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Aerobic fitness change can be estimated by a sub-maximal fitness test (see Appendix B). Equipment required for this test is a stationary bike, a heart-rate monitor and a rating of perceived exertion scale. The test lasts only about 10 minutes with a 4-minute cool-down and can be performed every month to assess exercise heart-rate change. Three bike protocols for unfit, moderate and high fitness individuals are described overleaf. All that is required is for you to perform the exercise protocol as described, and to record your heart rate and rating of perceived exertion at the end of each exercise stage. As can be seen, this submaximal test involves a 4-minute warm-up, an easy 3-minute cycling stage, a medium-hard 3-minute cycling stage and a moderately hard 3-minute cycling stage. The test should not be too tiring and it is important that your exercise heart rate does not go too high.

After you have finished the test, you should have your resting and exercise heart rates recorded, together with your rating of perceived exertion at the 3 stages. You can then plot these data on the graph included in Appendix C. You should see your heart rates increase during the 3 stages after the warm-up. If you are nervous and consequently have a high resting heart rate, your heart rate for stage 1 and 2 may be similar. When people get accustomed to the test, however, they typically get a consistent rise in their heart rate across the 3 stages.

Analysing the heart-rate response to submaximal exercise after 3 interval training studies conducted in our laboratory, we found that a decrease in the average heart rate by 1 beat at stages 2 and 3 equalled an increase in aerobic fitness of about 1%. Thus, after doing interval sprinting for 6 weeks, if the average heart rate at stages 2 and 3 was lowered by 4 beats per minute, the increase in aerobic fitness would be about 4%. Your heart rate will continue to decrease and you will get fitter if you either increase your pedal rate or resistance over the following weeks of exercise. For example, an average decrease in heart rate of 10 beats per minute for stages 2 and 3 equates to an increase of aerobic fitness of about 10%, and a decrease of 20 beats per minute about 20%, and so on.

The lowered heart rate during exercise reflects adaptations in the heart, the muscles and the blood; it is not possible to have an increase in aerobic fitness without a lowering of heart rate at the same bike power outputs. A monitoring form to record all this information is included in Appendix F. You can copy the form and record this information every week for 6 weeks. Other information can be recorded on the weekly record form located in Appendix G.

On the following pages are examples of a morning, lunchtime and evening interval sprinting weekly program, performed at light, moderate and hard interval sprinting intensities. You should choose the method and exercise intensity that is best for you. You might also choose to exercise 2 mornings per week and once at lunchtime or in the evening.

What about exercising on the other days? It is likely that performing more interval sprinting exercise, either by increasing the length of each session, say, from 20 minutes to 30 minutes, or by including more sessions, such as adding 20 minutes of interval sprinting on a Sunday, will result in greater adaptations, such as reduced belly fat, increased aerobic fitness, decreased insulin resistance and increased leg and trunk muscle mass.

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This chapter has described interval sprinting techniques and modalities. The key points to remember are:

• For best results, it’s important to perform interval sprinting correctly by determining your optimal pedal rate and pedal resistance.
  
• Interval sprinting can be performed successfully by a number of patient groups, provided they consult their GP and/or an exercise physiologist prior to beginning their program.
  
• It is important to monitor your interval sprinting performance and the health changes that are likely to occur with regular interval sprinting, so you can measure the amount of belly fat you lose.
  

Now that you know how to choose the right equipment for interval sprinting and how to use it to get the most benefit from your program, let’s look at adopting an eating plan that enhances your exercise program and helps you lose belly fat.

Why we have we become overweight

The last 50 years have brought an excessive abundance of high-energy processed food and a significant decrease in physical activity to our lives. Fat-inducing factors of the modern diet include increased consumption of sugar, high levels of saturated fat, increased use of unhealthy vegetable oils and inadequate consumption of fibre and the healthy fats found in foods such as olive oil, fish oils, avocado and coconut. Our bodies are very good at storing fat and poor at burning it up because for most of our evolutionary history we have never been faced with an abundance of food, and unfortunately modern processed foods tend to put the body into fat-storage mode as opposed to encouraging cells to burn fat. We’re also moving less, because most of us sit down all day at our computers. Even our children don’t move as much as they used to, thanks to a decrease in the amount of physical activity they engage in both at school and as recreation. As discussed in Chapter 5, increased levels of daily stress and reduced quality of sleep also affect fat gain.

To counteract these negative factors of modern living, we need to adapt a healthy eating regimen. The healthiest way of eating is based on consuming lots of fruit and vegetables and little processed food, a diet commonly known as the Mediterranean eating plan.

