just wondered which is better for slimming/toning up really.

always used treadmill but an old (well current as well but gets worse somethimes especially in winter) back injury is rearing its head again.
although im fine with weights running is becoming very uncomfortable (base of spine goes solid so feels like i have no cushioning)

now im going to see a specialist hopefully this weekend for sports massage and possible spine realignment (have had back checked out and they cant do much for it, just said carry on as i am)

now i was talking to a bloke at the gym and he said why dont i use the cross trainer. now iv always thought (without using them) they were a waste of time but after going on one for a few mins my legs (tops) were burning and i was sweating like a...well you know what.

what im wondering is, what is better? surely they both have up sides but is the cross trainer doing more for me (it certainly keeps the impact off my back)