The new year is among us and with it many individuals are about to embark on a fat loss journey. However, many may be confused as to how to reach their fitness goals. They may be following an IIFYM approach to nutrition (if not, find out your macros here with the IIFYM macro calculator), but question what they should be doing in the gym.

Common questions related to cardio include:

“Should most of my time be spent focusing on cardio or weights?”
“If I am doing cardio and lifting weights which should I do first?”
“How much cardio should I be doing?”
“Should I eat before I do my cardio exercise?”

The purpose of this article is to address these and many other common questions associated with cardio to provide a framework to a cardio plan for successful fat loss.

Should I Focus on Cardio or Lifting Weights?

The cardio vs. weights dilemma is common amongst those beginning their fat loss journeys. So which should it be? To answer this question, let’s take a look at the scientific literature on this topic.

As a whole, many studies find that both cardio and weightlifting can both contribute to weight loss by helping to create a caloric deficit. However, weightlifting often results in a significantly greater change in body composition during weight loss compared with cardio alone. In fact, a recent meta-analysis of over 200 studies on diet and exercise concluded that while adding exercise to a hypocaloric diet improves body composition, not all exercise is created equal.

Intensity of cardio has no effect on fat loss, yet a recent meta-analysis has found that high-intensity cardio interferes less with muscle size and strength gains than lower-intensity forms of cardio [2].

Resistance training was found to be more effective than endurance training for body composition change. Moreover, the change in body composition was greatest when resistance training is performed progressively utilizing whole body and free weight exercises with loads > 75% 1RM [1].

Based on these findings it is clear that for an individual aiming for a maximal change in body composition, progressive weight lifting needs to be the focus in the gym. However, that does not mean that cardio is completely worthless.

Cardio can be a great tool for helping to create a greater caloric deficit and keep weight loss moving. The remainder of this article will focus on how to create the most effective cardio plan for your fat loss goals.


How Much Cardio Exercise?

Weight is lost when energy expenditure exceeds energy intake. Therefore, to lose weight an individual needs to reduce daily caloric intake and/or increase activity.

In fact, cardio is never actually “required” to see weight loss.

However, for many individuals creating an energy deficit large enough to see loss may require a caloric intake that may not be comfortable or sustainable. Therefore, increasing activity in the form of cardio may be beneficial in order to help create an energy deficit. This may allow the individual to eat a bit more food, likely increasing consistency with their nutrition plan.

Could I Create My Entire Deficit Through Cardio Without Lowering My Macros?

Technically yes; however, that may not be in the best interest of maximizing muscle retention during a fat loss phase. A meta-analysis examining the effects of adding cardio to a resistance training plan found that the more cardio an individual performs and the longer the duration of the cardio sessions the more it interferes with muscle size and strength gains [2].

Although exercise is crucial, changing your body composition starts with nutrition. Let us build your ideal diet approach with a Macro Blueprint!

This is not what someone looking to lift heavy weights and hold onto muscle mass while dieting wants to hear! Moreover, a more recent study suggested that the interference effect of cardio on strength training gains may increase the more advanced an individual is in the weight room [3].

So Does This Mean I Shouldn’t Do Cardio?

I wouldn’t take it that far. Cardio can be an effective tool along with reduced caloric intake for creating an energy deficit resulting in weight loss, our coaches usually suggest cardio for those that are pushing to cut their last few pounds while toning. However, based upon this data it may be advisable for those looking to maximize muscle retention during a fat loss phase to keep cardio as low as necessary to see an appropriate rate of weight loss (roughly 0.5 – 1.0 % of body weight weekly for those aiming to maximize muscle retention [4]).


Type of Cardio Exercise?

If you look around the gym, you will see gym-goers performing a wide array of cardio modalities ranging from walking at an incline to taking fitness classes to do a kettlebell circuit and many others.

Which of These is Best?

Fortunately, there is no evidence that any one type of cardio is superior for fat loss over any other cardio modality. Find something you enjoy and do it!

However, it may be in your best interest to schedule your cardio to maximize performance during resistance training. A recent study recruited 11 resistance-trained men and had them perform a full body workout when fresh or after 1 of 4 different types of cardiovascular exercise (a 45min slow run, a 20 min moderate intensity run, high-intensity sprint intervals or an uphill run) in a crossover design [5].

What they found is that all forms of cardio reduced performance in the weightlifting session performed immediately after with squat seeing the largest decrease in performance immediately following lower body cardio.

Therefore, if you are going to lift weights and do cardio exercise within the same session, be sure you are lifting weights first to maximize performance.

What about intensity? If you look at the person walking uphill on the treadmill and the person on the spin bike next to them doing sprint intervals, the individual on the bike clearly appears to be working harder. However, which approach is best?

