Part 3 in a series

Myth 5

Weight training makes women’s muscles big and bulky. One of the most common concerns that women used to have is that if they lift weights, they will build large muscles and lose their slender, feminine looks.

These days they are more eager to weight train because they know there are benefits to be had from lifting weights in building denser, stronger bones and helping to burn off extra calories by raising their metabolism.

But there is still a perception that weight training will build muscle size. There is a common notion that there are two distinct methods of weight training: one method for size and strength (by lifting heavy weights) and another method for creating lean, slender and “toned” muscles (by lifting lighter weights).

The truth of the matter is that both these notions are myths.

Women naturally produce much, much less testosterone than men do, and testosterone is the hormone that is primarily responsible for gaining muscle size. It is very difficult for women gain appreciable amounts of muscle size by weight training, through it has been well supported in research that there are increases in other physical measures, including bone density, tendon and muscle strength and density.

But, the image that often comes to mind is that of female bodybuilders, most of whom use anabolic steroids (synthetic testosterone) and work out very hard on elaborate programs lifting very heavy weights in order to achieve that high degree of muscularity.

Some women want to perform light, high-repetition exercises in order to “tone” their muscles without increasing their size.

The word “tone” in this sense is misleading. Muscle tone correctly refers to the constant, low-frequency contractions that occur in all muscles – it is commonly thought of as the firmness of muscles at rest. But you can also increase “muscle tone” by increasing size and strength, so the word “toning” doesn’t define any difference between strength training (heavier) and endurance training (lighter).

If done properly, women can benefit from strength training without increasing size.

Myth 4

Drink at least eight glasses of water a day to help you lose weight. Surprisingly, no scientific evidence can be found that supports the idea that we are vastly underhydrated and we need to drink close to two litres of water a day, or that drinking water reduces hunger and helps people lose weight.

Recent research, including a 2002 study published by nephrologist Dr. Heinz Valtrin in the American Journal of Physiology, showed that we may even be drinking more than we need. The only thing that drinking vast quantities of liquid would do is keep you busy running back and forth to the bathroom and spend less time eating or thinking of food.

We evolved getting our calories from food, so the body has two separate mechanisms to drive hunger and thirst. And water is absorbed through your GI tract so quickly that it doesn’t contribute to a full feeling. However, water lost from sweat must be replaced or mental alertness and physical performance can suffer if these losses exceed about two per cent of body weight. The fact is that water requirements vary with gender, age, diet and metabolism – some people need more and some less, so drink when you are thirsty. And remember that you get a modest portion (about 20 per cent) of you daily water absorbed through food eaten.

Kerry Senchyna holds a bachelor of science degree in kinesiology and is owner of West Coast Kinesiology.