You may have heard fitness instructors or trainers say "watch your form" when you working out with them or in a class, but what does that mean exactly and why does form matter? Physical form simply refers to the way your body is positioned when you are doing an activity. Good form works the body in the way you want it to. For example, good form will help you lift the appropriate weight in a safe way that is mechanically sound for the body without injury or strain. Bad form can quickly lead to injury and pain. Lifting too heavy a weight or moving weight through space in an unhealthy way can injure the back, joints, or connective tissues. Fitness experts know that quality of training is more important than quantity, and paying attention to each movement and repetition with correct form will teach your body healthy movement patterns over time. Next time you feel yourself rushing through an exercise or finding you are too tired to pay attention to your form, it means you need to slow down and re-assess your technique. At first, you may need to constantly remind yourself to correct your form during activity. Even if you are a seasoned lifter, assessing your form will lead to further improvement and should be a regular consideration.

The points of form to be aware of will change from activity to activity but there are some general ideas for most movement you can always rely on during physical activity.

Here is your body on good form:

Head and neck: Look straight ahead. Chin tucked instead of pointing out, neck is straight, head is not cocked to either side, tipped back or hanging forward.

Shoulders: Relax and pull back in space. Feel shoulder blades pulling towards each other and pressing down the back. This is called scapular retraction.

Spine: Maintain a soft, natural "S" shape while lengthening and stabilizing the body. Pretend that you have a string on the top of your head pulling you up as you feel your back lift and straighten. You may need to remind yourself to lift from the head and neck throughout your activities.

Arms, elbows and wrists: Be sure arms are relaxed and elbows or wrists are not extended in the wrong direction, putting undue stress on the joints. For example, when doing a bench press with a bar, be sure your wrists are not bending back towards your face in hyperextension, rather that they are straight up and down. When gripping any weight, do not squeeze tight with your hands and fingers. Keep your hands relaxed while maintaining a firm, safe grip.

Chest: Relax and breathe, don't hold your breath. Chest is neutral, not sinking with shoulders coming forward or puffing out causing the spine to sway forward.

Stomach and core: Abdominal muscles are engaged and pulled tight together. Be sure you are tightening the muscles, not sucking in air. Lifting the spine and tightening the abdominal muscles help protect the back from injury.

Pelvis and hips: Hips should be in a neutral position. Be sure to tuck your tailbone down as an extension of the spine. The top of the pelvis will tip slightly back, in line with the ribs when abdominal muscles are engaged.

Knees: Generally slightly bent, depending on the activity. Be sure not to overextend the knees or lock them back in hyperextension.

Ankles and feet: Weight should be balanced on toes and heels evenly. Be sure you are not rolling your ankles outward or inward and your feet are solidly on the floor with equal pressure over all surfaces.

Next time someone says to you "check your form," run through the following items: chin tucked, look straight ahead, eyes and face relaxed, shoulders down, abdominal muscles lifted, hips tucked under, knees not overextended, feet neutral (not rolling out or in), and lift up from the crown of the head. You may need to remind yourself of this head to toe checklist several times throughout your fitness routine and eventually, it will become more natural and automatic.