health app walking and running distance showing wrongly

Health app on iphone 6 is showing inaccurate walking and running distance. It was working fine with iOS8.1.

Noticed the issue when upgraded to iOS8.2, the walking and running distance was showing very high values. May be its counting when riding a car etc.,

Upgraded to iOS8.3 and still the issue is not resolved.

Any suggestions what may be the issue and a possible resolution. Thanks.