AICAR
The 'exercise in a vial' from a famous mouse study: it flips the switch training flips. Proven in mice, banned in sport, unproven in people.
What it is
AICAR turns on AMPK, the energy sensor your muscles switch on during a long run, so your cells burn more fat and sugar and build more mitochondria without the run. In mice that meant 44 percent more endurance with no training. In people it has only ever been given by IV drip during heart surgery, so what a daily shot does for your fitness is a guess.
The people who try it are endurance athletes and metabolic tinkerers who want more fat burned per mile and better blood sugar handling, and who are not drug-tested, because AICAR has been on the WADA banned list since 2009, the year after the mouse study made it famous. It is not for anyone whose main goal is muscle, since the pathway it turns on tells muscle to stop building and start conserving. And it is not a weight-loss drug: it does nothing to appetite.
Honest expectation: most people feel nothing obvious. Some report easier long sessions and a steadier energy level after two to three weeks, and a small drop in waist or fasting glucose over an 8-week run if their diet is in order. Nobody has measured any of that in humans. If you expect the mouse result, a dramatic jump in endurance without training, you will be disappointed; mice got it at doses no one injects into a person.
Our doses are 1 mg to start, 3 mg standard and 5 mg at most, once a day subQ, for 8 weeks, then about 4 off. The break is caution about running it nonstop, not a tolerance reset: there is no human dosing data, and it drives the same energy switch as hard exercise. A 50 mg vial in 2.5 ml is 20 mg/ml, so 3 mg is 15 units on an insulin syringe. Cost is the practical catch: a 50 mg vial is about 17 days at 3 mg and 10 days at 5 mg, so an 8-week standard run is three to four vials, which makes it one of the pricier things to run for an effect you probably cannot feel. The mistake is running it for muscle gain alongside a bulk, where chronic AMPK activation works against you.
The evidence is a famous mouse study and a lot of cell work. In 2008 untrained mice on AICAR ran 44 percent longer, with more fat-burning fibres and mitochondria; the finding was real and repeated. In humans, AICAR (as the drug acadesine) was infused during heart bypass surgery in large trials, which tells us high IV doses are tolerated short-term with raised uric acid and lactate, and tells us nothing about daily shots for fitness. There is no human study of endurance, fat loss or blood sugar with AICAR. It is not approved for anything.
If you want the exercise-mimetic idea with a better profile, MOTS-c has small human data and is the more common choice; SLU-PP-332 is the other AMPK-adjacent experiment, with even less behind it. For fat loss, nothing here beats a GLP-1, and 5-Amino-1MQ is the oral option in this group. Skip AICAR entirely if you have gout or kidney stones, since it raises uric acid, and if you compete in anything tested.
What people use it for
Endurance without training
Early daysThe 2008 study that made it famous: sedentary mice given AICAR for four weeks ran 44 percent longer than untrained controls, with more oxidative muscle fibres and more mitochondria. It has been reproduced in rodents. No human endurance study exists, and the doses used in mice are not what anyone injects.
Fat burning and blood sugar
Early daysIn animals and in muscle cells, AMPK activation by AICAR increases fat oxidation and glucose uptake into muscle independent of insulin. This is the mechanism behind the fat-loss hopes. In people it has never been tested for this, and the appetite side is untouched, so the effect on your weight would come from training, not the shot.
Insulin sensitivity
Early daysRodent models of insulin resistance improved on AICAR, and the pathway overlaps with how metformin works. People with prediabetes sometimes try it on that basis. The human data that exists is from a totally different setting, so this is plausible and unmeasured.
Human safety data from heart surgery
Early daysAs acadesine, AICAR was infused during coronary bypass surgery in large trials to protect the heart. It was tolerated at high IV doses for a short time, with raised uric acid and lactate the main findings. That is the only human exposure data, and it says nothing about weeks of daily subQ dosing for fitness.
How people use it
Safety, in brief
Things people sometimes notice
- A sore spot where you inject
- Mild nausea or a flat, tired feeling in the first week
- Nothing noticeable, which is common
The full picture — stop signs and who should talk to a doctor first — is on the dosing guide.
Sources
The labels and studies behind this page. Each link opens the original on PubMed, DailyMed or ClinicalTrials.gov.
- AMPK and PPARdelta agonists are exercise mimetics
- Intravenous AICAR administration reduces hepatic glucose output and inhibits whole body lipolysis in type 2 diabetic patients
- Long-term AICAR administration reduces metabolic disturbances and lowers blood pressure in rats displaying features of the insulin resistance syndrome
- Effects of acadesine on myocardial infarction, stroke, and death following surgery. A meta-analysis of the 5 international randomized trials. The Multicenter Study of Perioperative Ischemia (McSPI) Research Group