Week help: if i go to the gym and do cardio for 45 min for one week with - Help.com

It will probably help

Burn more calories than you consume.

Cardio should help more than weight-lifting for burning fat.
Did you know that an extensive (key-word extensive) 30-minute workout every day for one year will increase muscle mass of the worked-out muscles by 50%? :D

Cardio is essential in losing weight so it’ll help yeah, but you’ll lose weight from everywhere on your body in general. If you want to see results on your belly, you need to do abs work.. It’s important to tone up. Just a few sit ups and crunches to go along with your cardio work out would make a difference and not take much of your time. :)