The Best Time to Run to Reduce Belly Fat, According to a Fitness Instructor

You might be an avid runner who's training for an upcoming marathon or someone who likes a gentle few kilometers once a week. Either way, there's no doubt that running is great for losing weight and keeping fit.

But what if the time of your run changed how impactful it could be? According to sports nutritionist, Alicia Jones, going for a run in the morning "is the best time to work out."

Although donning sneakers and going for a run first thing in the morning might not be everyone's preference, Jones told Newsweek that "you want to play into your natural cortisol rhythm by working out first thing in the morning, when your energy and cortisol are high."

Cortisol is a hormone that's released by the adrenal glands which can regulate the body's response to stress, regulates blood pressure and blood sugar, and plays a role in the body's sleep cycle. Typically, a person should have a higher cortisol level in the morning when they wake, and a lower cortisol level in the evening.

The Cleveland Clinic suggests that morning levels of cortisol can vary from 10 to 20 micrograms per deciliter, whereas afternoon and evening levels are between three and 10 micrograms per deciliter. It should normally peak in the morning and gradually decrease as the day progresses.

As a nutritionist and certified fitness instructor, Jones has helped many clients, particularly women over 50, lose weight and keep it off.

She explained how early morning running is so vital: "When cortisol is high, you've got the most energy to work out with. But if you start working out later in the evening, then what happens is that your cortisol levels, which should be lower, rise.

"This in turn stores belly fat because your body has a flight response. When the body goes into flight response it needs energy quickly, so it holds onto fat in the belly," she said.

A study from the journal Frontiers in Physiology conducted in 2022, which looked at the variation between morning and evening workouts, found potentially pivotal differences for men and women. The 12-week study concluded that exercising in the morning helped reduce abdominal fat and blood pressure for the women involved, and working out in the evening increased their muscle strength.

The male participants showed similar results, but those who worked out in the evening had significantly decreased blood pressure and fatigue.

You might also think that not eating anything before a run is the way to go, but that isn't necessarily the case. Jones highlights the importance of fueling your body properly and providing it with the energy it needs to work out.

"Make sure that you're working out in the morning, especially if it's cardio-based, and that you're eating before you do your workout to ensure that you have the energy to reach your maximum level," she said.

"The old belief was that you're supposed to be in a fasted state to work out so that you tap into your fat stores and burn more fat off. But it really doesn't work that way and it's definitely better to eat than to work out in a fasted state."

Jones encourages fitness enthusiasts to get plenty of carbohydrates before working out as they provide "quick, efficient energy."

For some people, working out in the morning simply isn't an option, however. Not everyone follows the same routines, and certain lifestyles might entail fitting in a workout at dusk rather than dawn. Though she firmly believes that running in the morning is better for losing weight, that doesn't mean depriving oneself of sleep.

As research has shown that moderate or intense exercise increases the circulation of cortisol in the body, Jones discourages people from running late in the evening and suggests they choose another exercise.

"Sleep is more valuable than getting in a workout, especially for belly fat loss," Jones told Newsweek. "You want to make sure that you have adequate sleep, and if that means that you have to work out in the evening then you should make sure that your workout consists of weight training rather than long bouts of cardio.

"By elevating your cortisol at night, you're storing more fat and increasing your energy, making it harder to sleep at night. If you have to work out at night, stick to weight training and keep your cardio to the morning to keep your cortisol levels natural."

Despite Jones' firm stance on the importance of a morning run, not everyone is quite so adamant. Rachel MacPherson, a certified exercise nutritionist and a health and fitness author, suggests that the best time of day to work out is simply what fits the individual's schedule.

She suggested that it's "primarily a personal decision" for each individual, and the time of day will have little reward.

"The best time of day to work out is a time that fits into your schedule, in a way that works with your lifestyle, previous commitments, and motivation or energy levels," MacPherson told Newsweek. "My best advice is to choose the time of day that suits your lifestyle. One thing to consider is whether your day drains you, and how likely things will get in the way in the evenings. If you work out in the morning, then it's over and nothing can get in the way of getting it done."

So, whether you're filled with excitement for the route you're about to take, or there's an overpowering sense of dread as you put on your sneakers in the morning, being consistent with the schedule is fundamental to seeing results.