Protein Supplementation Increases Muscle Mass

Man training in gym

People who train for strength and/or muscle growth by lifting weights have long supplemented with protein in order to get the biggest gains possible from their exercise. Whey protein has been studied extensively for this purpose, with varying results. A new meta-analysis (a review of studies) has concluded that it indeed works and that protein supplementation increases muscle mass when combined with resistance training (weightlifting and similar exercise).

The analysis

The new meta-analysis is called A systematic review, meta-analysis and meta-regression of the effect of protein supplementation on resistance training-induced gains in muscle mass and strength in healthy adults, and among the authors are some very well-known names in this area.

The authors state their reasons for conducting the study:

Despite a large volume of work in this area, narrative reviews and even meta-analyses yield conflicting results as to the actual effectiveness of protein supplementation to enhance RET [resistance exercise training]-mediated gains in muscle mass and strength. This lack of agreement on the efficacy of protein supplementation is likely due to the use of divergent study inclusion criteria and inclusion of subjects with differing: ages, training statuses, total protein intakes, protein sources and protein doses. Thus, an evidence-based answer to the main question of the efficacy of protein supplementation, while previously reported, now appears to be controversial.

Without going into the details of how they conducted their study, they conclude that

Dietary protein supplementation significantly enhanced changes in muscle strength and size during prolonged RET in healthy adults. Increasing age reduces and training experience increases the efficacy of protein supplementation during RET. With protein supplementation, protein intakes at amounts greater than ~1.6 g/kg/day do not further contribute RET-induced gains in FFM.

In other words, adding protein in the form of whey, casein or other proteins causes a greater gain in muscle mass and strength than without protein supplements.

The average gain using extra protein over all of the studies looked at was 27% greater than without protein. That’s substantial.

The protein most often studied in relation to muscle gains is whey, although others such as casein and even plant protein concentrates have been studied.

An important caveat to the analysis is that beyond a total protein intake of about 1.6 grams per kilogram of body weight, protein supplementation does not result in further gains.

So, at least in part, protein supplementation works by increasing total protein intake.

Also in part, protein supplements work when to increase muscle mass when taken immediately before or after a workout, within an approximately 1-hour time window.

Protein requirements

Previous studies on protein requirements for muscle growth have found an upper limit of approximately 1.8 g/kg, beyond which further protein does not increase growth of muscle. The current study confirms this general limit at 1.6 g/kg.

The important lesson here for anyone using resistance training to increase muscle is that if you get less than 1.6 g/kg of protein daily, you are not optimizing your muscle growth.

Without sufficient protein, some of your weight training essentially is wasted, dissipated and not used for muscle growth for lack of sufficient protein. In effect, you’re leaving money on the table.

Whey protein

Whey protein is the best post-workout protein supplement for maximizing muscle growth. A whey drink of 20 to 30 grams of protein immediately before or after a workout can go a long way toward maximizing muscle gains.

The whey proteins that I’ve used and recommend are NutraBio and Bulk Supplements.

PS: Check out my Supplements Buying Guide for Men.

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  1. BC says:

    I thought that around 1.2g per kg bodyweight was previously said to be optimal, and one had to be careful not to consume too much protein as it the most thermogenic type of calorie, which is not good for aging. Has this changed? What are the sweet spot and upper limit now?

    • P. D. Mangan says:

      I’m not sure that protein’s thermogenic character is related to aging. Protein’s alleged effect on aging is through mTOR activation; however, at this point, no one knows whether and if so, how much protein is detrimental. The number in the article, 1.6 g/kg protein, is really an upper limit of protein requirements, and IMO it won’t accelerate aging. Chronically activated mTOR increases aging, and I doubt that protein alone will do that.

  2. Isaac Ohel says:

    I could only read the abstract. If you have access the complete article could you comment on the effect of age on efficacy. In other words, at what age are protein supplements a waste of money?

    • P. D. Mangan says:

      They did say that efficacy decreased with age and that protein worked best when combined with resistance training.

  3. Buffedd says:

    I have read the book and learned a lot of things, two thumbs up!!!

