Welcome to the binary world of fitness where the gurus speak in absolutes.
It’s either this or that.
It’s black or it’s white.
One such topic that follows this line of thinking is the age-old fitness question; should I lift weights or do cardio for the best calorie burn?
It makes sense to start at face value.
Using a 160lb man as an example, he’ll burn around 250 calories jogging for 30 minutes at a moderate pace. This increases to 365 calories burned in 30 minutes if he picks up speed to 6 miles per hour according to Medicine and Science in Sports and Exercise. Weight training for the same amount of time torches a much more modest 130-220 calories.
But before you jump to conclusions, let’s dive deep into the murky gray waters of deciding between weights vs. cardio for optimal calorie burn.
The pros of cardio for calorie burning
1. It simplifies hitting a target number of calories to burn
The fitness-minded almost instinctively associate cardio with calorie burning – for good reason too. In the commercial gym setting, every cardio machine spits back the number of calories you’ve burned. You can manipulate this to your heart's content.
Need to burn an extra 500 calories? Keep going until you hit that number. It’s a simple way to effectively (but arguably not the most accurate way) to hit a target number of calories you want to burn.
2. There’s a cardio option for every situation
Need to burn calories in the shortest time possible? High-intensity interval training (HIIT) should be your go-to. This is where you perform bouts of intense exercise for a short period of time, followed by a recovery period. This is then repeated for a number of rounds until you achieve the desired calorie burn or another result such as heart rate, time, distance, etc.
An 8-week study in the journal Medicine and Science in Sports and Exercise tasked a group of men with performing 13-minute HIIT workouts 5 times per week. They compared this with a group who were given a 40-minute traditional, steady-state cardio protocol.
The HIIT group blazed through more calories per minute than the steady state cardio group, burning 180 calories in 13 minutes, compared to the 40 minutes it took the steady group to burn 360 calories. It would have taken the HIIT group only 26 minutes to burn the same number. Impressive. But wait, that number gets even more impressive when you consider the added EPOC (Exercise post oxygen consumption) from HIIT workouts.
EPOC is what is commonly referred to as the “afterburn” effect where you continue to burn a higher number of calories after your workout. LaForgia et al found in their research that EPOC from a HIIT workout meant you’d burn an extra 13% of the calories you burned in your workout over the next 24 hours. Ultimately, that amounts to only around 23 extra calories burned in our above example from the 180-calorie workout, but every little bit helps.
Either way, that doesn’t mean steady state cardio is the loser – this being another subtopic that is too often given the binary treatment – because there are situations when steady state cardio is the best tool in your box. HIIT training is intense and will eventually dig you into a hole that you may struggle to recover from, providing you do it too often.
If you used the 5x a week protocol as the study above did, eventually, you'd run into fatigue, a suppressed immune system and even a decline in performance. That’s according to a study in the journal Frontiers in Physiology. The above side effects are less common for lower-intensity cardio. And some research has shown that it could even enhance recovery.
3. It’s cheap and accessible
Cardio can take an almost infinite amount of forms and to do it you don’t need a gym - heck, you don’t even need equipment. You can turn any movement into cardio if you raise your heart rate enough. Bodyweight circuits, outdoor runs, hiking...the options are boundless.
4. The health and cognitive benefits
Beyond burning calories, research at the Center for Brain Health found doing aerobic exercise, like running on a treadmill or riding a stationary bike for one hour, three times a week, improves brain function, memory and, of course, fitness. The lab coats explained that one of the reasons this happened was thanks to improved blood flow to the brain.
The cons of cardio for calorie burn
You can be fooled into thinking that calorie burn equals weight loss, but scratching beneath the surface shows the lost weight isn’t just fat. Research often shows cardio-only routines cause less weight to be lost from fat and more from lean body mass. In turn, this creates a slowing of the metabolism far more than if you had included weights in your quest for fat loss.
Lifting weights for calorie burn
At face value, weightlifting burns fewer calories than cardio. So, if you’re calorie obsessed, then you’ve found your winner. But, many people want the next layer that extends beyond simply burning calories because the end goal of losing fat while retaining lean muscle tissue is always paramount.
It goes without saying that if you’re looking to build muscle, as well as lose fat, including weights into your sessions is crucial. Even if you think you don’t want to build muscle, there’s an essential reason that’ll change your mind - increased and maintainable fat loss.
A study published in the BMC Public Health journal showed that both cardio-only and weights-only routines burned around the same amount of fat. But, the magic happens when you put the two together, where participants melted twice as much fat.
The cons of lifting for calorie burning
Ultimately, unless you’re lifting weights at a furious pace with great intensity, you won't burn as many calories as cardio.
Also, it’s not as accessible as cardio.
Weight training requires equipment or a gym membership, which for some could be problematic. While there is nothing stopping you from hitting the deck and doing pushups at home or pull-ups at your local park, at a certain point you will need to pick up the weights.
The perfect blend
So, which approach, weight-lifting or cardio, is better for burning the blubber? If you’ve been keeping up, you probably see where this is going.
Another study published in the Journal of Applied Physiology found that 10 weeks of resistance training and cardio, resulted in a greater fat loss than lifting weights alone.
As you can see, shunning one approach for the other isn't the best approach if the name of the game is fat loss.
How can we combine the two without separate routines?
CrossFit is one way. Involving a mix of gymnastics, strength, and intense cardio exercises to condition your body to become good at everything.
The result? You’ll torch calories and body fat.
The Journal of Strength and Conditioning Research backs this up. In just 10 weeks, CrossFit burned 3.7% body fat and saw an 11% increase in participants’ VO2max. A leaner and more fit you. Win-win.
If you don’t like the look or sound of CrossFit, you’ve got options galore.
Circuit classes enable you to get your heart rate up while experiencing the benefits of weight training. Barbell complexes also work like a charm. Complexes involve putting many compound weight exercises together for reps and rounds. It’s like designing your own CrossFit workout without being tied down to a class.
Ultimately, the question of which mode of training burns the most calories is redundant. The question you want to be asking is “Which way of training gives me the most bang for my buck,” and the science overwhelmingly agrees that a combination of cardio and weights is and will always be optimal.