For most of us, heading into a gym can lead to confusion about what exercises to do.
If you want to change the shape of your body, can certain exercises really work?
The bone structure and proportions of adults are largely fixed. However, exercise can enhance our body shape and appearance, and increase muscle and bone strength.
We cannot physiologically change fat to muscle. But increased physical activity, exercise and good nutrition are key to losing fat.
Moderate to high-intensity cardiovascular training is very effective in reducing fat. This includes running and cycling.
Some women say, "I don't want to lift weights because I don't want to look muscular."
Bodybuilders will attest to the amount of work and overfeeding required for muscle growth. So the idea that weight training will make one bulky is a fallacy.
If you train specific muscles, these will increase in mass. If you do repetitive cardio exercise, only the large muscle groups you use to move will get stronger and increase in size.
So, running on a treadmill may make your bottom, hamstrings, quadriceps and calf muscles bigger, while using a cross trainer will work the same leg muscles and target the muscles in the chest, back and shoulders that push and pull. And doing compound exercises like squats or dead lifts will stimulate a larger number of muscle groups.
To look more athletic, train the shoulders so that they broaden, compared to the pelvis. This creates a more V-shaped body.
Weight-training exercises that work the deltoid muscles include shoulder presses and seated dumb- bell flies.
To have longer-looking, shapely legs, over-emphasise training the hamstring and bottom muscles, and de-emphasise training the quads and adductor groups.
Examples of exercises that shape the thighs are hamstring curls (bringing the heels to the bottom by bending the knees) and stiff- legged barbell dead lifts (bending at the hip to lower weights down the front of the legs).
Inclined chest presses and pec flies will emphasise the upper chest muscles.
Training the back and abdominal muscles is important to support the natural curves of the spine, improving posture and body shape.
A simple, effective exercise is lying rotations. Lie face up, bend the hips and knees to 90 degrees, and keep the knees together. With arms outstretched to 90 degrees, slowly allow the knees to rotate towards one of the hands, then stop just before reaching the hand and repeat on the other side.
Stretching will prevent unwanted loss of range of motion in joints due to muscle tightness. Yoga, pilates and general stretching are great at keeping us lithe and supple.
Yoga, pilates and martial arts nurture the practice of movement patterns through each joint's range of motion.
If efficiency of movement is a pleasure to the eye, then there is much to be said about developing grace in order to enhance aesthetic beauty.
•Julie Netto is an occupational therapist at Curtin University.
•This article first appeared in The Conversation (http://theconversation.com), a website which carries analysis by academics and researchers.