A device for monitoring physiological parameters of a user, comprising a holder (2) provided with at least one display (2a), one wearable or implantable element (400) comprising a sensor for detecting the heart rate (4) of the user during a predetermined period of time of wakefulness and/or sleep of the user, connection means (3) of the holder (2) to the wearable or implantable element (400), at least one processing unit (5) of the data detected by said sensor (4) to determine the heart rate variability HRV of the user during said predetermined period of time., said display (2a) being suitable for displaying at least one first indicator (7) of the state of psycho-physical stress of the user, in relation to said predetermined period of time, understood as a set of symptoms caused by an imbalance of the Autonomic Nervous System (ANS), said state of psycho-physical stress being determined based on the level of heart rate variability HRV detected by said sensor (4). The processing unit (5) is suitable for defining the aerobic threshold of the user and the detected state of psycho-physical stress and for generating at least one workout program for the user and/or one parameter representative of the intensity of the workout that the user must carry out in relation to the determined aerobic threshold value and level psycho-physical stress.Linvention se rapporte à un dispositif permettant de surveiller des paramètres physiologiques dun utilisateur, et comprenant un support (2) doté dau moins un écran (2a), un élément à porter ou à implanter (400) comportant un capteur (4) conçu pour détecter la fréquence cardiaque de lutilisateur pendant une période de veille et/ou de sommeil prédéfinie dudit utilisateur, un moyen de connexion du support (2) à lélément à porter ou à implanter (400), et au moins une unité de traitement (5) des données détectées par ledit capteur (4) afin de déterminer la variabilité de la fréquence cardiaque (HRV) de lutilisateur pendant ladite période préd
