Jefferson Curl

The Jefferson curl is a slow, controlled spinal-flexion mobility drill done standing on a low box while holding a light barbell or dumbbell, rounding the spine forward one vertebra at a time with the legs nearly straight, then reversing back up the same way. It builds controlled strength through spinal flexion under a light load rather than heavy loading like a conventional deadlift, so the weight should stay modest throughout.

1. Stand on a low box holding a light barbell in front of your thighs
2. Tuck your chin and round your spine forward one vertebra at a time until fully curled
3. Reverse the movement slowly, stacking each vertebra back up from the bottom

• Using too much weight, turning the slow curl into an uncontrolled fold
• Bending the knees significantly instead of keeping the stretch in the spine and hamstrings

• Seated version on a bench for a shorter range of motion
• Bodyweight-only version reaching toward the floor for beginners