A word that has somehow come to determine if we get fat or not. It’s crazy, all that word actually means is the amount of energy it takes to heat one gram of water 1 °C, but sometimes it seems like that word completely controls our lives.
We want to know how many are in almost every substance we eat, how many we burn doing our workout, and how many to eat to lose or gain weight.
While it sometimes seems that society has taken the focus on calories a little bit too far, the science behind calories and calorie tracking is sound. If you are looking to improve your health and fitness in any way, whether it be losing weight, putting on muscle, or just losing a couple of inches around the waist, it makes sense to know how many calories are in the foods we eat, as well as how many calories we are burning doing various forms of exercise.
In this case, we’re going to focus on weight lifting, and the amount of calories we burn before, during, and after lifting weights.
So how many calories do we burn while lifting weights anyway? It’s complicated, but we’re going to dive into every part of this question. Just like everything else in health and fitness, it depends on a variety of factors, including age, gender, and fitness level, but there are a few specific things we can look at to get a good idea of how many calories the average person will burn while lifting weights.
How Many Calories Do You Burn Lifting Weights?
While the exact number of calories burned during your workout will vary from person to person, fitness professionals will often use METs (metabolic equivalents) to describe the intensity of an exercise, and give us an estimate of how many calories we burn on average from different activities.
METs are used to describe everything from resting, which would be 1 MET, all the way to sprinting, which is around 11 METs. Over the course of an hour, my buddy average Joe, who weights 150 lbs, would be expected to burn around 68 calories, and around 750 if they were somehow able to sprint for an hour (after which poor Joe would probably collapse and die).
When we talk about weight lifting, we need to talk about a range as well, as you can lift at a moderate intensity or have an all-out beast mode intense workout.
Moderate intensity would feel like the weights are relatively easy to lift and you can carry on a halting conversation, but your heart rate is rapidly rising and you break into a heavy sweat. For me, every time I have to carry all my heavy groceries in one trip (because who wants to take two?) up three flights of stairs, that would probably qualify as moderate intensity.
Vigorous intensity is where you are lifting HEAVY, you feel yourself straining to lift the weight, you can’t carry on a conversation, and your heart rate is drastically elevated above resting.
For Joe, my 150 lb friend, if he was lifting at a moderate intensity for an hour (about 3.8 METs) the people at Cornell have put together a calculator that calculates roughly how many calories Joe would burn, which in this case would be around 260 calories.
If Joe was to do vigorous weight lifting instead (around 6 METs), that would probably put him close to a whopping 410 calories burned.
Obviously there will be some variation here, but this gives us a pretty good benchmark for how many calories the average person will burn while weightlifting. To customize it a little bit more to your weight and your activity level, you can check out the online calculator here.
Compound Movements Burn More Calories
So now we know roughly how to calculate how many calories you will burn during your workout but are all weight-lifting sessions created equal?
As we discussed in the first section, lifting at a higher-intensity will burn more calories both during and after a workout. That doesn’t mean that there isn’t a significant benefit to lifting weights at a moderate intensity, in fact if you are a beginner or just getting back into lifting you should definitely start at a moderate intensity to avoid injury and help your body to adapt to your new training routine. However, lifting with higher resistance levels will tend to burn more calories and fat both during and after your workout.
In addition to this, if you can incorporate compound movements into your lifting routine, these will tend to burn more calories than if you were to isolate a single muscle group.
Compound movements are movements that use more than one muscle group to perform the lift. Every time you activate a muscle, your brain is sending a signal to different motor neurons within your muscles telling certain muscle fibers to contract or relax.
Your body and nervous system have to coordinate the movement and recruit the muscles between different parts of your body, which can be very exhausting. Think of the difference in effort between getting one person to march in place or direct a whole marching band, or babysitting one kid versus being in charge of a daycare.
The heavier you lift, the more motor neurons are recruited and the more muscle fibers contract, and if you can get different muscle groups involved then it gets even more fibers involved and uses more energy.
Examples of compound lifts include squats, overhead press, deadlifts, pull-ups, and bench-press, all of which utilize multiple muscle groups workout together.
Examples of non-compound lifts would be bicep curls and tricep kickbacks. Non-compound lifts still have their place in a weight-lifting routine, but because they generally focus on one specific muscle or group of muscles they tend to burn fewer calories than exercises that recruit multiple muscle groups.
