The expert: Fitness Director Chad Sparling, CWP, CFT
For most all goals I recommend that clients engage in some sort of cardiovascular exercise following a training session. The reason I say following is because of the energy systems that are at play. You have three main sources of energy and two that really matter, 1. creatine phosphate (only last around 10 seconds, not going to get into) 2. blood glucose/sugar and 3. Fat stores.
The benefits from strength training come in the days following the activity. Those muscles need time to recover, thus requiring calories to heal and increased calories/metabolic rate to sustain their new and improved structure. By weight training before cardio you are better able to get the most “bang for your buck.” The first (2nd, not getting into creatine) energy store you will use regardless of the activity is your blood glucose. This is available energy just floating around the muscle body waiting to be used, so why not let the muscle grab onto it during weight lifting, allowing you to get a couple extra reps or pounds. This in turn will give you better caloric burn in the recovery days and long-term progress.
By weight training first and doing cardio after you guarantee that you are not just burning off your breakfast on the treadmill, you put that blood glucose to better use, getting better lifts! You burned up most or all that blood sugar doing a more cellular demanding workout. This means when you hop on that piece of cardio equipment and pop in your headphones you know the only energy source you have remaining is your fat stores!
In summary: Unless your main fitness goal is to improve your cardiovascular performance, I recommend weight training followed by cardio for best results.
Article by Adventure 212 Fitness
Photo Credit: https://www.popsugar.com/fitness/30-Minute-Cardio-Strength-Training-Workouts-44761107