Highly Branched Cyclic Dextrin(HBCD) is a fast emptying starch (faster than glucose) that moves quickly through the gut and into the muscles providing the carbohydrate required by the body during high intensity training of competition. We recommend using products containing HBCD after the first 30 minutes of intense (HIIT, intervals, tempo etc) exercise or racing.  This approach supports the most rapid triggering of insulin INDEPENDENT glucose transporters in the muscle cells to absorb and utilize glucose while also supporting the simultaneous use of fat for fuel.