It’s 5:00am and your alarm blares, beckoning you out of bed for your morning run. As you sip a glass of orange juice with eyes barely open, you wonder if running in the evening might be a better option. Or maybe it’s 6:00pm and you are just getting off work, and the thought of going home, changing into workout gear, and heading back out for a run is the last thing your exhausted body wants to do, and you wonder if you would do better running in the morning instead. So, which is better – morning or evening running?
The morning vs. evening running debate is far from new and there are people who strongly advocate for each. Which is better depends on many factors:
The first thing to consider is why you are running. If you run at low- to moderate-intensity to improve general health, lose weight, or train for longer-distance races where it is important to be consistent, then a morning running schedule may be better suited to you. Many people feel it is easier to adhere to an exercise regimen when they schedule it first thing in the morning. In contrast, evening workouts may be easier to neglect and make excuses for, especially after a long, tiring day. But regardless of which is easier to keep up, consistency is key if your goal is weight loss or improved cardiovascular fitness. Choose the time of day that you’re more likely to stick with.
On the flip side, if you are running for time/speed or training to improve sprint, agility, or other high-intensity work, an evening workout schedule may be more beneficial. Several studies have shown that muscle power, reaction time, and aerobic capacity are somewhat higher in evening compared to morning (1). This may be due to a difference in metabolic energy systems being used, higher core body temperature, and how you’re fueled. If athletic performance is what you’re training for, you might find better outcomes in the evening.
Fuel (a.k.a. Nutrition)
Speaking of fuelling, evening running has an advantage over morning because you’ve had much of the day to hydrate and eat at least two meals and perhaps a couple of snacks. Your body has better carbohydrate stores needed to immediately fuel a workout. In the morning, however, your body has fasted overnight, and even if you eat or drink something light before your morning run (which you should do!), it may not be enough to fuel your entire workout depending on how long you go for. Once you’ve used most of your carbohydrate stores, your body can switch to a greater proportion of fat, but metabolising fat for energy is slower than carbohydrate, and as a result, you would likely fatigue sooner and/or be forced to run slower (2).
Anecdotally, some people report feeling better running in the morning on an empty stomach. If you’re not used to it, eating or drinking shortly before a run may cause abdominal discomfort during the workout. Some also believe running on empty “kick starts” the metabolism to burn more fat the rest of the day, which they believe will aid weight loss. However, because using stored fat for energy is comparatively slower, you may not be running your best if you’ve used up most of your carbohydrate stores. You will actually burn fewer calories during your run, and you will likely reach the point of fatigue much faster than if you ate or drank something small and easily digested beforehand.
Studies also suggest that EPOC, post-exercise oxygen consumption, (i.e. the higher metabolism following exercise compared to rest) is significantly less if you run in a fasted state vs. a fuelled state (3, 4). In other words, the metabolic boost you get after your run is lower and burns fewer calories if you run on an empty stomach than if you eat/drink something before you run.
You can train your stomach to handle a small, easily digestible snack or carbohydrate-based beverage before a run, but it takes time and consistency for your body to adjust. You may have to wake up a little earlier to eat or drink something light (with at least 15-30 grams of easily digested carbohydrates) and allow time for digestion before your morning run, but the metabolic benefits of doing so are far greater than trying to go for a run on an empty stomach.
For some, morning runs are preferred as they can “amp you up” for the rest of the day, and they feel more awake after a morning run. It might even be just as good as a cup of coffee to help them be alert and focus. Then there are those for who running is a welcome stress reliever at the end of a long day running can be a meditative activity, allowing the mind and body to decompress, and an evening run might be just what you need to re-centre and re-focus.
Safety and Injuries
In terms of safety, some experts propose you are less prone to injury in the evening since your body temperature is higher, so the joints and connective tissue are looser than when you’ve recently rolled out of bed. A longer, more thorough warm-up in the morning can help reduce the risk of injury during a morning run. Extended warm-ups can also help improve oxygen delivery since blood vessels tend to be more constricted in the mornings (5).
