In the study, scientists from The Scripps Research Institute (TSRI) discovered the activation of a single protein known as CRTC2 and its effects. (Agencies)
"The sympathetic nervous system gets turned on during intense exercise but many had believed it wasn't specific enough to drive specific adaptations in exercised muscle," said Michael Conkright who led the study.
The findings show that not only does it target those specific muscles but it improves them - the long-term benefits correlate with the intensity of the workout, Conkright noted.
Following high-intensity exercise, CRTC2 integrates signals from two different pathways - the adrenaline pathway and the calcium pathway. This directs muscle adaptation and growth only in the contracting muscle. Using mice genetically modified to conditionally express CRTC2, scientists showed that molecular changes occurred that emulated exercised muscles in the absence of exercise.
In the genetically altered animal models, this resulted in a muscle size increase of approximately 15 percent."If you think of the adrenaline system as something that mobilizes resources when you encounter, say, a bear on your way to work, what we found is that the system also gets you ready for your next bear encounter," Conkright said.
The study was published in The EMBO Journal.
In the study, scientists from The Scripps Research Institute (TSRI) discovered the activation of a single protein known as CRTC2 and its effects.