Best Time of Day to Exercise for Weight Loss: What the Science Says

Article posted in: Fitness Experts’ Corner
woman getting ready for morning workout

Is there a best time of day to exercise for weight loss? Some research says yes. Morning, afternoon and evening workouts can affect fat burning, appetite control and energy levels in different ways.

But like everything in weight loss, consistency matters most. Any movement you can fit into your day is a win. The important thing is choosing a time that fits with your schedule, energy levels and lifestyle so you can stick with it. 

That said, if you want to maximize your efforts, it helps to understand how exercise timing may impact results. Here is what the science says to help you decide what works best for you. 

How Could Exercise Timing Impact Weight Loss?

When thinking about weight loss in terms of calories in versus calories out, the timing of exercise seems like it shouldn’t matter. However, scientists are finding connections between circadian rhythms and how our bodies respond to exercise at different times of the day.

Your circadian rhythm is basically your body’s internal clock. It influences everything from hormones to metabolism and physical performance.

For example, insulin sensitivity is higher in the morning, which could help control blood sugar. In the evening, body temperature peaks, meaning strength, endurance and fat metabolism may be at their best.

Exercise timing might also affect appetite and sleep, two major factors in weight management. Some people naturally eat less throughout the day after a morning workout, while others find that evening exercise helps them de-stress and sleep better.

While there is still more to learn, one thing is clear: consistency is the biggest factor in success. But if you have flexibility, changing when you work out might help you reach your goals faster.

Here is what to consider when exercising at different times of the day.

The Pros and Cons of Exercising in the Morning for Weight Loss

Getting your workout in early means one less thing to worry about as the day gets busy. It also might make it easier to keep your weight in check.  

A recent study in The Obesity Society journal found that people who exercise in the morning have a lower risk of obesity than those who work out later. Researchers analyzed data from over 5,000 participants in the CDC’s National Health and Nutrition Examination Survey and saw a clear trend toward better weight management in morning exercisers. 

Since this was an observational study, it does not prove cause and effect. However, other research suggests morning workouts may help with fat-burning and consistency. 

What the Research Says 

  • A study in Frontiers in Physiology found that women exercising in the morning lost more abdominal fat than those exercising in the evening. Men, however, burned more fat with evening workouts.
  • A study review found that people who exercised in the morning were more consistent and worked out more often.  
  • Some research suggests that morning workouts help control appetite, which could result in eating less calories throughout the day.  

Pros 

  • More likely to become a habit
  • May help women burn more fat
  • Can curb appetite throughout the day
  • Less likely to be interrupted by daily obligations

Cons 

  • Performance might be lower due to body temperature and energy levels 
  • Waking up early can be tough and interfere with healthy sleep patterns 

The Pros and Cons of Exercising in the Afternoon for Weight Loss  

If mornings aren’t possible, midday workouts might be a better fit. Beyond convenience, some research suggests afternoon exercise is best for heart health. 

Another perk is that an afternoon workout can help fight the midday slump that often leads to snacking or reaching for sugary energy drinks. 

What the Research Says 

  • A large study in Nature Communications found that people who exercised between 11 a.m. and 5 p.m., especially older men, had lower heart health risks than those who exercised in the morning.
  • Exercise, particularly aerobic workouts, helps lower the hunger hormone ghrelin while raising appetite-suppressing hormones like GLP-1, which may make it easier to manage afternoon cravings.

Pros 

  • Doesn’t interfere with sleep schedule
  • May benefit heart health
  • Can help combat the afternoon slump and cravings 

Cons 

  • Harder to fit into a busy schedule
  • Energy dips after lunch may reduce motivation

The Pros and Cons of Exercising in the Evening for Weight Loss  

For some, late-day workouts are the easiest to fit in. You are done with work, your schedule is more flexible and you might have more energy. 

Another benefit is that body temperature peaks in the late afternoon and early evening. This peak can support better strength and performance during workouts. If building strength is your goal, evening workouts may be the best choice. 

What the Research Says 

  • A research review suggests muscle strength and flexibility are best later in the day compared to the morning. 
  • Some research suggests that late workouts may interfere with sleep, but it is unclear if that affects weight.  

