Whether you're fit or out of shape, male or female, young or older, working out before breakfast still burns more fat than after eating — as long as you're not sprinting at max effort.

Working out before eating breakfast burns about 3 grams more fat than working out after eating, because your body has to use stored fat for energy when you haven’t eaten.

Doing a tough weight workout before jogging or cycling helps your body burn more fat while you're doing the cardio.

When endurance athletes do high-intensity interval training at very hard effort (over 85% of their maximum oxygen capacity), they burn fat at extremely high rates - about 1.58 grams per minute on average, with some burning over 1.85 grams per minute. These are the highest fat-burning rates ever measured in people.

Working out on an empty stomach in the evening makes your body burn more fat and less sugar during the workout.

When you work out in the evening without eating beforehand, your body burns more fat and less sugar for energy during the workout.