how far you can get. when done, swim back downstream for rest. then repeat.
if you are using a swimming pool, you have plenty of options. the first and most obvious is to swim laps up and down the pool. this is of course limited to the length of the pool and the amount of people in it. many swimmers in pools do not like people swimming laps. try to get along. but there are more options to use in swimming pools. you can actually do strength training in a swimming pool. here are a few ideas. you can stand in waist deep water and put your hands on the side 