Abstract: Stationary swimming exercises are conducted with a lightweight, compact and portable apparatus which includes a manually collapsible bag formed of flexible sheet material for containing a volume of water, and a tether line which has a rear portion connected to the bag and a forward portion which is connectable to a swimmer. To facilitate filling and draining, the bag has an elongated opening provided with an elongated closing member. According to the method, the bag is filled with pool water by a swimmer standing in the pool, the bag opening is closed, the bag is heaved onto the pool deck, the tether line is connected to the bag and the swimmer, and the swimmer conducts his or her stationary swimming exercises. After exercising, the bag is opened, drained and collapsed to form a lightweight, compact and portable unit.