how mudch cardio to do ? everybody is different on how their body re-acts to different exercises. myself when it comes to cardio , i do not start a good swet until i have been at it for at least 15min. i use the elipic0 trainer (sorry about the spellling) which is a cross trainer. by life fitness i usually set it for 30min but for a good swet 45min at level 18 (which it only goes to 20)my rpm up to 50 and heart rate about 140bpm.also i put it in reverse mode which it will automatically go into after 5-min. pulling back on the handles allows you to use your arms more and leaning forward will hit them glutes. it is a great machine and easy on the joints since there is no impact of weight hitting the ground as in running. there are several programs to choose which i put mine on manuall so i can control the pressure. this is one ofthe best carido machines that i have been on and while you are on it there is a big projection screen in front of you with a good movie on. take a date and just like being at the movies. david