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Diet & Nutrition

A Legal Substance That Turns On Muscle Growth

It's really pretty easy:

  • mTOR is a naturally-occurring substance that regulates muscle growth.
  • If you activate mTOR by lifting weights, you grow more muscle.
  • Phosphatidic acid further activates mTOR.
  • If you take supplemental phosphatidic acid, you grow more muscle.

Okay, I just gave you the Dr. Seuss version of phosphatidic acid and its effect on mTOR and muscle growth. Here's the TED talk version, only less snooty:

mTOR, which is an abbreviation for the decidedly cool, Avengerish sounding term, "mammalian target of rapamycin," is a protein complex that acts as a signal interpreter of various "environmental cues," along with controlling protein synthesis. Things that activate the mTOR pathway include mechanical loading (e.g., weight lifting), insulin, and IGF-1.

Other environmental cues that also coerce mTOR into synthesizing protein include nutritional activators like protein (amino acids) and something called phosphatidic acid (PA), a naturally occurring phospholipid.

This mTOR pathway is in fact the major nutrient-sensitive regulator of growth in mammals and it's even been suggested that the regulation of mTOR by mechanical stimuli (again, weight lifting) is mediated by PA.

In other words, it's possible that weight-lifting induced muscle protein synthesis would almost be completely disabled without the presence of PA.

Given all that, it only makes sense that taking additional PA (whose presence in the diet is negligible) would lead to additional muscle growth (if all other factors like training and diet and rest are in order), and this is exactly what the bulk of the research has shown.


A study conducted by Hoffman et al., recruited 16 resistance-trained men. They either ingested 750 mg. of PA or placebo over the course of eight weeks while participating in a four-day per week split routine. The team found that PA increased subjects' 1RM squat (the most weight they could lift for one rep) by 40% and lean body mass (LBM) by 50% over placebo.

Joy et al. did a study similar to the one above, using a split group of 28 men who followed a three-day per week undulating resistance program for eight weeks. The big difference was that in this study, the participants were given 450 mg. of PA 30 minutes before their workout and another 300 mg. immediately post workout. The PA group gained a significantly greater amount of muscle (2.4 kilos, or 5.29 pounds) than the placebo group.

Andre et al. decided to test the effects of lower dosages of PA. They rounded up 28 men and divided them into three groups, one group receiving 250 mg. of PA per day, one group receiving 375 mg. of PA a day, and a third group that got placebo, or zilch.

Despite using far lower doses of PA than other studies, the team found a "likely positive effect" on lean body mass and cross-sectional area of the rectus femoris muscle in the thigh in both the 250 mg. per day and the 375 mg. per day groups. Even so, one wonders what they would have found if they had used effective doses of PA.

Escalante et al. recruited 18 strength-trained males and randomly assigned them to a PA-containing multi-ingredient supplement group or a placebo group. The men trained three times a week for eight weeks using an undulating resistance program.

All of the participants followed the same training program three days a week for eight weeks. They were tested in the following areas before the study began and after the study concluded:

  • 1RM Leg Press Strength
  • 1RM Bench Press Strength
  • Push-Ups to Failure
  • Vertical Jump
  • Pro-Agility Shuttle Time
  • Peak Power Output
  • Lean Body Mass
  • Fat Mass
  • Thigh Muscle Mass

Each were placed and monitored on the identical diet consisting of 25% protein, 50% carbohydrate, and 25% fat.

Here's what they found in the PA group and the placebo group after eight weeks:

As you can easily see, the PA group gained a significant amount of lean body mass, along with increasing their 1RM bench press and 1RM leg press (compared to the placebo group).

Gonzalez, et al. also studied the effects of PA and the results weren't impressive. But Gonzalez 'fessed up to several potential problems, things like lack of exercise supervision, possible poor dietary adherence, imperfect exercise selection for assessing maximal strength, the design of the exercise program, methods of assessing changes in muscle architecture, body composition, and training status of the participants. So, we can write that one off as a not-so-good study.

