1.If your goal is better endurance, do cardio before weights.
2.If your goal is burning fat and losing weight, do cardio AFTER weights.
3. If you want to get stronger, do cardio AFTER weights.
4.On upper-body strength training days, you can do either first.
5. On lower- body strength training days, do cardio AFTER weights.
6.If your goal is general fitness, do either first, or do the one you like the least first.
—info by American Council on Exercise