In 5/3/1 it recommends 2 miles of weighted walking. Is there anything special about the weight vest or is it acceptable to just fill an old backpack up with bricks?
personally, if I walk with a heavy pack on my back I get back pain.
The vest, since the weight is distributed front and back, seems to keep my center of gravity the same and I don't get the back pain.
Walk with the weight vest.