Why m-TORC has no isoleucine or valine.
Posted on May 08 2026
Every BCAA tub on shelf has the same three ingredients: leucine, isoleucine, and valine. The marketing argument is which ratio they sit in. m-TORC isn't on that argument. The three aminos in m-TORC are leucine, glutamine, and glycine. There is no isoleucine. There is no valine. This article is about why.
The on-switch isn't "the BCAAs." It's leucine.
The branched-chain amino acids — leucine, isoleucine, valine — get grouped together in the supplement aisle because they share a structural quirk and a metabolic pathway. For the specific job of switching on muscle protein synthesis, they are not three equal players. Leucine activates mTOR — the kinase complex that, when active, has ribosomes translating amino acids into new muscle protein, and when inactive, doesn't. Isoleucine and valine are bystanders at this particular switch.1
If isoleucine and valine were merely inert, including them would be wasteful but harmless. They aren't inert. Leucine is transported into cells by a membrane carrier called System L — specifically the LAT1 transporter, which is the relevant one in the muscle tissue we care about. Isoleucine and valine use the same carrier. They compete with leucine for transporter slots. In the work by Yanagida and colleagues, the uptake of labelled leucine into cells was competitively inhibited by isoleucine and valine — but not by glycine or glutamine.2
Other BCAA products sell you a 2:1:1 ratio. We sell you 100% of the transporter slots used by something that does the work.
Cell swelling: the variable nobody talks about.
Once leucine is inside the cell and mTOR is on, the next question is what state the cell is in. Cells in a swollen state behave differently from cells in a shrunken state. This is one of the more under-discussed signals in cellular metabolism, and the Haussinger lab in Düsseldorf laid most of the groundwork on it in the 1990s. The summary, in one line: small fluctuations in cell hydration — cell volume — act as a separate, potent signal for metabolism and gene expression.3
Cell swelling increases protein synthesis. Cell shrinkage stimulates protein breakdown. The known anti-proteolytic effect of insulin — and of several individual amino acids — is transmitted in large part by their effect on cell volume. Insulin is the body's main physiological cell-swelling agent, but you don't want chronically elevated insulin: it does the wrong thing for inflammation, body composition, and metabolic health over time. So the question becomes: are there ways to cause cell swelling without leaning on chronic insulin?
There are two we can actually use. They're both in m-TORC.
Glutamine and glycine: how we get cells to swell without insulin.
Glutamine is taken up into cells by amino acid transport System N — a carrier that's not sensitive to nutritional state. You don't need to be fed for it to work; you don't need carbs alongside; you don't need a permission-slip from insulin. Glutamine moves in, and the cell swells for the duration of its presence.
Glycine is taken up by System A. It's a potent cell-swelling agent on its own, and especially so in a slightly fasted state — System A is up-regulated when the body is in a fasted nutritional state, which makes glycine roughly three times more potent at swelling cells fasted than fed. This matters in practical terms: m-TORC is taken intra-workout and between meals — both states in which System A is up-regulated and glycine is doing real work.
Both also have a more specific job to do, separate from cell swelling. Glutamine is the rate-limiting input for leucine uptake at the cell membrane. The bidirectional transporter SLC7A5/SLC3A2 — the one leucine uses to enter the cell — works by exchange: glutamine effluxes out of the cell, and leucine simultaneously enters. Without glutamine inside the cell to push out, leucine has nothing to swap against, and uptake is throttled.4 If you take leucine without ensuring glutamine is around, you blunt your own dose.
Glycine has a different job. Inflammation — the kind produced by hard training, ageing, or a high-stress life — blunts the anabolic response to leucine. The cell stops listening properly. In a 2016 study, mice given a pro-inflammatory stimulus failed to mount a protein-synthesis response to leucine; mice pre-treated with glycine before the same stimulus mounted a 51% protein-synthesis response on top of baseline.5 Glycine restores anabolic sensitivity to leucine in a body that's inflamed. Most adult lifters are inflamed.
How we dose m-TORC.
One scoop is 20g. The intra-workout dose is 20g in 1 to 1.5 litres of water, sipped through the session. The volume of water is not optional — cell swelling is a hydration story before it is an amino acid story, and a 20g scoop in 250ml will deliver fewer of the benefits we just spent the article describing.
The between-meals dose is 10g, taken roughly 90 minutes after breakfast and 90 minutes after lunch, in 100–500ml of water. This is for clients who want body-composition effects beyond the workout window — overweight clients, clients trying to gain muscle, anyone over 30 looking after their insulin sensitivity and protein-synthesis machinery between sessions.
One question that comes up: why not just sip m-TORC continuously through the day instead of dosing it in three chunks? Because the cells need to reset. Continuous leucine elevation eventually de-sensitises the mTOR pathway — the cells stop responding. Bolus dosing with a recovery window between maintains sensitivity, which keeps the signal sharp.6 "More" is not the right axis. "Bolus + window" is the right axis.
What's not in it.
No isoleucine or valine, for the reasons above. No additional EAAs, for the same reasons — protein-rich meals or full EAA blends in the workout window flood the cell with substrates that compete with leucine for transport, blunting the dose. m-TORC is a leucine-led intra-workout drink, and that means deliberately keeping the rest of the protein out of the bottle.
And no proprietary blend. Every gram of every amino acid in m-TORC is on the label, in numbers, not in a generic "Anabolic Matrix™" that hides the doses.
Closing.
The supplement aisle defaults to "more of the obvious thing." More leucine. More isoleucine. More valine. More flavours. More buzzwords. The biology defaults to "the right thing in the right amount, in the right state, at the right time." Three amino acids that work together at a cellular level — leucine doing the signalling, glutamine clearing the runway for it, glycine restoring its sensitivity in inflamed tissue — in a volume of water that lets cells swell to the state where the signal actually lands.
If you read your scoops carefully, you don't necessarily need m-TORC. You need a leucine-led intra-workout drink that respects what the receptors and transporters are actually doing. m-TORC happens to be one.
