Tony Huge

Does RAD 140 Build Muscle? What the Research Says: Tony Huge’s Video Guide

Table of Contents

The biggest myth about RAD 140 is that it has never been tested in a human. It has, but the trial was in 22 women with advanced breast cancer, and it measured receptor activity and liver markers, not how much muscle a trained man can add. Tony Huge walks through that study, the 2025 rat data, the mouse frailty findings, and the LGD-4033 suppression trial to show what the research does and does not answer.

Video: Does RAD 140 Actually Build Muscle? Here’s What the Research Says. Published September 18, 2026. Watch on YouTube.

What the video covers

What “selective” actually means

Tony starts with the mechanism because the marketing rests on a misreading of it. RAD 140 is a selective androgen receptor modulator. It binds the androgen receptor, and in muscle that can regulate gene expression in a way that plausibly promotes growth. The appeal is obvious: an androgenic muscle signal without the side effects of high testosterone.

But the androgen receptor exists in many tissues, and the response depends partly on what is happening inside each cell, including which co-regulator proteins are working with the receptor. So “selective” does not mean the molecule only shows up where you want it. It means the pattern of activity can differ between tissues. Tony’s interest in the mechanism comes from exactly that gap: changing the molecule changes what it does, but calling that change an improvement requires knowing which effect improved and which side effects were actually measured. Less activity in a reproductive tissue in an animal does not answer questions about a person’s liver, hormones, or cardiovascular system.

The human trial nobody talks about correctly

Tony cites the first-in-human RAD 140 trial: 22 post-menopausal women with advanced breast cancer who had already received substantial treatment, given RAD 140 orally once daily at 50, 100, or 150 mg. The researchers were looking at drug exposure, tolerability, receptor activity, and whether the cancer responded. They confirmed androgen receptor activation in paired tumor biopsies and saw blood marker changes consistent with androgen activity. That matters, Tony says, because it establishes human biological activity beyond a whiteboard diagram.

What it does not establish is anything about muscle in a healthy trained man. Nobody in that trial was comparing gym programs. The liver findings are the part he wants people to sit with: AST elevations in 59.1% of participants, ALT in 45.5%, bilirubin in 27.3%. He adds a separate case report of a 24-year-old man who developed jaundice, itching, and abdominal pain after five weeks of what he said was RAD 140, with bilirubin peaking at 38.5 mg/dL and a liver biopsy supporting cholestatic injury. Tony flags the obvious uncertainty, that nobody verified what the product actually contained, but he does not use that to dismiss the signal.

The 2025 rat study, read carefully

The animal data is where the muscle question gets its best current answer, and Tony’s reading is deliberately two-sided. In a 2025 study, male rats on RAD 140 for 14 days showed increased muscle fiber size compared to no intervention. That is a positive finding for the anabolic mechanism. But when RAD 140 was added to a surgical overload model, it did not produce a clear additional increase in muscle mass compared to overload alone.

“Does the compound have an effect on muscle? This experiment provides support for that. Yes. Did it clearly add more muscle on top of loading stimulus in this experiment? That comparison didn’t establish an extra benefit.”

Tony Huge, 04:23

The method matters, and Tony spells it out. The overload came from surgery that forced remaining muscles to carry more load, not from a lifting program. The drug was delivered in drinking water with a target of 3 mg/kg/day and estimated intake of 1.8 to 2.5 mg/kg/day. So he refuses to use it in either direction: not to say RAD 140 does nothing, since a fiber effect was measured, and not to promise extra gains over resistance training, since the experiment did not show that and its loading model looks nothing like a gym.

A second animal study pushes the other way. Female mice given RAD 140 for 10 weeks at 5 mg/kg were tested on performance and recovery after repeated eccentric contractions. Strength after recovery was not better, frailty measurements were worse, and the authors reported higher mortality risk. Tony notes this is a different species, sex, dose, and duration from the rat study, so the two cannot be averaged into a human prediction. What can be said is that the animal literature contains both a growth signal and findings that make the functional benefit less certain.

Suppression and the label problem

Being a SARM does not guarantee natural testosterone stays put. The closest human data Tony can find is a trial of a different SARM, LGD-4033, in 76 healthy men given placebo or 0.1, 0.3, or 1 mg daily for 21 days. Testosterone decreased as the dose increased, while lean body mass went up. In Tony’s experience LGD-4033 is the more powerful muscle builder of the two, with more side effects, so he treats it as a directional comparison rather than a RAD 140 result.

Then there is the supply chain. Tony cites a chemical analysis of 44 internet products marketed as SARMs. In only 18 did the measured amount of active compound match the label, and some contained undeclared substances. That single finding contaminates every anecdotal report, including the liver injury case, because nobody knows what was actually consumed.

Cheat Sheet Pivot

What Tony reported and what the cited studies used, not a protocol for anyone else.

  • The human trial used 50, 100, and 150 mg once daily in cancer patients, and Tony’s takeaway from it is the liver marker profile, not a dosing reference.
  • The rat study targeted 3 mg/kg/day in drinking water for 14 days; the mouse study used 5 mg/kg for 10 weeks. Tony cites both as mechanism evidence, not as anything transferable to a person.
  • His own observation from years of watching RAD 140 in use: it seems better at improving performance, strength, endurance, and muscle power, than at producing raw muscle growth.
  • He assumes suppression is on the table for any SARM, based on the LGD-4033 dose-response data, and does not assume RAD 140 is exempt.
  • Because fewer than half of tested products matched their labels, he treats product verification as part of the risk calculation.

The compound-by-compound summary of SARMs and the rest of the catalog is in the Miracle Molecules Cheat Sheet. For the broader comparison of LGD-4033 and RAD 140, read the SARMs Masterclass: LGD and RAD Guide. For why Tony thinks about suppression from day one of any cycle rather than after it, see Protection Starts on Day One.

Where the evidence stops

Tony ends by describing the study that does not exist: trained adults on a consistent program, a verified compound, and measurements of muscle size, strength, hormone recovery, and adverse events with follow-up long enough to judge whether benefits or side effects persist. Nothing in the current literature does that. The human trial is in cancer patients. The animal studies disagree with each other and used delivery methods that do not resemble human use. The suppression data is from a different molecule.

RAD 140 is not FDA approved, and Tony frames everything in the video as educational analysis of published research plus his own perspective. The honest summary is that the mechanism is real, the human activity is confirmed, the liver signal is real, and the muscle question in trained men remains open.

Keep going

Companion articles like this one go out with every new video through the tonyhuge.is email list. The full SARM archive, including stacking discussions and the evidence behind each compound, lives at tonyhuge.is.

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