No abstract

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.

Males had higher lateral torso endurance than females. Adolescents in general demonstrate their peak lifetime endurance as they appear more endurable than children and comparable adult groups. These data of endurance times, their ratios and percentiles in healthy normal subjects form a database bridging existing data for children and adults that may be useful for guiding training and rehabilitation.

Poor low back muscle endurance has been shown to be a predictor of chronic low back pain. While posture is a modulator of low back muscle endurance, it is unclear whether the phenomenon is neural or mechanical. This study examined low back muscle endurance with changing head and neck posture in a sample of 117 children using the Biering-Sørensen test. Each subject performed the test in a neutral posture followed by randomly selected flexed and extended head and neck positions. Head posture was found to significantly influence low back muscle endurance within subjects (p < .001), with extension yielding the highest endurance scores (boys = 186.6 ± 66.2 s; girls = 192.1 ± 59 s), followed by a neutral posture (boys = 171.3 ± 56.5 s; girls = 181.7 ± 57.3 s), and flexion (boys = 146.2 ± 63.8 s; girls = 159.8 ± 49.3 s). Given the minimal influence of changing moment from head and neck posture, it appears other mechanisms influence endurance score.

The aim of this study was to investigate whether torso endurance scores were linked with anthropometric variables in children and to develop a normative scale of anthropometric measures in children in both genders for clinical assessment, rehabilitation, physical education targets and young athletic training purposes. It was hypothesized that changes in anthropometric measures through ages 7 to 14 influence endurance scores in both subsets. It was also hypothesized that boys and girls differ in the relationships between torso muscle endurance and anthropometric measures. Reduced torso muscle endurance has been identified as a potential personal risk factor for developing low back pain and decreased athletic performance. However, torso muscle endurance data in children is lacking. Further, given that endurance tests require postures where the body is supported horizontally, it makes sense that anthropometric variables would influence endurance. Isometric torso muscle endurance scores established through four tests were performed in random order by healthy children. These were correlated with anthropometric dimensions. Seven hundred and fifty-three children from one elementary school (394 boys and 359 girls) were grouped into 8 age strata (7 to 14). Each age stratum had different number of participants for boys and girls. Four tests established isometric torso muscle endurance: Biering-Sorensen test for extensor endurance, flexor endurance test and right and left side bridge tests. The mean, standard deviation of the endurance tests and anthropometric measures were determined for each gender/age strata. The Pearson product-moment correlation coefficients were determined between the anthropometric dimensions and isometric torso endurance scores for each gender/age strata. Variance in endurance scores were not well explained by anthropometric measures. Variables other than segment length and circumference influence torso endurance as children grow and develop. Given links to future back pain and athletic performance, more investigation would be justified.