Whether or not you consider yourself a “creature of habit,” it’s inevitable that life is a series of routines. You wake up every morning, you go to sleep every night. And, sometimes, you workout. The question of when to fit a workout into your routine has been the focus of many studies and experiments over the years. Most experts agree that working out in general is more important than working out at a specific time. However, some studies have pointed to “peak times” for exercise for the best physiological benefits. It’s like this: You can enjoy watching The Bachelorette at any time, but watching during prime time has its bonuses (think: watching Twitter blow up). Similarly, you can reap small benefits from working out at the right time.
But physiologically, Dr. Anthony Hackney, professor of exercise physiology & nutrition at the University of North Carolina, Chapel Hill, says how you work out is more crucial than when. He says high intensity workouts tend to result in a greater energy expenditure, making them one of the best bangs for your buck in terms of working out.
But timing can affect how hard you go during HIIT, and how motivated you are to push your body to work harder. “We’re all different individuals with different chronotypes, which you might better understand as: Some people are morning people and some are evening people... it’s like chronology.” So, if you’re a morning person, you might wake up alert and ready to jump into something. “Being alert is something that affects motivation,” says Hackney. “Chronotypes affect people’s desire to exercise and how well they’re going to workout. You’ll be more motivated if you’re alert.” So, if you’re a morning person, you’re more likely to push yourself harder at that time, but if you're not a morning person, you might be better off working in the afternoon or evening.
With that said, there are still some physiological and mental benefits you can reap from doing your workout at specific times. These are the best "peak" times to exercise to achieve your individual goals.
Best time for weight management: morning workouts
There are some physiological perks to morning workouts in general. Working out first thing on an empty stomach may be more conducive to burning stored fat, because of your body’s hormonal composition, Hackney explains.
“If you wake up in the morning and decide you want to go exercise before eating, you’re really relying on energy reserves you have stored to do that exercise,’ Hackney says. “Most of us have far more of our energy reserved as fat than we do in other sources.”
But Hackney says there's a caveat. If not eating before working out leaves you feeling sluggish, you should listen to your body because it could make you less likely to workout intensely. If that’s the case, eat a lite snack such as a piece of toast or banana before you take on the workout.
These perks might sound great if you’re a morning person, but if you’re one of those people who has to use the jaws of life to force yourself out of bed, it could sound discouraging. Health strategist and fitness professional Jay Cardiello says you shouldn’t let this get you down. “Any time a person implements exercise or movement based activities, it’s a good thing,” Cardiello explains. “Unless you’re an athlete, it doesn’t matter when you workout — it’s about consistency.”
Cardiello says working out in the morning can help put you in a good mental state for the rest of the day, though. “It can give you a separation in the morning between rest and work, and help you gain better control of day,” Cardiello says. “The first eight or 11 or 20 minutes of your day dictate success — whether you’ll be victor or victim. If you wake up and journal or do yoga or exercise, the time you take sets tone for rest of day. You’ve already accomplished something and made your health a priority.”
But there’s no pressure to force yourself to the gym if morning workouts aren’t your thing, Cardiello says, because there are also benefits to afternoon and evening workouts.
Best time for intense training: afternoon workouts
Hackney says afternoon workouts can also be beneficial. The perk of these workouts is that by the afternoon, you’ve had time to get a few good meals in, which can raise your blood sugar levels, making it easier to do more high intensity things. A Journal of Physiology study noted that working out between 1 p.m. and 4 p.m., like a morning workout, can shift forward your body clock and help you recover from things like jet lag more easily.
Cardiello says afternoon workouts can also help if you’re in a lull before a meeting or something you ate for lunch is dragging you down. “It can help you get back in gear and be more present later on in the day,” he says.
Best for stress management: evening workouts
There’s some conflicting research out there about evening workouts, and how they impact your sleep. The Journal of Physiology found working out between 7 p.m. and 10 p.m. may delay the body clock, making you go to sleep later. But a paper published in the journal Experimental Physiology found nighttime exercise wasn’t disruptive to sleep, and could even reduce levels of the hormone ghrelin, which stimulates hunger. Hackney says the recovery period after exercising could suppress appetite and make you less likely to crave evening snacks.
"[Working out in the evening] is a good buffer time to process the stress of your work day, leaving you more fully present when you got home to your friends or family," Cardiello says. “Having 20 minutes or an hour of exercise [in the evening] will help decrease cortisol levels, relieving stress, so you have a good separation between your professional and personal life.”
Best time in the month: workout on your period
Hackney did research looking at how working out at different points in your menstrual cycle may impact the way you exercise. The research found that, in some cases, the second half of your menstrual cycle after ovulation may cause you to metabolize more fat as an energy source, compared with the early part of the cycle. He says this is because estrogen tends to spikes after you ovulate. "So, when you go to the gym during this time you may actually be burning more fat," Hackney explains.
Best time overall: when it works for you
Ultimately, the best time to workout isn’t about small physiological gains. It’s about carving out time for yourself, and accommodating your schedule and chronotype. If your work and life schedule doesn’t align with your chronotype, you can train your body to workout at a new time, Hackney says. Say you’re really a night owl, but you don’t have time to workout at night because that’s when your kids need help with homework. You can train yourself to be a morning exerciser by easing into it.
“If you’re interested in changing your pattern, don’t drastically switch your routine automatically,” Hackney says. Maybe you workout for an hour in evening, and want to change it up. “Don’t automatically start doing an hour in the morning,” Hackney says. “Let your body have transition time to see what it’s like to get up and do exercise.” Try 15 minutes, and then work your way up to more time. Don’t put too much pressure on yourself.
As, Cardiello says: “It’s all about consistency.”