diff --git a/chapters/chapter-2-sorting/2.1-elementary-sorts/insertion.js b/chapters/chapter-2-sorting/2.1-elementary-sorts/insertion.js
index 00a4874..5f7f1f0 100644
--- a/chapters/chapter-2-sorting/2.1-elementary-sorts/insertion.js
+++ b/chapters/chapter-2-sorting/2.1-elementary-sorts/insertion.js
@@ -8,11 +8,13 @@ console.log('> input: ' + input);
 // insertion
 function insertion(input) {
   for(var i = 1, len = input.length; i < len; i++) {
-    for(var j = i; j > 0; j--) {
-      if(input[j] < input[j - 1]) {
-        input[j] = [input[j - 1], input[j - 1] = input[j]][0];
-      }
+    var insertion = input[i];
+    var j = i;
+    while (j > 0 && insertion < input[j-1]) {
+      input[j] = input[j-1];  
+      j--;
     }
+      input[j] = insertion;
   }
   return input;
 }