Research
Cellular
Concerns exist regarding the performance of dynamic spinal flexion exercises, such as the crunch, due to the belief that the spine has a finite number of bending cycles.
Fitness professionals should consider the potential risks associated with dynamic spinal flexion exercises in program design.
StrongQualifiesmedium confidence
Concerns are usually predicated on the belief that the spine has a finite number of bending cycles and that exceeding this limit will hasten the onset of vertebral degeneration.
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The abstract indicates a review of existing research.
Source
To Crunch or Not to Crunch: An Evidence-Based Examination of Spinal Flexion Exercises, Their Potential Risks, and Their Applicability to Program Design
Bret Contreras et al. · Strength and conditioning journal · 2011
DOI 10.1519/ssc.0b013e3182259d05
reviewCited 21×
Read the paper DOI resolved against Crossref · corpus check 2026-06-10
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