What helps rebuild connective tissue?

Walking the building site: the architect, the crew and the schedule, and why nothing is built on a site with no signal

What helps rebuild connective tissue is a question built on a construction metaphor, and the honest page takes the metaphor more seriously than the shelf does, by walking the building site and asking who does what, because a rebuild has five roles and the shelf sells exactly one of them while implying it sells the lot. The first role is the architect, and on a connective tissue site the architect is the signal. A tendon's, a ligament's or a bone's cells do not build on their own initiative, any more than a crew turns up and starts laying bricks on an empty plot; they build in response to instruction, and the instruction is the mechanical strain passing through the tissue. A tenocyte senses the stretch of the collagen fibrils around it through its membrane and the connections between cells, and answers with the synthesis of new collagen, the enzymes that remodel old matrix and, over time, the alignment of new fibrils along the direction of the strain; an osteoblast builds bone where the skeleton is loaded and an osteoclast removes it where it is not; a fibroblast in a healing ligament lays its fibrils along the line the scar is gently pulled in. Growth factors and hormones are the architect's assistants, modulating how strongly the cells respond, which is why oestrogen loss at menopause and the anabolic hormones of youth matter, but the architect is strain, and a site with no architect does not build. That is the finding the immobilisation experiments made unarguable: an unloaded tendon drops its collagen synthesis below baseline within days, an immobilised ligament loses a third of its stiffness in weeks, a bed-rested bone loses density monthly, an unloaded cartilage thins, and in each case the crew has not downed tools for lack of materials, since the animal and the person were fed throughout, but for lack of instruction, so that the site is not waiting but demolishing. The second role is the crew, the cells themselves, fibroblasts, tenocytes, osteoblasts and chondrocytes, and the honest page gives them two properties that the metaphor makes obvious: they build only what the architect specifies, so that a stronger signal, a heavier and more progressive load within what the tissue can bear, is the only way to a bigger build; and they build at their own pace, set by how fast they can synthesise, secrete and organise matrix and by how fast the old matrix can be taken down, which no delivery of materials hurries, since a crew with ten lorries of bricks lays bricks no faster than a crew with two. Repair performed by cells and not by capsules is the principle set out on the connective tissue repair page, and the building site is that principle with its roles named. The third role is the schedule, which is the tissue's turnover and the crew's pace together: weeks for muscle, which is why a reader sees their quadriceps change in a month; months for tendon and ligament to remodel to a new load; a year or more for the scar across a torn ligament or tendon to mature from small type 3 fibrils toward large aligned type 1; six to twelve weeks for a fracture's callus to bridge and months more to remodel; and nobody shortens a schedule set by cell biology, with the levers all being ways of not lengthening it. The regeneration ledger, which says which connective tissues can rebuild to the original and which only to scar, is on the regenerate connective tissue page, and it is the planning permission that decides what the site can ever become.

The materials and the inspector, why the lorry is never the bottleneck on a fed site, what the shelf is selling, and the worked example

The fourth role is the materials, and it is the one the shelf sells, so the honest page spends its time here. The materials for a connective tissue rebuild are the amino acids that collagen and the rest of the matrix are made from, glycine, proline and lysine above all, with hydroxyproline and hydroxylysine made on site from proline and lysine by the enzymes that need the cofactors; and the cofactors themselves, vitamin C for the hydroxylases that let the collagen chain fold into its stable helix, zinc for the enzymes that remodel old matrix, copper for lysyl oxidase that cross-links the new fibrils, manganese for the enzymes that build the proteoglycans of the matrix. Every one of these is needed, and the question for a building site is never whether materials are needed but whether they are short, and on a fed site they are not. A reader eating adequate protein, around 1.6 to 2 grams per kilogram if training hard and somewhat less otherwise, has an amino acid pool that every meal refills, from which fibroblasts draw glycine and proline whether the meal was eggs, chicken, lentils or a scoop of collagen, since digestion strips every protein to the same pool and the body makes glycine and proline itself as well as eating them; the glycine budget argument, that the body may need a few grams more glycine a day than it makes plus eats, is examined on the collagen build connective tissue page and does not change the site's picture, since no trial has shown a fed person's rebuild limited by glycine. A reader eating any fruit or vegetables has vitamin C at saturation for the hydroxylases, and a varied diet supplies zinc, copper and manganese to the sufficiency that is all the enzymes can use. So the lorry is never the bottleneck on a healthy site, and more lorries, a scoop of collagen on top of a sufficient diet, deliver bricks to a yard already full, where they are used for energy or excreted as urea within hours. The lorry is the bottleneck only on a site that is short, which is a real case and not the shelf's: a reader under-eating for their training, which the sports medicine consensus lists as a cause of soft tissue injury; a reader eating no fruit or vegetables, who is on the climb of the vitamin C curve; an older reader whose appetite has fallen and whose protein intake with it; a reader recovering from surgery with a poor appetite. For them more protein and a varied diet are the help, and collagen is protein and counts, at 1200mg a trivial amount and at 15g a meaningful one. The fifth role is the inspector, and the honest page names it because the shelf never does: the strength test against the other side, the hop test, the clinician's stress test on a ligament, the morning-after pain rule on a tendon, which say whether the build has reached the specification and the tissue can be used, and which the calendar and the absence of pain, the two things readers use instead, are not, since pain leaves the site months before the build is done. What the shelf is selling, then, is materials to a site that is usually waiting for an architect: a reader whose tendon is not rebuilding because it is not being loaded, whose ligament is weak because it was in a cast, whose cartilage is thinning because they have stopped walking, is offered a lorry of glycine, and the lorry arrives at an empty plot. Collagen's protocol, read honestly, is a delivery timed to the architect's visit, 15g gelatin with vitamin C about an hour before a loading session having raised a synthesis marker in healthy men, and one small trial having added collagen peptides to fourteen weeks of training with a greater increase in Achilles tendon cross-section, a manufacturer-funded result awaiting replication; it is a lorry that arrives while the crew is working, which is the only time a lorry matters, and it moves no schedule. The worked example is a lorry stated as a lorry, 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, below the 15g protocol dose, carrying vitamin C's collagen formation sentence for cartilage and bones and no connective tissue claim of its own. What helps rebuild connective tissue: the architect, which is load, first and always; the schedule respected; the materials kept sufficient; the inspector consulted; and no lorry sent to a site with no architect.

What to check on the label