dont over-do it, but about 45 minutes a day, if you are doing 15 minutes of slow walking, that is not enough, try for about 45-60 minutes a day, if you want to get fit, walk to the bus or school or go to the gym or play a afternoon sport or go for a bike ride or get an areobics DVD. anything that gets you moving, i find that if you want to watch tv and excersise, do sit-ups for the whole ad break, but build it up dont just do a whole ad break at first, do one ad, then two, then three so on.
1 hour
1 hour
30 min a day
A lab should get an hour to a half hour a day
at least 3 hours
A ten year old boy should receive up to 120 minute a day of exercise to get the muscle working and growing strong. He should also eat alot of proteins and vegetables as well as meat
7 hours a week, for champions
a exercise bike or a treadmill
If a 67-year-old is in reasonably good health, a 2-mile walk should be OK.
3600 hours just kidding it is about 3500 seconds witch is 60 minutes witch is 1 hour
A 13 year old should get plenty of exercise! But should hang with friends and go on Skype
i guess it depends how much you eat, exercise. if you think your over or under wight you should see a doctor.