Is it better to do aerobic exercise before or after resistance training?

To settle this chicken and egg question at the gym, ask yourself whether the aerobic exercise you plan on doing involves finer motor skills like coordination or timing. "Motor coordination is temporarily impaired for about 45 to 60 minutes after heavy lifting," explains Declan Connolly, Ph.D., director of the University of Vermont's Human Performance Lab. "Therefore, with activities like racquet sports, basketball, soccer, etc. it's better to save the weightlifting until afterwards." Plus, says Elsworth Buskirk, Ph.D., a professor in physiology at Penn State University, "any type of activity that gets the body warm is advisable before engaging in resistance exercise." Warm muscles are less likely to sustain injuries during a weightlifting session, but they don't necessarily get bigger faster. So, if weights don't interfere with your play time, "whatever you're more comfortable with is fine," says Jay T. Kearney, senior sports physiologist at the U.S. Olympic Training Center in Colorado Springs, "I prefer to lift first, but that's just me."