It is best to workout for atleast 60min/day and in those min you should do a warm up and a cool down for 7/-10 min and do cardio for 30 min and for the rest of the time do some stretched because you need to increase the range of motion of your joints. you should also do cardio first because it increases your heart rate and as a result increase the heart’s endurance and also the volume of the lungs increase and exercising also brings the body temperature up and therefore your muscles can be streched at a further distance. 30min of exci a day is good if you want to maintain the benefits of exercise that includes improved heart endurance but 60min/day is ideal for a weight loss plan.I hope this helps …