diff --git a/back_end/src/main/java/hackathon/FrisbYEE/jpa/metier/Session.java b/back_end/src/main/java/hackathon/FrisbYEE/jpa/metier/Session.java
index ba2a14d..7711c2a 100644
--- a/back_end/src/main/java/hackathon/FrisbYEE/jpa/metier/Session.java
+++ b/back_end/src/main/java/hackathon/FrisbYEE/jpa/metier/Session.java
@@ -32,7 +32,7 @@ public class Session {
     private String groupe;
 
     @ManyToOne
-    private User coach; // un coach par session
+    private Coach coach; // un coach par session
 
     @ManyToMany
     private List<Athlete> athletes = new ArrayList<>(); // plusieurs athlètes par session
@@ -56,4 +56,21 @@ public class Session {
     public String toString() {
         return "Session [id=" + id + " , name=" + name + "]";
     }
+
+    public void setCoach(Coach coach) {
+        if (coach.getRole() != Role.COACH) {
+        throw new IllegalArgumentException("L'utilisateur n'est pas un coach");
+        }
+        this.coach = coach;
+    }
+
+    public void setAthletes(List<Athlete> athletes) {
+        for (Athlete athlete : athletes) {
+            if (athlete.getRole() != Role.ATHLETE) {
+                throw new IllegalArgumentException("L'utilisateur n'est pas un athlète");
+            }
+        }
+        this.athletes = athletes;
+    }
+
 }
\ No newline at end of file
diff --git a/back_end/src/main/java/hackathon/FrisbYEE/jpa/service/UserDAO.java b/back_end/src/main/java/hackathon/FrisbYEE/jpa/service/UserDAO.java
new file mode 100644
index 0000000..5481dbe
--- /dev/null
+++ b/back_end/src/main/java/hackathon/FrisbYEE/jpa/service/UserDAO.java
@@ -0,0 +1,10 @@
+package hackathon.FrisbYEE.jpa.service;
+
+import hackathon.FrisbYEE.jpa.metier.User;
+import org.springframework.data.jpa.repository.JpaRepository;
+import org.springframework.stereotype.Repository;
+
+@Repository
+public interface UserDAO extends JpaRepository<User, Integer> {
+
+}
diff --git a/back_end/src/main/java/hackathon/FrisbYEE/rest/AthleteResource.java b/back_end/src/main/java/hackathon/FrisbYEE/rest/AthleteResource.java
index f539950..d3681a1 100644
--- a/back_end/src/main/java/hackathon/FrisbYEE/rest/AthleteResource.java
+++ b/back_end/src/main/java/hackathon/FrisbYEE/rest/AthleteResource.java
@@ -47,7 +47,7 @@ public class AthleteResource {
     @PostMapping("/create")
     @PreAuthorize("hasRole('Admin')") // Only admin can create??
     public ResponseEntity<AthleteDTO> create(@RequestBody AthleteDTO dto) {
-        Athlete athlete = mapToEntity(dto);
+        User athlete = mapToEntity(dto);
         athleteDAO.save(athlete);
         return ResponseEntity.status(HttpStatus.CREATED).body(mapToDTO(athlete));
     }
diff --git a/back_end/src/main/java/hackathon/FrisbYEE/rest/SessionResource.java b/back_end/src/main/java/hackathon/FrisbYEE/rest/SessionResource.java
index 5ea60dd..9d8a86c 100644
--- a/back_end/src/main/java/hackathon/FrisbYEE/rest/SessionResource.java
+++ b/back_end/src/main/java/hackathon/FrisbYEE/rest/SessionResource.java
@@ -3,12 +3,12 @@ package hackathon.FrisbYEE.rest;
 import hackathon.FrisbYEE.jpa.dto.SessionDTO;
 import hackathon.FrisbYEE.jpa.metier.Activite;
 import hackathon.FrisbYEE.jpa.metier.Athlete;
-import hackathon.FrisbYEE.jpa.metier.Coach;
 import hackathon.FrisbYEE.jpa.metier.Session;
+import hackathon.FrisbYEE.jpa.metier.User;
 import hackathon.FrisbYEE.jpa.service.ActiviteDAO;
-import hackathon.FrisbYEE.jpa.service.AthleteDAO;
-import hackathon.FrisbYEE.jpa.service.CoachDAO;
 import hackathon.FrisbYEE.jpa.service.SessionDAO;
+import hackathon.FrisbYEE.jpa.service.UserDAO;
+
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.http.HttpStatus;
 import org.springframework.http.ResponseEntity;
@@ -29,10 +29,7 @@ public class SessionResource {
     private SessionDAO sessionDAO;
 
     @Autowired
-    private CoachDAO coachDAO;
-
-    @Autowired
-    private AthleteDAO athleteDAO;
+    private UserDAO userDAO;
 
     @Autowired
     private ActiviteDAO activiteDAO;
@@ -43,7 +40,7 @@ public class SessionResource {
     public ResponseEntity<?> create(@RequestBody SessionDTO dto) {
         try {
             Session session = maptoEntity(dto);
-            session.setCoach(coachDAO.findById(dto.getCoachId()).orElse(null));
+            session.setCoach(userDAO.findById(dto.getCoachId()).orElse(null));
             sessionDAO.save(session);
             return ResponseEntity.status(HttpStatus.CREATED).body(maptoDTO(session));
         } catch (Exception ex) {
@@ -96,7 +93,7 @@ public class SessionResource {
             session.setDuree(dto.getDuree());
         }
         if (dto.getAthleteIds() != null) {
-            List<Athlete> athletes = athleteDAO.findAllById(dto.getAthleteIds());
+            List<User> athletes = userDAO.findAllById(dto.getAthleteIds());
             session.setAthletes(athletes);
         }
         if (dto.getActiviteIds() != null) {
@@ -122,7 +119,7 @@ public class SessionResource {
         // Athletes
         if (s.getAthletes() != null) {
             List<Integer> athleteIds = new ArrayList<>();
-            for (Athlete athlete : s.getAthletes()) {
+            for (User athlete : s.getAthletes()) {
                 athleteIds.add(athlete.getId());
             }
             dto.setAthleteIds(athleteIds);
@@ -148,13 +145,13 @@ public class SessionResource {
         session.setGroupe(dto.getGroupe());
         // Coach
         if (dto.getCoachId() != null) {
-            Coach coach = new Coach();
+            User coach = new User();
             coach.setId(dto.getCoachId());
             session.setCoach(coach);
         }
         // Athletes
         if (dto.getAthleteIds() != null) {
-            List<Athlete> athletes = athleteDAO.findAllById(dto.getAthleteIds());
+            List<Athlete> athletes = userDAO.findAllById(dto.getAthleteIds());
             session.setAthletes(athletes);
         }
         // Activites