Matt Hart looks at some of the dieting options that you’ll be faced with if you’re want to shed a few kilos…
This isn’t an article about hunting for something you’ve lost, like the car key or passport loss—‘tis much more clever than that. It’s about deliberately losing body fat (the heavy wobbly stuff that will keep you alive a minute longer than the skinny good-looking fella treading water next to you, should the cruise liner you’re holidaying on strike an iceberg). I know this sounds like a radical concept, but the secret to successful fat loss is all about deliberately losing the blobby stuff whilst simultaneously having absolutely no intention of ever finding it again! Think of it like shaking off the flu or taking that really embarrassing jumper that your nana knitted to the charity shop and you won’t go far wrong…
It’s called ‘fat-loss’ as apposed to ‘weight-loss’ because many unsuccessful weight-loss plans result in loss of lean body tissue as well as fat. Losing lean body mass, which is essentially muscle, drives your metabolic rate down and reduces your capacity for physical work. A successful fat-loss program centres on the reduction of body fat levels with minimal disruption to your metabolic rate and energy levels. This all sounds quite fancy doesn’t it, but do you know what twenty years in the fitness industry has essentially told me about the secret to fat loss (not to mention that really hard Sports Science degree I had to endure where I was unwillingly force-fed all those cheap pints of beer in the student union)? Get ready for it. Eat less and exercise more! Yes, it’s flippin’ rocket science I tell ye…
Before we get into the science bit, perhaps we should consider why excess body fat is such a bad thing. I’ve already mentioned the only genuine advantage of carrying extra lard, so if you like going on cruises and are concerned about the ship sinking, could I suggest that you still follow the useful advice in this article and when it comes to booking the holiday, opt for the Caribbean where the sea’s a bit warmer (and avoid boarding any ships with names beginning with ‘T’ and ending in ‘itanic’).
So, if you’re not going to explore the polar ice caps or go on an imminent hunger strike, just think about what you’ll achieve by being a bit leaner. For a start, you’ll be able to ride up hills quicker. At Torq we regularly carry out fitness tests and one bit of data we present to folk is their power to weight ratio, which is expressed in ‘watts per kilogram’ of body weight. We test a rider’s maximum sustainable power in watts and then divide it by their bodyweight in kilograms and this gives us a figure. The higher this figure is, the more effective and ‘faster’ they are as a rider. The key point here is that it’s far easier to improve this ratio by losing weight, as opposed to gaining power. Lose weight and gain power and you’ll see a huge difference.
I hear it said all the time in the cycling world about a rider being a ‘good climber’. This conjures some rather disturbing images in my brain. I see a Golum-like mountain goat creature with really overdeveloped hind legs and scrawny long fingers that’s kind of like Darwin’s answer to what a ‘really good climber’ should look like. The reality is actually down to how much power a rider can produce and their body weight. Muscle produces power and fat does not, so the chances are that if you’re lean and you do a lot of cycling, you’ll be a good climber compared to your lardier buddies.
With less body fat you’ll also be able to stop, change direction and accelerate faster—all significant points for a mountain biker. Lighter riders can get away with lower tyre pressures without pinch flats, and that means better traction for cornering and climbing up slippery stuff. Furthermore, you’ll go through fewer brake pads and bust less stuff. All in all you’ll feel better on the bike and ride better too. Hopefully this provides enough motivation to fight the flab!
Okay, now for the science. It’s not difficult science, but it’s science nonetheless. If you’re only going to lose weight you must create a negative energy balance. This means that you must have less energy going in (calories from food) than you’re using up (basal metabolic rate plus activity). If your energy-in equals your energy-out you’re said to be at ‘energy balance’ and you’ll stay the same weight. On the other hand, if you consume more calories than you use up you’ll put on fat and this is called a ‘positive energy balance’.
