Target: lower back

Stand in a back extension machine facing the floor, with your heels hooked behind the retaining bar. Hold a weight plate across your chest. Keeping your shoulders back, bend at the hips and lower yourself downwards as far as is comfortable. Pause to control the weight, then lift yourself up again until your body is in a straight line from neck to ankles.

Expert tip: Adding resistance to this classic exercise will increase the
level of fatigue in your lower back muscles and encourage the growth
of new muscle tissue.