If you choose evening runs, tripping hazards or falling on uneven surfaces may be greater after sunset. There also tends to be more cars on the road in the evening than in the morning, which may be a concern if your route crosses or goes alongside traffic. Be sure to wear light-coloured reflective clothing and consider carrying a small flashlight.
Sleep, Circadian Rhythms, and Adaptation
Exercising late in the day can affect the sleep cycle, either positively or negatively. Some people find it is harder to get to sleep when they run in the evenings because of the adrenaline and endorphin boost, whereas others don’t notice a difference at all. Some find that an evening run can actually help them go to sleep better than a morning run, whereas others feel that morning runs help them sleep better at night. The response seems to be very individualised, and may require some trial and error to find out how your body responds.
But just as exercise can affect your sleep cycles, the body’s circadian rhythms (which are dictated by the rise and fall of various hormones throughout the day) can also affect how well you run at certain times of the day. An interesting study by Facer-Childs et al. (6) classified test subjects into three different circadian phenotypes: early (early risers), intermediate, and late (night owls). They found that the early risers performed their best in cardiovascular endurance tests around noon, night owls around 7:30pm, and the intermediate group peaked around 4:00pm. Therefore it may be beneficial to schedule your runs on whether you’re an early riser or a night owl.
For some, morning vs. evening running is not so much a choice but rather what family or work obligations may allow. The good news is that even if you have to run at a less-than-ideal time, your body does an excellent job at adapting to a schedule – as long as you are consistent (7). This is especially important if you run races/marathons or are training for a specific sport. If your races are typically in the morning, you should run in the morning so your body learns to be its most efficient at that time. Similarly, if you run track & field or play in sports that are late afternoon or evening, you may want to schedule your runs around the same time of day to adapt.
Do What Works Best For You
As you can see, there are many factors to consider in deciding whether morning or evening runs are better for you. Everyone is different. Lifestyle, schedule, family, work, climate, neighbourhood conditions, safety, and individual preferences vary person to person. It may take some time to figure out and require some trial and error. But once you have it worked out, you’ll be more likely to stick with your routine and will get the most out of your runs!
1.) Chtourou H, Souissi N. The effect of training at a specific time of day: a review. J Strength Cond Res. 2012 Jul;26(7):1984-2005.
2.) Coyle, E. F., PhD. (n.d.). SSE #59: Fat Metabolism During Exercise: New Concepts. Retrieved October 11, 2016, from http://www.gssiweb.org/Article/sse-59-fat-metabolism-during-exercise-new-concepts
3.) Lee YS, Ha MS, Lee YJ. The effects of various intensities and durations of exercise with and without glucose in milk ingestion on postexercise oxygen consumption. J Sports Med Phys Fitness. 1999 Dec;39(4):341-7.
4.) Paoli A, Marcolin G, Zonin F, Neri M, Sivieri A, Pacelli QF. Exercising fasting or fed to enhance fat loss? Influence of food intake on respiratory ratio and excess postexercise oxygen consumption after a bout of endurance training. Int J Sport Nutr Exerc Metab. 2011 Feb;21(1):48-54.
5.) Panza JA, Epstein SE, Quyyumi AA. Circadian variation in vascular tone and its relation to alpha-sympathetic vasoconstrictor activity. N Engl J Med. 1991 Oct 3;325(14):986-90.
6.) Facer-Childs E, Brandstaetter R. The impact of circadian phenotype and time since awakening on diurnal performance in athletes. Curr Biol. 2015 Feb 16;25(4):518-22.
7.) Chtourou H, Chaouachi A, Driss T, Dogui M, Behm DG, Chamari K, Souissi N. The effect of training at the same time of day and tapering period on the diurnal variation of short exercise performances. J Strength Cond Res. 2012 Mar;26(3):697-708.