Updated 30 September 2014

10 exercise myths busted

How hard should you push yourself? Does more sweat mean you burned more fat? A sports scientist addresses 10 of the most common exercise myths.

Have exercise misconceptions prevented you from starting an exercise programme? Professor Elmarie Terblanche (Chairperson of the Sport Science Department at Stellenbosch University) busts some of these myths and gives tips on how to improve your workout routine.

Myth #1:  I will burn more fat if I exercise longer at a lower intensity

So you’ve heard about the “fat burning zone”. In other words, if you want to lose weight, you need to exercise at a low intensity (a low heart rate). What few people realise is that you actually burn the highest proportion of fat while at rest (around 70 percent of your energy comes from fat) and by now we know that being a couch potato doesn’t make you thin. The most important focus in exercise and fat weight control is not the percentage of energy coming from fat during exercise, but the total energy cost of exercise, or how many calories are burned during the activity.

The faster you walk, step or run, for example, the more calories you use per minute. Therefore at low exercise intensity, you need to exercise for a very long time (far more than an hour per day) to match the total energy expenditure of a high intensity workout.

There is a growing body of research supporting the use of high-intensity interval training for fat loss. This form of “cardio” takes less than half the time (typically 12 to 20 minutes) of traditional long duration cardio and leads to better results, i.e. faster and greater fat loss, more rapid improvements in fitness and better exercise adherence.

Myth #2: Go hard or go home!

If this is your kind of thinking, you will never start or maintain an exercise programme. There is overwhelming evidence from research that one should rather do something than nothing, and that every little bit helps. For example, regular walking or gardening for as little as an hour a week has been shown to reduce the risk of heart disease. You will not necessarily be able to run a marathon or bench press 100 kg, but both your body and soul will be much happier.

Myth #3:  I can get my dream body if I just train hard enough

Both weight gain and loss is impacted by many factors, including dietary intake, your environment and genetics.  All individuals will not lose the same amount of weight on the same exercise program. Some individuals will actually respond very little to a regular exercise regimen in terms of losing fat weight (these individuals are called non-responders).  You have all seen runners finishing the Comrades marathon not looking the part. Now you will be mistaken if you think they have not trained hard and long hours to finish that race, because nobody can just step up to the starting line and run more than 90 km.

This is good evidence to show that exercise per se doesn’t make you thin, especially if you’re not endowed with the right genes. Losing body fat is a complicated matter (if not, we wouldn’t have rising obesity rates), and it goes far beyond a regular training programme. The good news, however, is that research has shown that being overweight and fit is much better than being thin and sedentary, as fitness is directly related to a lower risk of all-cause mortality. Furthermore, regular physical activity is one of the most important factors for successful long-term weight management.

Myth #4: Weight training makes women big and bulky

Weight training can make you bulk up - if you have the XY chromosome and it is your distinct intention to build huge muscles. Even then, it is no easy feat to gain muscle. It takes time and effort, a carefully compiled scientific training programme and finely tuned nutritional strategies. For women, however, these sound strategies will not be enough.

The reason being that women have nowhere near the required testosterone levels to put on any significant amounts of muscle mass. If you do see women with bulky muscles, you know for sure that their dietary habits include illegal substances such as anabolic steroids, growth hormone and many other designer drugs. There is just no other way. The truth is that strength training approximately two to four times a week, doing a variety of exercises for the major muscle groups, will help women to achieve a lean and toned appearance, and strengthen bones and joints. In fact, since women are more prone to osteoporosis, it could be said that women might actually benefit more from weight training than men.

Myth #5: I’m way too old for this

Age is just a very bad excuse. Studies have shown that it is never too late to start working out - you can reap benefits at any age. Exercise can help reduce the risk of bone and muscle diseases and help enhance daily functionality even later in life. This means you will be more independent as you get older, not to mention being admired by your grandchildren for completing the odd fun walk/run every now and then.

Myth # 6: Pass the puff pastry, I went to gym today!

You are in for a big surprise. You will probably gain weight, as the exercise will increase your metabolism and give you a healthy appetite. Research has shown that most people misjudge both the number of calories burned during exercise and the number of calories in food eaten. So never use exercise as an excuse to overindulge. If your goal is weight loss, you must learn to eat more without increasing your calorie intake. This means healthier choices of foods, smaller portion sizes and eating regularly during the day.
Myth #7: If you’re not drenched in sweat, you’re not working hard enough

The harder you work out, the more calories you'll burn within a given period and thus the more fat you stand to lose, but how much you sweat does not necessarily reflect how hard you're working. Some people tend to sweat bucket loads while others don't sweat much at all, regardless of their fitness level or degree of exertion. Your sweat rate is related to your body weight, your genetic makeup and external factors such as environmental conditions and clothing. Exercising in extremely hot weather or in a plastic "weight loss" suit will indeed make you sweat heavily and lose weight immediately. That lost weight however, is almost entirely water and the kilo’s will return when you replenish your fluids by drinking after the workout.

Myth #8: Sit-ups burn the boep

Not...a…chance. There's no such thing as spot reducing or burning fat off a particular body part, it is physiologically impossible. When you lose body fat, it comes off the body in a predetermined genetic pattern similar to how you gain the fat except in a reverse order. When your body is in fat burning mode, fat comes from all over the place—your arms, calves, thighs, abdominals, face, forearms, big toe, etc. If spot reducing really worked, people who chew gum would have skinny faces. Spot toning, on the other hand, does work, and resistance exercises will strengthen the targeted muscles. Look at the dominant arms of professional tennis players, and you’ll see the difference in their muscle tone and size. The best method for reducing overall body fat is the age-old tried and true combination of cardiovascular training, resistance training and limiting your calorie intake. Results come from doing these three things with persistence and consistence.

Myth #9: Morning workouts are better for your metabolism

Proponents of this piece of wisdom say that if your exercise in the morning, you jump-start your metabolism and therefore burn more calories during the day. There's absolutely no evidence that this is true. The best time to exercise is the time you want to do it, and are most likely to do it, whether it's morning, afternoon or evening.

The only exception is for those with high blood pressure.  Research has shown that your blood pressure remains low for up to 9 hours after an acute exercise bout. This phenomenon is called post-exercise hypotension. So for those with hypertension, exercise in the morning is advantageous, as it will keep your blood pressure low during the day when you need it most.

Myth #10: Electrolyte sports drinks will enhance your workout

This is another one of those myths that are costing the average person a lot of money.  Theoretically, sports drinks should be beneficial for those who exercise.  It contains sodium, which helps the body to retain water and keep you hydrated, and it contains sugar which your body burns for energy. However, contrary to what you may think, very few people exercise hard enough to sweat away significant amounts of sodium.

There is even some research that suggests consuming popular sports drinks during or after exercise does very little to add to sodium levels in the body. Furthermore, one has to train for more than two hours continuously before your carbohydrates stores in muscles will start to run low. Thus, for the average Joe, plain water is all you need.

- Adapted by Amy Froneman for Health24, from an article by Prof Elmarie Terblanche

Photo:  Fitness centre from Shutterstock


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