Introduction: The most prevalent spinal column abnormality occurs in girls due to the musculoskeletal weakness and results in postural problems. This study aims to investigate the effect of eight weeks exercises of the National Academy of Sports Medicine (NASM) on the lumbar curvature of the female students.
Methodology: In this Quasi‐Experimental method more than 500 female students between 12 -15 years of schools in Behbahan as a prototype sampling method selected (checkerboard pattern)and screened respectively. The required information by flexible ruler (measuring lumbar lordosis), one repetition maximum test (measuring back muscles strength), range of motion (Schober transformed test ) were measured. At the end of 22 students who had an angle of curvature of less than 20, were selected and randomly divided into two groups such as NASM exercises (age 14.1±5.13 years, height 33.8±09.158 m, weight 43.7±55.55 kg) and control group (age 74.1±9.13 years, height 74.6±91.155 meters, weight 09±00.54 kg). The experimental group participated for 8 weeks, 3 sessions of 60 minutes in the exercises. Data analysis was performed using ANCOVA.
Results: The results showed a significant relationship between lumbar lordosis (P=0.000, F=166.9), strength of trunk muscles (P=0.000, F=6.333), and range of motion of the trunk (P=0.000, F=31.12) of the students before and after training course in the experimental group and the control group (P = 0.05).
Discussion: NASM exercise may be considered as an efficient method for increasing the lumbar lordosis, improving the strength of the back muscles, range of the trunk motion of the students with Straight Back Syndrome and prevent the problems in aging.