The question of which burns more calories – lower body strength training or upper body strength training – comes up every so often. And the answer is the lower body.

When it comes to weight workouts (aka strength training), the lower body wins when it comes to burning calories … assuming that the same degree of intensity is used when comparing the lower body with the upper portion.

The “lower body” consists of the buttocks muscles, and then the leg muscles (the biggest muscle groups in the legs are the quadriceps and hamstrings). The butt (“glutes”) are bigger and more powerful than people realize.

The biggest muscle group of the upper half is the back muscles, primarily the latissimus dorsi (“lats”), and then second to that is the chest, pectoralis major.

The reason you burn more calories by working the lower portion of the body (again, assuming that intensity level is comparable to both halves), is because, quite simply, the muscles in the butt and legs are bigger and generate the most force.

There’s just more muscle fiber compacted into the thighs, butt and calves, when added up, compared to the muscles in the back, chest, shoulders and arms.

The more muscle that’s worked, the more calories that are burned. You can tell by the way you feel after a hardcore leg workout with weights.

Imagine a 45 minute workout with weights, in which you are squatting with enough weight such that you can barely complete 12 repetitions.

The squats may be done with a free barbell or while holding heavy dumbbells or kettlebells.

Squats engage the major butt muscle (gluteus maximus) in addition to the quads and a little hamstrings recruitment. The core also gets hit.

So you not only have two of the biggest muscle groups going at it (butt and thighs primarily), but you have many muscles working in unison (hamstrings, core, and even, to a minor extent, the calves).

This is a lot of muscle fiber recruitment, which means quite a load of calories burned.

Your next stop is the leg press. This will work the butt, quadriceps, hamstrings and a little bit of the inner thighs (the more your feet point out, the more inner-thigh recruitment, but if your feet are straight, you’ll still get some inner-thigh work, but not a lot).

Many muscles are being worked here, and these include the biggest: thighs and butt. Again, that’s a lot of calories burned.

Next move is the hamstring curl. The hamstrings are a large, powerful muscle group.

You are lifting enough weight to make 8-12 repetitions very difficult, rather than just going through lame motions with a light load.

Next stop is the leg extension (shown in the lower image), which slams the quadriceps. For each of these stations you’re doing 4-5 sets.

Top: hamstring curl. Bottom: leg extension

After 45 minutes, you’re completely toast and your legs feel like jelly.

Now suppose you spend the same amount of time, and same number of sets, focusing on just your shoulders, triceps and biceps.

At the end of the session, if intense enough, you’ll really “feel it” in your shoulders and arms.

However … this feeling will seem isolated and limited, whereas the exhaustion of a leg workout will seem more global to your body.

This is because the glutes, quads and hams make up much more of your body than the shoulders (deltoids) and upper arms (triceps and biceps).

Arm and shoulder muscles don’t burn nearly as many calories as do the hamstrings, quadriceps and buttocks muscles.

Even a back/chest workout won’t match the calorie burn of a buttocks/thigh workout, though don’t blow chest and back off yet … as these are ideal to work on your off-days from legs for high fat burning.

A vicious set of heavy-weight lunges (hold 25-pound dumbbells in both hands, arms straight, while doing walking lunges) will burn significantly more calories than sitting at a preacher curl machine and flexing only your biceps.

Lifting weights (strength training) with the lower body burns many more calories than the upper part.

Lorra Garrick is a former personal trainer certified through the American Council on Exercise. At Bally Total Fitness she trained women and men of all ages for fat loss, muscle building, fitness and improved health.