Does exercise burn more calories during fasting?

Exercise does require the body to burn more calories, and during fasting, you still use the calories stored in your body. Initially, the body burns glycogen, which is the stored form of sugar in the liver. However, because exercise demands more energy, glycogen is depleted faster than usual. Typically, your body has enough glycogen to last about twenty-four hours, so there’s usually enough available to fuel your exercise before it runs out. For example, during high-intensity activities like HIIT (High-Intensity Interval Training) or strength training, your body quickly uses up its glycogen stores, which can lead to muscle fatigue if not properly replenished during eating periods. This is why athletes practicing intermittent fasting may need to adjust their workout intensity or timing to ensure they have enough energy for optimal performance.