr. 2004, 134(Suppl):1588S-1596S.
5. Tarnopolsky MA, Atkinson SA, MacDougall JD, Chesley A, Phillips S, Schwarcz HP. Evaluation of protein requirements for trained strength athletes. J Appl Physiol. 1992, 73:1986-95.
6. Tarnopolsky MA, MacDougall JD, Atkinson SA. Influence of protein intake and training status on nitrogen balance and lean body mass. J Appl Physiol. 1988, 64:187-93.
7. Tipton KD, Wolfe RR. Protein and amino acids for athletes. J Sports Sci. 2004, 22(1):65-79.

Author: Janar Rückenberg

Source: https://turg.fitness.ee/et

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