Association between back-leg-chest muscle strength and kicking speed in soccer players: an observational study.

BACKGROUND: Several studies have been performed on soccer kicks and stressed the significance of strength/power and coordination between the agonist and antagonist muscles of the lower limb. Along with accuracy, speed is also an important factor in a successful kick. It is reported that trunk musculature, hip and knee extensors of the non-kicking extremity, and hip adductors of the kicking side have a role in increasing the foot velocity while kicking. Since muscles do not work in isolation while kicking and several muscle groups of the leg and trunk have been reported to have a role in high-speed kicks, therefore measuring the combined strength of the leg, trunk, and arm muscles will be an appropriate method to examine their association with the kicking speed. The aim of this study was to examine the association of the combined strength of the lower extremities, back, chest, and arm muscles with the kicking speed of soccer players. METHODS: Forty male soccer players (mean age 15.7 years) participated in the study. The back-leg-chest (BLC) dynamometer (Baseline, New York, NY, USA) and the mobile camera measured isometric muscle strength and kicking speed, respectively. The BLC dynamometer measured the isometric strength of the knee, hip, back extensors, and arm muscles. The kicking speed was measured by asking participants to kick a football in three directions - right, middle, and left - from 11 meters. RESULTS: Significant (P<0.001) negative correlations of isometric strength of the back, leg, chest, and arm muscles and kicking speeds were found in all three directions. In all three correlations, Pearson's correlation coefficient was -0.989. Simple linear regression results showed that 97.8% (adjusted R2) of the variance observed in kicking speed (KS; RT), KS (MD), and KS (LT), was explained by the movement in BLC muscle strength values. CONCLUSIONS: Kicking speeds in the right, middle, and left directions were negatively associated with the isometric strengths of the back, leg, chest, and arms muscles, measured using the BLC dynamometer, in participating soccer players.

The Cardiac Comeback-Beating Stronger: Exploring the Remarkable Resilience of the Heart in COVID-19 Recovery through Cardiac Autonomic Analysis.

Background and Objectives: Analyzing the cardiac autonomic function in COVID-19 patients can provide insights into the impact of the virus on the heart's regulatory mechanisms and its recovery. The autonomic nervous system plays a crucial role in regulating the heart's functions, such as heart rate, blood pressure, and cardiac output. This study aimed to investigate the impact of COVID-19 on heart rate variability (HRV) during a 6-min walk test (6MWT). Materials and Methods: The study included 74 participants, consisting of 37 individuals who had recovered from mild to moderate COVID-19 and 37 healthy controls. The study assessed heart rate variability (HRV) and blood pressure both before and after a 6-min walk test (6MWT). Results: The study found significant differences in a few time domains (SDNN and pNN50) and all frequency domain measures, whereas there were no significant differences in demographic characteristics or blood pressure between COVID-19-recovered individuals and healthy controls at rest. There were significant 6MWT effects on average HR, time-domain (SDNN and pNN50) measures of HRV, and all frequency domain measures of HRV. A significant group × 6MWT interaction was found for SDNN, pNN50, total power, Ln total power, LF, HF, Ln LF, Ln HF, and LF nu. Conclusions: Cardiac Autonomic analysis through HRV is essential to ensure the continued health and well-being of COVID-19 survivors and to minimize the potential long-term impacts of the disease on their cardiovascular system. This suggests that HRV analysis during the recovery phase following exercise could serve as a valuable tool for evaluating the physiological effects of COVID-19 and monitoring the recovery process.

Effectiveness of High Power Laser Therapy on Pain and Isokinetic Peak Torque in Athletes with Proximal Hamstring Tendinopathy: A Randomized Trial.

Athletes such as long-distance runners, sprinters, hockey, and/or football players may have proximal hamstring tendinopathy (PHT). Laser therapy has been shown to be effective in tendinopathies. High power laser therapy (HPLT) is used for the treatment of several musculoskeletal conditions; however, its efficacy on PHT has not been investigated. This study is aimed at examining the effects of HPLT on pain and isokinetic peak torque (IPT) in athletes with PHT. The two-arm comparative pretest-posttest experimental design was used with random allocation of 36 athletes aged 18-35 years into two groups (experimental and conventional group). The experimental group included the application of HPLT for 3 weeks. The conventional group included treatment with a conventional physiotherapy program including ultrasound therapy, moist heat pack, and home exercises for a total of 3 weeks. Pain and IPT of the hamstring muscle were measured before and after the application of the intervention. Pain score decreased, and IPT increased significantly (p < 0.05) after application of HPLT, by 61.26% and 13.18%, respectively. In the conventional group, a significant difference (p < 0.05) was observed in pain scores only, which decreased by 41.14%. No significant difference (p > 0.05) was observed in IPT in the conventional group. When HPLT was compared with conventional physiotherapy, a significant difference was found in pain scores only. HPLT for 3 weeks was found to be effective in improving pain in athletes with PHT. However, no significant difference was found between HPLT and conventional physiotherapy (US, moist heat, and home exercises) in improving the IPT of the hamstring muscle.