Oftentimes individuals will do cardio exercises at lower intensities because a greater percentage of fatty acids are oxidized for energy during lower intensity forms of exercise, whereas a greater percentage of carbohydrates are oxidized during higher intensity forms of exercise. When we are dealing with our clients, we choose the best cardio for your lifestyle and goals.

However, studies have found that low-intensity cardio exercise does not result in more fat burned throughout the day due to higher intensity forms of cardio exercise increasing fat oxidation post-workout [6, 7]. Therefore, the “fat burning” heart rate zone that so many people target during cardio truly doesn’t result in a more efficient fat loss.

What’s the Benefit of High-Intensity Cardio Exercise?

Although the intensity of cardio has no effect on fat loss, a recent meta-analysis has found that high-intensity cardio interferes less with muscle size and strength gains than lower-intensity forms of cardio [2]. This is likely due to higher intensity forms of cardio exercise resulting in muscle adaptations that are more related to weightlifting than lower intensity cardio. It also suggests that higher intensity forms of cardio should be performed by those looking to maximize muscle retention during a fat loss phase.

Non-exercise Activity Thermogenesis (NEAT) – Calories burned from all other activity during daily life.

cardio-hill-sprints-trainingOne item that is often overlooked is that high-intensity cardio exercise is more demanding and difficult to recover from. In addition, it may also increase the risk of injury, especially in those who have a history of joint issues.

Therefore, for maximum muscle retention during a fat loss phase, an individual should perform high-intensity cardio if possible. However, if doing so interferes with lifting performance and recovery, lower-intensity forms of cardio exercise are recommended. Ultimately, the intensity of cardio that allows an individual to stay consistent with their exercise plan, expend enough energy to create a calorie deficit and recover to keep performance high during weight lifting will be best for that person.

Should I Do Cardio Exercise Fasted?

Many individuals perform cardio exercise first thing in the morning in a fasted state because they believe it will burn more body fat, but is this true? Should we all be doing cardio first thing in the morning before eating to maximize fat loss?

Looking at the scientific literature, fasted- and fed-state cardio exercise has shown to burn the same number of calories per session [8, 9].

Whether you perform fasted or fed state cardio exercise, you need to make sure that your nutrition post workout is on point. Have one of our coaches create a blueprint built for your lifestyle

A recent interventional study compared the effects of 3hrs of fasted-state cardio vs. 3hrs fed-state cardio during a weight loss trial in young women. After 1 month both groups lost body weight and body fat; however, there were no differences between groups [10].

Taken together, these studies suggest that there is no significant difference between doing cardio before breakfast or after a meal. Whether cardio is performed in the fasted- or fed-state should be based upon individual preference.

What You Need to Know About NEAT


To this point, our discussion of physical activity during a fat loss phase has focused on formal cardio sessions performed in the gym; however, activity performed outside of the gym also plays a large role energy balance.

Total daily energy expenditure (the number of calories burned daily) is the sum of:
– Resting Metabolic Rate – The number of calories burned at rest to keep you alive.
– Exercise Activity Thermogenesis – The number of calories burned during exercise. By increasing the amount of formal cardio an individual does during a fat loss phase they are increasing their exercise activity thermogenesis.
– Thermic Effect of Food – Roughly 10 percent of calories consumed is expended to digest and absorb that food.
– Non-exercise Activity Thermogenesis (NEAT) – Calories burned from all other activity during daily life.

Let our coaches dial in your Blueprint based on your TDEE, taking into account all of your daily activities!

NEAT includes calories burned through involuntary activities like fidgeting, which can differ greatly from person to person [11]. It also includes activity performed while at work, grocery shopping, doing housework and any other activity performed outside of the gym.

When an individual enters a calorie deficit, the body adapts to prevent excessive weight loss in an attempt to maintain homeostasis and stay alive. One of the ways the body adapts is by reducing NEAT [12].

Some of the reduction in NEAT occurs through a decrease of involuntary activities like fidgeting which we have no control over. However, some also occur through the feeling of sluggishness that accompanies a caloric deficit resulting in an individual being less active during daily life.

Therefore, it is important to maintain physical activity levels during daily life throughout a fat loss phase in order to help prevent a large decline in NEAT and maintain a calorie deficit.

Take Home Points

– Cardio is a tool that can help create an energy deficit along with reduced caloric intake. To preserve muscle mass, the focus of the time spent in the gym during a fat loss phase should be resistance training.

– Aim to do the least amount of formal cardio necessary to achieve an appropriate rate of weight loss.

– There is no “best” cardio for fat loss. Find a type of cardio exercise you enjoy and incorporate variety to keep things fun.

– If you do cardio and weightlifting within the same session, lift weights first.

– Fasted cardio is not superior to fed-state cardio for fat loss. Whether cardio exercise is performed before breakfast or after a meal should be based on personal preference.

– Remain active outside of the gym during your cut to help reduce declines in energy expenditure through NEAT.