How many calories does weight lifting burn?

I really doubt it. The only way to determine this is by monitoring your heart rate during the weight lifting process. For me, I burn around 100 calories in a 20 minute session from lifting weights.

It's all a guess. heart rate monitors aren't accurate for it.
and a deadlift burns considerably more energy than a curl, but they take around the same amount of time.
so.

5 cals a minute or less would be my guess

I'd say I burn 500 calories during an hour of body pump class (like circuit training). 500 in 20 mins is VERY high. Even things like zumba and turbo kickbox only burn ~700-800 cals/hour...if you really turn it up!

I started wearing a HRM to Body Pump classes and was surprised to find out I only burn about 300 calories in a 60 min session. The Les Mills websites claim you burn over 500 calories but that maybe only works IF you get your heart rate up enough and IF you're lifting heavy AND keeping up with the tempo AND if you have a guy's metabolism. Of course there's the "afterburn" and the fact that muscle burns fat.
Best thing to do is both cardio and weights.

Guys, this is how you really figure it out.

Formulas available from the Journal of Sports Sciences provide the calorie expenditure calculations for both genders. Men use the equation Calories = [(0.6309 x average heart rate) – (0.09036 x weight) + (0.2017 x age) – 55.0969] x time / 4.184.
Women use the equation Calories = [(0.4472 x average heart rate) – (0.05741 x weight) + (0.074 x age) – 20.4022] x time / 4.184.

Using heart rate to estimate calorie burn only works when the oxygen consumption correlates nicely with the work performed. That means that HRM's are weakly accurate for steady state cardio (where you constantly take in a similar amount of oxygen each minute and do a similar amount of work in each minute) but are totally rubbish for lifting (where your heart rate can be elevated while you are resting and doing no work).

For what it's worth, I think you are better off not estimating the calories burned for each individual weight lifting session. Instead, monitor your weight loss over a week or two, and adjust your calorie intake if the weight loss is too great or too little.

Interesting choice of necrothreads.

And the answer to the question= No. Unless you are very large it is extremely unlikely to burn 500 calories doing 20 minutes of weightlifting. Hell, I don't even burn 500 calories doing 60 minutes of intense cardio.

I know this was posted a while ago, but I will give a little insight. First of all, the person who got the closest was the guy with the formula. The only thing wrong with that formula is that we (common folk) report nutritional information and energy expenditure in Kcal, even though it is commonly referred to as calories. So you're off by 1,000 but you were on the right track. Also, that is the definition of work, but your body uses energy in ways other than just lifting perpendicular to the floor. For example, if you were to get on a rowing machine and row for an hour at high resistance, you would have performed zero work, according to its proper definition (anybody who's been on a rowing machine knows that is grossly inaccurate).

To understand calorie burn due to resistance training, you have to understand what is going on. Your body's muscles are literally tearing, microscopically, when you lift. Your body synthesizes protein to rebuild the muscles back to where it was, and then in layman's terms...adds a little more so it will be better next time. Some experts have said that you continue to burn additional calories from a weight-training session up to 36 hours after you're finished. To highlight that point, I suggest you experiment...get on a treadmill and run at a fast pace FOR YOU, whatever that is, for 30 minutes. See how you feel the next day and the day after that. A few days later, target big muscle groups (chest, quads, hamstrings, core) and lift as heavy of a weight as you can for 10 reps, performing 4 sets of 4 different exercises - USE A SPOTTER. After 3 days of rest, see how you feel. You will notice that the effects of the resistance training are MUCH longer-lasting than the cardio. 500 calories in 20 minutes is bogus, BUT...I'm 6'0 220 lb and typically work out for about 45 minutes with somewhat long rest periods in between sets. I can eat over 3,000 calories a day and still cut weight at about a pound a week. The rest of my day is typically sedentary, and I do little to no cardio. So your guy is wrong, but anaerobic exercise can likely be just as beneficial as light to moderate jogging, if you do it the right way.

I used to run 2-5 miles a day topping out at 10-20 miles per week. Because of a broken ankle I had to stop. I picked up weight lifting because it's pretty stationary. I have to tell you after a hard workout lifting not more than 25 pound on an upper body exercise (arm curls, rowing machine etc.) and doing not more than 40 -60 pounds on a lower body exercise (squats etc.) my body has never looked better. AND while I'm weightlifting, I sweat like I did when I was running and breathe just as heavily and often times not able to have a decent conversation. I by far think weightlifting is a bona fide cardio exercise. When I do circuit training, my heart beat increases, my chest heaves, can't catch my breath and sweat like it's raining outside. I used to have to run every day to keep in shape, I weight lift about three to four times a week for 30 to 45 minutes and I'm two dress sizes smaller and I eat more food. I'm sure this is because of the afterburn of weightlifting. I used to have to run just about everyday to stay in decent shape. The cardio left me looking like a small flabby person. The weights make me look Pah-DOW! You gotta do it. Trust me, weightlifting is cardio. Is it possible to burn 500 in 20 - 30 minutes, probably if you're a professional body builder. I think I can easily burn 250 in a 30 minute session. The fatigue I feel surely confirms it for me. The recovery is longer than if I'd done the running.

So I was at the gym today and my personal trainer off handly said that you burn 500 calories in 20 minutes weight lifting. Is that even close to being true? :huh:

Lol, I'd tell you the truth and say it's burns about 350-450 for an hour of good intensity.

A.C.E. Certified Personal and Group Fitness Trainer
IDEA Fitness member
Kickboxing Certified Instructor
Been in fitness industry for 30 years and have studied kinesiology and nutrition

Nope. But he was probably trying to convince you to lift heavy, which is a good idea for building lean muscle mass. If you were to add muscle mass (and keep it) you'll likely burn well over 500 additional calories over your lifetime. But you won't burn 500 calories during the session. Diet for fat loss, lift for strength gain and lean muscle mass.

I would say that is not true. I often up my burn by doing active rests, where I use my 1 minute recovery period to jump rope (or something of the sort) in between sets. I'm covered in sweat by the end. Even with doing that the burn would be nowhere near what your trainer believes.