HUMANS were not built to cross multiple time zones in metal tubes flying at 600 mph. Then again, we weren’t built for a lot of the things we do and enjoy – were foie gras and chocolate fondant on God’s mind when He created our digestive systems? I doubt it.<br /><br />Jet lag is particularly disruptive, as it throws off our circadian rhythms, which dictate times for eating, sleeping, hormone regulation and body temperature. When you enter a time zone of three or more hours difference, your body struggles to re-align these rhythms and the result is feeling disoriented, tired and often ill.<br /><br />With holiday season here, you don’t want to waste half your break being tired. Though we can’t beat jet lag – behold Pete Sampras, fresh from a flight from LA, yawning his way through Federer and Roddick’s penultimate set – we can take steps to overcome it. Jon Denoris, a fitness expert and consultant at Club 51 in Marylebone, specialises in helping business people get the most out of themselves through fitness and nutrition.<br /><br />“I work with a lot of people who can’t afford to suffer from jet lag,” he says. “I’ve found that 30 minutes is the magic time period to get people in the best shape possible for the day. It needs to be done as close to arrival time as possible, and in daylight, as natural light combined with exercise is a powerful resynchroniser.”<br /><br />Denoris finds that a brisk aerobic workout – depending on how fit you are – is the most effective way of stimulating catecholamines, the hormones that bolster alertness. <br /><br /><strong>BEAT ME BACK</strong><br />You don’t have to be a regular gym-goer to reap the benefits of Denoris’s programmes. One, which caters to business travellers that complain they never see the cities they travel to, is called Beat Me Back. You walk 15-20 minutes away from your hotel, then retrace your steps, trying to return faster than you walked out.<br /><br />If you’re going to use the unfamiliar hotel gym, Denoris has created an easy programme called 4,5,6 Reverse. You walk in, choose three cardio machines, and do four minutes on the first, five on the second, six on the third; then reverse and repeat, with six minutes on the first and so on. Do this twice and you’ve kept it interesting for yourself and your muscles, and fit a 30-minute cardio workout in. Finally, interval training is the most intense and effective: warm up for five minutes, then alternate periods of five minutes high with five minutes low intensity for a total of 30 minutes. You can sprint round the park, or treadmill, or even swim for life in the pool.<br /><br />To supplement your daily 30-minute cardio workout, Denoris recommends thinking about diet too. A carbohydrate-based meal can help induce sleep, while protein-based meals wake you up and will help with alertness. If you’re flying in from a night flight, go for bacon, eggs and yogurt for breakfast. If you need to sleep, go for pasta. “You can never eliminate jet lag,” reminds Denoris. “But combining exercise with the right mix of protein and carbs can make a big difference.” For a personal session with John, see www.clubfiftyone.co.uk. For the best jet lag busting treatments on your return to London, see the box on the right.<br /><br /><strong>IN-FLIGHT EXERCISES </strong> HELP BEAT JET LAG<br /><strong>SQUATS</strong><br />Keep the same position and do a few sit down-stand up squats.<br /><br /><strong>SHOULDER SHRUGS</strong><br />With arms at side (seated or standing) roll shoulders in a circular movement, both front and back.<br /><br /><strong>NECK STRETCH</strong><br />Perform easy, gentle neck circles to the right and then to the left<br /><br /><strong>ARM REACHES</strong><br />Reach both arms straight above your head and hold (sitting or standing).<br /><br /><strong>WALKING</strong><br />Walk up and down the aisles for a few minutes. You can vary your walk from a normal heel to toe walk, to walking on your toes or walking on your heels. Do this as regularly as you can.