I don't understand...

eileenschuh

My science mind says it takes a certain amount of energy to lift a certain amount of weight--that is, it requires a set number of calories to bench press a 90 lb barbell. Who (or what) is doing the lifting should not change that energy requirement. Neither should the kind of muscle doing the lifting, how fast it is being lifted, how many times it is lifted, or if there are rests in between repetitive lifts. Barbell, dumbell, bench press, leg curl--lifting 90 lbs is lifting 90 lbs and should require a standard amount of energy. So...why can't we calculate calories burned from strength training? What am I not understanding?

MyChocolateDiet

IDK

MyChocolateDiet

What i do know is that lots of ppl who lift use a method called TDEE in which the workouts are alrwady factored into their cal goals.

mymodernbabylon

Who ever said you can't? It is in the MFP cardio calculator for cardio under strength training - and you do get a calorie burn from it though not as big of a one as things like running or many other cardio exercises.

alanlmarshall

You are not only lifting the weight. You are balancing your body weight, using ancillary muscles, etc etc.

The calories burned lifting are small in number, and harder to estimate outside the laboratory. Too many factors can skew the estimate.

SergeantSausage

Set amount?

Don't make me laugh.

Does a 90% efficient process use the same energy as, say maybe a 27% efficient process?

Work done is always the same. It's the definition of "work".

Energy expended, however, can be just about anything. All over the board.

Anything.

Don't confuse work with energy.

RodaRose

Larger people burn more calories:

TimothyFish

While you're correct that you can calculate the energy required to lift the bar, that doesn't account for all of the energy involved. There is also energy used for the heart to beat and for the lungs to function and to move the weight lifter around while they are lifting. However, the problem isn't that calories can't be calculated for weight lifting, the problem is that MFP chose not to include it in their database.

Liftng4Lis

Ahhhh, you can.

Jruzer

If the weight finishes in the same place it started, technically you haven't done any work on the weight at all.

The work done even in lifting the weight is small. Let's say you bench press 220 pounds (100 kg) 1 meter. Lifting the weight only- not lowering it - does 100 Joules of work. That's 0.24 kCal. So 5 sets of 5 reps would be about 6 kcal.

As was said, the efficiency of your muscles and circulatory system are very important.

kellycasey5

You could very easily wear a heart rate monitor, should you choose to measure your strength training in that manner rather than weight lifted, number of repetitions, speed of lifts, etc.

brianpperkins

kellycasey5 wrote: »

You could very easily wear a heart rate monitor, should you choose to measure your strength training in that manner rather than weight lifted, number of repetitions, speed of lifts, etc.

You could wear a heart rate monitor ... but it wouldn't produce anything reliable. HRMs aren't designed or programmed to calculate anaerobic activity.

eileenschuh

It would seem there are just as many variables in aerobic exercising. Some people put a lot of effort into a hike, some not so much. Some are more energy efficient in the way they move (in fact, our bodies all become more efficient the more often we do an exercise), some weigh more and are therefore moving more pounds through space. Some have efficient lungs and hearts, some not. Many calorie counter apps don't include strength training calorie counts, as if this type of exercise is being silently discouraged as a component of a weight-loss program. After all, it's the user-friendly aspects of the app that are attractive. Who wants to exercise if it's not going to count toward anything or if it's going to take a lot of time and effort to do calorie calculations and enter them? However, nobody has actually come out and said forget strength-training if you're trying to lose weight.

Mr_Knight

eileenschuh wrote: »

So...why can't we calculate calories burned from strength training? What am I not understanding?

You can - it's just a small number and for most situations, not worth messing with.

As a frame of reference, it burns about 1 calorie for a human to lift its own 100kg body by one metre.

Mr_Knight

kellycasey5 wrote: »

You could very easily wear a heart rate monitor, should you choose to measure your strength training in that manner rather than weight lifted, number of repetitions, speed of lifts, etc.

That would give a hugely over-estimated number, as that is using an HRM in ways it was never intended to be used.