cardio or strength training first

If you don't like something change it; if you can't change it, change the way you think about it.
Mary Engelbreit
When I first started working out, I had this question in my mind – Should I do cardiovascular exercise before or after my resistance training?

Some said I should do it before the weight lifting because it helps to warm up my body. Another school of thought believes that, in order to lift heavier weight, I should conserve the energy and therefore, cardiovascular exercise should only be done after that.

Based on my experience, I believe the best choice would be to do your cardio workouts on a separate day from your resistance training workouts, or split your workouts to morning and afternoon. With this option, you can maximize the training of both types of workouts as you will be fresh for both of them. Any time you do one followed by the other, the second one will suffer at least a little (although you may gradually improve your overall endurance this way). If that’s not possible, then it comes down to a question of priorities and goals–for that day.

If your goal is to build muscle mass and strength, you'd probably want to do your weight training first. Weight training utilizes muscle glycogen as its preferred energy source, so if you perform your cardio training after your resistance training, you will tap into your fat stores more readily. However, to increase strength, you want your body to shift into "repair and rebuild" (anabolic) mode as soon as possible after your strength workout, and the best way to make that happen is to eat (simple carbs and protein) as soon as possible (which is being delayed by the cardio). Therefore, a light cardio workout before lifting could be an option too. Don’t try to do a strenuous strength workout after you’ve already tired yourself out with cardio. Your weight training will suffer, and remember; weight training helps build lean muscle mass, which ultimately increases metabolic rate, which will give your body the ability to burn more calories around the clock!

Hence, if your goal is to gain cardiovascular endurance, you'd want to do your cardio workout first.

Here is an order I’d recommend for muscle hypertrophy (growth).

I’d suggest:
FIRST: A warm-up of some kind the first 5 minutes
SECOND: Strength training
THIRD: Cardio
LAST: Stretching

Give a man a fish and you feed him for a day. Teach a man to fish and you feed him for a lifetime.

Chinese Proverb