the good thing about the cocept 2 is that it works your entire body. it is new to you so your body will be challenged so you perhaps won’t be able to go as long as doing other cardio stuff. try at least 20 minutes and work your way up. note the adjuster to change the intensity level. the more you put into this exercise, the more you get out of it. you should consider joining a rowing team if you really enjoy it.