The Changes in the Center of Pressure and the Time to Stabilization in Male Football Players With and Without Hyperlordosis During a Single-leg Jump-Landing Task

Hyperlordosis is one of the deformities in the lumbar spine, which causes changes in the forward center of gravity and increases the movement of the pelvis. It also changes the stability of the trunk, lumbo-pelvic-hip core complex, and lower limbs. This study aims to compare the changes in the center of pressure (COP) and the time to stabilization (TTS) in male football players with and without hyperlordosis during a single-leg jump-landing task.

 This is a causal-comparative study with a cross-sectional design, conducted on 28 male football players (14 with hyperlordosis and 14 without hyperlordosis), with a mean age of 24±2.42 years, a mean height of 178±6.06 cm and a mean weight of 72±4.93 kg. First, the Sargent jump test was taken to determine their maximum vertical jump. Then, they were asked to jump with two legs and a half maximum vertical jumping height and land on the force plate with the dominant leg. The independent t-test analysis was used to analyze the data in SPSS software, version 23.

 A significant difference in the COP fluctuations in the mediolateral (ML) direction (P=0.015), the maximum and minimum COP displacements in the ML direction (P=0.021, P=0.001), the TTS in the ML direction, and the total TTS (P=0.001), was observed between two groups, but no significant difference was found in the amount of COP variability in the anterior-posterior (AP) and ML directions, the amount of COP fluctuations in the AP direction, the minimum and maximum COP displacements in the AP direction, and the TTS in the AP and vertical directions (P>0.05).

 It seems that changes in the sagittal plane in the area of the lumbar spine and pelvis cause instability and loss of balance in the frontal plane in the lower limbs. Therefore, football players with hyperlordosis should pay more attention to the changes in the proximal region to prevent instability and injury in the lower limb.