The most common myths about exercise

Sweating it out in the gym by doing those painful sit-ups for a six-pack? Well, it may not work out, say experts.

Among the many popular misconceptions about how to slim down or tone you body, Gillian Reeves, a fitness expert, has revealed some of the most common myths about exercise, reports the Daily Mail.

Myth: Sit-ups/crunches are the best way to a flat tummy

Reality: First off, lots of sit-ups or crunches alone won't tone a flabby belly. You need to combine any exercise with an overall weight-loss programme: eat a balanced diet and perform regular, varied exercise.

Sit-ups target the most superficial 'six-pack' core muscles, but too many of these will cause the tummy to bulge out, leading to a pot belly.

If you perform a dynamic movement such as a walking lunge, while rotating the top half of your body at the same time, you target all the abdominal muscles, as well as other large muscle groups that burn more calories and body fat. It is these kinds of moves that will help give you the tummy of your dreams.

Reality: You may be entertained, but doing this will ruin your posture, increasing the potential for injury and will also probably distract you from working as hard as you need to. Rather than reading, listen to some music or watch a television screen.

Reality: The weights area of a gym may be a little intimidating, but muscular strength and endurance are incredibly important for women too, to keep the bones and joints strong.

Use weights that you can easily lift 15 to 20 times before starting to feel exhausted -- this will tone and strengthen without building bulk.

Reality: If you run three times a week, your body will be fit for running. This does not mean you will be able to jump into any other activity.

Your cardiovascular system will be strong, but it is recommended that some kind of weight-bearing exercise is performed two to three times a week.

Reality: If you exercise hard for a long time, the body starts producing excessive amounts of stress hormones, including adrenaline and cortisol, which begin to break down muscle tissue. It is very important that after you exercise intensely, you rest your body for at least a day and eat well to aid recovery.

High-intensity exercise is good for heart health, but not effective for fat loss.

Reality: Stretching at the end of a workout session is beneficial as it returns the muscles to their pre-exercise dimensions. This prevents them from shortening over time.