The polar m430 gps running watch is a gps watch with wrist based heart rate advanced training features and 247 activity tracking mdash a top level watch for athleats who want morethe polar m430 measures your heart rate from the wrist easily accurately and reliably you can also track your pace distance and altitude with the integrated gps polar m430 running watch smart coaching fitness test with wrist based heart rate a five minute test that measures aerobic fitn