It’s commonly thought that working out on an empty stomach can lead to more fat loss due to fat being used as fuel for exercise. The theory is that the overnight fast causes lower stored glucose levels which makes your body shift energy away from carbs in favor of fat. This is not fully supported by science. There is conflicting evidence supporting both sides of the argument.
Mid your working out in a faster state, energy levels should be taken into account. Without food for any length of time , this effects low blood sugar levels and is detrimental to performance and it’s unlikelythat your exercise output would be at optimum levels had you have eaten a meal prior to training, this has been shown through research. Another study shown the perception of eating food prior to exercise with a placebo resulted in better performance compared to water alone. If your in a situation where food isn’t plentiful, this shouldn’t persuade you from not exercising. A fasted workout is better than not working out at all. It is a small difference in outcome.