If a powerlifter attempts a maximal deadlift with excessive lumbar flexion (rounding of the lower back), which failure mode becomes increasingly likely due to altered biomechanics?

💡 Explanation

Excessive lumbar flexion during a deadlift shifts the load anteriorly, increasing compressive and shear forces on the intervertebral discs. Because this concentrates stress on the posterior aspect of the disc, a posterior disc herniation at L4/L5 becomes more likely; therefore, it's the likely failure mode, rather than muscle strain or spinal activation.

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