Abstract
This 2022 pilot study by Reyes-Ferrada et al. investigated trunk strength ratios and muscle quality in 27 healthy males. The study found that trunk extensors are significantly stronger than flexors, with a conventional ratio of approx. 0.41-0.44. While this ratio remains stable across speeds, functional ratios (eccentric vs. concentric) vary significantly with velocity.
The findings suggest that functional strength ratios provide a more dynamic and accurate picture of trunk stability than conventional measures. Clinicians should consider movement velocity when assessing muscle quality and core balance in athletes.