Osteoporosis is a common condition among postmenopausal women, characterized by weakened bones and an increased risk of fractures, especially in the spine. As exercise is often prescribed to enhance bone strength and improve overall health, it’s important to understand which types of movements are beneficial and which might actually pose risks. A study conducted by Dr. Mehrsheed Sinai and Dr. Beth Mikkelsen at the Mayo Clinic has provided valuable insights into the impact of specific exercises on women with postmenopausal spinal osteoporosis.

The Study: Flexion vs. Extension

The study involved 59 women with postmenopausal spinal osteoporosis, all experiencing back pain. These women were divided into four groups based on their prescribed exercise regimen:

• Group E: 25 women performed extension exercises.
• Group F: 9 women performed flexion exercises.
• Group E+F: 19 women performed a combination of both flexion and extension exercises.
• Group N: 6 women performed no exercises (control group).

The participants were between 49 and 60 years old, with an average age of 56. Follow-up evaluations occurred between one and six years after the program began, during which the women underwent spinal x-rays to assess any new vertebral compression fractures or further wedging of the spine.

Results: The Risks of Flexion Exercises

The results were striking. The study found that women in the flexion-only group (F) had the highest incidence of new fractures—89% of participants in this group experienced further spinal fractures during the follow-up period. By comparison, only 16% of the women in the extension-only group (E) suffered fractures, demonstrating a significant difference.

For those performing a combination of flexion and extension exercises (E+F), the fracture rate was also high at 53%. Meanwhile, women in the no-exercise group (N), who received no specific intervention, experienced a 67% fracture rate, which was still lower than the flexion group but much higher than the extension-only group.

Interpretation: Why Flexion Exercises May Increase Fracture Risk

Flexion exercises involve bending the spine forward, which can place significant pressure on the front portion of the vertebral bodies, increasing the risk of compression fractures in osteoporotic bones. In contrast, extension exercises, which involve arching or extending the spine backward, appear to place less strain on vulnerable areas of the spine and may even help strengthen the supporting muscles of the back.

The study suggests that flexion movements, such as crunches or forward bends, may exacerbate the risk of fractures in women with osteoporosis. This is especially important when working with postmenopausal women, who often experience loss of bone mass, particularly in the spine, due to decreased estrogen levels.

Implications for Pilates and Other Exercise Programs

For Pilates instructors, physical therapists, fitness professionals and exercise physiologists working with postmenopausal women, this study provides critical guidance on exercise selection. While movement is key to maintaining bone density and overall health, extension exercises or isometric exercises that promote stability without excessive flexion of the spine should be prioritized.

Here are a few Pilates-based exercises that align with these findings and are safe for clients with osteoporosis:

• Prone Single Leg Lifts: This exercise focuses on extending the hips and strengthening the muscles of the glutes and hamstrings - use a pillow under the abdomin to protect the ribs.
• Rising Swan: Another extension-based movement that helps to strengthen the posterior chain while avoiding spinal flexion - use a pillow under the abdomin to protect the ribs.
• Modified Side Plank: This isometric exercise enhances core strength without placing undue strain on the spine.
• Straight back in the abdominal series on the Reformer or the Ladder Barrel: This can be beneficial if taught correctly with no spinal flexion and focus on elongation rather than forward rounding, keeping the spine neutral and moving at the hip joints only.

Avoid exercises that emphasize spinal flexion, such as traditional roll-ups, sit-ups, or certain stretches that round the spine forward, as these movements can contribute to vertebral compression and increase fracture risk.

Conclusion

This study reinforces the need for thoughtful exercise selection in women with postmenopausal osteoporosis. Extension exercises are far more beneficial and protective for the spine compared to flexion-based movements, which can increase the likelihood of vertebral fractures. As Pilates instructors and fitness professionals, it’s essential to modify programs to ensure the safety and effectiveness of exercise routines for individuals with osteoporosis. By focusing on safe movement patterns, we can help our clients maintain their strength, mobility, and quality of life while minimising the risk of injury.

If you are interested in learning more about Osteoporosis and Osteopenia please check out my Pilates for Osteoporosis and Osteopenia course here.