Print Edition: February 4, 2015
Interestingly, the time of day you work out makes a difference in how your body breaks down fat. Why do you work out? For some it’s about muscle gain, for others it’s about performance, and even more still just want to get a good night’s sleep. Everyone knows you need to be active to keep happy and healthy. But for most people, it’s all about weight loss.
People prefer different hours to exercise. There are early birds and late worms (you know the old saying — “the late worm stays alive”) and I’m definitely a late worm. But if I want to work out for weight loss, I might have to change my ways.
Weight loss is affected by your body’s rhythms and cycles. You can synchronize your workouts with optimal times in this cycle.
A Danish study shows that working out before breakfast might do the trick. The study, published in the Journal of Physiology, took three groups of young men, feeding them all high-fat diets. The first group worked out before breakfast, the second after breakfast, and the third group not at all (poor third group).
At the end of six weeks, those who worked out before breakfast hadn’t gained weight and had healthy insulin levels. Insulin is key to weight loss. Those who worked out after breakfast gained about three pounds, and had offset insulin levels. And no one ever saw the third group ever again. Just kidding! We just don’t talk about them anymore.
This study would suggest that working out prior to breakfast will give you more bang for your buck. However, the flaw here is that the study doesn’t have anyone working out later in the day, so we can’t compare.
Yet there is evidence that working out later on has its benefits. Let’s talk cortisol. Cortisol is a stress hormone. It does good things, according to the US National Library of Medicine’s website MedlinePlus — it maintains your blood pressure, metabolises fats, helps out with the nervous system, and gives you a kick for your fight-or-flight reaction. But unless there’s a bear on campus, you don’t want high levels of cortisol. That’s because it’s trying to save you by storing fat. Cortisol is worried. Are you okay? Cortisol will make sure you’re all good. Therefore weight loss isn’t easy with high levels of cortisol. You can’t help stress levels sometimes. However, cortisol tends to stay at higher levels in the morning.
Wellness website Fitbie notes that cortisol is highest at about 8 a.m., and lowest in the evening. If levels are high, working out will raise them higher and higher, until your body is in stress-mode for the rest of the day. It may be best to wait until levels are low, so that your friendly neighbourhood cortisol won’t go breaking down muscles, and hanging on to fat.
In the end, the best way to achieve all of the above is simply this: consistency. The American Heart Association notes that the benefits of physical activity are closely linked to how often you work out. If you’re a late worm and you’re forcing yourself to get up early, how long are you going to keep that up? Chances are, if you work out during the time of day you feel good, you’ll stick to your schedule.