When performed incorrectly, even the best exercises can be ineffective and dangerous. Always consult a fitness professional if you are unsure of your form.
Squats are a popular exercise because they are effective at strengthening a wide range of muscles in a functional way. However, squats are also one of the most poorly executed exercises. When squatting, make sure your knees do not come over your toes, your back is straight and chest up and your thighs are parallel to the ground.
Another popular exercise that you usually spot people doing incorrectly is lunges. The common mistakes made while doing this exercise is leaning your torso too far forward, extending your knee over your toes and hyperextending your back leg, putting strain on that knee.
Dead lifts should always be performed with proper form otherwise they can lead to serious back injury. Avoid rounding your back and looking up and always maintain a tight core throughout.
When performing squats, your body should be parallel to the ground with your hips tucked in and core tight. Avoid raising or lowering your bum.