Proper form is especially important when you are performing lifts with lots weight. Examples of heavy lifts include deadlifts, bench press, the clean and press, clean, squats, front squats, and split jerks.
Start by firmly positioning yourself in the starting position of the lift whether it be lying underneath the bar (bench press), with the bar on the front of your shoulders (front squat and split jerk), with the bar resting on the back of your shoulders (squat), or with the bar on the floor in front of you (deadlift and clean and press). Make sure your feet are shoulder-width apart with your toes angled out no more than 15 degrees.
Next, firmly grip the bar (with front squats and split jerks, place the bar so it rests firmly on the front of your shoulders with your elbows up and triceps parallel to the floor).
Next, engage your core by flexing your stomach muscles to 20% of their maximum capacity (like what you would do if you were preparing for someone to lightly slap you in the stomach).
Do not draw your breath in to the top of your lungs but sucking in your stomach. This will round out the lower portion of your back, concentrate a disproportionate amount of stress, and might cause injury.
Then, for deadlifts, bench press, and clean and press, grip the bar almost as hard as you can. With your grip strong, activate (which is another word for slightly tense) all the other muscles of your body starting with your feet. Grip the floor with your feet by slightly turning them a few degrees toward each other. Then activate the rest of your muscle groups in sequential order from your feet to your head from the bottom to top.
Next, draw your breath into the bottom of your lungs by pushing your stomach out as your breath comes in. Once you have drawn your breath in, hold it. This should create a zone of pressure in your abdomen. Doing this increases your stability, engages your core, and provides support for your spine. It’s known as the Valsalva maneuver. Do NOT bring your breath into the top of your lungs by sucking in your stomach and raising your chest. This will round out the bottom of your spine and might result in injury.
Perform the first half of the lift in a smooth, controlled motion. After you complete the first part of the lift, exhale and complete the second part of the lift in a smooth, controlled motion.