Phosphatidic acid (PA) is a phospholipid, a special type of fat that is a major structural component of all biological membrane systems. PA is composed of two hydrophobic fatty acid "tails" and a hydrophilic phosphate "head" which are joined together by a glycerol molecule. It's naturally occurring in the body, but can also be found in many soy and egg-based foods, including soy lecithin.
In addition to providing structural support for cell membranes, phosphatidic acid functions as an important signaling lipid in the body as well as being a necessary precursor for the synthesis of many other important lipids. 
That's great and everything, but what does it do?!
It's common knowledge that muscles grow in response to progressively lifting more weight, but do you know why?
It all traces back to one specific protein called "mammalian target of rapamycin" or mTOR. mTOR driven primarily from weight lifting has been dubbed "mechanically-induced mTOR signalling."
This eventually led researchers, and supplement companies, to find ways of possibly stimulating mTOR signaling through the use of specific ingredients, some of these have proven quite successful, as in the case of BCAAs.
Enter Phosphatidic AcidNot content with the simple fact that mechanical signaling of mTOR stimulated muscle growth, researchers dug deep until they knew every last detail of the process. (Don't worry we're not going to go overboard with the science here!)
A number of studies using images of muscle cells under contraction identified both the pathway and the compound (phospholipase D) that were directly responsible for mechanically-induced mTOR signaling. Researchers then determined that phospholipase D also degrades phosphatidylcholine into choline and phosphatidic acid. 
The benefits of choline are pretty well known already, but the researchers also determined that phosphatidic acid, directly activates mTOR!
Benefits of Phosphatidic AcidKnowing that PA directly activates mTOR, researchers then decided to test whether an isolated form of the compound taken via supplementation could similarly stimulate mTOR, and ultimately muscle growth.
And, lo and behold, phosphatidic acid has been proven in human trials to successfully activate mTOR and lead to a whole host of benefits including:
Greater Strength OutputThe initial human trial involved trained athletes that were given 750mg of phosphatidic acid daily for 8 weeks. During that time frame, athletes engaged in a strictly controlled weight lifting program and consumed virtually the same amount of calories throughout the study.
At the conclusion of the trial, the group consuming phosphatidic acid had increased their squat strength by 12.7%!  The same group also saw a 2.6% in lean body mass, but more on that in a second.
More Muscle, Less FatThe initial human trial piqued the curiosity of many around the scientific community and led to a follow up study on phosphatidic acid. This second study also lasted 8 weeks and was conducted using resistance trained athletes.
Again, the test group received 750mg of phosphatidic acid and at the conclusion of the 8 weeks, experienced significantly better lean body mass gains compared to the control group. On average, the phosphatidic acid group added 5 pounds of muscle compared to just 2.5 pounds for the control. 
The phosphatidic acid group also improved their leg press strength by 115 pounds, while the control group only added 70 pounds. As a "cherry on top," the test group also experienced increased fat loss vs the control group. The difference wasn't massive, as the PA group only lost 2.8 pounds compared to the 1.1 pounds the control group lost.
Now, that may not seem like a tremendous difference in fat loss, but any amount of fat loss is far and away better than no fat loss!
Reduced StressPhosphatidic acid has also been found to lower stress levels. In a study using phosphatidic acid derived from cow brains (yes, actual cow brains) in amounts ranging from 0 - 800mg. The group receiving the 400mg dose showed noticeable improvements in reducing cortisol levels. 
Now, this form of phosphatidic acid was made from cow brains as we've pointed out, and due to the random bouts of Mad Cow Disease that pop up from time to time. Due to this, chances are extremely rare that you'll find any phosphatidic acid supplements derived from cows. More likely than not, you'll find soy or egg-based PA supplements.
How Much Phosphatidic Acid?Based on the human studies showing increased gains in strength and muscle mass, as well as decreased fat, you want to consume at least 750mg phosphatidic acid daily.
Now, you can easily go and buy a standalone product that contains just the 750mg of phosphatidic acid, but a more economical route may be to purchase bulk Fearn Lecithin granules that contain a whopping 1.2g of phosphatidic acid, in addition to a truckload of other potent compounds like choline, phosphatidylcholine and phosphatidylserine!
The choice is up to you, but why not go the cheaper route and experience some fringe benefits as well!
When to take?Here's the interesting kicker with phosphatidic acid, the benefits are acute, meaning they occur after consuming the supplement, but that doesn't mean you have to consume it 30-40 minutes prior to workout like you do with you. typical pre workout. The research available has shown that plasma levels of PA increase 30 minutes after ingestions, peak at 1-3 hours and remain above baseline levels after 7 hours. 
So, you're well within your right to add it to your pre workout cocktail, but should you have a full pre workout meal (say, oatmeal or yogurt 1-3 hours before your pre workout) simply take your daily dose of phosphatidic acid and you'll be covered for up to 7 hours afterwards!
Wrapping It UpThe hunt for safe and natural ways to enhance the human potential for muscle growth is a never ending quest in the world of sports science. There are more than a handful of pretenders that have made headlines in recent years, but Phosphatidic Acid is a true contender.
Pushing heavier weights with bigger muscles and less fat -- we'll take that any day of the week!