  4. eah says:

    Just wanted to post a link to a tweet about Jeff Bezos — maybe he’s a fan of yours Dennis:

  5. JP says:

    Iron, zinc, and magnesium are metals, but are needed at some level. We know that excess iron is bad for you. Is there a level of “excess” zinc or magnesium that is also bad?

    • P. D. Mangan says:

      Well, magnesium and zinc can be toxic when ingested at high levels, so yes. Kidney disease patients can have too high magnesium levels since they don’t get rid of it efficiently. I think it’s rather more difficult to get toxic levels of zinc and magnesium; iron is another story, since the body has mechanisms for grabbing it and never letting go.

  6. Ole says:

    JP, worry, more about the accumulation of cadmium, which serves no biological purpose in the body.

    • JP says:

      OK… but am I somehow ingesting cadmium without knowing it?

      • Bill says:

        Superphosphate which is used by many farmers ( especially here in Oz) to improve phosphorus level in the soil, can come naturally contaminated with Cadmium..

        But ‘super’ is prohibited in organic farming systems. It’s one reason for buying organic produce if it’s available and not too expensive.

        • Bill says:

          Here’s one research source that mentions this
          “The most recent systematic literature reviews and meta-analyses have indicated significant and nutritionally-relevant composition differences between organic and conventional foods. This included higher antioxidant, but lower cadmium and pesticide levels in organic crops, and higher omega-3 fatty acids concentrations in organic meat and dairy products. Also, results from a small number of human cohort studies indicate that there are positive associations between organic food consumption and reduced risk/incidence of certain acute diseases (e.g. pre-eclampsia, hypospadias) and obesity.”

          The Journal of Food & nutrition Research

  7. Ole says:

    No reason to worry, but certain foods contain larger amounts of cadmium than others. Excess cadmium can cause decreased kidney functon, neurologel issues and cancer. You can ‘Google’ which food to decrease the cosumption of. The minerals you mention above are crucial for proper cellular function, and assuming you are eating a healthy diet, you are unlikely to be defecient.

  8. Daniel Antinora says:

    1.6 g/kg

    Lean mass? Total body weight?

  9. Danny says:

    I’m not buying that whole drink/consume a protein shake post workout in fact I’ve seen more gains by not eating anything after I’m done working out I usually wait an Hour then eat some eggs or steak etc.

    also when you eat food it takes time to digest so its the same with a protein shake its not going to go directlyto the muscle it has to digest first. There is so much misinformation on this topic,

    I hear it all the time: drink a shake and boom its already in the muscle. Nope

    I also wonder if drinking protein shakes is actually beneficial at all and how much of it is absorbed since it’ll pass quickly through the GI tract.

    I stopped buying powders Feb of this year and never Have I been stronger.

    eat food forget powders its a con and a gimmick.

    I love your website and the info you offer

    much love and god bless

    • Nick says:

      I think the idea is that whey powder doesn’t need to digest much, and so can be absorbed very quickly, especially on an otherwise empty stomach.

      Interesting to learn you’re experiencing differing results; the science (as PD reports) and generations of bodybuilders say otherwise. Reseach also shows it helps with recovery.

  10. Bruce says:

    See Layne Norton’s research on Leucine content of meals and it’s relationship to muscle protein synthesis. In short, MPS rises dramatically when leucine content of a meal exceeds 2g and there isn’t much increase after 3g (for say, a 75kg athlete). 3g of leucine is about 30-40 g of protein depending on source (milk is high in leucine, chicken/fish is lower). Also there’s a “rebound effect” where until your blood amino acid levels lower, additional protein meals don’t stimulate MPS. This time is 4-6 hours. So eat 30-40 grams of protein every 4-6 hours (3-5 meals per day). This seems consistent with the 1.6g/kg advice.
    Also, see this article which also seems consistent with the leucine hypothesis:

  11. Bruce says:

    PS, I have followed this protein advice (3 meals a day with 3g of leucine) and have gotten to a 500-lb deadlift at 43 y.o. and 170 lbs body weight.

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