Toning shoes—walking shoes with a specially rounded sole—are popular with fitness enthusiasts.
Background
Research shows that the major leg muscles of people walking in toning shoes receive no more exercise than those of people walking in normal walking shoes.
Surprising Claim
Many people experience a strengthening of their major leg muscles after switching to toning shoes.
Evaluate
Given that studies show the shoes themselves don't actually exercise the major leg muscles more, what else could be different about people who switched to toning shoes? Maybe they get more excited to exercise or motivated, since they see themselves wearing athletic gear?
Goal
Find something else that's happening with the people who switched that would explain why they experience a strengthening of major leg muscles.