You guys say that you don´t start to burn fat untill you have done cardio for 20 minutes. So if I´m going somewhere and it takes less than 20 minutes to walk, like 15 minutes Won´t I burn any fat then? If it takes less than 20 minutes does it mather if I walk or take the car? If I walk many times on one day and on those times it takes less than 20 minutes haven´t I lost any fat?