Magnetic resonance (MR) studies suggested cardiac involvement post‐Covid‐19 in a significant subset of affected individuals, including athletes. This brings serious clinical concerns regarding the potential need for in‐depth cardiac screening in athletes after Covid‐19 before return to play. The aim of this study was to gain further insight into the relation between Covid‐19 and cardiac involvement in professional athletes. This was a retrospective cohort study, in which 26 consecutive elite athletes (national team, Olympians, top national league players; median age 24 years, interquartile range [IQR] 21–27, 81% female) were included. At 1.5 T including balanced steady‐state free precession cine imaging, T1 and T2‐mapping using Myomaps software (Siemens), dark‐blood T2‐weighted images with fat suppression, and late gadolinium enhancement (LGE) with phase‐sensitive inversion recovery sequence were used. The athletes had mainly asymptomatic or mild course of the disease (77%). They were scanned after a median of 32 days (IQR 22–62 days) from the diagnosis. MR data were reviewed by three independent observers, each with >10 years cardiac MR experience. Native T1, T2, extracellular volume, and T2 signal intensity ratio were calculated. Diagnosis of acute myocarditis was based on modified Lake Louise criteria. Statistical analyses used were Pearson correlation and Bland–Altman repeatability analysis. At the time of MR the athletes had no pathologic electrocardiogram abnormalities or elevated troponin levels. MR did not reveal any case of acute myocarditis. Cardiac abnormalities were found in five (19%) athletes, including four athletes presenting borderline signs of isolated myocardial edema and one athlete showing nonischemic LGE with pleural and pericardial effusion. Another athlete had signs of persistent lung congestion without cardiac involvement. We have shown that in a small group of elite athletes with mainly asymptomatic to mild Covid‐19, lack of electrocardiographic changes, and normal troponin concentration 1–2 months after the diagnosis, there were no signs of acute myocarditis, but 19% of athletes had some abnormalities as assessed by cardiac MR. Level of Evidence 4 Technical Efficacy Stage 3

Vitamin D does not only influence the musculoskeletal health and mineral homeostasis but it also affects cardiovascular, endocrine, nervous, immune and mental functions, thus it is of considerable importance for both physically active people and elite athletes. However, vitamin D deficiency is common worldwide and results from inadequate endogenous skin synthesis (insufficient ultraviolet B exposure) and diet. To improve the vitamin D status elite athletes often travel to lower latitude during winter. The aim of the study was to evaluate the seasonal vitamin D status in Polish elite athletes according to the sun exposure and oral supplementation. Serum concentration of 25-hydroxyvitamin D (25(OH)D) was measured in the years 2010–2014 in 409 elite athletes, who were divided into the following groups: OUTD—outdoor sports, represented by track and field athletes, who trained in Poland; IND—weightlifters, handball and volleyball players who trained indoors in Poland; SUN—track and field athletes who trained during Polish winter in lower latitude with high sunshine exposure; SUPL—track and field athletes who trained in Poland, had an inadequate vitamin D status (25(OH)D < 30 ng/ml) and were supplemented orally. Inadequate Vitamin D status was observed in 80% of OUTD and 84% of IND athletes in winter, whereas in summer the values amounted to 42% and 83%, respectively. The athletes exposed to sun in winter had significantly higher vitamin D concentration than OUTD group. Oral supplementation improved vitamin D concentration by 45%, whereas winter sun exposure caused its increase by 85%. Except for a few summer months an inadequate status of vitamin D was found in the majority of Polish elite athletes, with the deficiency level being similar to the one observed in non-athletic population. The most serious deficiency was observed in indoor disciplines. Adequate vitamin D status can be achieved by both increased sun exposure, especially in winter, and oral supplementation. Athletes should therefore routinely assess their vitamin D status and be educated how to approach their sunlight exposure, diet and supplementation.

Objectives The aim of the study was to identify predictors determining the course of COVID-19 and antibody response in elite athletes. Design Observational study. Methods Routine medical screening with physical examination, resting ECG, and laboratory tests including antibody response was performed 12-68 days after the diagnosis of COVID-19 in 111 athletes of different sports. Results Clinical symptoms were observed in 84% of subjects. The severity of COVID-19 was mild in 82% of athletes and moderate in 2% of cases. Athletes aged above 26 and male were more likely to develop symptomatic COVID-19. Asymptomatic subjects were younger and predominantly female. In 18% of subjects, symptoms were still present 20 (12-68) days (median and range) since positive diagnosis. Antibody response was observed in 88% of athletes, and its magnitude correlated with time since diagnosis of COVID-19 (RT-PCR), fatigue, fever, and conjunctivitis. There were no differences in antibody response between groups distinguished by sports discipline (p=0.50), and sex (p=0.59), and antibody response did not correlate with BMI (p=0.12), age (p=0.13), the number of symptoms (p=0.43) or their duration (p=0.19). Conclusions The severity of COVID-19 in elite athletes is predominantly mild and without complications. Athletes can return to sport after two symptom-free weeks and additional heart screening is usually not required. Determination of antibodies has been shown to be a useful indicator of a previous COVID-19 disease, and some symptoms can be used as predictors of antibody response.

Objective: The aim of the study was to evaluate the safety and tolerance of influenza vaccines for the northern and southern hemispheres in Polish elite athletes participating in the Rio 2016 Olympics. Design: Prospective, observational, cohort study. Setting: Institutional level. Participants: Ninety-seven athletes vaccinated only with the northern hemisphere vaccine; 98 athletes received the southern hemisphere vaccine alone, whereas 39 athletes were vaccinated with both vaccines. Interventions: The athletes were vaccinated with a trivalent, inactivated influenza vaccine recommended for the northern hemisphere 2015/2016 and then with the vaccine recommended for the southern hemisphere 2016. Athletes kept a diary of adverse events and effects (if any) on training for 6 days after vaccination. Main Outcome Measures: The percentage of general and local adverse events, number of lost or modified training sessions. Results: Significantly more local adverse events (pain and redness) were found in the group immunized with the vaccine for the northern hemisphere. There were no differences in the frequency of general adverse events and influence on training between groups. Of total 273 athletes who had 1911 training days during 6 days after vaccination, 6 athletes (2.2%) lost 13 training days (0.7%) and 16 athletes (5.9%) had to modify 34 (1.7%) training days within first 2 days after vaccination. Conclusions: Athletes tolerated influenza immunization well. If they are going to travel to the other hemisphere during the influenza season, the use of the second influenza vaccine should be advised. Athletes should anticipate modification of trainings for 2 days after vaccination.

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