Q: i have been doing walkand run for a week now do it 4 times a week for 60mins when will i notice weight loss

A: It will depend on your diet just as much or even more than on your running. If you eat too much, no amount of running will help you lose weight. Assuming you eat the same as before (in other words, just keeping your current weight, not undereating or overeating), 4 times/week 60 mins/session can lose you a pound of weight a week or so.

BUT one pound of weight lost is not the same as one pound of FAT lost. Please read this before you continue with your program: http://www.mikesfitness.com/content/burning-calories-muscle-cardio , http://www.mikesfitness.com/content/cardio-does-not-destroy-muscle-when-... and http://www.mikesfitness.com/content/weight-training-better-than-cardio . There you will find why cardio (walking, running, etc.) is NOT the great fat-burner you may think it to be. After you read those, please check out my Nutrition article and Weighttraining article and perhaps reconsider your program. Good luck!