Joanna Hall - The GI Walking Diet - Lose 10lbs and Look 10 Years Younger in 6 Weeks

We all tend to have different VO 2MAX values. Athletes have very high values, meaning that their bodies are better able to take in oxygen and use it to produce energy. Normal people have more average levels. With age, however, nature takes its toll on all of us and we all experience a decrease in our VO 2MAX.

What This Means to You

A lowering in your VO 2MAX can cause a decrease in your performance, your everyday ‘huff and puff’. Physical tasks that seemed easy now require a little more effort. You may feel out of breath and that you don’t have enough energy. But it doesn’t have to be like this …

What You Can Do

At any age, if you exercise vigorously and keep lean you can have a much higher VO 2MAX. Research has shown that athletes aged from 65 to 75 can have the VO 2MAX of young sedentary adults and are capable of performing at levels once thought physically unattainable.

But we do have to be realistic. Even among older athletes who exercise vigorously throughout their lives, VO 2MAX will still eventually decline. The important point, however, is that the rate of decline will be much slower. A US study examining former elite long-distance runners over a 22-year period found that regardless of how much they trained, all did eventually lose aerobic fitness; but (and this is a big BUT) the rate of decline may be lessened for up to 20 years if an individual takes regular vigorous endurance exercise.

Action Worth Investing In

You’ll find that the six-week walking plan can have a significant impact on your cardiovascular fitness. It will give you more huff and puff and loads more energy. If you combine it with the six-week menu plan, you’ll lose 5–10 per cent of your excess weight. Your clothes will fit better and you will look younger.

For women, oestrogen plays a significant role in controlling calcium absorption and retention in the bones, so when it starts to decline it can have a big impact on the body.

What This Means to You

Without adequate oestrogen, women over the age of 50 are at increased risk of osteoporosis, stress fractures or broken bones. In addition, research is showing how calcium has a vital role in helping the body burn fat. The exact mechanism is not entirely understood but studies have shown that when people consume inadequate amounts of calcium, the body stores more fat, resulting in weight gain. But it doesn’t have to be like this …

What You Can Do

Most experts say that calcium should come from the diet. (For details of good dietary calcium sources.) Resistance training is an excellent way for women of all ages to stimulate and maintain bone growth. Hormone replacement therapy, although once considered promising, now appears to have little or no positive effect on bone mass growth.

Action Worth Investing In

Following the six-week menu plan will help boost your calcium intake, while just by completing the six-week strength plan twice a week, you’ll experience big improvements in your physical capacity, body tone and strength.

Many hormones play a significant role in the body. As we age, hormonal changes can affect us in many ways. You will come across a number of them in this book – here is an overview of the most important ones.

Human growth hormone:secreted in much greater amounts in youth to help bones grow. Also helps the body to metabolize fats. Levels tend to diminish with age, which is thought to contribute to decreases in cell membrane composition.

Progesterone:the gestational hormone, which prepares the lining of the uterus for the fertilized egg and maintains pregnancy. Progesterone is a ‘precursor’ hormone, which can be converted by the body into other steroid hormones. As levels fall, an imbalance occurs between this hormone and the other primary female sex hormone, oestrogen. This is linked with weight gain, decreases in bone density and a possible reduction in sex drive.

Testosterone:the male sex hormone, most commonly known for promoting libido and stimulating sperm production. Also helps protein build muscles, skin and bone, and nourishes all the tissues of the male urinary and reproductive systems. Regulates the production of prostaglandin, which seems to keep prostate growth under control. In both sexes, testosterone levels decrease with age. This has a significant impact on health and wellbeing, contributing to decreases in bone and muscle development as well as reduced virility. Recent evidence has linked low testosterone with Alzheimer’s disease.

DHEA:dubbed the ‘mother of all hormones’ because the body uses it to produce a number of hormones including testosterone, oestrogen and progesterone. DHEA production drops sharply after the age of 25; by the age of 75 we are producing only 10–20 per cent of the DHEA our bodies manufactured at 20, and this has an impact on the other sex hormones.

Thyroid hormones:regulate the body’s metabolism, temperature and heart rate. If the thyroid isn’t functioning at its optimal level, neither are you. Thyroid deficiency is not specifically age-related as woman can be prone to it at all ages, especially during and after pregnancy.

Insulin:the main hormone for promoting the transport of glucose rather than fat into muscle cells to be used as energy; also a potent inhibitor of the fat-stimulating hormone HSL. Excess body fat is associated with insulin resistance. Some researchers have suggested that reducing body fat through calorie restriction without under-nutrition may help improve the insulin response, which can reduce risk factors for disease. You can enhance your insulin sensitivity by increasing your intake of the healthy omega-3 fatty acids found in oily fish such as salmon, mackerel and fresh tuna, and in walnuts, flaxseeds and soya products. Vigorous exercise can also improve insulin sensitivity.

Epinephrine and cortisol:prepare the body for an instant state of readiness – the classic ‘fight or flight’ response. Epinephrine is the primary hormone that stimulates lipolysis, the breakdown of fat. Epinephrine binds to the receptors on various cells and can either activate or inhibit HSL, the hormone responsible for fat mobilization. Epinephrine excretion appears not to change with age. Cortisol releases glucose and fatty acids into the bloodstream to provide energy to the muscles. It also has a direct impact on the body’s blood sugar levels. If too little cortisol is released, hypoglycaemia (low blood sugar) can develop; if too much cortisol is released, hyperglycaemia (high blood sugar) can develop, which can increase the risk of developing diabetes. When people experience prolonged stress, cortisol levels remain elevated for long periods, and recent research shows that this can lead to weight gain, especially on the belly. Cortisol excretion appears to increase with age.