Evaluation of the learning effect on the six-minute walk distance in adults with long COVID.

At the time of writing this letter, worldwide more than 770 million people had a laboratory-confirmed coronavirus disease 2019 (COVID-19) infection, a condition caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) [1]. Long-term effects of COVID-19 are referred to as long COVID and include fatigue, dyspnoea, muscle weakness, anxiety, depression, and sleep difficulties [2]. The National Institute of Health and Care Excellence (NICE) has defined long COVID as "signs and symptoms that develop during or after an infection consistent with COVID-19, that continue for more than four weeks and are not explained by an alternative diagnosis" [3]. Given that it is a multifactorial condition that can persist for months, the NICE guideline recommends integrated multidisciplinary rehabilitation services in the management of long COVID.