It is becoming increasingly evident that sleep plays an essential role for human health, and it represents an important biophysiological variable for athletes' well-being and recovery. The International Olympic Committee recently highlighted the importance of obtaining sufficient sleep volume and quality among athletes, but acute sleep deprivation is not unusual. Several factors, both endogenous and exogenous, are able to negatively influence sleep in athletes: body temperature, altitude, chronotype, training volume, anxiety, westward and eastward travels, and many others.

Since December 2019, when a new coronavirus (SARS-CoV-2) was originally revealed by an ophthalmologist in Wuhan (Hubei province, China), a related severe acute respiratory syndrome - namely COVID-19 - has been spreading at a pandemic rate, putting global health systems under unprecedent pressure. Italy, as the first Western country tremendously hit by this disease outbreak, has become the iconic resilient outpost under international policymakers' attention. When initial clusters were identified, restrictive actions to curb isolated upsurges of infection were taken by the health region system of Lombardy, thereafter, were extended to all northern Italy and to the entire country. From February 21, when the first Italian COVID-19 case was diagnosed in southern Lombardy, to March 22, when Italian's government restrictions to contain the pandemic were extended, prohibiting all non-essential business activities and banning all movements of people nationwide, the country faced an unchartered scenario, from several standpoints, along with the psychosocial one.

Inevitably, the Covid-19 outbreak has largely influenced the daily life of athletes too. Therefore, the primary aim of this study was to examine the differences in athletes' sleep quality, quantity and training volumes during the social confinement due to the virus outbreak. For this purpose, a survey will be used. This variables will be evaluated in 3 different time frames: 1) May 2020; 2) September 2020; 3) January 2021.

Inclusion Criteria:

• male or female gender.
• age between 18 and 40 years old.
• elite athletes (competing at national or international level).
• no cognitive impairments.
• at least 6 years of practice of a specific sport discipline.
• affiliated to CONI (Comitato Olimpico Nazionale Italiano).

Exclusion Criteria:

• age under 18 years old.
• part-time workers.
• injury or any clinical condition affecting training routines (and sleep).
• pregnant women.

Italian elite athletes will be recruited.