Stop Doing Cardio Before You Weight Train!
by Larry Pepe
It kills me every time I see it. One person after another shows up at the gym, raring to go. They check in at the front desk, put their gear away and make a beeline for the cardio equipment. Somewhere between 20 and 60 minutes later they drag themselves off that treadmill and on to the gym floor to start the weight training portion of their session. This may be the most common training mistake I have seen in roughly 15 years of training in gyms from New York to California. There are a number of reasons why this training sequence can not only minimize your results but also holds the potential for injury.
Let's make a few things clear before we get started. If you want to warm up by doing 5 minutes of cardio before you hit the weights, power to you. If it makes you feel better prepared to train hard and get the most out of your weight training, great. In colder climates, especially with the fall and winter seasons upon us, this may even be advisable. But remember, we're talking about a cardio warm-up before training, not a cardio session aimed at burning fat. That will come after you train, not before, if you are sequencing the workout properly.
NUTRITIONAL REASONS
Ever heard that you will burn more fat if you do cardio on an empty stomach? Wrong. You will burn more fat if you are depleted of carbohydrates when you do cardio. Protein and dietary fats don't affect the equation. If you wanted to, and it didn't bother your stomach, you could drink a high protein/very low carb protein drink or eat a chicken breast or a piece of lean red meat minutes before you started cardio and you'd still burn the same amount of fat. But, if you have a piece of fruit or a cup of rice before that same session, you won't.
When you eat carbohydrates, the body stores them in the form of glycogen in your liver. Then, as you need to use them for energy, the glycogen stores are used until they are depleted. The problem is that the body will not burn fat until the glycogen stores are depleted. In other words, until you burn all your stored carbs, the body will not turn to your fat stores for energy and no fat will be burned. Now for the really bad news. Studies have indicated that it can take as much as 29 minutes of cardiovascular activity to deplete your glycogen stores. So, when you did that 30 minute cardio session after eating carbs sometime within several hours of beginning the session, you burned fat for a whopping minute--ONE MINUTE.
Does that mean that the session was a total waste of time. No. There are two benefits to cardiovascular work. In addition to burning fat, you elevate your metabolism every time you do cardio, which enhances your body's ability to metabolize food and burn fat for several hours after the session. You'll get that benefit regardless of whether your glycogen stores are full or depleted. But, if you are going to spend the time doing cardio in the first place, why settle for only half the benefit? You're going to work just as hard and spend just as much time either way.
While glycogen (carbs) will deprive you of the full benefit of your cardio, it has the opposite effect on working with the weights. Remember that the benefits to weight training are building/maintaining lean muscle tissue and elevated metabolism. This is anaerobic activity, not aerobic activity like cardio. Therefore, you don't weight train to burn bodyfat. Rather, you do it to build muscle.
When you weight train (anaerobic activity), the body's preferred energy source that enables you to train hard and be and stay strong for the workout is--you guessed it--carbohydrate. So, if you train before you do cardio, the glycogen necessary for productive workouts is both available and used. As you train the glycogen is used for energy and depleted. Ah! Depleted glycogen. Exactly where you want to be when you start cardio (aerobic activity) so that you can BURN FAT!
PRACTICAL REASONS
In addition to the nutritional reasons we've covered, there are other practical considerations that dictate doing your weight training before your cardio. Have you heard about or witnessed many people injuring themselves walking on a treadmill or stairmaster or riding a bike? Me neither. In the grand scheme of things, cardio may be tedious at times, but the risk of injury is pretty slim. Now, how many times have you seen or heard someone talk about pulling this or that or experiencing some discomfort because of something they did while weight training? Hopefully not too often, but a helluva lot more than with cardio. So, you'd have to agree that between the two, there is a greater risk of injury with weight training than there is with cardio. Given that fact, doesn't it make the most sense to weight train when you are in your freshest, strongest condition, both physically and mentally? Obviously, you are going to be in that peak condition when you get to the gym, not after you've done cardio for a half-hour or more at a high enough heart rate to burn fat.
The bottom line: Weight train first, when you have everything in your favor. You'll be mentally and physically fresher and stronger. You'll be in the ideal physiological environment as a result of your nutrition and appropriate use of your glycogen stores for the activities your're engaging in and the respective benefits they offer. Barbells don't just come before bikes in the dictionary. For the MAXIMUM RESULT, they should be sequenced that way in the gym too.
