Determining the hip joint isokinetic muscle strength and range of motion of professional soccer players based on their field position

Background

Soccer players' physical and physiological demands vary based on their field position. Although the hip joint has an important role in soccer, little information is available about the strength and flexibility of the hip joint based on player positions. Therefore, this study aims to investigate the differences in muscle strength and flexibility of the hip joint of professional soccer players based on their field position.

Methods

Ninety-six professional soccer players from Saudi Arabia were divided into four groups (goalkeepers, defenders, midfielders, and attackers), with 24 participants in each group based on their field position. The Modified Thomas test was used to measure the hip extension range of motion (ROM), and muscle strength was assessed by an Isokinetic dynamometer.

Results

There were no statistically significant differences in the isokinetic strength at the hip joint movements between goalkeepers, defenders, midfielders, and attackers (p ≥ 0.05). At the same time, there was a significant difference between groups in the hip extension ROM (p ≤ 0.05). according to different player positions. Post hoc tests reported significant differences between goalkeepers and defenders (p ≤ 0.05), midfielders (p ≤ 0.05), and attackers p ≤ 0.05). At the same time, there were no significant differences between defenders and midfielders (p ≥ 0.05), defenders and attackers (p ≥ 0.05), and midfielders and attackers (p ≥ 0.05).

Conclusion

Even though there was no significant difference in isokinetic strength, there was a significant difference in hip extension ROM among players based on field position. This study may help coaches and trainers to recognize the strengths and weaknesses of players and design training programs to rectify the weaker components and improve players' performance in different playing positions.

Evaluation of the bent knee fall out test pre- and post- an adductor longus tenotomy

OBJECTIVE

To investigate the immediate effect of an adductor longus tenotomy on the results of the bent knee fall out test, and whether there was a correlation between pre-tenotomy measures and the magnitude of change.

DESIGN

Observational study.

METHODS

We included recreational to elite athletes with longstanding adductor-related groin pain (specifically adductor longus insertion pain) undergoing unilateral or bilateral full adductor longus tenotomy. The bent knee fall out test was performed immediately prior and immediately after the surgical procedure. We used Wilcoxon signed-rank test to compare test results pre- and post-tenotomy, and Spearman's rho (rs) to analyse correlation between pre-tenotomy values and the magnitude of change in the bent knee fall out test.

RESULTS

We consecutively included 60 male adult athletes. There was a statistically significant difference (p < 0.001) in the bent knee fall out result from pre-surgery (median 11.5 cm [IQR 9-15], range 5-25 cm) to post-surgery (median 8 cm [IQR 6-10], range 3-15 cm). The mean difference was 3.9 ± 2 cm, range 0-11 cm, corresponding to a large effect size, d = 1.92. There was a moderate correlation between the bent knee fall out measurement pre-tenotomy and the difference from pre-to-post, r_s = 0.75, p < 0.001.

CONCLUSION

The bent knee fall out measurements changed considerably immediately after an adductor longus tenotomy, showing that the test is assessing adductor longus flexibility in male athletes with longstanding adductor-related groin pain. There was a moderate correlation between the bent knee fall out measure pre-tenotomy and the magnitude of change.