Whether you’re a beginner at lifting weights or an expert, checking your form is something that always needs to be done. Many people make common mistakes when lifting weights. These mistakes can lead to injury. Having correct form is one of the most important factors in proper weight lifting technique – in addition, it will increase the effectiveness of the exercise performed. Here are a few common exercises that people perform incorrectly:

1. Abdominal Crunches
Main Muscle Worked: Abdominal muscles
Mistake: Pulling your neck forward toward the chest. This puts strain on your neck muscles and uses accessory muscles. Many people also lift their glutes when going into their crunch. This takes the emphasis away from the abdominal muscles. Also, never hold your breath when going into the crunching motion.
Correction: Keep your hips and feet flat on the floor. Tuck in your belly button to help improve alignment of your lower back. Focus your eyes on the ceiling to help lift your chin toward the ceiling and not your chest. Lightly support your head with your fingertips rather than grabbing and pulling your head. Exhale while lifting into your crunch and maintain a continual breathing pattern throughout your repetitions.
 
2. Squats
Main Muscles Worked: Quads, glutes and hamstrings.
Mistake: Letting your knees go over their toes or arching your backs.
Correction: Keep your heels flat on the ground

3. Shoulder Press
Main Muscle Worked: Deltoid and trapezius
Mistake: Arching your back when pressing the weights over your head. One reason for this is using too heavy of a weight.
Correction: Keep your arms parallel with the rest of your body and make sure not to lock out your elbows at the top. Begin the exercise around ear level; press up and in with the dumbbells. To support your back, sit in a bench with back support. If you feel your back arching, try decreasing the weight. Another great substitute for dumbbells is arm bands. These come in varying widths that indicate the level of difficulty.