Cardio also elevates the body’s metabolic rate, even after the workout is done. This provides a longer-lasting energy boost. So cardio in the morning not only burns a higher proportion of fat, but it also increases energy levels for the rest of the day. Still, people should take care not to do more than 40 minutes of cardio on an empty stomach, just to ensure they don’t lose muscle.
Research Supporting Morning Cardio
A study from the journal, Medicine and Science in Sports and Exercise, found that after a 12-hour fast, the amount of fat burned from aerobic exercise was 17% higher than when the same exercise was done after eating or later in the day. Another study from The Journal of Applied Physiology concluded, “Our results support the hypothesis that endurance training enhances lipid oxidation in men after a 12-h overnight fast at low relative exercise intensities”.
Another study that looked specifically at maximizing fat loss concluded, “The ability of exercise to selectively promote fat oxidation should be optimized if exercise is done post-absorptively (preferably during morning fasting metabolism)”……….