Sumary of Lifting weights? Your fat cells would like to have a word:
- Once considered microscopic trash bags stuffed with cellular debris, vesicles now are known to contain active, healthy genetic material and other substances.
- Intriguingly, some experiments indicate that aerobic exercise prompts muscles to release such vesicles, conveying a variety of messages.
- But few studies had looked into whether resistance exercise might also result in vesicle formation and intertissue chatter.
- They first experimentally incapacitated several of the leg muscles in healthy adult mice, leaving a single muscle to carry all the physical demands of movement.
- Before and after that process, the researchers drew blood, biopsied tissues, centrifuged fluids and microscopically searched for vesicles and other molecular changes in the tissues.
- Before their improvised weight training, the rodents’ leg muscles had teemed with a particular snippet of genetic material, known as miR-1, that modulates muscle growth.
- In normal, untrained muscles, miR-1, one of a group of tiny strands of genetic material known as microRNA, keeps a brake on muscle building.
- After the rodents’ resistance exercise, which consisted of walking around, though, the animals’ leg muscles appeared depleted of miR-1. At the same time, the vesicles in their bloodstream now thronged with the stuff, as did nearby fat tissue.