What are the most common symptoms of sickle cell trait?

None: Sickle cell trait has no symptoms unless there is another blood problem.

Sickle trait: Most people with sickle trait are unaffected by this. For athletes with sickle trait, it is essential to keep well hydrated. Someone with sickle cell trait could have symptoms if they get severely dehydrated (worse if also going to high altitude from low). See http://www.Cdc.Gov/ncbddd/sicklecell/traits.Html for good recommendations.