Weight Training or Cardio—What Do I Do First?
I’m often asked that if you want to do weight training and cardio exercise in the same workout session, which one should you do first? One school of thought says that doing cardio first will fatigue you to the point that it will reduce the intensity of the weight training session. Another school of thought states that muscle fatigue from the weight training first will limit your intensity for high-intensity cardio.
Researchers in Japan have studied this question and have concluded that weight training followed by cardio produces the most increase in growth hormone. Growth hormones are vital to producing new muscle and burning fat. An intense weight training session causes the body to use glycogen (carbohydrates) stored in the muscle and liver, causing the body to recruit fat from your fat cells for energy for the cardio session.
For best results in maximizing the production of growth hormones after the weight training session, give yourself 20 minutes rest between the weight training and cardio training sessions. One way to use the 20-minute rest period is to do stretching after the weight training session.