If you want to be successful in your fat-loss campaign, don’t be in a rush. You should be looking at creating a slight negative energy balance, which is something you’ll be able to stick to long-term, rather than the ever-popular crash dieting strategies sold to us by the mainstream media. Crash dieting is unlikely to work long-term for various reasons. The motivation for rapid weight loss is short-term in nature anyway because it centres on a ‘quick-fix’ philosophy. This invariably leads to the roller-coaster of emotions that typifies the ‘yoyo dieter’ – determination to diet, rapid weight loss, weight-loss plateau, loss of determination, return to old habits, rapid weight gain, guilt, new determination to diet, rapid weight loss… and so it goes on. Most people put excess fat on slowly and progressively over time (called ‘creeping obesity’), so it’s totally unnatural and very difficult to lose fat quickly. All you’ll lose through crash dieting is a whole pile of muscle and water.
Creeping obesity sounds a bit harsh doesn’t it? Well, it’s a clinical term, not a phrase I’ve made up in an attempt to belittle you. It’s actually a big problem in the Western world and centres on the culprit (most of us) eating slightly more calories than we should do on a daily basis. At the end of a week, you can total these daily calories up and it adds up to, well—quite a lot of calories. Then look at your monthly total and it’ll be visible on the scales. Just so you know, there are nine calories per gram of fat, which means that a kilo of fat is 9,000 calories. Not surprisingly, it’s amazing how much easier it is to over-consume than under-consume 9,000 calories.
So, let’s assume that your fat stores are either creeping upwards or are stable but at a level you want to reduce for all the fabulous reasons highlighted above. How do you lose it?
This is an extreme example, yet it demonstrates rather well why you shouldn’t starve yourself. If you don’t have any food coming in, your carbohydrate stores will run out pretty quickly, because of their very limited supply within the muscles and liver. Once this runs out, you’re left with fat and protein as fuel sources. In preference to using its fat stores, the body will metabolise protein for one logical reason. Protein constitutes the structure of our muscles and organs, all of which are living tissue, requiring energy to simply ‘exist’ at rest. By whittling down these structures in return for energy, the resting metabolic rate of the body is reduced. With little or no calories entering the body, this is a survival mechanism that works pretty well, because energy is produced through a process that also reduces the metabolism, enabling you to survive for longer without food.
This is why starvation diets don’t work, because when you stop eating, you lose loads of weight (muscle) and then when you get fed up (or think you’ve reached your goal weight), you start eating again. However, because your metabolism is suppressed, you initially store loads of fat, the muscle goes back on and ultimately you end up heavier than you were when you started.
Fat Loss for the Active Person
In order to hold on to your muscle when you’re at negative energy balance, guess what? You need a diet rich in carbohydrate. Carbohydrate is said to have a ‘protein-sparing’ effect, because in its absence, protein will be converted to carbohydrate through a process called ‘gluconeogenesis’ to enable your metabolism to run smoothly. In the absence of adequate dietary protein, your muscles get the chop! So, your first line of defence is to maintain a regular intake of carbohydrate to discourage protein metabolism. You’ll also want to ensure you get some quality protein sources too, so that any stray protein metabolism comes from your food and not your hard-earned muscle.
In order to create your negative energy balance and encourage fat loss, it goes without saying that you should look at keeping your dietary fat intake as low as possible—this is after all the stuff you’re trying to get rid of. At rest, most of your energy comes from fat, so if you’re not putting it into your body, you’ll be using the fat stored around your organs and under the skin to fuel your metabolism. Any calorie you put into your body that is excess to requirements will be stored as fat though, so losing fat isn’t just about a following a low-fat diet, it’s about following a low-fat diet with a slightly negative energy balance.
So apart from sparing protein and preserving a high basal metabolic rate, enabling you to burn more fat at rest, carbohydrates will provide you with the capacity to exercise effectively and at length. A diet of similar calorific value with a greater percentage of fat or protein will reduce your capacity to exercise, and isn’t a logical choice for the cyclist wanting to lose fat.
Go the Good Carbs
To further enhance the effectiveness of your fat-loss program, a little knowledge of the glycaemic index (GI) will help. The GI is a measure of how quickly the glucose from the food we eat gets into our bloodstream. It’s all measured against glucose, which is 100 and just about the quickest. Basically, the lower the GI, the longer the carbohydrate lasts, because it drip-feeds the metabolism and the less likely it is to be stored as fat. Big influxes of glucose from high GI foods force fat storage in the body’s attempt to reduce blood sugar. Low GI foods are more satisfying and unlikely to leave you craving for more. They tend to be quite bulky due to their fibre content and generally contain less calories per serving.