It's not often that a supplement has this much scientific research to support it. Overall, supplementing with PA led to impressive increases in strength, cross-sectional area of muscles, and lean mass in general, even though none of the studies used what this long-time lifter would categorize as "hardcore" workout programs.

As far as I can tell, all of them used some variant of the newbie three sets of this, three sets of that, three times a week program. Snore. Personally and anecdotally, though, I can tell you that the use of PA, when paired with a balls-out or semi balls-out training program, almost always led to results that were far superior to those described in the various PA studies.


How bioavailable is PA?

To make supplemental PA work, it must enter into the muscle cell and bind to mTOR. In can also work indirectly by converting to lyso-phosphatidic acid and attaching to the muscle cell membrane, which increases intracellular PA and in turn activates mTOR.

To achieve this, the PA must be unsaturated. Chemi Nutra, one of the industry's most innovative materials manufacturers, has been able to produce an unsaturated, orally bioavailable form of PA that exhibits an 8-fold increase of mTOR activation.

The levels of PA rise significantly within 30 minutes after dosing and stay elevated for 7 hours, but Biotest has further enhanced PA's bioavailability by combining Chemi Nutra's phosphatidic acid with Biotest's self-microemulsifying nutrient delivery system. The resultant product is named Micro-PA® and its degree of bioavailability is unsurpassed.

Does Micro-PA® have any side effects?

None of the subjects in any of the studies reported any side effects.

Is PA on any organization's banned drug/supplement list?

No, and neither will it lead to a failed drug test.

Can women use Micro-PA®?

Sure, but women with endometriosis should use caution as the condition is associated with high natural levels of PA. Whether taking supplemental PA would make matters worse is unknown, but, you know, better safe than sorry.

Can I increase intake of PA by eating certain foods or nutrients?

Sure, you can eat cabbage, which has higher levels of PA than the vast majority of foods. Given that the recommended dose of PA is 750 mg. and that the average cabbage has 0.5 milligrams of per gram, just eat approximately three pounds of cabbage and an entire bottle of Beano approximately one hour before training.

What's the best way to use Micro-PA®?

Take 750 mg. (6 capsules of Micro-PA®) approximately one hour before training. On non-training days, take 6 capsules when it's convenient, but preferably at or around the same time every day.


  1. Hoffman JR, Stout JR, Williams DR, Wells AJ, Fragala MS, Mangine GT, Gonzalez AM, Emerson NS, McCormack WP, Scanlon TC, et al. "Efficacy of phosphatidic acid ingestion on lean body mass, muscle thickness and strength gains in resistance-trained men," J Int Soc Sports Nutr. 2012;9(1):1.
  2. Joy JM, Gundermann DM, Lowery RP, J¨ager R, McCleary SA, Purpura M, Roberts MD, Wilson SM, Hornberger TA, Wilson JM. "Phosphatidic acid enhances mtor signaling and resistance exercise induced hypertrophy." Nutr Metab. 2014;11:1.
  3. Andre TL, Gann JJ, McKinley-Barnard SK, Song JJ, Willoughby DS. "Eight weeks of phosphatidic acid supplementation in conjunction with resistance training does not differentially affect body composition and muscle strength in resistance-trained men." J Sports Sci Med. 2016;15:532–539.
  4. Escalante G, Alencar M, Haddock B, Harvey P. "The effects of phosphatidic acid supplementation on strength, body composition, muscular endurance, power, agility, and vertical jump in resistance trained men." J Int Soc Sports Nutr. 2016;13(1):1.
  5. Gonzalez AM, Sell KM, Ghigiarelli JJ, Kelly CF, Shone EW, Accetta MR, Baum JB, Mangine GT. "Effects of phosphatidic acid supplementation on muscle thickness and strength in resistance-trained men." Applied Physiology, Nutrition, and Metabolism (ja). 2017.
  6. Li, J., Gao, Y., Guan, L., Zhang, H., Sun, J., Gong, X., ... & Bi, H. (2018). "Discovery of phosphatidic acid, phosphatidylcholine and phosphatidylserine as biomarkers for early diagnosis of endometriosis." Frontiers in Physiology, 9, 14.

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