Myostatin: An Important Inhibitor of Muscle Building

On the quest to add lean mass and build muscle it is important to understand not only how to train properly, but also how to make the best of your physiology and hormones to boost your progress.

In this article you’ll learn about one particular element of physiology that can limit your ability to add muscle – myostatin 

Myostatin (GDF-8) is a transforming growth factor ß protein that inhibits muscle development and promotes catabolism of lean tissue (atrophy). It does this by targeting satellite cells that would otherwise allow proliferation of new proteins during the typical cycle of overload-adaptation. It essentially tells the brain when to stop adding more muscle – it works like an off switch for muscle gains. 

On rare occasions GDF-8 may be completely deficient. For a perfect example see that attached picture of cattle with a so called ‘double muscle’ mutation.

There’s also evidence that it could increase your body fat levels too, by decreasing leptin sensitivity (leptin is a hormone that decreases appetite and assists in regulating fatty acid oxidation)

Methods to decrease myostatin

• Resistance training can reduce GDF-8 expression by 30-40% over a 9 week period
• Take creatine in conjunction with resistance training- typical dosing strategy aiming for 14-28% increases in muscle creatine levels work well
• Ensure your vitamin D levels are sufficient
• GDF-8 increases with increased glucocorticoids so manage your cortisol levels- reduce psycho-physiological loads, sleep well, and keep your training sessions productive and as short as possible
• Try blood flow restriction training- this particular method of training has previously demonstrated noted reductions in GDF-8
• Ensure sufficient amino acids in the diet (consider whey and possibly HMB supplementation)

On a final note be aware of so called ‘myostatin inhibitor’ supplements- a lot of these have no empirical evidence to back up their claims and for those that have been studied the research methodologies were somewhat…flawed!