adjust the firmness (JumpSport Fitness Trampoline Mode 250)

My order has arrived. The default setting is Soft Setting. In the menu, it says "if you wish to change the firmness of your reboounder, turn it upside down, Then pull cord tighter to different knot. It looks simple, but there are so many cords and it will take a while to reset the knot for each cord. Any suggestion on that? I want to set it to medium.

我做廣播操最後一節：20 分鍾。

所有跟帖： 

• 不需要重新打結了嗎? Mine only has one knot on each cord. -kathyzh- ♀ (0 bytes) () 07/24/2015 postreply 16:47:52

• Model 250 does not have three settings -kathyzh- ♀ (242 bytes) () 07/24/2015 postreply 16:56:52

• so you can not change the setting？ -蕭紫箬- ♀ (0 bytes) () 07/24/2015 postreply 17:52:10

• 借貼問一下，跳完後後頸椎有點不舒服，正常嗎？以前沒有發現頸椎有問題，還是慢慢適應就好了。 -愛吃甜食- ♀ (0 bytes) () 07/24/2015 postreply 18:35:49

• I jump for about 20 minutes, no 頸椎問題. Do you do some other exerc -kathyzh- ♀ (0 bytes) () 07/25/2015 postreply 07:14:03

• 我準備跳一個月試試看，我現在每天跳兩次，每次15分鍾。跳的時候覺得頭有點震，這兩天好像適應點了。 -愛吃甜食- ♀ (0 bytes) () 07/25/2015 postreply 08:23:08

• 我在考慮買你的這個型號，JumpSport Fitness Trampoline Mode 250 還是Costco: Jump -longnv- ♀ (27 bytes) () 07/25/2015 postreply 07:39:55