Our hunter-gatherer genetic legacy

The agricultural revolution occurred some 10,000 years ago, but human evolution began some 2.6 million years earlier, in the Paleolithic period.
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This means we still carry a relatively unchanged ancient genome. Although we live in the 21st century, from a genetic perspective we are Paleolithic people. When hunter-gatherers adopted a diet based on grain, their health quickly degenerated, and this decline in health is prevalent today as lifestyle diseases continue to dominate Westernised and developing nations. We eat highly processed synthetic foods with up to 3 times less fibre, half as much polyunsaturated and monunsaturated fats, 4 times less fish, 60–70% more saturated fat, 3 times more protein and up to 5 times more salt and sugar. Our problem is that our DNA has evolved in an environment of food scarcity, yet today we are immersed in an overabundance of inexpensive, processed, unhealthy food. Over centuries, our bodies have become very good at storing fat and until recently had never faced the problem of being overweight. Modern humans typically eat an excess of high-energy processed food and are unable to use up these extra fat stores.

The problem with modern processed foods

Sugar

Weight-inducing factors of the modern diet include increased consumption of sugars in general, and of fructose in particular. Fructose is a simple sugar that does not cause a high rise in blood sugar, so it was once recommended as a substitute for sucrose. While the body needs small amounts of fructose, too much overwhelms our liver. In developed countries, fructose now makes up a significant part of what we consume: it comprises about 10% of the average Western diet. When we eat excessive fructose, the liver’s ability to metabolise it is diminished. Overwhelmed with fructose, the liver converts this sugar to fat and distributes the fat, in the form of triglyceride, into the circulation. Fruit and vegetables have small amounts of fructose, but food manufacturers also add lots of fructose to a wide range of foods. Much of this added fructose comes in the form of high-fructose corn syrup, which is very inexpensive. The problem is that fructose does not satisfy our appetite – in fact, fructose makes us feel hungry. Food manufacturers know that when they add fructose to a food, people eat a lot more of it. Consequently, excess fructose consumption is associated with fat gain.

Almost all packaged foods have some added sugar. In some countries you can check for added fructose by examining the labels of packaged foods; however, many countries do not differentiate between the different types of sugars on their labelling. Be particularly wary of soft drinks, as they are usually full of fructose, and even fruit juice usually has a lot of fructose – minus the healthy nutrients of whole fruit. All soft drinks should be eliminated from your eating plan and fruit juice consumed sparingly. As an example, a cup of chopped tomatoes has about 2.5 grams of fructose, a can of regular soft drink about 20 grams, and a super-size cola about 60 grams.

Fat

The second dangerous aspect of the modern diet is our tendency to eat the wrong kinds of fats. Consume healthy, monounsaturated fats and you will boost your body’s fat-burning ability, but eat unhealthy, saturated or polyunsaturated fats and you will likely gain body fat.

Saturated fat is a hard fat and is contained in butter and meat. A US study conducted on men and women aged 55–75 years tried to determine if eating saturated fat contributed to belly fat accumulation. Subjects kept a food diary and underwent magnetic resonance imaging (MRI) to assess their belly fat. Results showed that those who ate the greatest amount of saturated fat also possessed the largest belly fat stores. Men and women who consumed more than 30% of their calories in the form of saturated fat had high levels of belly fat, so it’s reasonable to expect that consuming lots of saturated fat in your diet increases the risk for accumulation of belly fat.

Vegetable oils are also troublesome, as they are full of polyunsaturated fatty acids that go rancid quickly. During preparation for the market these oils are typically heated and have solvents added and can also be exposed to air and sunlight. This processing destroys their nutritional value and also creates oxidants, which are dangerous for health. Canola, corn, safflower, soy and sunflower oils are among the most highly refined polyunsaturated oils. Also, polyunsaturated oils have been shown to slow down the thyroid gland and thus encourage fat gain. You should not heat any vegetable oil. Use coconut oil (a saturated fat) but don’t heat to a temperature higher than 160°C. Coconut oil is full of saturated medium-chain fatty acids. It is unusual among saturated fats because studies have shown that natural coconut oil encourages fat burning, prevents certain diseases prevention and has anti-ageing properties. The medium-chain fatty acids in coconut oil go straight to the liver, rather than into the circulation, where they influence enzyme activity and induce fat burning. In contrast, long-chain fatty acids are typically stored as body fat. Coconut oil is also antibacterial and is very good for the skin. Coconut oil can be used for stir-fries, however the best way to stir-fry is to use no oil at all. Coconut butter is also an excellent substitute for butter and margarine. You can buy coconut oil in health stores, and there are numerous websites with recipes using coconut oil.
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Olive oil is another excellent fat that has proven health benefits. Your olive oil should be as fresh as possible, stored in the fridge, and kept away from sunlight. Buy small bottles and change them every 3–4 weeks. Make sure to buy local so that transit time is reduced.

Don’t forget about fruits with high antioxidants, like avocado and papaya. Avocado has more fat than any other fruit, and, like olive oil, it is mainly in the form of healthy monounsaturated fat. Avocados are versatile and can be eaten as a snack, as a dip, added to a spicy pasta sauce or sliced on top of grilled chicken breast. They should be eaten raw.

