10 Fitness Myths
There are probably more myths about exercise and fitness than there were Greek gods. To help you separate fact from fiction, here's the honest truth about the 10 myths you're most likely to overhear in the locker room.
The myth: You can spot reduce fat
The truth: If you're unhappy with the amount of fat on your arms, thighs, stomach or anywhere else, you'll need to do more than exercise those areas if you want to start losing it. When you exercise an individual muscle, you do increase its size but you don't burn off the layer of fat that's covering it. The only sure way to reduce fat anywhere in the body is to increase your level of exercise (especially aerobic but also anaerobic) and to consume fewer calories, particularly from fatty foods.
The myth: Exercise can give you a heart attack
The truth: The risk is trivial, perhaps one in 500,000 to 1,000,000. For the vast majority of people, the far bigger risk to the heart is from a sedentary lifestyle.
The myth: The more exercise you do the better
The truth: Because something is good, it does not follow that more of the same is better. If the body isn't allowed time for rest and recovery, there will eventually be a breakdown in physiological functioning. In other words, the training becomes 'catabolic' rather than 'anabolic'.
The myth: To be beneficial, exercise must be exhausting
The truth: The 'no pain, no gain' approach is now as dated as an Arnold Schwarzenegger action movie. The vast majority of us will derive huge health and fitness benefits from aerobic exercise, which pushes our heart rate to no more than 75 per cent of its maximum for 20-30 minutes three times a week. (You can calculate your maximum simply by deducting your age from 220.)
The myth: The more you sweat, the better your workout
The truth: Steer well clear of keep-fitters who insist on wearing five layers of clothing, or even wrapping themselves in polythene bin-liners, to boost their sweating. All they're doing is losing more water and increasing their risk of dehydration. In fact, there's good evidence that the cooler your body temperature, the better your performance is likely to be.
The myth: Exercise boosts the immune system
The truth: This is actually partly true. Moderate exercise seems to enhance immune system functioning while intense exercise depletes it. Analysis by University of Toronto scientists of the effects of exercise on natural killer cell counts (a key immune system component) concluded that 'there could be a cumulative adverse effect' on the health of athletes who undertake 'prolonged and vigorous' exercise several times a week.
The myth: Muscle turns to fat when you stop exercising
The truth: It's biologically impossible - muscle and fat are separate and distinct tissues and cannot change from one to the other. The main reason why some people put on weight when they stop exercising is that they haven't also cut down on their calorie intake.
The myth: Exercise can help you shake off a cold
The truth: 50 people were infected with a common cold virus in a US study. 34 of them exercised aerobically at moderate intensity for 40 minutes, every other day, for 10 days. The remaining 16 were a non-exercise control group. The study concluded that exercising had no impact on the severity or duration of the volunteers' colds.
The myth: Low-intensity aerobic exercise burns more fat than high-intensity exercise
The truth: Your body does utilise a greater proportion of fat as fuel during low-intensity aerobic exercise than during high-intensity exercise. But the total amount of fat calories burned off during high-intensity exercise tends to be equal to, or greater than, the number used during low-intensity exercise. Because higher-intensity exercise has many other benefits - including for the heart - it's generally better to exercise at this level.
The myth: Sex impairs sporting performance
The truth: US research has shown that men's aerobic performance is unaffected 12 hours after sexual intercourse while a study led by Emmanuele Jannini of the University of L'Aquila has discovered that men's testosterone levels actually rise after sex, possibly making them more competitive and aggressive. Jannini believes the same may also be true of women.