Answer: flailed

AnswerCrossword Clue
FLAILED

Swung wildly

FLAILED

Made things harder for the lifeguard

FLAILED

Moved one's arms erratically

FLAILED
Beat
FLAILED
Threshed grain
FLAILEDThreshed.
FLAILEDBeaten.
FLAILEDThreshed
FLAILEDThreshed or thrashed
FLAILEDThrashed (about)
FLAILEDPunched wildly
FLAILEDComplicated a lifeguard's rescue