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After-Burn: Time Your Strength and Cardio Training for Maximum Benefit

L.K. Regan

If your regular workout regimen balances resistance training and cardio, then you are faced with a perpetual dilemma: Which to do first? Do you start with cardio as a warm-up for resistance training, or do you burn yourself up on the lifting and then squeeze in the cardio? These are tough questions with very real consequences for your body and your overall fitness. To get the right advice, RealJock turned to Devin Wicks (ACSM-HFI, USAW Club Coach), a director of fitness operations at UC Berkeley and specialty strength coach for some of the University's elite sports teams. His assessment: The order of cardio and lifting depends on the kind of results you want to get. Men who want to get bigger and men who want to get leaner will need different approaches—but both can make significant strides toward their goals by timing their cardio and strength training properly.

Gym Myths 101
Of course, this topic has been discussed in locker rooms around the globe since time immemorial—but not from a particularly scientific perspective, and with a lot of myth-making along the way. To get started, Wicks identifies the three most common myths about the relationship between cardio and resistance training that often cloud people's perception and cause them to make poor choices.

  1. Myth 1: To build mass, do zero cardio: "Many people think that lifting is the only way you can get big; and that cardio leans you up too much; so lifting followed by cardio will always get you lean," Wicks says. It turns out that scientifically this just doesn't hold up—see below for more detail.
  2. Myth 2: Cardio is a great warm-up for any lifting program: Wicks also describes a commonly held notion that one should do their cardio first so as to be good and warmed up for lifting. But this is often overkill. "If I'm working with a client," he says, "I will have them start with just a few minutes of cardio, get into some quick, light weight work, and then get them started on their lifting. That's the right amount and right kind of warm-up for lifting." Note the emphasis on "a few minutes": Forty minutes of cardio is a lot more than a warm-up.
  3. Myth 3: To get lean, do only cardio: Wicks says that "many people think that the only way to get lean is to do cardio. And that's really not true. Or, they think the opposite—that they can only lift and it will lean them up. Also not true." To drop weight and get cut, you want to time cardio and resistance training with each other for maximum metabolic gains.
Science Class
How you combine cardio with lifting has major implications for both your strength gains in your lifting and your ability to speed up your metabolism. "Recent studies have focused on sequencing cardio and resistance training at moderate intensities to investigate the after-burn effect of exercise sequencing," Wicks says. "From these, we can elicit ideas that might apply to individual workouts."

After-burn is exercise's impact on your metabolism after you're done working out. Measuring it is key to understanding the effects of different exercise programs. In particular, a 2005 study published in the Journal of Strength and Conditioning Research measured participants' excess post-exercise oxygen consumption (EPOC)—the amount of additional oxygen the body consumes in the period (in this case 40 minutes) immediately following exercise. This excess consumption is the mark of an accelerated metabolism requiring additional oxygen for fuel, and it is particularly elevated in the 10 minutes immediately following a workout.

The study measured the participants' EPOC under four different scenarios: a resistance training workout; a cardiovascular workout; cardio followed by resistance training; and resistance training followed by cardio. In two of these cases there was a significant increase in EPOC: "Cardiovascular exercise alone, and cardiovascular exercise followed by resistance training, both significantly raised EPOC over resistance training alone or resistance training followed by cardio," Wicks says.

A raised EPOC is a raised metabolism—so with cardio alone and cardio before resistance training, it is possible to really speed up your metabolism in a way that is not possible through just resistance training or resistance training followed by cardio. If you are looking to go lean, this is important information to know, because it gives you a clear method to speed up the leaning up process.

For the muscle-mass seekers, there's a related corollary in the scientific literature: "Separate studies indicate that strength work deteriorates after cardio," Wicks says. For example, after you run, you just can't lift as much—with your legs. This effect is muscle-group specific; you don't want to fatigue your lifting muscles on cardio before you lift. So if you want to get big, you don't want to burn up your strength on the cardio.

The implications of this research are profound. "You can in theory really target your workouts to suit your goals," Wicks says. "If your goal is to get big—to build a lot of muscle mass and bulk up—then you should lift before you do your cardio. That way you use all of your strength on your lifting, and go as hard as you can in the portion of your workout that targets building muscle." You won't necessarily get EPOC gains, but you may not care, if your primary goal is muscle mass rather than leanness.

But for men who want to lose weight or get cut, the opposite is true. In that case, Wicks says, "you should do your full cardio workout first and then strength train—so that you can use the EPOC benefits of cardio followed by weightlifting to boost your metabolism."

The science may be complicated but the bottom line is simple: For muscle mass, start with weights; for weight-loss and leanness, start with cardio first.