Why Jet Lag Disrupts Business Performance

Jet lag is more than feeling a bit tired. For business travellers, it can mean walking into a meeting with a foggy head, struggling to find the right word, or making a poor decision because your body clock is still in another time zone. The UK's position as a global aviation hub means many professionals regularly fly east to the Middle East and Asia, or west to North America. Each direction brings its own challenges. The good news is that jet lag is not inevitable. With a few deliberate steps around sleep, hydration, and light exposure, you can arrive refreshed and ready to perform.

This guide is designed for the practical business traveller. It focuses on what works, based on how the body's internal clock responds to light, food, and activity. No gimmicks, just sensible strategies you can use before, during, and after your flight.

Pre-Flight Adjustments: Sleep and Light

The most effective way to reduce jet lag is to start before you leave the UK. Your body clock, or circadian rhythm, takes its cues from light, but it can be nudged in advance. For a few days before departure, shift your sleep and wake times towards your destination's schedule.

• Eastward flights (e.g. to Dubai, Singapore, Tokyo): You need to advance your clock, so go to bed and wake up earlier. Aim for 30–60 minutes earlier each day.
• Westward flights (e.g. to New York, Los Angeles): You need to delay your clock, so go to bed and wake up later. Again, shift by 30–60 minutes daily.

Light is your strongest tool. In the morning UK time, get outside for 20–30 minutes if you're flying east. Avoid bright light in the evening. If you're flying west, seek evening light and dim your mornings. A brisk walk under a cloudy sky still helps; you don't need sunshine, just daylight.

Also, set your watch to the destination time as soon as you board. It sounds simple, but it helps you mentally commit to the new schedule.

In-Flight Tactics: Hydration, Movement and Rest

Cabin air is dry, and the pressure and noise add stress. Your main jobs in the air are to stay hydrated, keep blood moving, and sleep at the right times.

• Hydration: Drink water steadily. A good rule is 250ml for every hour of flight. Avoid alcohol and limit caffeine, as both disrupt sleep quality and hydration. Herbal tea or just still water is best.
• Movement: Get up every hour or two. Walk the aisle, do calf raises, ankle circles, and gentle stretches. Compression socks can help prevent swelling and reduce the risk of clots on long-haul flights.
• Sleep strategy: If you're arriving in the morning at your destination, try to sleep on the plane so you can stay awake all day. If you're arriving at night, stay awake on the plane and sleep when you land. Use an eye mask, earplugs, and a neck pillow to make rest more likely.

Don't forget to moisten your skin and eyes. A simple saline nasal spray can ease dryness. And if you wear contact lenses, switch to glasses for the flight.

Arrival Strategy: Light, Naps and Meal Timing

What you do in the first few hours after landing can make or break your trip. The goal is to sync your body clock to local time as quickly as possible.

• Light exposure: If you've flown east, get morning light. If you've flown west, get late afternoon and evening light. Spend 30 minutes outside, without sunglasses, if safe. This tells your brain it's daytime.
• Naps: If you're exhausted, take a short nap of 20–30 minutes, no longer. A long nap will make it harder to sleep at night. Set an alarm.
• Meals: Eat at local meal times, even if you're not hungry. This helps reset your digestive clock. Choose lighter meals with protein and vegetables. Avoid heavy, rich food that can leave you sluggish.
• Activity: A gentle walk or a light workout in the hotel gym can boost alertness. Avoid intense exercise late in the evening, as it may keep you awake.

Caffeine can be useful, but time it carefully. A coffee in the morning local time is fine; a coffee after 2pm may interfere with your sleep.

The Return Journey and Short-Haul Realities

Coming home to the UK brings its own adjustments. After a westward trip, you'll need morning light to reset. After an eastward trip, you'll need to avoid early morning light and seek evening light for a day or two. Try to get back into your normal routine as soon as possible.

For short trips of two or three days, full adjustment is unrealistic. In these cases, prioritise performance over perfect circadian alignment. Stay hydrated, use strategic caffeine, and accept that you may feel a little off. Some travellers choose to stay on UK time for very short trips, but this often backfires because meetings and meals are at local times. A better approach is to adapt as much as you can, then recover properly at home.

Finally, remember that jet lag is cumulative. If you're a frequent flyer, build in rest days after long-haul trips. Your body will thank you, and your work will benefit.