Getting Your mTOR Running – How to Tell your Muscles it’s Time to Grow

14. 11. 2017

Muscle growth is a common aim for millions of athletes, so understanding the science behind the processes that trigger it is essential for anyone working in sports nutrition.

If you ask a biologist exactly how muscles get bigger and stronger, expect them to  talk about mTOR, which stands for “Mammalian Target of Rapamycin.” mTOR is a protein critically involved in the signalling mechanisms that tell your muscles when   it’s time to grow. Although it’s only one letter away from “motor”, it’s more like the digital ignition system that tells the motor it’s got work to do – it is the central controller of cellular growth in the muscles.



Three key factors stimulate mTOR. The first is mechanical stress: during a heavy workout, the muscles use mTOR to send a cellular message that they need help. The second are growth factors – such as growth hormones. And the third is nutrition – mTOR is highly dependent on the following dietary factors:

A surplus of calories – when you’re eating well, your body uses mTOR to tell your muscles, it’s a good time to grow.

Protein – you need to be getting enough protein to ensure your muscles have the amino acids they need for growth and recovery

Lipids – fats support the production and function of hormones that activate mTOR pathways


Three key factors stimulate mTOR


Any supplement that promises to increase the size and strength of muscles should in some way stimulate mTOR, and some of the most impressive results with supplementation have been achieved with members of the phospholipid family.

Phospholipids, including phosphatidylserine (PS), are a major component of cell membranes and play an important role in the body as biological messengers. Experts have speculated that they have the power to “send the body’s cells a louder message to ‘grow’!”

Phosphatidylserine, of which Sharp•PS®TM is a leading brand, is already well known in

sports nutrition for the range of benefits it offers. Studies have shown that intake of PS leads to improved performance, reduced recovery time, less muscle soreness, and reduced levels of cortisol.



There is also increasing evidence that PS plays a significant role in mTOR signalling. In one key study, researchers found that PS can “stimulate a robust increase in mTOR signalling” (Joy et al, Nutrition & metabolism. 2014).

This supports the findings of another study which found PS from soy “sufficient to induce an increase in mTOR signalling” (Gundermann et al, Journal of the International Society of Sports Nutrition, 2013).

In other words, it is clear that PS helps mTOR signalling, which in turn supports muscle growth. The most obvious consumer group to benefit from this are athletes, but increasing or maintain muscle mass is also an important target for other populations, including the elderly.