After doing a sprint interval workout , my running buddy complained that sprinting often made her low back feel tight. I had a notion that her psoas might be tight. This muscle is a major hip flexor and it attaches to the low spinal vertebrae. When the psoas gets short and tight from activities like sprinting, it can yank on the vertebrae,

creating a sensation of tightness. The good news is that stretching out the hip flexors can alleviate a lot of lower back pain. Once you are warm, and especially after a run or sprinting session, you should stretch your psoas. Learn two ways to stretch your psoas.

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Low Back Pain? Try Stretching Your Hip Flexors