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Protein timing for muscle building and strength

Posted on Tuesday, 8 January, 2013 by anthony

A recent review looked at the effect of protein timing on muscle building and strength in weight training athletes. Here’s a brief summary of the review:

Recommended protein and calorie intake for muscle building

To maximize muscle hypertrophy weightlifters should consume 1.2-2.0g protein and > 44-50 Calories per kg of bodyweight.

Leucine and muscle building

Leucine is one of the branched chain amino acids (BCAAs) and has been shown to have a significant effect on rates of muscle hypertrophy. In fact it is believed that Leucine may be the sole stimulator of muscle protein synthesis and appears to be nearly as effective for stimulating rates of muscle protein synthesis as the consumption of all of the BCAAs. Accordingly it is important that foods or protein drinks contain adequate amounts of leucine to stimulate muscle protein synthesis. It is currently recommended that ~3-4g of leucine are consumed per serving.

Best types of protein for muscle building

There are four main protein sources available to athletes: 1) Milk Protein; 2) Casein Protein; 3) Whey Protein; 4) Soy Protein

Each protein source can be scored on its bioavailability (BV) and protein digestibility corrected amino acid score (PDCAAS).

1) Milk Protein – a highly bioavailable protein source consisting of 80% casein & 20% whey that provides all of the essential amino acids (EAAs). It has good bioavailability with a BV of 91 and a PDCAAS of 1.00. The researchers state that milk protein is a readily absorbed protein source, that promotes muscle protein synthesis and tissue repair.

2) Casein Protein – the main protein found in milk it contains all the essential amino acids (EAAs). It is less bioavailable than milk protein with a BV of 77 and a PDCAAS of 1.00. Casein protein provides a more sustained release of amino acids due to the way it clots within the stomach.

3) Whey Protein – like milk and casein protein it contains all the essential amino acids but has greater bioavailability with a BV of 104 and a PDCAAS of 1.00. The researchers state that whey protein has excellent bioavailability that leads to rapid increases in rates of protein synthesis.

4) Soy Protein – contains all the EAAs but has a lower bioavailability than milk, casein or whey protein with a BV of 74 and PDCAAS of 1.00.

The researchers conclusions on protein intake for muscle building and strength

  • Consuming protein supplements either before or after a workout leads to improved recovery, lean body mass, physical performance, muscle hypertrophy and strength.
  • Whey protein is more effective than casein protein in the development of muscle strength.
  • Fat free milk consumed post workout (500ml of fat-free milk) is effective at increasing lean body mass, strength, muscle hypertrophy and lowering bodyfat.
  • Milk protein is superior to soy proteins for both lean body mass and muscle hypertrophy.
  • Consuming protein increases the rate of anabolism (muscle building) for approximately 3hours with peak rates of anabolism occurring ~45-90minutes post consumption. There is therefore only a limited time period post exercise in which to consume protein and maximize the rate of anabolism. In view of this whey protein is considered a good protein source due to its high bioavailability and rapid digestibility.
  • When consumed after exercise whey protein is more effective when combined with a fast acting carbohydrate like maltodextrin or glucose.
  • The consumption of essential amino acids (EAAs) appears to be more effective at increasing protein synthesis before exercise, particularly when combined with dextrose.


Stark M, Lukaszuk J, Prawitz A, and Salacinski A (2012) Protein timing and its effects on muscular hypertrophy and strength in individuals engaged in weight-training. Journal of the International Society of Sports Nutrition 2012, 9:54

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