This can be an area of confusion for many people, and understandably so. If you go into your average gym, you will have a wave of muscleheads coming at you with a story about how doing cardio before weight training will sabotage your muscle building efforts and have you looking like a scrawny, pathetic dweeb.
The reality? Not so much.
Cardio After Weights
This is one of the biggest fitness myths I can think of. At first, it seems like there is some sound logic behind it. People who support doing cardio after weights will usually tell you that you need all of your energy to lift weights, and that by doing half an hour to an hour of cardio before that will utilize all your energy (glucose), leaving none for your weight training routine. And, admittedly, having no energy for your weight training routine equals a useless workout.
The problem with this? If you’re eating even a remotely normal diet, you will probably have a pound (about half a kg) of glycogen stored within your body for use as fuel. It’s been proven through research that an hour on a treadmill will burn about 4 ounces (or around 100 grams) of glucose. This leaves you with 75% of your glucose stores intact to be used for strength training. More than enough for even the most intense weight training workouts. Still, if you’re worried about it, you can always replenish yourself with a sports drink or energy pack after your cardio.
Another popular, and admittedly attractive sounding claim, is that by doing your cardio after weight training, you’ll actually burn more fat. The thought process behind this is that by doing your weight training first, you’ll be burning up your glucose supplies (which is also burned first during cardio), leaving nothing but fat stores to be burned. But, as you’ve learned above, your body has more than enough energy up its sleeve to last through both, so this claim is effectively null and void. Remember, the important thing when it comes to burning fat is to burn calories – it doesn’t matter where those calories come from (ie. from fat stores or from glucose).
Cardio Before Weights
The flip side of the coin? Advocates of doing cardio before weight training have some valid points, plus a good amount of research to back them up. They’ll tell you that intensity is extraordinarily important when it comes to cardio. After all; you need to achieve a minimum threshold of intensity to make it worthwhile. While this is true, you can still perform effective cardio workouts after weight training, as I’ve talked about above.
Where doing cardio before your workout really shines is in the following points:
- The amount of energy your body burns after a workout, also known as your EPOC, is higher when you do cardio before strength training.
- Doing your cardio before strength training is physiologically easier than waiting and doing your cardio after your workout.
- Researchers from the Human Performance Research Center at Brigham Young University recommend performing aerobic exercise before resistance training if you have to combine them into one session.
My preference? I like to do my cardio before my workout. After lifting weights I am simply too mentally exhausted to get up on a treadmill and pump out an hour of running. For some reason, it’s psychologically more difficult to leave the cardio until the end of the workout for me.
That said, whenever possible I like to avoid doing cardio and weights in the same workout. Ideally, I’d recommend to split it up into different times in the day, or onto separate days completely. I don’t do cardio and weight training on the same day, and this is based on my current training goals. I’m trying to maintain my body fat and muscle levels. In other words, I’m just working out to upkeep my current physique and stay healthy. Based on your own goals, I’d recommend doing things differently, and I’ve outlined below what you should do based on your own goals.
If your goal is to lose as much fat as possible:
Alternate doing days of cardio and weight training with days of just cardio. Do your cardio before your weight training routine, as fat loss is your main goal, you want to dedicate 100% of your intensity to your cardio workouts.
If your goal is to gain as much lean muscle mass as possible:
Do your cardio after your workout, or on separate days. You’ll want to be 100% for your strength training routine, and there’s no harm doing your cardio afterwards if fat loss is not your main goal.
If your goal is to increase strength:
Definitely don’t do cardio before your workout, as you need to focus all of your effort towards getting those weights up. Ideally, I’d say you should do cardio on a separate day in this situation, but doing cardio after your workout is also an option – if you feel up to it.
If your goal includes 2 or more of the above options:
Do what suits you best, or focus on whatever goal is most important to you. There is no right and wrong here. Change it up on different days, you won’t be doing your body any harm.
My advice is to not get too hung up on this whole issue. It’s not going to make a big difference to your physique either way. I’d say the most important thing would be to do whichever you feel comfortable with. If it’s psychologically too much to do cardio after weight lifting, don’t do it. However, if you find yourself more motivated to do cardio afterwards, then by all means go for it.