I have a feeling its harder than it sounds.
endPressUps=false
#loop
loon1 playmove "FXStandToDip"
~2
?endPressUps:exit
goto "loop"
looks good on paper but he does two, stops, stands up, then starts again, which is hardly continuous. Also he drifts to his right.
Edit: Well IW beat me to it ;D ... you'll need to rename his script pushups.sqs and put a delay like this ~1 in the loop.
If you're not sure how to use script files read snYpir's excellent Introduction to code snippets in the Editors Depot.