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Have carbs had their chips? by Fiona Bugler Eating copious quantities of carbs is on page one of The Runner’s Rulebook. But are spuds, pasta et al really the best fuel for our performance, health and body-shape goals We need to reassess our relationship with carbs,’ says Laurent Bannock, a performance nutritionist and lecturer who works with both elite and amateur athletes (guruperformance.com). Eating lots of carbohydrates makes you good at metabolising them, explains Bannock – which sounds great until he adds ‘instead of fat’. ‘As an endurance runner you should be using body fat as your primary fuel source, so why do runners get obsessed with consuming carbs?’ Bannock is not alone in questioning the accepted carb doctrine. ‘Skilful marketing has made carbohydrate consumption a religion among athletes,’ says Professor Tim Noakes. ‘They believe that you cannot get energy from anywhere but carbs.’ Noakes – who as author of The Lore of Running (£13.43, Human Kinetics) can safely be classed as a running and sports science heavyweight – recently turned his thinking around on carbs and caused some controversy by advocating a Paleo-style diet (high-protein and low-carb, based on the meat-, nut-, berry- and veg-eating habits of our hunter-gatherer ancestors). For Noakes, it’s not just about performance, but health too. He argues that some people simply can’t metabolise carbs as efficiently as others. And for the carb-intolerant, eating large quantities won’t just limit fat-burning capacity, it will fail to properly fuel performance, and lead to weight and health problems. For him, the switch was driven by the fact that, despite clocking 200K a week as an ultra-runner, his weight was always an issue. He ate the traditional high-carbohydrate, low-fat diet that he had advocated for 33 years, but still ‘expressed his familial predisposition and developed type 2 diabetes’, he says. ‘There’s never reason to eat more than 200g of carbs a day,’ argues Noakes. ‘Some athletes eat 700g a day, and the probable outcome of such high-carb intakes in those with the genetic predisposition is the development of type 2 diabetes – as happened to me.’ Retraining your metabolism Even if you’re not carrying the carb-intolerant genetic hand, over-consumption of carbs, some argue, can negatively affect your running performance. ‘The body adapts and if you eat lots of carbohydrates, it will become good at metabolising carbohydrates,’ Bannock reiterates. ‘Your body will use the fuel it’s been given and initiate the carb management system. But to see improvements to your endurance-running performance, you need to retrain your metabolism to get your body used to becoming efficient at using fat as a fuel source – becoming fat-adapted,’ he continues. ‘Improving your ability to burn fat will preserve limited carbohydrate stores for when they’re needed (for instance, at the end of the race), and improving your metabolic efficiency will also boost your health.’ Noakes is reading from the same menu here: ‘Humans are designed to burn fat as the primary fuel during endurance workouts,’ he says. ‘That’s why we store so much of it in our bodies and relatively little carbohydrate. While one might argue that high-intensity exercise of short duration might be improved by a high-carbohydrate diet, the majority of people eating high-carbohydrate diets are involved in prolonged, lowintensity exercise for which fat is the optimum fuel.’ So how do committed ‘carbivores’ retrain their metabolisms to burn fat for fuel? ‘By eating less carbohydrate and more healthy fat, and timing it right,’ says Bannock. ‘It’s what you do on average that affects how your metabolism utilises carbohydrates. So make your daily plate contain 50 per cent starchy vegetables/fruit, and 25 per cent each of lean protein and healthy omega-3-rich fat.’ ‘Save the starchy carbs until after your workouts; eat 50 per cent carb/50 per cent protein up to an hour after your run. Then, after two hours, opt for protein, veg, fat and carbs in equal measures,’ explains Bannock. ‘Your body is like a fire, and just after you’ve trained the fire is burning, and this is the time to throw your carbohydrate logs on.’ Other experts agree on the potential performance benefits of limiting your carb intake. ‘New studies suggest it is possible to ‘train’ your muscles to use fat preferentially for fuel by consuming a low-carb diet,’ says Anita Bean, author of The Complete Guide to Sports Nutrition (£10.87, A&C Black). ‘Over time, the muscles will make more fat-burning enzymes and mitochondria,’ she explains. ‘Though low-carb diets will best suit those training for shorter races or those who are pre-diabetic [insulin-resistant].’ To take your carb-limiting strategy a stage further, consider the maxim of ‘train low, race high’. ‘Eating a low-carb diet in training and a high-carb diet 24 hours before a race gives you an advantage of having more fat-burning enzymes, plus more carbs as fuel for your muscles in the latter stages,’ says Bean. Also pay attention to your intake of energy drinks, which are very high in carbs with 30g or more per 500ml, ‘which you simply don’t need if you’re running at a moderate speed for less than 60 minutes’, says Bean. ‘Then, water is all you need to hydrate.’ Training your metabolism to be ‘fat-adapted’ means you ‘won’t need to ingest sugary sports drinks, because you have all the energy you need in your body’, says Noakes. ‘If you are carbohydrate-adapted, you will probably need to take in sugary drinks during exercise,’ he says. ‘But whether or not drinking sugary drinks during exercise is healthy is another question entirely: there is growing evidence that sugary drinks increase the risk of developing diabetes. Even one can of sugary drink a day is associated with an increased diabetes risk.’ Are you carb-intolerant? As touched on earlier, some experts argue that not all our bodies process carbs with the same efficiency. ‘There’s no one-size-fits-all rule,’ says Bannock. ‘We’re all unique, so nutrient needs are individual.’ Some can tolerate and utilise carbs more efficiently, and in larger quantities, while others can’t process them as effectively, and may end up storing the large quantities they consume as fat, negatively affecting weight and ultimately health. This is the key issue,’ says Noakes. ‘Clearly some athletes, such as the great Kenyan runners, are able to run very well when eating high-carbohydrate diets and it would probably be inappropriate to change their choice. This does not mean that everyone is able to metabolise carbohydrate as effectively as they are.’ So how do you know whether or not your body can tolerate those jumbo jacket spuds and super-size spag bols? ‘If, as a runner, you are clinically overweight with a body mass index greater than 25, you might be carbohydrate-intolerant,’ says Noakes. ‘And then all that carbohydrate is simply making you fat, not fit.’ ‘It’s easy to see if you are carb-intolerant,’ adds Bannock. ‘If you have extra fat – you can pinch more than an inch – and you eat a lot of carbs, the likelihood is that your body is not using the carbs you take in as fuel, but storing them as fat. Many runners are “skinny fat” – they’re storing more fat around their middle and, to a lesser extent, around the hips and thighs, which can signify carb-intolerance,’ he adds. Aside from the warning signs of weight and body fat, there’s another simple strategy to discover your body’s carb-metabolising efficiency. ‘Simply reduce the amount of carbohydrates you are eating and note the response,’ says Noakes. How does the menu change affect your body composition, performance and energy levels? ‘It needs to be a long-term change,’ warns Bannock. ‘You can expect to feel tired when you first stop eating high-carb meals, but after a few weeks you will notice a difference. A cyclist I’ve been training who ate nothing but carbs recently made the switch, and after just two weeks he got a PB Fear sugar and embrace fat As well as re-examining the volume of carbs we eat, it’s also important to recognise that not all carbs are created equal, and ensure the ones we do eat are of the right type. Slow-releasing, complex carbs are a far better option than simple, processed carbs, which have a high glycaemic index (GI). Usually ‘white’, these cause insulin levels to spike, meaning your body won’t use carbs efficiently and will store surplus as fat, making you less efficient nutritionally and impacting on your performance. To keep insulin spikes at bay, Bannock argues that you can look beyond the rice, pasta and spuds: ‘Eating fruit and non-starchy vegetables, such as broccoli, beans, carrots, peppers and spinach, should be more than sufficient to satisfy a runner’s carb needs. They are healthy fuel sources that will keep your muscles and energy levels topped up,’ he adds. Noakes goes a step further, recommending that the carb-intolerant avoid fruit altogether, while the rest of us ‘perhaps restrict the intake to a few pieces of fruit a week’. Unfortunately those simple carbs – especially sugar – have increasingly found their way into our general diets, often at the expense of the much-demonised ‘fat’. ‘Runners have traditionally opted for high-carb, lowfat diets,’ says Bannock. But in health and obesity terms, the high-carb/low-fat dietary strategy hasn’t worked for the general population. ‘Despite a reduction in fat intakes over the past 30 years, obesity rates have soared,’ says Bean. ‘Dozens of studies, spearheaded by scientists at the Harvard School of Public Health in the US, have found that low-fat diets are no healthier than moderate- or high-fat diets – and may actually be worse,’ she says. The food industry has cashed in on our desire to avoid fat, but products such as low-fat yoghurts are often laden with sugar. ‘Sugar is the real baddy and one of the principal factors in diabetes and metabolic diseases,’ says Bannock. Fat, it seems, has had a bad press, and our strategy of pushing it out of our diets to accommodate more carbs may be seriously flawed. ‘Fat has long been the scapegoat in the world of nutrition,’ says Bannock. But important new research suggests that runners need to eat quality fats for health and performance, while even saturated fats are no longer considered to be the malevolent force they once were. Guru Performance sports scientist Scott Robinson – who has worked with Everton FC, FIFA and Munster RFC – contends that the evidence against sat fats is limited. ‘In fact, contemporary research states quite the opposite,’ he says. ‘The fats you need to avoid are exactly some of those declared “healthy” by the various industry-funded heart foundations and include polyunsaturated – so-called “vegetable” oils which are, in reality, seed oils extracted only by industrial/chemical processes, and trans fats found in so-called “heart healthy” margarines and baked products.’ Robinson points to a recent meta-analysis of studies, published in the American Journal of Clinical Nutrition, which showed saturated fat intake is not associated with an increased risk of coronary heart disease or stroke. And in the journal Nutrition, research examining the average intake of saturated fat in 41 European countries and the age-adjusted risk of mortality from heart disease revealed that as percentages of saturated fat increased, rates of death from heart disease actually fell. ‘In fact, the fat from animals raised on pasture is probably as important for health as omega-3 fish oils,’ says Noakes Bean recommends that endurance runners eat 35-40 per cent of calories from fat, or 1.2-1.4g per kg of bodyweight. ‘Fifteen per cent of the fat should come from “healthy” saturates,’ says Bean. ‘Foods rich in “natural” fat are best: butter, milk, cheese, eggs, meat, fish, avocado, nuts, seeds and olive oil. But don’t forget to keep an eye on overall calorie intake to avoid weight gain.’ And don’t forget the protein… Another problem with a heavily carb-focused diet is that it may stop us consuming enough protein. And for runners, that’s really bad news. Many of us wrongly assume that protein leads to unwanted bulk, but its amino acids are recovery agents that are essential for rebuilding damaged tissue and refreshing muscles for the next time out. It also bolsters your immune system as your body needs plenty of protein to make infection-fighting white blood cells. Crucially, protein also lowers the glycaemic index of foods eaten with it, limiting the insulin-spiking effect of the carbs you eat. Which all explains why distance runners need more protein than most people, not less, says sports dietician Roberta Anding. ‘Getting enough protein protects your lean mass,’ says Anding. And that’s where your power comes from.’ Fish, chicken and red meat are classic protein sources, but by no means your only options. ‘Eggs and dairy products are incredibly high-quality protein sources,’ says Anding. Like meat proteins, egg, dairy and quinoa proteins are considered ‘complete’ because they contain all the essential amino acids needed to rebuild cells. Milk is particularly high in leucine, which has been found to trigger muscle recovery, and protein from eggs is especially well absorbed by the body. Another reason to re-examine your protein/carb balance is that ‘other valuable nutrients are often packaged with protein’, says Anding. Beef and dark chicken meat also contain iron, which helps in oxygen-to-muscle delivery. Cod, salmon and other cold-water fish deliver omega-3 fatty acids, which soothe aching joints and muscles, while dairy products bring calcium to maintain bones and stimulate muscle activation. If you, like many runners, are something of a carboholic, all this adds up to a pretty convincing case for taking a fresh look at the spuds, rice and pasta in your life. While it’s not time to ditch carbs altogether, you should try to ascertain how well your own body utilises them, consider the potential performance benefits of ramping up your fat-for-fuel system and look at the overall balance of your diet to ensure Mr Potato & Co are not pushing other essential nutrients off your plate. For some of us at least, the pasta party may be over. Eat More Chocolate! 26 June 2013 by Ashley Gartland Chocolate-loving runners have had a lot to celebrate in recent years. In 2011, the University of Cambridge reported that eating dark chocolate can lower rates of stroke, high blood pressure, and heart disease, thanks to its high concentrations of antioxidants called flavonols. The same year, a study published in the Journal of Physiology found that moderate chocolate consumption may cause muscle changes that improve athletic endurance. And a study published in 2012 discovered that people who eat chocolate frequently (at least a few times per week) weigh less than those who rarely eat it. No wonder runners go crazy for the sweet stuff! Of course, reaping these various health benefits hinges on eating the right type and amount of chocolate. “I generally recommend having 30 to 45 grams of dark chocolate per day, or roughly one tablespoon of cocoa a day,” says Dr David Katz, director of Yale University’s Prevention Research Centre and a noted chocolate researcher. Stick with dark chocolate that’s at least 60 per cent cocoa to get the highest concentration of healthboosting antioxidants, fibre, and magnesium. Unfortunately for fans of milk chocolate, its added fat and sugar content dilute the beneficial effects, says Dr Katz. It’s also key to stick with that 30-to-45-gram serving – and not eat the whole bar. Thirty grams pack 680 kilojoules and 11 grams of fat; eating any more can easily put you over your daily kilojoule limit and lead to unwanted weight gain. To help stretch your chocolate allowance, we’ve created four good-for-you desserts that offer the benefits of dark chocolate while keeping kilojoules and fat