No matter how good we get at understanding exercise, there are still some basic things about it that are endlessly vexing. What should come first in your workout, cardio training or strength training? If you or someone you know has recently joined the new “Never Do Cardio” cult, that’s not the answer and please read this first.

When simple questions continue to puzzle us, it is often because the “simple” question has a nuanced answer that is dependent upon numerous factors. And we run into trouble whenever we take what works for an individual and try to make that the template for all of humanity to follow. The “correct” answer to this question can vary from person to person, but by the end of this blog, you should have a better idea of how to answer this question for you.

A recent ACE-commissioned study found that performing cardio exercise after resistance training created a heart-rate response that was 12 beats per minute higher for the exact same workout intensity and duration. This would seem to present clear evidence that cardio should be performed first due to the increase in perceived effort from this shift in heart rate and a potential shifting of the intensity from “moderate” to “vigorous” with no modifications to external intensity. In fact, these were the general conclusions of the study.

However, both Lance Dalleck, Ph.D., the lead researcher in the study, and Cedric X. Bryant, Ph.D., ACE’s Chief Science Officer, agree that the results of this study doesn’t mean every single person should always do cardio first. “When working holistically with a client,” says Dr. Dalleck, “the client’s needs and goals should drive the development of the exercise program.”

Indeed, you can find other, equally well-designed studies that conclude that it’s better to perform strength training first because it depletes the body’s carbohydrates stores, which means it uses slightly more fat for fuel.

Furthermore, most studies have looked at the impact of strength and cardio on a single session as opposed to over a period of time. More recent studies are investigating what is happening to the body’s response and recovery from exercise as a result of strength and cardio together. Some highlights:

-Running negatively affects strength training more than cycling.

-Endurance training volume should be limited to 20 to 30 minutes to minimize potentially negative effects.

-Moderate- to high-intensity endurance training decreases the efficacy of strength training.

Feeling confused? As with most things related to fitness, it is never a good idea to try to turn general guidelines into hard and fast rules that apply to all people. The more deeply you look into this question, “Should I do strength or cardio first?” the clearer it becomes that the only correct answer is: ”It depends.”

It depends on…

Goals: Fat loss? Weight loss? Feel better? Have more energy for recreational activities? Get stronger?

Attitude/Mindset: Hate exercise? Love it? Sort of enjoy it, but sometimes struggle? Don’t like it, but you do it consistently because you want the benefits badly enough to do it? Hate cardio? Hate strength training?

To help you make sense of the best choice for you, take a look at this chart:

Simple is better, but we can’t always reduce a question to a simple answer for everyone. Sometimes, the best answer is “It’s complicated,” which then becomes simple again when filtered through the needs of the individual.