The prevailing view today is that cancer is a “genetic disease” involving nuclear mutations in oncogenes and tumor suppressor genes. Although this somatic mutation theory is currently the dominant theory for the origin of cancer, the mitochondrial metabolic theory is emerging as an alternative explanation for the origin of cancer.

Extension work on the GHD can be both similar and dissimilar in action to CrossFit’s nine foundational movements. The GHD hip extension is similar because the spine is held in neutral throughout each rep. Both the GHD back extension and the GHD hip and back extension require deliberate flexion and extension of the spine. While the spine is always held rigid when lifting, training flexion and extension on the GHD builds strength, positional awareness and coordination that can be applied to other movements.