College coaches and administrators concerned about tweets their athletes might send also should be wary of the ones their athletes receive.

Social media experts point to vitriolic messages directed at football players Andrew Baggett of Missouri and Kenny Bell of Nebraska as examples of why schools should counsel athletes on how to cope with criticism crossing the line from heckling to hate.

Athletes say most of their interaction with fans is positive. Baggett said supportive tweets outnumbered the negative "20 fold" after he missed a big field goal last week and that no one's comment made him feel worse than he already did.

Bell, however, tweeted that he was "truly bothered by hateful comments" after the Cornhuskers lost.