// clears form field if it contains the default value when the user clicks in it
 function clearMe(formfield){
  if (formfield.defaultValue==formfield.value)
   formfield.value = ""
 }
// Disables the add cardio field unless distance field populated with a number
function validate_cardio(formfield, submit_tag, id){
  if(isNaN(formfield.value)){
     $(submit_tag).disable();
  } else {
      $(submit_tag).enable();
  }
 // why does this steal focus?
 $(id).focus();
}