Hello: "There should be a punch between the waist and the bench" is a high-risk action, which is widely used by bodybuilders and fitness coaches and is not suitable for ordinary trainers. Although this will stimulate the chest muscles more, I suggest you not to do so. You can try the "micro-bow" waist posture, or you can refer to the following bench press standard movements completely.

Recommended standard:

Determine the target muscles: pectoralis major, deltoid (toe) and triceps brachii.

Determine the direction of resistance: the horizontal plane is vertical downward.

Determine the position of the body: lie on your back. Head, shoulders, back and hips touch the bench, and feet touch the ground. The grip distance between hands is that when the arms are down to the elbows and the back plane is flat, the forearm is at right angles to the upper arm. Hold the barbell in your palm.

Keep your body stable: always keep the position of your head, shoulders, back, lower back, hips and feet. The scapula has been contracting and the abdomen remains tight.

Determine the action route: the route of elbow joint and barbell does not deviate from the horizontal plane, and the movement plane of barbell is on the same plane as the lower edge of chest.

Determine the range of motion: the elbow joint at the apex of centripetal contraction is not completely straight, and the scapula does not move forward obviously. The elbow joint does not exceed the back of the body during centrifugal contraction.