From Welma.ai (makes it simpler to understand)
Scientists think that when we exercise, our muscles release tiny particles called extracellular vesicles (EVs) that can travel through our body and do good things. In this study, researchers found that when mice did a certain type of exercise that made their muscles bigger (called mechanical overload), their muscles released EVs that contained a special molecule called miR-1. These EVs traveled to fat cells in their body and gave them a signal to start burning fat. This happened because miR-1 turned off a gene that normally stops fat cells from burning fat. When the researchers stopped the muscle cells from releasing EVs, the fat cells didn't burn as much fat. They also found that when people did resistance exercise, their muscles released miR-1 in a similar way. This means that when we exercise, our muscles can talk to our fat cells and help them stay healthy.