BCAAs are directly metabolised in the muscles, hence they are extremely useful for athletes. BCCAs maintain the glycogen reserves to prevent your body from breaking down the muscle proteins for energy, which in turn halts muscle breakdown. Consuming BCAAs directly instead of through protein supplements or other foods leads to faster absorption and utilization by the muscles. During workouts, BCAAs prevent the serotonin levels from increasing in the brain for signaling the body to start winding down. This helps delay muscle fatigue.