diff --git a/module/actor.js b/module/actor.js
index ee632aba..de9dc0c8 100644
--- a/module/actor.js
+++ b/module/actor.js
@@ -1086,7 +1086,9 @@ export class RdDActor extends Actor {
       difficultesLibres: CONFIG.RDD.difficultesLibres,
       surencMalusFlag: false, // A ne pas utiliser pour les sorts
       surencMalusValue: 0,
-      surencMalusApply: false
+      surencMalusApply: false,
+      isNatation: false,
+      useEncForNatation: false
   }
     let html = await renderTemplate('systems/foundryvtt-reve-de-dragon/templates/dialog-roll-sort.html', rollData);
     new RdDRollDialog("sort", html, rollData, this ).render(true);
@@ -1114,7 +1116,9 @@ export class RdDActor extends Actor {
         diffLibre: 0,
         surencMalusFlag: (this.data.data.compteurs.surenc.value < 0),
         surencMalusValue: this.data.data.compteurs.surenc.value,
-        surencMalusApply: false
+        surencMalusApply: false,
+        isNatation: false,
+        useEncForNatation: false
       }
       console.log(caracName, rollData);
       let html = await renderTemplate('systems/foundryvtt-reve-de-dragon/templates/dialog-roll-carac.html', rollData);
@@ -1190,7 +1194,10 @@ export class RdDActor extends Actor {
       coupsNonMortels: false,
       surencMalusFlag: (this.data.data.compteurs.surenc.value < 0),
       surencMalusValue: this.data.data.compteurs.surenc.value,
-      surencMalusApply: false
+      surencMalusApply: false,
+      isNatation: name.toLowerCase().includes("natation"),
+      useEncForNatation: false,
+      encValueForNatation: (this.encombrementTotal) ? Math.round(this.encombrementTotal) : 0
     }
       
     if ( competence.type == 'competencecreature') { // Specific case for Creatures
diff --git a/module/rdd-roll-dialog.js b/module/rdd-roll-dialog.js
index 4094754a..18594137 100644
--- a/module/rdd-roll-dialog.js
+++ b/module/rdd-roll-dialog.js
@@ -156,6 +156,10 @@ export class RdDRollDialog extends Dialog {
       this.rollData.surencMalusApply = event.currentTarget.checked;
       updateRollResult(rollData);
     });      
+    html.find('#useEncForNatation').change((event) => {
+      this.rollData.useEncForNatation = event.currentTarget.checked;
+      updateRollResult(rollData);
+    });          
   }
 
   /* -------------------------------------------- */
@@ -164,6 +168,7 @@ export class RdDRollDialog extends Dialog {
     const diffConditions = Misc.toInt(rollData.diffConditions);
     let malusEnc  = (rollData.surencMalusApply ) ? rollData.surencMalusValue : 0;
     let diffLibre = Misc.toInt(rollData.diffLibre);
+    let malusEncNatation = (rollData.useEncForNatation) ?  -rollData.encValueForNatation : 0;
     let diffCompetence = 0;
     if (rollData.competence) {
       diffCompetence = Misc.toInt(rollData.competence.data.niveau);
@@ -172,7 +177,7 @@ export class RdDRollDialog extends Dialog {
       diffCompetence = Misc.toInt(rollData.selectedDraconic.data.niveau);
       diffLibre = RdDItemSort.getDifficulte(rollData.selectedSort, diffLibre);
     }
-    return etat + diffCompetence + diffLibre + diffConditions + malusEnc;
+    return etat + diffCompetence + diffLibre + diffConditions + malusEnc + malusEncNatation;
   }
 
   /* -------------------------------------------- */
diff --git a/module/rdd-utility.js b/module/rdd-utility.js
index 12ea3735..5a27349e 100644
--- a/module/rdd-utility.js
+++ b/module/rdd-utility.js
@@ -150,7 +150,7 @@ export class RdDUtility  {
       'systems/foundryvtt-reve-de-dragon/templates/dialog-roll-encaisser.html',
       'systems/foundryvtt-reve-de-dragon/templates/dialog-tmr.html',
       'systems/foundryvtt-reve-de-dragon/templates/dialog-roll-surenc.html',
-
+      'systems/foundryvtt-reve-de-dragon/templates/dialog-roll-natation.html',
       // Calendrier
       'systems/foundryvtt-reve-de-dragon/templates/calendar-template.html',
       // Conteneur/item in Actor sheet
diff --git a/system.json b/system.json
index 406700a3..87627b3f 100644
--- a/system.json
+++ b/system.json
@@ -2,7 +2,7 @@
   "name": "foundryvtt-reve-de-dragon",
   "title": "Rêve de Dragon",
   "description": "Rêve de Dragon RPG for FoundryVTT",
-  "version": "0.9.92",
+  "version": "0.9.93",
   "minimumCoreVersion": "0.7.5",
   "compatibleCoreVersion": "0.7.6",
   "templateVersion": 51,
diff --git a/templates/dialog-competence.html b/templates/dialog-competence.html
index 62917817..acb64a62 100644
--- a/templates/dialog-competence.html
+++ b/templates/dialog-competence.html
@@ -38,6 +38,7 @@
 </div>
 {{/if}}
 {{>"systems/foundryvtt-reve-de-dragon/templates/dialog-roll-surenc.html"}}
+{{>"systems/foundryvtt-reve-de-dragon/templates/dialog-roll-natation.html"}}
 <div class="form-group">
   <label for="categorie">Etat général</label><label>{{numberFormat etat decimals=0 sign=true}}</label>
 </div>
diff --git a/templates/dialog-roll-natation.html b/templates/dialog-roll-natation.html
new file mode 100644
index 00000000..8eb686a2
--- /dev/null
+++ b/templates/dialog-roll-natation.html
@@ -0,0 +1,6 @@
+{{#if isNatation}}
+<div class="form-group">
+  <label for="xp">Appliquer l'encombrement comme malus à la Natation (-{{encValueForNatation}} ) ? </label>
+  <input class="attribute-value" type="checkbox" id="useEncForNatation" name="useEncForNatation"  {{#if useEncForNatation}}checked{{/if}}/>
+</div>
+{{/if}}