diff --git a/src/body/Body.js b/src/body/Body.js
index 36a8c81..698efda 100644
--- a/src/body/Body.js
+++ b/src/body/Body.js
@@ -122,9 +122,11 @@ var Axes = require('../geometry/Axes');
      * @method _initProperties
      * @private
      * @param {body} body
-     * @param {} options
+     * @param {} [options]
      */
     var _initProperties = function(body, options) {
+        options = options || {};
+
         // init required properties (order is important)
         Body.set(body, {
             bounds: body.bounds || Bounds.create(body.vertices),