Most experts have an opinion on this sequence—the best order for burning fat, building muscle, or overall effectiveness. But, if you want more energy, researchers at the University of Rhode Island found that 20 minutes of cardio followed by basic strength training works best. Participants reported having more energy throughout their workout when they did cardio first, compared to subjects who did cardio last. Why? Strength training breaks down your muscle fibers (which is great for strength training), but this leaves you fatigued during your aerobic exercise afterward.
If you’ve been doing weights first, your cardio session may suffer. When you're tired during cardio, you’ll compensate by slowing down, putting in less time, and ultimately burn fewer calories. Switch it up for a high-energy, calorie-blasting workout.