Which is better: walking or running?

evolutionary biologists say that walking is the supreme most way of locomotion for humans..
since it uses least energy..
so why do people advice cardiac patients walking ,not jogging?

it is because in cardiac patients every kind of stress to the heart is to be avoided..prolonged running can have a negative effect...Slow and steady wins the race

Running also causes more impact, and is harder on the joints...

I think walking is better. Running speeds up your heart rate and as captainassassin said it is hard on your joints.

Walking, swimming, cycling...running or jogging is best on short grass

Walking briskly for 45 to 60 minutes for Four to Five days a week beats running as running compacts on joints and is boring.
At least with walking you get to see more of the countryside.

Mitch

I lost 10 kgs from walking 5 days a week for an hour and now am 84 kgs which is almost normal for a bloke