Very active people should choose high GI foods immediately after exercise to aid carbohydrate storage, but if your aim is fat loss, at all other times you’re better off going for low GI as much as possible. The mistake that many people make is thinking that low GI foods are always the starchy carbohydrates, but this isn’t necessarily the case. Fructose (fruit sugar) for instance has an extremely low GI, yet is intensely sweet. You can’t get more ‘starchy’ than a baked potato, yet these have a GI that’s right at the top of the scale. Do your research. There are plenty of books out there as well as information on the internet.
Don’t Forget to Exercise!
It goes without saying that the more exercise you do, the more calories you’re going to burn, so whilst you’re sorting out what you’re eating, don’t forget to look at your weekly schedule and see if you can find a bit more time to get out on your bike. The most effective form of fat-loss exercise is prolonged steady low intensity exercise, because this burns more fat, but it requires time—a commodity many of us just don’t have. If you have all day, low intensity exercise is very effective. If you have limited time, you’re better off working harder for the time you have.
If you can use the gym a couple of times during the week for instance, try to maximise your time there and don’t just stick to a steady pace in the belief that you’ll burn more fat. Ultimately, the more calories you can burn during a workout, the greater you’ll tip your energy balance to the negative. Higher intensity workouts during the week will boost your fitness too, giving you more power under the hood when you’re riding the bike at the weekend.
You should also look at incorporating some upper-body weights exercises into your routine too. Weights of high repetition and light resistance will develop muscle density. Muscle is a living tissue, so the more of it you have, the greater your resting metabolism and the more fat you’ll burn at rest. Get the picture?
High Protein or High Carbs?
‘Dieting’ is a massive industry and there’s a whole barrow-load of different opinions out there, but two that really contrast are the traditional ‘high carbohydrate’ approach to fat loss, which I have outlined thus far and the more recent ‘high protein’ viewpoint endorsed by the famous Dr Atkins. There are of course diets that sit somewhere between the two like ‘The Zone’ and ‘Body for Life’. With celebrities attributing their new-found svelte physiques to a high protein diet, you’d be mad not to try it—wouldn’t you?
Pro-protein protagonists put forward a very convincing case for following a diet that’s low in carbohydrate and high in protein. Here’s a summary of their main points:
• Some research suggests that a high protein diet is better at maintaining a high resting metabolic rate than a high carbohydrate diet of the same calorie intake.
• One piece of research has also demonstrated an 11% increase in fat loss with a high protein compared to high carbohydrate diet.
• High carbohydrate diets have been found to encourage insulin production following a meal, which has been linked to a greater potential to store fat.
• High carbohydrate diets have been linked to increased ‘seratonin’ release (a hormone that controls mood) and it is suggested that individuals overeat carbohydrate-rich foods in order to provide the brain with its ‘seratonin fix’. The argument is therefore that high protein foods increase feelings of satiety.
• It is theorised that dieters will just eat more when they know a food is ‘low-fat’ or ‘diet’ (low fat usually means high carbohydrate). One study showed that when given crisps with no nutritional information, the subjects of the experiment ate on average 61 calories worth. After being informed that the product was fat-free, energy intake rose to 111 calories.
Conversely, here are some of the arguments against high protein diets for fat-loss:
• Very low carbohydrate diets cause glycogen stores to be lost along with the water they hold. These diets also stimulate a process called ‘ketosis’ where the body tries to form an alternative fuel source to carbohydrate. Ketones are highly toxic, so are excreted in the urine causing additional water loss. It is argued that this combined water loss causes weight loss, often misinterpreted as fat loss.
• Ketosis causes bad breath, nausea and if you don’t drink enough water, it can kill you!
• One piece of research comparing the ‘Zone’ diet with a high carbohydrate diet demonstrated that both produced equal amounts of weight loss, yet the Zone diet raised harmful triglycerides in the blood to dangerously high levels.
