IIt's an all-too-familiar scenario: You heat up a bowl of last night's noodles for lunch, eat them, then return to your desk and gradually sink throughout the day to the point where you struggle to keep your eyes open. Or perhaps you lack energy when you wake up; or, after a tense start and strong coffee, you start to fade mid-morning. Or, like me, you find yourself completely lethargic after dinner during the winter months.
How common are these peaks and valleys in our energy levels? “If you have an active day, you'll naturally get tired because we're humans, not machines,” says Dr. Linea Patel, a nutritionist and nutritionist. “Being tired at the end of the day before you go to bed is great. But being tired at your desk is not healthy.” Patel says you should see a doctor about chronic fatigue because it could be a symptom of an illness.
But the afternoon slump is perhaps the most common energy slump. “This can be seen across a wide variety of populations, and it has real-world implications,” says Dr. Thomas Margeauhepatologist at Oxford University Hospital with an interest in circadian rhythms and metabolism. “It could just make you feel like rubbish and affect your productivity, or it could lead to people falling asleep at the wheel and getting into car accidents.”
Margeau explains that there are two processes that cause our energy levels to fluctuate. “One is sleep pressure, the natural fatigue that builds up the longer we stay awake. Another is our circadian rhythm, the body's internal clock that sets us a daily activity schedule that begins to decline in the afternoon.”
“Most people experience a dip in energy around 3 p.m.,” says Margeau. “Sleep pressure rises over several hours, and at the same time the circadian signal naturally drops. When these two things coincide, we experience the classic daytime slump. You see the same pattern even in 'bunker' experiments where people live for days without clocks, daylight, or food cues, which shows that this diurnal slump is naturally built into our biology.”
So how do you survive a recession?
go have coffee
“You can artificially increase your alertness by using caffeine, which is the most accessible and socially acceptable stimulant,” says Margeau. How much caffeine and at what time you should stop so as not to affect your sleep depends on your tolerance, Patel says. “Some people metabolize caffeine much faster than others. And for some, if they consume caffeine, it makes them feel very anxious and have a racing heart.” As a general rule, it is not recommended to consume more than 400 mg of caffeine per day. The caffeine content of the drinks varies greatly, but this is roughly equivalent to two cups of coffee a day, and you should stop around lunchtime. Energy drinks are not recommended, Patel adds, “as they often contain a lot of sugar, stimulants and additives that can increase heart rate, cause energy spikes and crashes, and disrupt sleep.”
Caffeine also affects dopamine levels, which is our “lust for life,” says Dr. Katie Cooper, a psychologist and author of This Book Will Give You Energy, which will be published by Quadrille in April. “If you go back to the days of the caveman, dopamine was what kept you going, to find resources, to live another day. If you bring that idea into the present day, it keeps you energized to work or be productive.”
Plan your lunch carefully
“We know that the decline is significantly worsened by eating a large lunch – then in the afternoon you experience a much worse decline in your ability to concentrate and increased sleepiness,” Margeau says. “The parasympathetic nervous system, which is largely responsible for rest and digestion, is highly activated when you eat a large meal, so it’s not surprising that you feel a little drowsy.”
We may feel tired after lunch because “blood going straight to the stomach for digestion is a priority, leaving less for the brain,” says Patel. The key to solving this problem, she says, is watching what you eat. “Eating pasta for lunch is a recipe for leaving you feeling very sluggish in the afternoon. But if you instead included a small, quarter-plate serving of whole grain carbs, that will be enough to give you the energy you need, but not necessarily make you feel the slump.” The rest of your plate should be a quarter protein – “if you want to be energized in the afternoon, you need to include some protein in your lunch” – and the rest vegetables or fruit. Patel admits this can be tricky if you're grabbing a sandwich on the go, and suggests adding a casserole of carrots and hummus or a hard-boiled egg to get the balance just right. As a dietary supplement, B vitamins can provide an extra boost of energy, she adds.
Some of us are reaching for sugar in the face of an energy crash, but this can be counterproductive: “You risk getting a sugar rush and then a second crash,” says Patel. Your best bet would be to consume some protein and chocolate.
“There are certain foods that naturally increase energy,” says Patel. “Banana contains glucose, which provides energy, which is why it is often used in sports.” But it can also cause surge and crash. Instead, Patel suggests green tea for a “slow, targeted and sustained release of energy” thanks to a combination of the amino acid L-theanine and a low dose of caffeine – so, again, use caution in the afternoon if you're sensitive to the latter.
Visit the water cooler
“Most of the time, I find that people who are in a slump are also dehydrated,” says Patel. 1.5-1.8 liters water per day. “If you're slightly dehydrated, you won't be as effective.” The color of your urine is the best way to check your hydration level: “The clearer the better,” says Patel.
Take a walk
What you do after eating is almost as important as the food itself. Returning to a sitting position at a desk is the exact opposite of what works best: a short walk outside. “Simply walking and using different muscles in your body activates the process of digesting and delivering glucose to your muscles,” says Patel. “Getting some fresh air is also a great way to stay alert.”
Dr. Katharina Lederle, a sleep therapist and chronobiologist (who studies biological rhythms), advises her clients to get up every hour to take a short break from movement to increase alertness: “Prolonged sitting is associated with poor sleep and can negatively affect concentration, while getting up regularly improves energy levels, alertness and sleep.”
But Cooper adds that it's important not to overexert yourself if you're very tired. “If you're tired and then cane yourself in the gym, it may give you a little dopamine hit, but it will also make you pass out. Listen to your body, and if you're too tired, go for a walk instead.”
Chat with colleagues
Interacting with others is a guaranteed way to wake yourself up, says Lederle: 2018 study. the study showed that socializing during a microbreak had a positive impact on productivity. With the rise in popularity of working from home, this isn't always easy to do, but Lederle says texting a friend or even just looking at photos can have a similar effect.
Smartphones can trigger dopamine, but Cooper doesn't recommend fast scrolling to overcome boredom. Instead, we should look for more adaptive activities: “In the days of the caveman, everyone would go outside and explore; it would be an adventure. Variety is the spice of life. Being able to do a little exploration throughout the day, like taking a different route home, will be energizing because it's new and exciting.”
Extreme temperature exposure, such as plunging into ice or going to a sauna, can also perk things up by improving circulation, and the drop in dopamine levels afterwards is slower than if you drank hot chocolate, Cooper says.
Go outside
Another thing to play with is light. “Light is a very powerful stimulator of the circadian system, signaling alertness,” says Margeau. At this time of year, going to work in the dark and returning home in the dark, it's important for workers to get out during the day “and get some daylight, just to signal to the circadian system that it's daytime and they should be awake.”
Sleep well – or take a nap
You can't improve your daytime energy without working on your nighttime sleep. “If you wake up after a bad night's sleep, you're not going to have a good day,” Cooper says. Positive sleep hygiene, according to Margeau, includes: “Getting daylight in the morning, avoiding caffeine in the afternoon, resting 30 to 60 minutes before bed, reducing screen time in bed, and keeping the bedroom cool, dark, and quiet.”
If you're really struggling to stay awake, is it okay to take a nap? “There are different points of view on this issue,” Cooper says. “If you chronically struggle with sleep, then I think you might want to stay up and go for a walk instead.” But if you sleep well, taking a nap is okay, says Lederle. “When we're experiencing a decrease in activity, it's a great time to take a short nap if you're dozing: 20 minutes to half an hour, no longer, and then your alertness will increase again.”
Is there hope for those of us who sleep in the evening? “You want to make the lights brighter in the afternoon to send alarm signals to your body,” says Lederle. Otherwise, “lean into it,” Patel says, and get ready early for another energetic day.
