iPhone 5 Image Stabilization

Everytime I watch a recorded video of me just walking around using the rear facing camera, I notice that evertime I take a step in the video the video blurs just slightly. Is it normal that a litle jostle to the iPhone 5 (as caused by walking and taking steps) while video recording will produce a slightly blurred video at the time of the jostling. This issue is really concerning me since some people say that the iPhone 5 has great image stabilization. Thanks in advance!