Finally, omega-3 polyunsaturated fatty acids found primarily in oily fish have proven health benefits. Interestingly, it has been estimated that the great majority of people eating processed food diets are omega-3 deficient. Omega-3s in the diet can protect against cardiovascular heart disease, positively alter blood lipids, increase cardiac properties and vascular function and decrease inflammation.
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The main chemicals in omega-3s that are thought to enhance health are eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids. A number of plants and vegetables contain EPA and DHA, such as Chinese broccoli, flaxseed and spinach, but the highest amounts are contained in oily fish such as tuna, salmon and mackerel.

Protein

The third dangerous aspect of the modern diet is that we tend to eat too much of the wrong kinds of protein, namely red meat. For years, the food industry has convinced people that we must consume their products to get all the protein we need to be healthy. Protein, as the advertisements correctly point out, is an essential nutrient, but this emphasis on protein has created the idea that the only source of protein is from animal products. In Western societies, meals are primarily focused around meat. Our obsession with getting enough protein and eating animal products at almost every meal has created a situation of protein overload.
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The notion that the only source of protein is meat and dairy is not true. In fact, all plant foods contain protein and it is possible to get all the protein you need from a strict vegetarian diet.
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Consider the paradox whereby a cow grows quickly from a 20kg calf to a 360kg steer simply from the grass it eats.
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It doesn’t eat chicken or steak to get its protein. Even bigger is the African elephant, also a vegetarian. We do not need to eat meat or dairy products every day to get our protein, and the great majority of people who eat a lot of meat consume far too much protein.

Eating high levels of animal protein can cause health problems.
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If we eat too much meat instead of vegetables, we are depriving ourselves of vital plant nutrients. Studies have shown that people who eat meat have twice the chance of dying from heart disease, 60% more chance of dying from cancer and 30% more chance of dying from other lifestyle diseases. There is now a plethora of research evidence supporting the health benefits of an unprocessed, plant-based diet. For example, it is now possible to create images of damaged heart arteries and then show that a plant-based diet reverses arthero-sclerosis. Ingesting meat proteins increases blood cholesterol levels in humans to a greater extent than consuming saturated fat. When diets of different countries are compared, results have shown that people consuming traditional plant-based diets experience significantly lower incidences of heart disease. In Westernised countries, people who consume more plant-based foods also have reduced incidence of heart disease. Vegetables such as asparagus, cauliflower, spinach, mung beans and broccoli have high levels of protein.
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Nuts are also a great source of both protein and healthy fats. Almond, hazelnut, brazil nuts and cashews are all excellent sources of nutrition and are great to snack on when you feel hungry between meals. All nuts should be raw and free from any additive, such as salt.

Fibre

The fourth dangerous aspect of the modern diet is that we tend to eat too little fibre. Fibre is that portion of food that cannot be digested by enzymes in the human digestive tract and so does not provide any nutrients, but it plays a key role in regulating bowel activity. Nutritionists recommend that we eat at least 30 grams of fibre daily; unfortunately, most people in Western cultures only consume about half this amount. Fibre was first found to be important when physicians working in Africa noticed that those individuals who remained on traditional diets enjoyed very good health, but when they began eating refined grains and sugars, their health deteriorated. This discovery became known as the fibre hypothesis.

Studies have shown that those people who consume the most fibre have the lowest incidence of colo-rectal cancer. It has been estimated that if Americans increased their fibre intake by 13 grams a day from food sources – not as a supplement – about a third of all colorectal cancer in the USA could be avoided. However, it is not clear if this colorectal cancer prevention is solely due to high-fibre foods, because people eating this type of food typically eat less meat. Therefore, does eating meat increase risk of cancer or does consuming unprocessed food such as fruits and vegetables protect against cancer? A study in South Africa suggests that the much higher colon cancer rates among white compared to black South Africans may be because of the amount of animal protein and fat they eat rather than a deficiency in fibre intake. What is clear, however, is that diets naturally high in fibre and low in animal foods can prevent colon cancer.

The effects of dieting on belly fat and skeletal muscle

Severe dieting, such as cutting down the amount of food you eat by half, has been shown to result in weight loss in the short term, but most of this loss is in the form of body water and muscle protein. Some fat is typically lost but keeping this fat off is harder than losing it in the first place. Of those who lose body fat, over 90% will put the fat back on within 5 years.
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There are also a number of unhealthy consequences that accompany severe dieting. The major problem is that cutting your daily calories in half for weeks or months will result in significant decreases in muscle mass. Skeletal muscle is very important for health and is one of the major tissues involved in fat burning; as mentioned, 1kg of muscle mass has the potential to burn up to an extra 3kg of fat per year. Other negative consequences that accompany severe dieting can include a reduced intake of essential minerals, vitamins and proteins, though these malnutrition aspects depend on the nature of the diet. Low-fat diets may also deprive individuals of healthy fats, such as the polyunsaturated or monounsaturated fats found in fish, olives, avocado and coconuts.