Maria Sharapova welcomed scientists from the Gatorade Sports Science Institute (GSSI) into a training session where they conducted a sweat test to help her understand how to ensure proper hydration. Through the test, Sharapova learned how well she replaces the fluids and electrolytes she loses in sweat during intense play and reinforced how dehydration can impact performance.

Steve Turano explains that it doesn't matter when you eat, it is a matter of preference to eat before or after a work out. What is important is that you exercise, feel comfortable and remember weight loss isn't based on one event; it is an accumulation of eating and activity over time.

Trainer Les Whitley gives tips on hydrating for runners. Runners should hydrate and drink fluids before a race to counteract moisture lost due to breathing and sweating. Learn to stay hydrated with tips from a professional fitness trainer in this free video on running.

Navy Seal Lt. Dave Castro walks you through 3 lifts that increase your pure strength- squats, shoulder presses and dead lifts.