Cardio Before Or After Weight Training?

Some say to do cardio before weight training, some say to do cardio after weight training, who’s right?

Well, in order to answer these questions, you have to ask yourself what it is you want to accomplish from your weight training program.

That is, are you trying to build strength and muscle? Are you trying to tone up? Are you strictly using weight training to lose weight? Are you trying to build/maintain muscle while burning fat?

You see, both types of exercise, cardio and weight training differ in the kinds of energy systems that each uses.

Cardio is an aerobic exercise. Aerobic activities such as jogging, cycling, and swimming, require a great deal of oxygen to generate the energy needed for prolonged exercise.

The second type of exercise is called “anaerobic exercise” and an example of this type of activity is weight training. Basically, oxygen is not needed to generate energy from this type of activity. Anaerobic activities uses two types of energy systems. The first system, the ATP (adenosine triphosphate) system and relies on creatine phosphate as it’s energy source.

Basically, your body will rely on ATP for the first 5 to 10 seconds of maximum muscular output. Once this period is over, your ATP stores will be depleted and you will more than likely “hit the wall” and become low on fuel. Once your primary fuel is used up, your body will look for another source of energy, which is sugar. Glucose (sugar) is stored in the liver and muscles and will convert to ATP once the initial source of ATP is depleted.

Now, you understand that weight training and cardio exercises use two different energy systems. Alright, personally, I never use cardio before weight training, unless I’m warming up. Why? Well, it comes down to personal experience. I’ve done about a hundred different experiments with cardio to see what is the best time to do it and I always experience my best results after my weight training sessions.

It doesn’t matter if I’m trying to add strength and size to my body or trying to cut off some fat, this seems like the best time for me to do it.

You see, weight training requires 100% of my mental and physical focus and if I’m off by just 1%, it can mean one of two things, poor performance or injury.

Yes, injury. When I show up to the gym, I’m pretty much in a focussed mental state and I know what I have to do.

I’ll hop on the treadmill for about 5 minutes to warm up my body, but afterwards, it’s all business with the weights. As soon as my weight training is done, I’ll do my cardio.

You see, if I have a heavy squat day, I need to concentrate and save every last ounce of energy to try and do 8 repetitions with 400 pounds on my back. This is my sole focus. If I hop on the treadmill for 40 minutes prior to working out, it does two things to me.

First, it gives me too much time to think about the crap that’s happening at work which takes me out of my head and takes my concentration off of the heavy work that’s about to come. This can lead to injuries.

Secondly, although it can give my legs a good work out, I need every last ounce of energy to get that weight up. I’m not doing the treadmill to build my legs, I’m doing squats for that and this is my priority. Doing 40 minutes of cardio can be a little taxing on both, my legs and my wind. I need both to squat with 400 pounds on my back.

Now, if I’m off by just a bit in my physical and mental focus, I’m not going to have a good workout, especially if I’m about to do some heavy compound movements such as the dead lift, squat, or bench press.

However, once my workout is completed, I’ll do my cardio work because I know that this exercise is about endurance and time. It’s at this time that I’ll hop on the treadmill and thing about all the crap at work 🙁

Does this burn more calories or fat? Not sure because it will all depend on the amount of overall calories you expend with weight training. The debate is up in the air about whether or not doing cardio is better for fat loss after a weight training session, but for me, I personally feel that it does.

I mean, really, after you’ve just lifted maximum amounts of weight (for you), your ATP and glucose stores are down. I’m not going to tell you they’re not because if you go hard and heavy for about 45 minutes to an hour, you’re going to be very depleted in glucose (hence the popularity of post workout drinks).

Afterwards, it will take even more energy to get your ass off the gym floor and crawl over to the exercise bike to do 40 minutes of cardio. I personally think that after a hard and heavy weight training session, followed up by a 20 to 40 minute cardio exercise, you’re going to expend more energy, and hence more calories.

Wouldn’t doing cardio prior weight training burn just as much calories? Maybe, but personally, I get much better results by doing weight training first followed up by cardio.

Some may argue that you still have energy to do weight training after cardio but I know that I don’t because I’ve tried it. I simply can’t devote the required mental and physical focus to intense weight training workouts after a 40 minute cardio session.

I know, some of you will argue that you can do the same kind of weight training workouts if you do cardio first but I’m gonna tell you right now that doing 40 minutes on the treadmill will deplete some of your physical resource because what’s the use of this exercise if it didn’t? If you’re tying to get stronger, why not devote all of your energy to exercises that will directly help with this? If you’re trying to tone up and build some muscle, why not expend your energy on exercises that will have a direct impact on this goal?

The most important thing that I can say to you is to experiment. You’re going to find 20 different answers on the internet to this question but my advice to you is to try doing both for two, one week periods.

That is, for one week, try doing cardio prior to weight training and for another week, try doing weight training first. Only you’ll be able to tell what works best for you.

It also comes down to preference. If you find you get a better, overall workout doing cardio first, you may want to stick with it. Personally, doing intense cardio prior to a heavy weight training session drains me. I don’t want to be drained. Therefore, I do more intense cardio sessions afterwards.

Good luck and all the best,


Blake Bissaillion

Blake has been weight lifting for about 28 years now. He's 45 years of age and started seriously training when he was 18 years old.

Blake is the founder of, a successful fitness website that has been around for more than 15 years.