in check, so you can stay fit, run your best – and still satisfy that chocolate craving. You Crave: Chocolate bar If nutty, chocolate bars are your go-to treat, try making home-made dark-chocolate bark. Mix chopped dried fruit (like cranberries or currants) and nuts (such as walnuts, pistachios, or almonds) into melted dark chocolate and pour into a rimmed, wax-paper–lined baking sheet. (Reserving a handful of the mix-ins to sprinkle over the top of the bark provides a more visually appealing treat.) Once cool, break the bark into pieces. Or make chocolate the supporting player in a crunchy dessert by dipping a banana in melted dark chocolate and rolling it in chopped nuts. “Dark chocolate and nuts are great partners,” says dietician Monica Bearden, co-author of Chocolate: A Healthy Passion. “Together they provide vitamins, minerals, phytochemicals, protein, healthy fats, and arginine – an amino acid that works with the flavonols in chocolate to help dilate blood vessels and aid in muscle growth and repair.” Boost it: Add dried tart cherries to the bark to provide your body with a concentrated source of antioxidants. Research also suggests that tart cherries can reduce post-workout muscle and joint pain. You Crave: Brownies It’s not hard to make a brownie from scratch that’s more satisfying and nutritionally sound than your go-to boxed mix. The secret ingredient? Black beans. Typical brownies contain too much saturated fat, says dietician Claudia Wilson, but by substituting puréed black beans for half the butter in a recipe, you can create a dessert that’s still dense and moist, but higher in fibre and lower in fat. “With the rich flavour of the cocoa powder, you can’t taste the beans at all,” she says. “Just be sure to blend them in a food processor until they are completely smooth.” Don’t like black beans? Try the same trick using unsweetened applesauce or puréed prunes. Boost it: Use whole-wheat flour in place of refined, all-purpose flour to increase the fibre and nutrient content. Or try culinary nutritionist Sue Ann Gleason’s recommendation, and use a mix of flours that includes buckwheat; the gluten-free grain adds an earthy, nutty flavour, and diets that contain buckwheat are linked to a lowered risk of developing both high cholesterol and high blood pressure. (Whole-wheat and buckwheat flour available from health-connection.co.za) You Crave: Milkshake Classic chilly treats like milkshakes are notoriously high in saturated fat. Fortunately, you can easily lighten a milkshake by using fat-free milk or low-fat frozen yoghurt in place of whole-fat dairy. Bearden makes a sweet-tooth-satisfying and protein-packed shake using fresh fruit, skim milk, vanillaflavoured whey protein, Greek yoghurt, and a few tablespoons of antioxidant-rich cocoa powder. Gleason’s recipe blends together frozen bananas, raspberries, ripe pear, cocoa powder, Swiss chard, and coconut milk or coconut water. The addition of Swiss chard (or any dark, leafy greens) and coconut milk or water is particularly good for runners, since these ingredients are rich in magnesium, a mineral that may help relieve muscle cramps or muscle soreness. Boost It: Blend a tablespoon of your favourite nut butter into the shake to add healthy fats and protein. Or add a tablespoon of omega-3-rich seeds like ground flaxseeds or chia seeds. “Chia seeds are packed with high-quality protein, antioxidants, and minerals like magnesium, potassium, calcium, and iron, which help speed recovery and replenish minerals that are depleted during strenuous exercise,” says Gleason. You Crave: Pudding Single-serving pudding cups are actually a relatively healthy snack. But by making your own with one or two unexpected ingredients, you can create a more nutrient-dense (and dairy-free) alternative. Wilson makes a high-protein chocolate pudding by blending one 450g package of firm tofu, one cup soya milk, 1⁄2 cup sugar (or more to taste), up to 1⁄2 cup cocoa, one teaspoon vanilla, and 1⁄4 teaspoon salt. Gleason’s version ups the healthy fat and fibre with avocado. She blends 2 large peeled and pitted avocados with 1⁄4 cup cocoa powder, 1⁄4 cup pure maple syrup, and 11⁄2 teaspoons orange zest. Avocados also provide vitamins B, E, and K, and contain more potassium than a banana. Boost it: Add spices like cinnamon to build flavour in a home-made pudding. “Anytime you are able to use spices, you are getting more antioxidants and potent phytochemicals,” says Bearden. More Chocolate! Healthy uses for bars, bits, and cocoa powder 1. Chocolate chips and bars Select chocolate with 60 per cent or higher cocoa content or use unsweetened chocolate, which tastes bitter on its own but can be used in cooking or baking. Add bittersweet or unsweetened chocolate to Mexican chilli sauce. Stir into home-made braai sauce. 2. Cacao nibs Find these crunchy, slightly bitter nibs, which are essentially broken up pieces of cacao beans, at health stores. Sprinkle them on pudding or yoghurt. Add to trail mix. Mix into home-made granola bars. Top a homemade chocolate bark. 3. Cocoa powder Stick with all-natural cocoa powder, which contains more antioxidant flavonols than sweetened or processed cocoa powder. Stir it into your oats or morning coffee. Use it in home-made hot chocolate. Blend it into dry rubs to flavour meat.