With more and more research, news stories and social media there is a vast amount of information about exercise, weight loss, diet, strength training and overall health.
Today we are busting the some of the top health 'myths' that we hear most commonly in our clinic. It is easy to get caught up in the hype of the latest fitness craze or diet but it is important to remember to investigate where the information is coming from and remember that everybody is different. What works you’re your friends, other gym goers or even your mum may not be appropriate for you. So, let’s clear up some of the most common health and diet myths.
1. BMI is a good assessment of your current health and future health risks?
2. Cardiovascular style and low intensity exercise is best for weight loss
3. Cutting carbs will help me lose weight faster
4. I am cutting fruit out of my diet because it is high in sugar
5. Doing ab exercises will help me loose belly fat
1: BMI is a good assessment of your current health and future health risks:
The BMI or body mass index was first devised by a Belgian astronomer, mathematician, statistician and sociologist in 1830 (Eknoyan, 2008) . The modern version and the one we know and use today was first published in the Journal of Chronic disease in July 1972 by Ancel Keys (Keys, Karvonen, Kimura, & Taylor,
1972) . This was a simple tool for medical professionals, the government and even insurance companies to classify 'risk'. However, this simple tool only considers height and weight, to classify individuals. Many athletes and body builders have already experienced being classified as 'overweight' even 'obese' due to
the simplicity of the formula. Muscle is a denser material than body fat which will place a greater pressure on the scales. This may lead to the individual to displaying a higher body weight, thus increasing the BMI. This means the formulae is flawed and not a great measurement of overall health and risk. Your health professional should use a range of assessments, including body densitometry to determine percentages of fat free mass and fat mass of the body, waist circumference and other health measures. As we now have better tools to asses’ health and wellbeing the BMI should be used in conjunction with other measures to assess overall health and risk. Ask your health professional to assist you with taking these other measures.
2. Cardiovascular style and low intensity exercise is the BEST for weight loss:
Any exercise is good for the human body, unfortunately there is no one best method specifically for weight loss. It was thought that at low intensity and long duration exercise is the best to 'burn' fat. It is true that to 'burn' fat we need to presence of oxygen, which will usually only happens after we are exercising for at least 2 minutes. So, it is somewhat true that low intensity exercise will ‘burn’ fat.
However, a low intensity is not enough to 'stress' the body and will therefore result in little no adaptations or change over time. A combination of weight training (to build muscle mass- which is metabolically active- which 'burns' more calories) and cardiovascular style exercise both high and medium intensity will aid in weight loss. It is recommended by the American collage of sports medicine that at least 300 minutes of exercise per week is needed to achieve with loss. The ‘burning’ of fat
molecules occurs when the bonds that hold these molecule together are broken and energy is released. This breaking of the bond only occurs when oxygen is present, fat molecules provide approximately 140 ATP (the energy currency in the body) in comparison to glucose or sugar which provides 36 ATP when the bonds are broken.
3. Cutting Carbohydrates will help me to lose weight faster:
Carbohydrates (CHO) are essential fuel for the body and more importantly they are the best type and the optimal fuel type for your brain. There are two categories of carbohydrates- simple(refined) and complex. Simple CHO provide quick energy and complex provide long lasting energy. When we eat CHO, the body breaks it down into its simplest form, glucose or sugar. With complex CHO this process takes
longer and the energy release is slower. So reducing the amount of simple CHO in your diet is a good start to weight loss. The body can store glucose in the muscles and liver, but only so much. When these storage sites are full the body stores the glucose in the adipocytes (fat cells), which the body has infinite storage capacity. Therefore if we are consuming too many calories, which are not used for essential
bodily function, movement or exercise the body will store the energy for later. A careful balance of exercise and nutrient rich foods will help you to manage your weight. Be sure to fuel your brain with complex CHO.
4. I am cutting fruit out of my diet because it is high in sugar:
It is a common misconception that fruit is high in sugar. While fruit does contain a high level of fructose, a naturally occurring sugar, the essential fiber in fruit slows the rate of absorption in the digestive system. Therefore this only slowly releases the sugar, resulting in a consistent blood sugar level, rather than a spike. Fibre is essential for gut health, this type of fibre is prebiotic and helps to feed your gut
bacteria, which helps to keep your gut healthy. Fruits also contain important sources of minerals and vitamins. Mineral and vitamin sources from fruit include potassium and magnesium; important for heart health and repair of muscles, folate; important for cell growth, and vitamin C which increases the absorption of iron. Including fruit in your diet will reduce the risk of some cancers and keep your gut
healthy. If you need a sugar hit in the afternoon fruit is your best option. To ensure you achieve two serves of fruit per day, keep two serves of fruit on your desk and consume one in the morning and the other in the afternoon to enforce the routine. One serve of fruit is a medium apple or banana. Occasionally you might also like to add some dried fruit (30g is one serve).
5. Doing abdominal exercise will help you get a flat stomach:
Everyone has a 'six pack'. Our skeleton or bone structure is heavy and without our muscles we would simply fall over. Everyone has a 'six pack' to keep the upright, it may not be visible or seem as though it is particularly strong or 'insta worthy' but we all have one. There is no magical exercise that will help us get one either. In fact you can increase your abdominal strength when you do any type of resistance
exercise by 'bracing'. By simply tensing or holding on our abdominals we will activate the muscles and over time it will get stronger. Including a set of exercises to train all the muscles of the core is important. The muscles of the core are made up of four muscles, the rectus abdominus, the internal and external oblique’s and the transverse abdominus. Despite our best efforts in the gym, the human body
unfortunately likes to store fat around our abdomen to 'protect' our organs. Due to this biological drive it can sometimes be very hard to decrease this fat.
Eknoyan, G. (2008). Adolphe Quetelet (1796-1874)-- the average man and indicies of obesity. Journal of Nephrology, Dialysis, Transplantation, 47-51.
Keys, A., Karvonen, N., Kimura, N., & Taylor, H. L. (1972). Indicies of relative weight and obesity. Journal of Chronic Disease.