Does Spine Posture Affect Isometric Torso Muscle Endurance Profiles in Adolescent Children?

The purpose of this cross-sectional study was to examine mean values of isometric torso muscle profiles of four spinal postures (good posture, thoracic kyphosis, lumbar lordosis and scoliosis) among 743 children from the ages of 7 to 14 years old. It was hypothesized that having good posture, thoracic hyper-kyphosis, lumbar hyper-lordosis and scoliosis is linked to different isometric torso muscle endurance profiles. Torso muscle endurance, established through four tests (Biering-Sørensen Test for extensor endurance, Flexor Endurance Test and right and left Side Bridge Tests for lateral endurance) performed in random order and spine postural screening categorized subjectively by observation was measured. Posture was proved to be linked to endurance scores. Hyper-lordotic spines demonstrated a decreased endurance compared to the three other postures (F = 5.344; p < 0.01); pairwise comparisons confirmed these differences (p < 0.05). Trends further suggested that hyper-lordosis was detrimental in lateral chain torso endurance while a hyper-kyphotic spine was more resilient in anterior chain torso endurance. Understanding the relationship between posture and endurance may be beneficial in clinical, as well as coaching/teaching settings.