Impact of COVID-19 infection on sports performance of elite university athletes.

BACKGROUND: Cardiopulmonary functions of athletes can be affected by the Coronavirus disease 2019 (COVID-19). This study aimed to investigate athletes' pattern of returning to sports after COVID-19, their experience of COVID-19-associated symptoms, and the disturbance in sports performance caused by the symptoms. METHODS: Elite university athletes who were infected with COVID-19 in 2022 were recruited for the survey and the data for 226 respondents were analyzed. Information about COVID-19 infection and the degree of disturbance in ordinary training and competition was collected. Their returning pattern to sports, the prevalence of COVID-19 symptoms, the degree of disturbance in sports by related symptoms, and factors associated with disturbance in sports and fatigue were analyzed. RESULTS: Results showed that 53.5% of the analyzed athletes returned to ordinary training immediately after quarantine, while 61.5% experienced disturbance in ordinary training, and 30.9% experienced that in competition. Most prevalent COVID-19 symptoms were lack of energy, easy fatiguability and cough. Disturbance in ordinary training and competition were mainly related to generalized, cardiologic, and respiratory symptoms. Women and those with severe and generalized symptoms had significantly higher odds of experiencing disturbance in training. Those with cognitive symptoms had higher odds of being "fatigue case." CONCLUSIONS: More than half of the athletes returned immediately to sports after the legal quarantine period of COVID-19 infection and experienced disturbance in ordinary training by related symptoms. Prevalent COVID-19 symptoms and the associated factors causing disturbance in sports and fatigue case were also revealed. This study will be helpful to establish the safe return guidelines essential for athletes after COVID-19.

Comparison of scapular position in elite tennis players with and without shoulder impingement: A case-control study.

BACKGROUND: To maximize the ball velocity in the tennis sever, the shoulder plays a key role in the kinetic chain. But shoulder inefficiency leads to shoulder injuries such as shoulder impingement syndrome (SIS). Thus, to verify the scapular movements during the tennis serve could help prevent shoulder injury in tennis players. OBJECTIVE: This case-control study aimed to verify the scapular movements during flat first serve for elite tennis players with shoulder impingement syndrome compared to those without it. METHODS: Eight elite tennis players (4 males and 4 females) with SIS and 8 elite healthy players (4 males and 4 females) performed flat first serves, and the three-dimensional scapular kinematic data was recorded using the Qualisys motion capture system through spherical reflective markers including the acromion marker cluster. RESULTS: The scapula was more internally rotated (median difference: 10.40∘) in the male players with SIS than in those without it at the maximally externally rotated humerothoracic joint during flat first serve, and female players with SIS (median difference: 7.16∘ and 11.28∘, respectively) had more internally rotated scapula at the maximally externally rotated humerothoracic joint and ball impact. CONCLUSION: Increased scapular internal rotation may be something that affects shoulder injuries in the overhead sports, and it may help to prevent and rehabilitate overhead injuries including SIS.

The short-term effectiveness of scapular focused taping on scapular movement in tennis players with shoulder pain: A within-subject comparison.

This study aimed to investigate the short-term effectiveness of scapular focused taping (SFT) on scapular position and kinematics during the tennis serve among professional players with and without shoulder pain. The cohort included 7 players who had no history of non-shoulder pain (NSP) and 6 players with shoulder pain (SP). All participants performed tennis flat serves while the Qualisys motion capture system recorded three-dimensional scapular kinematic data according to the International Society of Biomechanics recommendations. SFT was applied to the participants' torso aligned with the lower trapezius, and the same movements were repeated. In the SP group, the scapula was tilted more posteriorly after the application of SFT as compared to before at ball release and maximally externally rotated humerothoracic joint during tennis serve (t = -5.081, P = .004 and t = -2.623, P = .047, respectively). In the NSP group, the scapula was tilted more posteriorly with SFT as compared to without at first 75% timing of the cocking phase and maximally externally rotated humerothoracic joint (t = -3.733, P = .010 and t = -2.510, P = .046, respectively). And the SP group exhibited a more rotated scapula externally after the application of SFT as compared to before at Ball impact (t = 5.283, P = .003). SFT had a positive immediate effect on the scapular posterior tilting and external rotation during certain phases of the tennis serve among tennis athletes with and without shoulder pain. These findings may help clinicians and sports practitioners to prevent and rehabilitate shoulder injuries for overhead athletes. Level of evidence: Level III; Case-Control Design; Comparative Study.

Optimal relative workload for managing low-injury risk in lower extremities of female field hockey players: A retrospective observational study.

ABSTRACT: Our study aimed to investigate the relative workload that is related to the injury in lower extremities of female field hockey players and to identify the optimal ratio of acute to chronic workloads (ACWR) depending on the playing position to manage low risk of sports-related injuries.Data were collected using a global positioning systems unit on a full-time basis and during competition among 52 players who were enrolled in Korea National Team. The ACWR was calculated by dividing the most recent 1 week workload by the prior 4 weeks workload. Injury risk was calculated for each category from very low to very high based on a z-score.In striker and midfielder, the injury risk was the lowest in the moderate-low category of total distance covered, meters per minute (MpM), repeated high-intensity effort bouts, and acceleration bouts, and the moderate-high category of high-intensity running distance (HID). The injury risk of a defender was the lowest in the moderate-low category of HID and MpM.The ACWR in total distance covered, MpM, repeated high-intensity effort bouts, and acceleration bouts should stay within the moderate-low category in striker and midfielder positions and HID and MpM in defender positions in order to manage low-risk of non-contact and soft tissue injuries in female field hockey players.

The effect of external cues with vibratory stimulation on spatiotemporal gait parameters in chronic stroke patients.

[Purpose] The aim of current study was to investigate the effect of external cues using vibratory stimulation on spatiotemporal gait parameters in patients with chronic stroke. [Subjects] Thirty patients, who had suffered a stroke, were selected from general hospitals in Seoul, Republic of Korea. [Methods] Each participant was subjected to six walking trials: three trials with vibratory stimulation of the tibialis anterior muscle and three trials without any stimulation. The spatiotemporal gait parameters were measured with a GAITRite system. [Results] The global gait parameters-velocity and cadence-were significantly more increased, and the temporal parameters-step time, stride time, and double limb support-were significantly more decreased with vibratory stimulation of the tibialis anterior muscle than with no stimulation. While single limb support was increased under vibratory stimulation, the difference was not significant between the two groups. The spatial gait parameter-stride length-showed a significant improvement; however, there was no significant enhancement in gait symmetry with regard to step length and step time [Conclusion] These results indicate that the application of external cues using vibratory stimulation during gait may control gait parameters and improve gait performance. Thus, this intervention could be used for gait rehabilitation in chronic stroke patients.