?
??? ??2008
Guest
I heard that sprint on the track field is the best, but I do not have any track field near my neighborhood. I can only run on the sidewalk or on the grass. I heard that sprint on the sidewalk is not good for the back, but the grass is very uneven in my place. I can only find a few places that are fairly even for grass. So Where exactly I should practice sprint?
Thank you,
Thank you,