What's your favorite 30 minute workout?

how sitting activity will help in cardio workout

we can go for walking. because it is a best and economocally  safe exercise

I run for 15 minutes then do 15 minutes of crunches, push ups, squats and lunges. If I don't feel like running then I do a Tae Bo workout for 30 mins.

Full body circuit supersets with minimal rest between sets. Choose a push exercise then a pull exercise, for example lunges right into rows. This allows whats called active rest. Chose a moderate weight that allows you to only perform 10-12 reps. Rest for 30-60 seconds, no more, between each superset and then begin again. Do each superset twice until you have worked every major muscle group. Don't worry too much about smaller muscle groups as they are ultimately incorporated into your exercises as secondary movers. As you improve, decrease the amount of time spent resting. You should get a great 30 minute workout. Good luck and have fun