Beat the afternoon slump

AAAAAhhhhhh, That infamous slump after a meal that wipes out your productivity and sabotages your evening workout, you know it all too well, don’t you?

This post-lunch drowsiness, where concentration plummets and energy fades away, isn't inevitable; it's something you can overcome with the right strategy.

We will break down the physiological mechanisms at play, particularly the impact of blood sugar and digestion, and help you feel energised, even in the early afternoon

Why do you feel tired after lunch?

Identify the real causes of your slump in 2 minutes. Discover what factors are sabotaging your afternoon energy.

Based on physiological mechanisms
Immediate personalised diagnosis
10 quick questions

Identify the causes of your fatigue

Answer these questions to find out why you feel low on energy after lunch

Your diagnosis

Answer the questions to uncover your causes of fatigue

Question Previous Next See my results Retake the quiz Your diagnosis Answer the questions to uncover your causes of fatigue Your main causes of fatigue Priority Actions What do you usually have for lunch? White bread sandwich, white pasta or pizza Proteins + refined carbohydrates (white rice, bread) Proteins + complex carbohydrates + vegetables Mixed salad or balanced light meal How long does your lunch usually last? Under 10 minutes (quick meal) 10-15 minutes 20-30 minutes More than 30 minutes How much do you eat for lunch? Very filling meal (I come away well satisfied) Hearty meal Moderate amount (I feel satisfied without being weighed down) Light meal Do you indulge in sweet desserts at lunchtime? Yes, absolutely (pastry, ice cream, cake) Often (3-4 times a week) Rarely (1-2 times a week) Never or fruit only Do you drink alcohol at lunch? Yes, regularly Occasionally Rarely Never How much water do you drink in a day? Less than 1L 1L to 1.5L 1.5L to 2L More than 2L How many hours do you sleep on average per night? Less than 6 hours 6am to 7am 7am to 8am More than 8 hours What do you do after lunch? I sit down immediately at my desk I stay seated but I move around a bit I walk for a few minutes I go for a 10-15 minute walk Do you expose yourself to daylight after a meal? No, I'm staying indoors Rarely Sometimes (2-3 times a week) Yes, every day Do you take a power nap after lunch? No, never I would like to, but I can't Yes, but more than 20 minutes Yes, a maximum of 10-20 minutes Blood sugar spike followed by crash Your diet is causing blood sugar rollercoasters. Fast sugars spike your insulin, followed by a sharp drop that drains your energy Heavy digestion Your meal demands too much energy for digestion. Blood flow is redirected to the stomach at the expense of your brain. Sleep debt Your post-lunch fatigue primarily indicates a lack of proper nighttime sleep. No dietary adjustments can make up for short nights Dehydration Even mild dehydration can impair your cognitive performance and increase fatigue. Your brain needs water to function. Post-meal inactivity Sitting down after a meal worsens lethargy. Your body goes into "rest mode" and digestion slows down, increasing drowsiness Lack of natural light Without exposure to daylight, your biological clock promotes the production of melatonin (the sleep hormone) in the middle of the afternoon. Alcohol consumption Alcohol is a sedative that slows down your nervous system. Even a single drink at lunch can undermine your alertness and performance Meal swallowed too quickly Eating too quickly prevents satiety from setting in and overloads your digestive system all at once, leading to immediate fatigue Your action plan These 3 factors are draining your energy. Read on to discover how to effectively address them and regain stable energy throughout the afternoon.

The key takeaways The post-lunch slump isn't inevitable; it's a response to a spike in blood sugar. To combat this, opt for a lunch rich in protein and slow-releasing carbohydrates, and steer clear of quick sugars. This nutritional mastery helps maintain your energy for a productive afternoon and an intense workout, turning a weakness into strength through simple dietary discipline.

Why do we experience that infamous post-meal slump according to science?

You may have felt guilty thinking you were just being lazy after your post-lunch fatigue, but that's not a sign of laziness. It's a complex physiological reaction that we, as athletes, need to understand in order to manage it. Let's put names to the culprits.

