You know that drinking plenty of water can not only keep you healthy-afterall, water is involved in almost all chemical reactions in the body-but it can also help your slime-down efforts and make your workouts more effective. If you're even mildly dehydrated, you won't have as much energy or endurance to make it through your exercise routine. So, how much is enough? The Best Life guidelines call for drinking at least 48 ounces of water a day, but should you be gulping down more if you work out regularly? Is there an ideal amount you should be consuming for optimum performance and good health? Michelle Hering, M.S., Best Life fitness expert, shares some water wisdom below.

Question: How much water do I need during my workout?

Michelle Hering: Water needs vary from person to person depending on their body mass, metabolic rate, clothing, and even the weather (yes, you still need to drink when it's cold out!). You can use this rough guideline for staying hydrated while working out: Before you begin, drink eight ounces of water, and then during your workout, drink about four to six ounces of water (about five to seven gulps) every 15 minutes. After the workout, follow-up with another eight ounces of water.

A simple way to determine if you're drinking enough during your workout and throughout the day: Check the color of your urine. Rate the color on a scale of one to eight, with one being clear and fully hydrated and eight being yellow/brown, indicating dehydration. (Really dark urine is uncommon, but if you notice that yours is dark, be sure to drink some water, and if it doesn't change, contact your doctor.) The closer to one you are, the more hydrated you are.

Remember, there are a number of factors that could affect your hydration, including your age, medications and health conditions, so it is important to pay attention to your body. Look for signs of dehydration, which include dry skin, dry mouth, chills, head rushes, and skin flushing. If you notice any of these during your workout, make sure to stop and get some water. You'll have a more effective workout if you're fully hydrated.