The Measured Effects of Barbell Loading in a Flexed vs Neutral Lumbar Spinal Position: A Case Study

Abstract

This case study looks at the physical and psychosocial effects of the lumbar spine under high loads in a macro-flexion (65°) and relative-neutral (29°) position during an isometric 45° hip hinge for up to 25 seconds. A 150kg/330lb weighted barbell used by a powerlifter was taken through 1 set of macro-flexion and relative-neutral. Tightness, discomfort, and pain, as well as when the pain reached a 7/10 VAS were measured. The examiner documented a time stamp for each symptom once verbalized by the participant. For set 1, symptoms became present at 2 seconds (tightness), 5 seconds (discomfort), and 14 seconds (pain) with the set ending at 21 seconds due to 7/10 pain and extreme discomfort reported. There was then a 10-minute pause for the participant to recover and prepare for the next lift. For set 2, only one symptom became present at 20 seconds (tightness), with no discomfort and no pain. This study demonstrates that loaded flexion has the potential to provoke lumbar tissues at a greater rate than a loaded neutral position.