You must have missed the last Summer Olympics then, because several American champions were failing to cover their hearts and were seen talking during the national anthem. These new athletes have evidently been reminded to show respect.
Gabby kept her hand over her heart for the duration of the anthem. She praised God, even. If you're wondering where her dad is, he's serving in Afghanistan.
Source on the dad being in Afghanistan? Just seems like it would have been mentioned.
I remember as a kid a couple of atheletes in the late ‘60’s olympics holding their fist up during the anthem. Now that was controversial.