Some exercisers bound out of bed at 5.30am and arrive at work knowing their daily exercise is taken care of. Others sneak out at lunchtime for a quick run around the park or Pump class to recharge their batteries for the afternoon. And others swear by the stress-relieving benefits of a solid weights session when the working day is done.
Most of us organise our exercise around our schedules and commitments. But is there a specific time of day that allows us to train the most effectively? The Biggest Loser Club takes a look at the pros and cons of exercising at different times of the day, so you can decide what’s best for you.
Reasons to exercise in the morning
Early exercisers are more likely to stick with a fitness regimen than those who leave it until later in the day as unforeseen circumstances are less likely to arise.
Furthermore, Associate Professor Steve Boutcher, Director of the Fat Loss Laboratory at the University of NSW, believes that, if you want to lose fat, the best time to exercise is before breakfast.
He says, “First thing in the morning, the body has effectively run out of carbohydrates or sugars for fuel and switches to burning fats instead. One way that it does this is by releasing an enzyme that stimulates the fat cells to release their fats.”
What if you can’t exercise on an empty stomach?
Professor Boutcher advises, “If you can’t face working out before breakfast or you’re really hungry, have a small snack. Low GI carbs enhance fat burning, while processed high GI carbs prevent it.”
That means a small serve of yoghurt or 10 almonds is a better option than a slice of white toast.
Early risers claim that morning exercise enhances their mood. Being up and active early can boost physical energy and mental alertness for the day ahead.
The participants in a study published in the journal Appetite reported feeling in a better mood from taking an aerobics at 8.15am than 7.15pm. The study’s leader, Dr Siobhan Higgins, said that the early morning workouts provided a 48% morale boost compared with 19% for later in the day.
On the flip side, body temperature is at its lowest after waking, so you naturally have less energy and exercise feels harder. It’s extra important to warm up well to prevent injury.
Reasons to exercise at lunchtime
If you can put the time aside regularly, lunchtime exercise is a productive option. Your reaction time is quicker, lung capacity is improved and exercise feels like less effort. Your muscles and joints are warmed up and flexible, reducing the risk of injury. Your higher body temperature at this time lowers your resting heart rate and blood pressure. This increases your energy and strength, so you can push harder.
There is also a mental benefit. Exercising in the middle of the day increases blood flow to the brain, so you’re sharper for your afternoon duties.
On the downside, time constraints might mean your workout has to be short.
Reasons to exercise in the evening
In the afternoon and evening you are in a different biological state from the morning. It is the time of greatest biological efficiency for most people. The best performances of many athletes, including world records, are typically in the late afternoon or early evening.
“Exercising in the evening is a good way to gain strength, and that’s why strength trainers like power-lifters train in the evenings,” says Professor Boutcher.
“The muscles have warmed up by the afternoon or evening and certain hormones that are necessary for muscle-resistance work are optimal at this time.”
Evening exercise can also help to regulate the amount you eat for dinner, which is beneficial if you tend to eat big meals at night. It’s also a great stress reliever after a busy day.
On the downside, vigorous activity before bedtime can interfere with sleep by raising body temperature and increasing hormone activity. Finish your session at least 1 to 3 hours before bed.
Circadian rhythms and exercise
Your circadian rhythm is your body’s unique biological pattern during a 24-hour period. It governs:
- temperature
- metabolism
- hunger
- blood pressure
- energy levels
Since everyone has a different sleep, work and activity pattern, everyone’s circadian rhythm is different.
Body temperatures progressively rise and lower throughout the day, and your circadian rhythm dictates when your body temperature is at its peak. Exercise is more effective at this point, and your energy levels are highest.
However, your body’s preferred time for exercise may coincide with an urgent meeting or when you’re picking up the kids from daycare. The most important thing is not so much the time of day when you exercise, but that you do so regularly and consistently.
That means whenever you can fit a workout into your day is ultimately the best time for you.