Hi,
Both SportMart and Virtuemart Component don't show reCaptcha on the registration page. If you are seeing reCaptha in the registration form (or the form doesn't work because missing reCaptcha), then it means you are using a 3rd party plugin (most likely "EasyCalcCheck PLUS").
We don't provide free support for 3rd party extensions and their problems.
You should try contacting to that plugin's developers.
Regards.
Support