Post-Lunch Slump Timeline

Hover over the chart to understand what’s happening in your body

Post-Lunch Slump Timeline Hover over the chart to understand what’s happening in your body Blood Sugar Cerebral blood flow Energy Level Time (minutes) Level (%) 0-20 min Ingestion and Absorption Phase The meal begins to be digested. Carbohydrates are broken down into glucose. The pancreas detects the arrival of sugars and starts to secrete insulin to prepare for storage 20-30 mins Insulin and blood sugar spike Glucose floods into the bloodstream. Your blood sugar spikes, and you experience a temporary surge of energy. At the same time, insulin reaches its peak to handle this influx of sugar 30-60 mins Beginning of the energy slump Insulin does its job: it stores glucose. Your blood sugar starts to drop. Blood flow is redirected to the digestive system, depriving your brain of oxygen. Energy begins to noticeably decrease 60-120 min Glycaemic crash - The slump It's the trough of the wave. Blood sugar has dropped sharply (reactive hypoglycaemia). The brain is lacking its main fuel. Cerebral blood flow is at its lowest. The result: intense fatigue, collapsed concentration, mental fog. It's the infamous energy slump.

1st reason: digestion and circadian rhythm

The first mechanism is almost mechanical. A heavy meal, especially if it exceeds 1500 kcal, forces your body to redirect a significant portion of blood flow to the digestive system. It’s a matter of priorities. The problem? This blood is diverted from other organs, especially your brain.

Less blood means less oxygen for your neurons. The result is immediate: a mental fog, a lack of focus. Your brain, a major energy consumer (yes, we assure you, this applies to everyone). It goes into power-saving mode, much like you would do with your phone when you feel it's running low on battery.

But that's not all. A second factor comes into play: your circadian rhythm. Our internal biological clock schedules a natural dip in alertness, a slump that occurs between 1 PM and 4 PM. Therefore, the meal only amplifies a phenomenon that is already in motion. A true double whammy.

2nd reason: blood sugar levels and the role of insulin

So, we've looked at the biological reasons, but you also bear some responsibility for that urge to nap, and that's down to our dear friends, carbohydrates. A meal high in quick sugars — fizzy drinks, white bread, sweets — triggers a blood sugar spike. Your blood sugar levels are skyrocketing.

Your pancreas responds by releasing a massive dose of insulin to store that sugar. The problem is that this reaction is often disproportionate. Blood sugar levels then drop as quickly as they rose, causing a reactive hypoglycaemia. It's the crash.

Suddenly deprived of its main fuel, glucose, your brain goes into standby mode, takes a break, goes on strike, really. The consequences are immediate. And with that comes a a decline in cognitive performance of 30 to 35%.

Avoid the slump by managing your plate

Well, you should have grasped the mechanisms behind the "energy slump" by now. We can move on to taking action. Your energy levels are influenced by your diet, and every meal is a performance booster. Here’s a simple game plan for a flawless afternoon

Create the perfect breakfast for steady energy

Every ingredient should fuel your energy, not drain it. It's all about strategy.

The golden rule? Protein First. Lean meats, fish, eggs, legumes… They are rich in tyrosine, a precursor to dopamine, the neurotransmitter of alertness and motivation. A real booster for the brain.

Next, carbohydrates. But not just any carbohydrates. You need good carbohydrates for quality energy. Choose sources with a low glycaemic index that release energy gradually : sweet potatoes, quinoa, brown rice. They will provide you with lasting support without turning you into a zombie in the afternoon

Don't forget the quality fats, essential for satiety. Incorporate avocados, nuts, vegetable oils (olive, rapeseed) or fatty fish. An addition like some Omega 3 (fish oil) can make a difference.

Finally, it's all about fibre, fibre, fibre! And we're not talking about internet connections, but green vegetables. They slow down digestion and smooth out your blood sugar levels.

Anti-Fatigue Plate Builder

Create your perfect lunch and discover its impact on your energy

🥩 Protein

🌾 Carbohydrates

🥦 Vegetables

🥑 Fats

Glycaemic impact -

Low Medium High

Anti-Fatigue Plate Builder Create your perfect lunch and discover its impact on your energy Glycaemic impact Reset Protein Carbohydrates Vegetables Fats Low Medium High Grilled chicken Salmon Tofu Hard-boiled eggs Quinoa Sweet potato Brown rice White bread White pasta Broccoli Spinach Green salad No vegetables Olive oil Avocado Nuts/almonds No fat Add fibre-rich vegetables to slow down carbohydrate absorption A source of protein helps to stabilise blood sugar levels Good fats lower the overall glycemic impact Opt for slow-release complex carbohydrates Avoid refined carbohydrates that cause blood sugar spikes Your plate is well-balanced, well done! Select foods to see the impact

Foods to avoid at all costs at lunchtime

Knowing your allies is important. Identifying your enemies is crucial. Some foods sabotage your energy. Here’s the blacklist :

Heavy and greasy meals: Digestion takes up all your energy and causes a immediate lethargy.
Quick and refined sugars: Pastries, fizzy drinks, white bread… It’s the perfect recipe for a insulin spike followed by a glycaemic crash.
Alcohol: Even just one glass. It's a sedative. For an athlete, it's non-negotiable, as we saw on the impact of alcohol on bodybuilding.

