As a review from the post, Low Back Pain During Running: Tips For Ultramarathon Runners Pt. 1, low back pain can arise from:

  • Tight hip flexors that fail to allow full hip extension, causing lumbar stress;
  • Poor core stability, where the lumbar spine and pelvis fail to stay stable as the hip pushes off;
  • Being too upright in the stride, resulting in compensatory extension from the low back; and/or
  • Excessive trunk rotation due to an inefficient arm swing.

Low Back Pain Prevention: Exercises and Form Cues

Low Back Pain During Running: Tips For Ultramarathon Runners Pt. 2Stretch The Hips!
The hip flexors must be flexible enough to allow hip extension equal to the trunk. A simple test of this involves lying on the edge of a table or bed and hugging one thigh tightly to the chest. The opposite upper leg should be able to remain fully level with the table, with the lower leg hanging close to 90 degrees.

This test, itself, is a stretch: passively hanging, or actively ‘pulling’ the leg toward the table and floor. This can be done for 30 to 60 seconds, for several reps, to improve hip-flexor mobility.

A great ‘on-the-go’ stretch, pre- and post-run, is what I call the ‘Split Hip Stretch.’ It involves putting a foot up on a step, bench, or any object two to three feet high. The flexed leg should rest against the chest (with the knee behind to toes). The trailing leg is getting stretched by being slightly wide and fully extended. The stretch is created by actively squeezing the trailing leg’s glutes and quad muscles. This exercise creates a combined flexion, extension, and abduction stretch for both hips, all the while protecting the low back from extension stress. Hold for 20 to 30 seconds, for several reps, each side.

Trunk-Stability and Hip-Mobility Exercises
Practice trunk stability while extending the hips using these exercises:

  • All Fours Bent Knee Leg Extension
    This exercise practices the ability to extend the hip on a stable trunk. Extend the bent-knee leg upward, careful to keep the low back and pelvis stable. The goal is to extend the thigh to the level of the trunk. However, only go as high as you can go without over-arching through the low back. Hold three seconds or a single exhale. Alternate, 10 repetitions per side.
  • Straight Leg Extension Plus Opposite Elbow
    This exercises adds an opposite-elbow extension, working on arm coordination along with hip extension and trunk stability. Extend the leg and opposite arm simultaneously. Hold three seconds or a single exhale. Do 10 repetitions in a row, per side.
  • Plank Plus Leg Extension
    This is an advanced strength exercise, combining an elbow plank with a straight-leg-extension lift. Emphasis is on keeping the low back and pelvis stable, while the hip moves to a level equal to or just slightly higher than the level of the trunk. Hold each extension three seconds or a single exhale. Alternate, 10 to 20 total repetitions.

Source:; Joe Uhan; November 11, 2014.