Pros

  • Muscle strength and flexibility may be at their highest point
  • May help relieve stress after a long day
  • Offers more flexibility in scheduling

Cons

  • Higher risk of skipping due to fatigue or social plans
  • Can possibly interfere with sleep if done too late

How to Choose the Best Exercise Time for You 

Each time of day has its benefits, but the biggest factor in weight loss is sticking to a routine that fits your life.

That is why I often recommend morning workouts. They are linked to better consistency, and consistency leads to results. But that does not mean morning is the best choice for everyone. 

To find what works best for your schedule, energy levels and lifestyle, ask yourself:  

  • What is my main goal? Fat loss, strength gains or heart health? 
  • When do I feel the most energized?
  • What time of day am I most likely to stick to a routine?
  • Do I need to fit my workout around work, family or other responsibilities?
  • Do I perform better in the morning, afternoon or evening?

If you’re still not sure, just pick a time and experiment. Getting started is what counts. Try morning workouts and pay attention to how you feel and your consistency. Assess at the end of the week and switch it up if you need to.  

Tips for Sticking to Your Exercise Routine 

Once you have an idea of which direction to go, make a plan:  

  • Schedule it like an important meeting.
  • Prepare ahead by setting out workout clothes or packing a gym bag.
  • Choose activities you enjoy so it doesn’t feel like a chore.
  • Find a backup plan in case your preferred time doesn’t work out.
  • Track progress to stay motivated.

Remember, regular exercise benefits more than just weight loss. Every time you show up and put in the effort, you build a healthier, stronger version of yourself. Commit to the process, and you might surprise yourself with what you can achieve. 

References 

  1. Blankenship JM, Rosenberg RC, Rynders CA, Melanson EL, Catenacci VA, Creasy SA. Examining the Role of Exercise Timing in Weight Management: A Review. International Journal of Sports Medicine. 2021;42(11):967-978. doi:https://doi.org/10.1055/a-1485-1293 
  2. Ma T, Bennett T, Lee CD, Mairead Wicklow. The diurnal pattern of moderate‐to‐vigorous physical activity and obesity: a cross‐sectional analysis. Obesity. Published online September 4, 2023. doi:https://doi.org/10.1002/oby.23851 
  3. Arciero PJ, Ives SJ, Mohr AE, et al. Morning Exercise Reduces Abdominal Fat and Blood Pressure in Women; Evening Exercise Increases Muscular Performance in Women and Lowers Blood Pressure in Men. Frontiers in Physiology. 2022;13. doi:https://doi.org/10.3389/fphys.2022.893783 
  4. Schumacher LM, Thomas JG, Raynor HA, Rhodes RE, Bond DS. Consistent Morning Exercise May Be Beneficial for Individuals With Obesity. Exercise and Sport Sciences Reviews. 2020;48(4):201-208. doi:https://doi.org/10.1249/JES.0000000000000226 
  5. Fillon A, Mathieu ME, Boirie Y, Thivel D. Appetite control and exercise: Does the timing of exercise play a role? Physiology & Behavior. 2020;218:112733. doi:https://doi.org/10.1016/j.physbeh.2019.112733 
  6. Feng H, Yang L, Liang YY, et al. Associations of timing of physical activity with all-cause and cause-specific mortality in a prospective cohort study. Nature Communications. 2023;14(1). doi:https://doi.org/10.1038/s41467-023-36546-5 
  7. Thackray AE, Stensel DJ. The impact of acute exercise on appetite control: Current insights and future perspectives. Appetite. Published online April 2023:106557. doi:https://doi.org/10.1016/j.appet.2023.106557 
  8. Mirizio GG, Nunes RSM, Vargas DA, Foster C, Vieira E. Time-of-Day Effects on Short-Duration Maximal Exercise Performance. Scientific Reports. 2020;10(1). doi:https://doi.org/10.1038/s41598-020-66342-w 
  9. Douglas CM, Hesketh SJ, Esser KA. Time of Day and Muscle Strength: A Circadian Output? Physiology. 2021;36(1):44-51. doi:https://doi.org/10.1152/physiol.00030.2020 
  10. Perrier J, Langeard A, Chandrou Koumar Ouma, et al. Effects of acute bouts of evening resistance or endurance exercises on sleep EEG and salivary cortisol. Frontiers in physiology. 2024;15. doi:https://doi.org/10.3389/fphys.2024.1313545