Swimming, like any other physical exercise, requires you to keep hydrated. Drinking water before, during, and after your swim can help you avoid dehydration and maintain optimal performance. You should not, however, consume the water from your swimming pool. These waters contain chemicals that are necessary for maintaining the sanitary conditions of your pool. In addition to being toxic if consumed in excess, drinking water can also be harmful if you are not adequately hydrated. Dehydration makes you feel tired and irritable, and it can also increase your risk of injury if you are not careful. By drinking enough water you can prevent these problems from occurring. The best time to drink water is before you get out of bed in the morning and right before you go to sleep at night. It's important to stay hydrated throughout the day too; drinking plenty of water is essential for performing activities without getting tired or feeling sick. Not drinking enough water can lead to serious health issues including headaches, dizziness, confusion, stomach cramps, and diarrhea. So yes, you should drink water while swimming. The more informed you are about your body's needs the better off you will be as a swimmer. Keep these tips in mind as you prepare for your next race or workout pool party and you should have no trouble meeting your fluid requirements.