Hydration and coffee alternatives

Last point: hydration. Dehydration, even mild, is a major cause of fatigue. Make sure to drink water regularly throughout the day.

As for the 4pm coffee, it may disrupt your sleep. Consider some smart alternatives : green tea, with its L-theanine, provides concentration without the jitters. Peppermint or liquorice herbal teas are also excellent options for a boost of vitality

14-Day Method to (try to) Beat the Post-Meal Slump

Tired of that mental fog dragging down your afternoons? I’m offering you a challenge: a two-week commitment to regain control. You’ll need a bit of discipline and consistency, the only path to achieving your goals lasting results.

Your daily game plan

The strategy is built on three simple and interconnected pillars. Each action sets the stage for the next, creating a cumulative effect. Stick to it and you'll see a significant difference. It’s a promise.

The strategic meal (Lunch): Apply the principles of a smart lunch. Aim for lightness: quality proteins, complex carbohydrates, and a good serving of vegetables. Eat slowly. Your digestion impacts your afternoon performance.
The dose of light (1:30 PM): Just after your meal, head outside. Your goal: capture the daylight for 10 to 15 minutes. This exposure is crucial for synchronising your biological clock and slowing down melatonin production
The digestive walk (1:45 PM): Follow up with a 10-minute walk at a moderate pace. The aim is toboost circulation and stimulate digestion, preventing your body from switching into "nap mode". For more in-depth information, check out resources like this article.

The progress tracking table: measure your gains

For a plan to work, measurement is essential. Self-assessment is the key to staying motivated and achieve measurable results. This simple tool will help you take charge of your transformation. Keep this chart updated. Every day. It’s what sets those who succeed apart from the rest.

Day	Meal adhered to (Yes/No)	Light output (Yes/No)	Walk for 10 minutes (Yes/No)	Afternoon energy level (out of 5)
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14-Day Tracking Chart Download your personalised tracking sheet in PDF format. Print it out and monitor your daily progress for 2 weeks. Download my PDF chart A4 Format • Ready to print • Daily tracking of your habits TRACKING TABLE - 14 DAYS Overcoming the afternoon slump Instructions Fill in this table every day for 2 weeks to track your habits and measure the improvement in your energy. Rate your energy level from 1 (very tired) to 5 (full of energy) Day Meal adhered to Light output Walk for 10 minutes Energy level (/5) Yes No

Other habits that drain your energy

Thinking that only your lunch causes energy slumps is a mistake. Energy is a complex and holistic system where lunch is just one adjusting variable. Other factors are ruining your afternoons. A little reminder never hurts:

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The quality of your sleep: the foundation of everything

Simple and straightforward: if you're not sleeping well, no dietary changes will save you. Sleep is the foundation to your recovery and energy levels, and overall good health. Poor sleep leaves you susceptible to fatigue, no matter how perfect your diet is

Advice: Aim for 7 to 8 hours of quality sleep. To achieve this, optimise your bedroom: a cool temperature of around 18°C, complete darkness, and turn off screens well before bedtime.

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The power nap: your ally if you can

It has now been 5 years since I started taking a 10-minute power nap after lunch, and it makes me more productive in the afternoon. Just remember to avoid exceeding 20 minutes. For me, 10 minutes is the ideal duration to recharge without falling into a deep sleep, give it a try on your end!

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Morning slump or deficiencies?

If fatigue hits you first thing in the morning, it's time to look elsewhere. Persistent fatigue may indicate something beyond just simple digestion, such as nutritional deficiencies (iron, B vitamins) that mimic chronic fatigue.

It's your turn: take charge of your afternoons

You now have all the information. Remember the three main rules: eat wisely at lunch by avoiding quick sugars, move after your meal (even a ten-minute walk is enough to get things going), or if you opt for a power nap (or do both!), and finally, respect your nighttime sleep. It's the non-negotiable foundation of your daily performance.