The final way to get a bigger calorie-burn out of your workout is to focus on body weight and free-weights, as opposed to weight lifting machines. While weight lifting machines are good for isolating specific muscle groups and helping you to have better form while lifting, body weight and free weight exercises force your body to recruit your core and more deep stabilizer muscles to help you balance the weight and move correctly in the proper plane of motion, and as we now know more muscle recruitment = more calories burned.
The Afterburn Effect of Lifting Weights
Immediately after you finish a strength training session, the body needs to replenish the energy used and repair any damage that the muscles received. In other words, more intense exercises such as weight and strength training burn calories and fat for a longer time post-exercise than lower intensity aerobic exercises.
It’s hard work for your body to build muscle! Because of this, the calorie burning effects of weight lifting don’t end there. Not by a long shot.
When you lift heavy weights, your body doesn’t have sufficient sources of oxygen to fuel the movements you are making, so after it’s used up the initial store of oxygen your muscles will begin using stored glucose (energy) instead.
In addition to this, as you lift you are creating micro-tears in the muscle fibers, which signal to the body that they need to be rebuilt in a stronger, more effective way to deal with the increased load you are putting on your muscles.
Because of this, after you’ve finished your workout your body’s first priorities are to replenish your energy stores, and to rebuild and repair the damage your muscles have received. This leads to an overall increase in your metabolism and calories burned after your workout, a term health professionals sometimes refer to as EPOC (excess post-exercise oxygen consumption).
This afterburn effect, which leads to an elevated metabolic rate and increases the calories that you burn at rest, can last for days after you finish your workout.
One study found that 21 hours post-exercise, the subjects resting metabolic rate was significantly higher after resistance training than resting or basic cardio exercise. Another study found that the next morning after weight lifting, the participants' resting metabolic rate was almost 10% higher than average, 15 hours later! Yet another study found that even 38 hours after they finished exercising, their oxygen consumption was still elevated to statistically significant levels after doing bench, power clean, and dead lift to exhaustion at their 10-rep maximum.
Building Muscle- Your Calorie and Fat Burning Machine
In addition to the calories burned as a direct result of your weight training session, there is an additional caloric benefit that comes from lifting weights. This comes in the form of the muscle that you build as a result of your lift-lifting activities.
Muscle is a very metabolically rich tissue, meaning that it takes a TON of calories just to maintain the muscle that you have.
Health and fitness professionals estimate that it takes anywhere from 6-10 additional calories to maintain each pound of muscle that you currently have. There is a myth that you might have heard in the fitness industry that each pound of muscle burns an additional 50 calories, but these numbers have never been backed by any credible study (if you find one, send it over, I’d love to hear about it!). However, these numbers are only estimates, as there are a lot of other factors changing within your body as you lift weights.
Not only are you building muscle as you lift weights, which is more metabolically rich and will cause your body to burn more calories at rest, but you are also burning away fat, which is generally very metabolically poor. It is estimated that fat only burns about 2 calories per pound, which makes muscle 3-5x more metabolically rich than fat.
As you lift weights you will put on more and more muscle, and as long as you control your diet as you lift you will lose fat and probably weight as well. Over time, your body composition will change in a way that allows you to get much more bang for your buck, allowing you to maintain calorie consumption as you lose weight.
Lifting weights as you lose weight signals to your body that there is a real, recurring need for that muscle, and as you control your diet and work to lose weight the majority of weight lost will be fat.
Additional Benefits To Weightlifting
In addition to the caloric benefits of weight lifting, there are many, many other well-documented benefits of weight lifting, which I will cover more in depth in another future article.
Some of these benefits include stronger and denser bones, decreased body fat, increased joint stability, improved endurance and cardiovascular health, better functional strength (to get those groceries up 3 flights of stairs!), and a longer lifespan. There is even some emerging, although not yet conclusive, research documenting how weight lifting can even help to slow or prevent certain terminal diseases, as well as other conditions like Alzheimers.
Above all, weight lifting will make you look and feel better, and do wonders for your confidence and energy levels throughout the day.
Feel free to reach out to me with any specific questions, I love to hear from my readers. Make sure to subscribe to get the latest tips and tricks, and reach out to me with any questions you have that you would like to see answered in an article.