As my lovely wife reminded me, "biweekly" can mean either once every two weeks or twice a week. Fortunately for me (and everyone who has to smell me), we get two 2-minute showers per week, to conserve both water and fuel.
One big asset for a 2-minute shower is liquid soap. I can turn on the water and get wet in about 15 seconds, then turn off the water and lather up and shampoo my hair. When I'm ready, I can turn the water on and take my time rinsing off and relaxing in the warm water.
It's amazing how nice a 2-minute shower can be!