Whether symptoms during COVID-19 contribute to impaired left ventricular (LV) function remains unclear. We determine LV global longitudinal strain (GLS) between athletes with a positive COVID-19 test (PCAt) and healthy control athletes (CON) and relate it to symptoms during COVID-19. GLS is determined in four-, two-, and three-chamber views and assessed offline by a blinded investigator in 88 PCAt (35% women) (training at least three times per week/>20 MET) and 52 CONs from the national or state squad (38% women) at a median of two months after COVID-19. The results show that the GLS is significantly lower (GLS −18.53 ± 1.94% vs. −19.94 ± 1.42%,p< 0.001) and diastolic function significantly reduces (E/A 1.54 ± 0.52 vs. 1.66 ± 0.43,p= 0.020; E/E′l 5.74 ± 1.74 vs. 5.22 ± 1.36,p= 0.024) in PCAt. There is no association between GLS and symptoms like resting or exertional dyspnea, palpitations, chest pain or increased resting heart rate. However, there is a trend toward a lower GLS in PCAt with subjectively perceived performance limitation (p= 0.054). A significantly lower GLS and diastolic function in PCAt compared with healthy peers may indicate mild myocardial dysfunction after COVID-19. However, the changes are within the normal range, so that clinical relevance is questionable. Further studies on the effect of lower GLS on performance parameters are necessary.