Does collagen build muscle mass?

What the yes trials measured, and what fat-free mass actually is

Does collagen build muscle mass is a question the shelf answers with three trials and the honest page answers by asking what those trials measured, because the whole disagreement between the tub and the textbook lives in the difference between two phrases that sound alike, fat-free mass and muscle mass, and a lifter who learns the difference once reads every body composition claim differently afterwards. The three trials are real: randomised, placebo-controlled, twelve weeks of resistance training in older men with sarcopenia, in untrained younger men and in trained younger men, with 15g a day of collagen peptides against a placebo, and in each the collagen group gained more fat-free mass, with more strength in some, which is the finding the shelf prints. The measurement in each was fat-free mass by bioelectrical impedance or dual-energy X-ray absorptiometry, and fat-free mass is, as the name says, everything in the body that is not fat. Most of it is water, around seventy percent of fat-free mass, which shifts by litres with hydration, with glycogen, which binds three grams of water per gram and rises with carbohydrate intake and training, and with the water that any protein feeding draws into tissues. The rest is bone, the organs, the blood, the skin, the connective tissue of tendons, ligaments, fascia and the matrix inside muscle, and finally the contractile protein of the muscle fibres themselves, which is what a lifter means by muscle and which is a minority of the total. Fat-free mass can therefore rise without a single muscle fibre growing: a litre more water is a kilogram of fat-free mass, more glycogen is more fat-free mass, and more connective tissue or skin is more fat-free mass, all invisible to bioimpedance, which estimates fat-free mass from how electricity travels through body water, and all counted as lean by absorptiometry, which cannot tell contractile protein from the matrix around it. The honest page does not say this is what happened in the three trials, since nobody measured, but it says what the design allows: a protein that is a third glycine, that feeds connective tissue and skin and whose own trials show instrument changes in skin at 2.5g, given at 15g a day to people whose baseline protein was often below target, against a placebo of silica that supplied no protein at all, could plausibly raise fat-free mass by routes that are not muscle, and the trials cannot distinguish that from muscle growth because they did not look at muscle.

What measures muscle itself, what those measurements found, and the honest position for a lifter

What measures muscle itself is a shorter list and a more expensive one, which is why the collagen trials did not use it. Muscle protein synthesis is measured directly by infusing labelled amino acids and sampling muscle to see how fast new contractile protein is being built, the gold standard for whether a protein feeding builds muscle; fibre cross-sectional area is measured by biopsy, which shows whether the fibres themselves have grown; and muscle thickness or volume is measured by ultrasound or MRI of the muscle, which shows the muscle and not the water around it. The collagen literature has the first of these and it is unambiguous: in the randomised comparisons that gave whey or collagen peptides at matched protein doses and measured muscle protein synthesis, whey switched synthesis on and collagen did not, in young adults and in older adults, a result that follows from collagen's three percent leucine failing to reach the threshold that triggers synthesis and from its missing tryptophan leaving nothing complete to build with. The literature has none of the other two for collagen: no trial has shown bigger muscle fibres on biopsy or thicker muscle on imaging after collagen, so the direct evidence for collagen building muscle is a synthesis result that says it does not and a silence where the fibre and imaging results would be. Reading the two kinds of evidence together gives the honest answer. Collagen may add fat-free mass, as extra protein of any kind does in under-fed trainees and as a connective tissue protein might by routes that are not muscle, and the three trials are consistent with that; collagen does not build the muscle the question means, the contractile protein in bigger fibres, because it cannot switch synthesis on and nothing has shown it adding fibre, and the shelf's phrase builds muscle mass borrows the credibility of a measurement that does not measure muscle. The honest position for a lifter follows: muscle mass is built by resistance training and complete protein at 1.6 to 2.2g per kilogram with each meal clearing the leucine threshold, from whey, dairy, eggs, meat, fish, soya or a complete plant blend; collagen's grams are not counted towards that figure, its calories are counted in the energy total, and it is taken beside the complete protein for its own reasons, the skin trials at 2.5g and above, the joint trials at 5 to 10g, the tendon protocol at 15g with vitamin C an hour before loading, where its one indirect muscle rationale lives, the connective tissue the muscle pulls through, a proteomic study's mechanism with no outcome. The UK register agrees with the measurement: protein's sentence, contributes to a growth in muscle mass, is lawful on a collagen tub as a source of protein by energy and hollow in substance, because the evidence behind it is complete protein. The worked example is stated on its true terms: two capsules, 1200mg hydrolysed type 1 marine collagen with 12mg vitamin C at 15% of its reference value plus zinc, 120 for £16.99 at 28p a day, lab tested and UK made, the zinc carrying its contribution to normal protein synthesis, the collagen counting for nothing towards a protein target and making no muscle claim. Does collagen build muscle mass: it may build fat-free mass, which is a different number, and it does not build muscle, which is the number the lifter wanted.

What to check on the label