Great question from one of our personal training clients in Taringa this last week:
Should I do my workouts in the morning or the evening for better weight loss?
When it comes to working out, most of us want to maximize the results we get, so it would make sense to work out when your body can make the most of it. Popular belief in the personal training and body building worlds holds that cardio first thing in the morning is a great fat burner, perfect for losing weight and toning up. How true is that?
The answer: Somewhat.
There is evidence that morning exercise can set you up for better fat burning (and improvements in other health markers) throughout the day, meaning that over the course of the day, you may burn slightly more fat than you might if you were relying solely on evening exercise. Why am I talking about fat burning if you want to lose weight? Body fat loss is far more likely to be what achieves your weight loss goal, than overall weight loss. Body composition is what determines how lean and toned you look, and from a health perspective, lower body fat levels are associated with lower levels of health risk; fat loss rather than weight loss can significantly improve your health.
Any exercise you do will have a positive impact on your body fat levels, regardless of what time of day you do it. But both morning and evening workouts have their own benefits. Several factors are in play here:
- Exercising leads to a slight to moderate increase in metabolism during the “recovery period”, or the time after your workout when your body is busy replenishing cellular energy stores and making repairs to tissues. Because of this, exercise in the morning may provide a slight advantage by adding to the normal amounts of energy used during your daily activities. Overall, you may see a small increase in overall energy (calories) burned during the day. It’s important to note that this difference will be minor, especially if your morning workout is low to moderate intensity, and will not be enough to make a huge difference to body weight and body composition in a short or even moderate/medium time frame – this is for playing the long game.
- Some studies have shown an increase in fat burning tendencies after exercise in the morning compared to exercise in the evening, though other studies have found no differences. This also appears to be dependent on the types of fats in your diet, with unsaturated varieties being more easily used than saturated fats. This can be particularly useful if you’re exercising for heart, cardiovascular, or metabolic health.
- Exercise intensity and the resulting hormonal and immune responses (generally thought to be related to the physical stress of exercise) both influence the use of fats versus carbohydrates in providing energy at a cellular level. In normal physical function, these responses are influenced by the time of day as well as how you exercise. Many physical responses to exercise are amplified in the evening; Evening exercise appears to increase the body’s hormonal and immune responses, which in turn can lead to higher release of fat molecules into the bloodstream – basically, leading to increased breakdown of fat stores. It’s important to note, however, that increased breakdown of fat stores does not necessarily mean increase fat burning, as these molecules may continue to circulate in the blood without being used.
- Given that the hormonal responses to exercise are heightened during the evening hours, you may wish to consider how these might impact your sleep. One normal exercise response is to increase levels of your “fight or flight” hormones, making you more alert – rather than ready for bed. If you already have sleep challenges, you may wish to avoid evening exercise.
- Exercise at any time of the day is can be followed by a decrease in blood pressure. While this response is larger after evening exercise, there is evidence that the blood pressure decrease after morning exercise is more consistent. It may also be more valuable if you are prehypertensive or have high blood pressure. As part of normal body functions, you experience a temporary rise in blood pressure in the mornings; the decrease in blood pressure following morning exercise can return these morning “spikes” to more normal levels.
Evidence exists for both morning exercise and evening exercise to be more effective in fat burning and weight loss, and there are mindset and motivation effects of morning exercise that are hard to look past. For example, if you hit the gym in the morning, will that make you less likely to grab that pastry from the office kitchen for breakfast? Regardless of the science and the mindset effects, your work outs, your ability to lose weight, and your health will all stand to make the most improvements on your own timeline. The most effective workout time is going to be the time when you feel best prepared for it.
For more information:
De Bristo, L. C., Rezende, R. A., Da Silva, N. D., Junior, Tinucci, T., Casarini, D. E., Cipolla-Neto, J., & Forjaz, C. L. (2015). Post-Exercise Hypotension and Its Mechanisms Differ after Morning and Evening Exercise: A Randomized Crossover Study. Plos One,10(7).
Kim, H., Ando, K., Tabata, H., Konishi, M., Takahashi, M., Nishimaki, M., . . . Sakamoto, S. (2016). Effects of Different Intensities of Endurance Exercise in Morning and Evening on the Lipid Metabolism Response. Journal of Sports Science and Medicine,15, 467-476.
Kim, H., Konishi, M., Takahashi, M., Tabata, H., Endo, N., Numao, S., . . . Sakamoto, S. (2015). Effects of Acute Endurance Exercise Performed in the Morning and Evening on Inflammatory Cytokine and Metabolic Hormone Responses. Plos One,10(9).
Votruba, S. B., Atkinson, R. L., & Schoeller, D. A. (2004). Sustained increase in dietary oleic acid oxidation following morning exercise. International Journal of Obesity,29(1), 100-107.