karen aims for national championship in track and field. her coach, under the guise of strength training, orders her to do squats and air chair exercises, then tries to fuck her when she's exhausted. despite her lactic acid buildup causing her to shake, karen desperately resists. however, her large breasts become her undoing, and her thigh muscles reach their limit. finally, the coach's glans enters karen's vagina, inch by inch. she fails to hold the goal line and the coach's cock starts pistoning deep into her pussy.