diff --git a/Shared/SneakGame.cs b/Shared/SneakGame.cs
index d593544..f3dc04a 100644
--- a/Shared/SneakGame.cs
+++ b/Shared/SneakGame.cs
@@ -107,9 +107,11 @@ namespace SemiColinGames {
       }
 
       if (!paused) {
-        float modelTime = (float) gameTime.ElapsedGameTime.TotalSeconds;
+        double modelTime = gameTime.ElapsedGameTime.TotalSeconds;
+        // To prevent huge diffs, never update by more than 4 frames' worth of time.
+        modelTime = Math.Min(modelTime, TARGET_FRAME_TIME * 4.0f);
         Clock.AddModelTime(modelTime);
-        world.Update(modelTime, input);
+        world.Update((float) modelTime, input);
       }
 
       base.Update(gameTime);