Pathology in any segment of the spine-pelvis-lower extremity may impair the global postural balance, leading to compensatory alterations in other parts. The aim of this study was to compare the pelvic movements of patients suffering from knee osteoarthritis with patients who underwent total knee arthroplasty and healthy controls.

Hamstring strains commonly occur late in football matches. Hamstring injury risk rises with age and fatigue. This study investigated eccentric hamstring strength and perceived hamstring soreness after a football match in younger and older players. Maximal eccentric hamstring strength and perceived soreness were assessed in younger (n = 11, 20.2 ± 1.1 years, total playing time: 34.5 ± 8.8 min) and older (n = 10, 27.4 ± 3.7 years, total playing time: 44 ± 10.5 min) professional male football players before and after a friendly match aimed at selecting the primary team for the upcoming season. A two-way mixed model ANOVA was employed for statistical analyses. Furthermore, Hedges’ (adjusted) g effect sizes were calculated to evaluate the magnitude of effects. The older group experienced significant reductions in absolute (-20 N ± 38.5, g = 0.58, p = 0.027) and relative (-0.26 N/kg ± 0.5, g = 0.43, p = 0.038) maximal eccentric hamstring strength, while younger group showed no changes (absolute: 3 N ± 36.1, g = 0.07, p = 0.773; relative: -0.037 N/kg ± 0.54, g = 0.07, p = 0.783). There was no statistically significant difference between groups for the absolute (p = 0.195; g = 0.45) and relative (p = 0.226, g = 0.43) eccentric strength changes. On the other hand, both groups reported increases in perceived hamstring soreness after the match (older: 29% ± 14.1, p < 0.001; younger: 40% ± 14.9, p < 0.001), with the younger group reporting more significantly higher soreness changes than the older group (11% ± 17.2, p = 0.025). A significant negative association existed between age and eccentric strength changes (R = -0.447, R2 = 0.2, p = 0.007). The older group showed significant declines in eccentric hamstring strength after the match, with age as a predictor. Specialists should focus on enhancing eccentric strength in older players and monitor their recovery to minimise injury risk. Future psycho-physiological research should examine muscle soreness perceptions and force production in fatigued younger and older football players. The results must be interpreted with caution due to the shorter playing time, unaccounted match workload, and limited sample size. Moreover, future research is necessary, including workload and performance metrics over a longer play duration for each player, with a larger sample size to achieve more reliable conclusions.

Aims: This study aimed to investigate the relationships between various isokinetic strength ratios-including conventional concentric (CVRC) with separate velocities, conventional eccentric (CVRE), functional deceleration ratio (FDR), and mixed ratios (MR, MR_cross)-and two clinical performance measures; closed kinetic chain upper extremity stability test (CKCUEST) and Unilateral Seated Shot Put Test (USSPT). Methods: Thirty-two asymptomatic young adults (18-40 years) were assessed using an isokinetic dynamometer (Cybex NORM®, Humac, CA, USA). Seven isokinetic ratios were calculated from peak torque values. CKCUEST and USSPT were used to measure upper extremity stabilization and power, respectively. Normality was tested via Shapiro-Wilk and histogram analysis. Pearson correlation was applied for CKCUEST, and Spearman correlation for USSPT. Results: No isokinetic ratio was significantly correlated with CKCUEST. For USSPT, CVRC_240 showed the strongest negative correlation (p=-0.585, p<0.001), followed by MR_cross (p=0.467, p=0.007), CVRC_120 (p=-0.422, p=0.016), and CVRC_60 (p=-0.378, p=0.033). Conclusion: CVRC_240 and MR cross ratios demonstrated moderate associations with segmental upper extremity power. These findings support their use as performance markers for ballistic functional tasks, while their lack of correlation with stabilization tests suggests different neuromechanical determinants.

Background and Objectives: Hamstring strain injuries (HSIs) are frequent and recurrent in athletes who perform high-speed running. The long head of the biceps femoris (BFlh) is often affected by HSIs. While the Nordic hamstring exercise (NHE) is used for prevention, evidence shows it mainly activates the semitendinosus (ST) instead of the biceps femoris (BF). It was argued that hamstrings may contract isometrically during sprinting’s late swing phase; exercises like the single-leg Roman Chair-Hold (RCH) might better mimic sprinting. Limited electromyographic (EMG) data compare NHE and RCH. This study examined EMG activation of BF and ST during both exercises in athletes. Materials and Methods: Thirty-six professional handball players (17 females, 19 males) were randomly assigned to NHE (n = 18; mean age 22.1 ± 3.9 years) or RCH (n = 18; mean age 22.6 ± 4.9 years). A wireless EMG system recorded dominant leg BFlh and ST activity, normalised to maximal voluntary isometric contraction (MVIC%). NHE participants completed one set of ten repetitions; RCH participants performed three sets of ten repetitions with progressive loads (bodyweight, +10 kg, +20 kg). Results: RCH led to a significantly higher mean BFlh activation in the third set with +20 kg weight compared to NHE (72.9% versus 46.5%; p < 0.001, g = 1.52). BFlh activation steadily increased across RCH sets, coinciding with additional load increments (p < 0.001). Conversely, NHE produced greater ST activation than the RCH at the first set, where RCH was performed with only bodyweight (p < 0.001). Conclusions: NHE primarily activates the ST, while RCH gradually increases BFlh activation, particularly under load. Future research should investigate which exercises are more effective at reducing HSIs to draw more robust conclusions based on the study’s findings.