• High protein diets are typically very low in fibre. The scientific evidence clearly points to the incidence of colon cancer being lower in populations consuming diets high in fibre.
• Many pro-carbohydrate bodies suggest that the high protein approach simply represents yet another low-calorie diet. The smaller the range of foods available, the lower the calories consumed. Removing carbohydrate from your diet also removes the temptation to add fat to food—where are you going to put your butter or cream?
• High protein diets stimulate calcium loss, reducing bone mineral density and increasing the risk of fractures/osteoporosis.
• Low glycaemic index (GI) foods provide a gradual release of carbohydrate into the bloodstream encouraging only low to moderate insulin levels. Here the argument is that these foods are the most satiating, not protein.
• For the past 10,000 years our ancestors survived on a high carbohydrate and low fat diet. They ate their carbohydrate in the form of beans, vegetables and whole cereal grains. They ate their sugars in fibrous fruits and berries. Technology-simple cultures still have similar eating habits and are free from many of the diseases that plague industrialised societies.
Let’s be Sensible!
How physically active are you? Do you ride your bike every day or just on weekends? Do you want to ride at a reasonable speed, or are you happy just pottering along? When push comes to shove, losing weight is all about creating a negative energy balance. This means that you need to have less calories going into your body than you push out through metabolism and activity, and there are plenty of ways of achieving this. You need to make a choice that is both healthy, workable and one that sustains enough bodily energy for you to get on with what you want to do in life.
If you exercise intermittently and want to have a bit of zip in your legs, you should be able to get away with elevating your carbohydrate intake the day before you exercise. If you’re regularly physically active though, choosing a low-carbohydrate diet can only spell disaster. Your glycogen stores will be completely stripped of content and your capacity for exercise will be severely restricted.
To quote Dr Dan Benardot (Nutrition for Serious Athletes - 2000), “While the high-protein, high fat, low carbohydrate diet has reared its ugly head once again (it seems to return with a new name every 10 to 20 years), it is no better now than it was when it was first introduced. There is nothing in science or experience to suggest that this type of intake is useful for any athlete. For endurance athletes, all the literature makes it amply clear that the higher the carbohydrate intake, the better the performance.”
What is Healthy?
In terms of general health, again I can only offer my point of view, and of course there are many other opinions out there. I truly believe that a low fat, high carbohydrate diet is healthy, regardless of activity level as long as every effort is made to consume low-glycaemic index (GI) foods as the mainstay of your diet. These are typically unrefined whole grain cereals, pulses (beans and lentils etc), oats, pasta, brown or basmati rice and fruit/vegetables. I also firmly believe that the vegetarian regimen is very healthy one and that diets high in saturated fat are primarily responsible for the high levels of heart disease in the Western world. I’m not adverse to the suggestion that refined high GI carbohydrates can play a role, but more so when combined with an appropriate level of exercise.
I also feel that diets high in monounsaturated fat (with things like olive oil), typical of the Mediterranean region, are healthy. The evidence for this is in the extremely low incidence of heart disease for these regions (the sun and lack of stress probably helps a tad), but I don’t consider this kind of diet the ideal springboard for fat loss. Nor do I believe they’ll fuel you to do anything more than trundle when you are on the bike. With regard to the high protein diet, my major health concern would be the lack of dietary fibre, which could lead to various unhealthy complications.
I wouldn’t have spent so much time at the beginning of this article covering the importance of carbohydrate for physically active people if there wasn’t a mountain of validated research supporting it. It’s important to understand the debate before you make any decisions, but my overriding message is ‘keep it simple’. If you stick to a negative energy balance and persevere, you will succeed. Good Luck!
Matt Hart is a coach and the director of Torq Fitness in the UK. If you want to obtain more comprehensive information on this topic and others relating to training and nutrition, Torq are currently offering free electronic copies of their 52-page ‘Performance Resource’ to Mountain Biking Australia readers. Just send an e-mail to firstname.lastname@example.org requesting the free Torq Performance Resource. If you would like a hardcopy of this brochure, it sells for $12.50 and can be ordered direct from the Torq website www.torqaustralia.com.au