Why do some people appear to have abs without having to do specific exercises?
We all have a 6 pack generally hiding beneath a layer of fat. Lose the fat, tone the muscles and your 6 pack abs will be visible for all to see. Those that seem to naturally have a six pack will generally be lean and low in fat. For men anything below 12% fat and the 6 pack will be visible, the same being true of women at below 18% fat.