There's a new shoe in town and it claims to tone your legs.  There are several sneakers on the market that are marketing themselves as the shoe that can tone your body while you walk.
 
The Reebok "Easy Tone" sneakers have balance pods on the bottom of the sneaker to make the walking unstable (definitely not something for older people to use).  This instability causes your other muscles to engage more to compensate and keep you balanced while walking.  Therefore, you engage your Quadriceps, Hamstrings, and Calves more than you would with just walking. 
 
The Skecher's "Shape Ups" make walking like walking in sand, with a dynamic rolling bottom.  You will feel weird at first when you're walking in them.  You actually should start with short walks with them. Yes, you may feel sore afterwards.  They raise you up a few inches because there is about 2 inches of extra rubber and foam inside the bottom of the shoe.  These sneakers also throw you off balance a little and any new muscle on your body will increase your metabolism.  
 
Some fitness specialists suggest these shoes could be doing more harm than good. A study released by the nonprofit American Council on Exercise found that toning shoes failed to live up to promises made by manufacturers.

Some reports of injuries have added to worries. Cindy Pezza, a podiatric assistant in Stoughton, says that patients who have worn toning shoes for several months, particularly the style with rounded soles, have complained of pain and tightness in the heel, calf, and Achilles tendon.

 

I have to say, that some of my clients who are using these different shoes are experiencing not just foot and leg pain, but also neck and back pain.  My personal opinion is to stick with traditional sneakers.