Objective: To study the effect of the new coronavirus infection (COVID‑19) on the endocrine system and physical performance parameters of athletes.Materials and methods: The results of an in‑depth medical examination (IME) of 7,509 elite athletes, members of the Moscow national teams, were analyzed for the period 2020 and 2021. The analysis took into account data on sports and infectious anamnesis, results of clinical and laboratory examination of athletes, and spiroergometry data.Results: Among the 7.509 examined athletes, 2.937 (39 %) had a coronavirus infection 3–12 months before the examination, 4.572 people (61 %) did not have a history of COVID. No significant difference was found in the number of athletes who had recovered depending on the sport group, according to the Peliccia classification. A significantly higher prevalence of endocrine diseases and deviations in hormonal parameters was revealed in the group of athletes who had recovered from COVID‑19 (890 people — 30%), in contrast to 15 % (710 people) of uninfected athletes. Statistical analysis among athletes who had recovered from COVID‑19, divided into a group with hypothyroidism and a group without hypothyroidism, showed a significant difference in the results of spiroergometry. Athletes with hypothyroidism showed significantly higher heart rates at rest, at peak exercise, and at the fifth minute of recovery, as well as lower peak oxygen consumption and a decrease in heart rate at the anaerobic threshold.Conclusion: The results of the study showed a significantly higher prevalence of endocrine diseases in the group of athletes who had recovered from COVID‑19, in contrast to uninfected athletes. Athletes with hypothyroidism who have had COVID‑19, according to spiroergometry data, demonstrated a slowdown in recovery processes and a decrease in physical performance, a decrease in aerobic and anaerobic reserves, which indicates a more significant negative impact of coronavirus infection on the physical performance of athletes with hypothyroidism and requires closer attention to this group of athletes to restore their health and competitive potential.