CascadeType jpa/hibernate

@OneToMany(mappedBy = "training", cascade=CascadeType.ALL ,fetch = FetchType.EAGER)
	@Fetch(value = FetchMode.SUBSELECT)
	@JsonManagedReference(value="act-training")
	private List<Activity> activities;

@OneToMany(mappedBy = "activity", cascade = CascadeType.ALL, fetch = FetchType.EAGER)
	@Fetch(value = FetchMode.SUBSELECT)
	@JsonManagedReference(value="act-series")
	@Cascade({org.hibernate.annotations.CascadeType.SAVE_UPDATE})
	private List<Series> series;

@ManyToOne(cascade = CascadeType.ALL)
	@JoinColumn(name = "id_activity")
	@JsonBackReference(value="act-series")
	private Activity activity;

20:39:32,731 INFO  [stdout] (default task-7) Hibernate: insert into trainings (description, duration, training_date, id_user) values (?, ?, ?, ?)

20:39:32,743 INFO  [stdout] (default task-7) Hibernate: insert into activities (id_exercise, id_training) values (?, ?)

20:39:32,746 INFO  [stdout] (default task-7) Hibernate: insert into activities (id_exercise, id_training) values (?, ?)

20:39:32,752 INFO  [stdout] (default task-7) Hibernate: insert into series (id_activity, repeats, weight) values (?, ?, ?)

activitiesService.save($scope.activities[0]).$promise.then(
                function () {
                    // Broadcast the event to refresh the grid.
                    $rootScope.$broadcast('refreshGrid');
                    // Broadcast the event to display a save message.
                    $rootScope.$broadcast('trainingSaved');
                    $scope.clearForm();
                },
                function () {
                    // Broadcast the event for a server error.
                    $rootScope.$broadcast('error');
                });

@POST
    public Activity createActivity(Activity activity) {
		Long id = activity.getId();
        if (id == null) {
        	Activity activityToSave = new Activity();
        	setActivity(activity, activityToSave);
        	activityRepo.add(activityToSave);
            return activityToSave;
        } else {
        	Activity activityToUpdate = activityRepo.getActivityById(activity.getId());
        	setActivity(activity, activityToUpdate);
        	activity = activityRepo.update(activityToUpdate);
        }
     return activity;
    }

public void add(Activity activity){
		em.persist(activity);
	}
	
	public Activity update(Activity activity){
		return em.merge(activity);
	}
	
	public void delete(Activity activity){
		em.remove(em.contains(activity) ? activity : em.merge(activity));
	}
	
	public Activity getActivityById(Long id){
		return em.find(Activity.class, id);
	}