Q: What is the difference between walking 6 kms in 50 minutes and walking the same 6 kms in an hour (relatively at a slower pace)?

A:The difference in walking at a slower pace is that you will be spending less effort. Because the heart and lungs do not have to work so hard as walking faster, the system will not be as efficient as if you were walking faster. That is one of the aims of regular cardio-vascular exercise, to improve the different systems so that they work at optimum level and are ready to face high degrees of excitement, either positive or negative.