Doing leg presses burns way more calories than doing chest flys—even if you do the same number of reps—because your legs use more muscles and keep burning energy longer after you finish.

Scientific Claim

Horizontal leg press exercises elicit approximately twice the total oxygen uptake and energy expenditure compared to chest fly exercises in healthy, resistance-trained men, primarily due to greater excess postexercise oxygen consumption (EPOC) from recruiting larger muscle mass.

Original Statement

“The VO2 increased in all protocols, being higher within the exercises and during EPOC in the LP than in the CF regardless of the RI... Total EE was mainly influenced by muscle mass (p < 0.001) (LP3 = 91.1 ± 13.5 kcal ∼ LP1 = 88.7 ± 18.4 kcal > CF1 = 50.3 ± 14.4 kcal ∼ CF3 = 54.1 ± 12.0 kcal).”

From study:The effect of Between-Set Rest Intervals on the Oxygen Uptake During and After Resistance Exercise Sessions Performed with Large- and Small-Muscle Mass

Evidence Quality Assessment

Claim Status

appropriately stated

Study Design Support

Design supports claim

Appropriate Language Strength

definitive

Can make definitive causal claims

Assessment Explanation

The RCT design, statistical significance (p < 0.001), and direct calorimetric estimation from VO2net support definitive causal language. The claim is appropriately bounded to the studied population and exercises.

Evidence from Studies

Supporting (1)

The effect of Between-Set Rest Intervals on the Oxygen Uptake During and After Resistance Exercise Sessions Performed with Large- and Small-Muscle Mass

Randomized Controlled Trial

Human

2011 Nov

Lifting with your legs burns about twice as much energy as lifting with your chest, mainly because your legs use more muscles and keep your body burning calories longer after the workout.

Contradicting (0)

No contradicting evidence found

Source Study

The effect of Between-Set Rest Intervals on the Oxygen Uptake During and After Resistance Exercise Sessions Performed with Large- and Small-Muscle Mass

Score: 46

DOI: 10.1519/JSC.0b013e318212e415

Similar Assertions

Your body burns more calories after leg presses than after chest flys—even if you rest the same amount—because your legs use way more muscles and need more oxygen to recover.

86%

When doing leg presses, taking only 1 minute of rest between sets makes you breathe harder overall than taking 3 minutes, but this doesn’t happen when doing chest flys—your body handles short breaks better when using smaller muscles.

75%

After lifting heavy with your legs, your body keeps burning extra calories for about 40 minutes—but after doing chest flys with long breaks, it only lasts 20 minutes.

75%

Right after leg presses with only 1-minute breaks, your body gasps for air more intensely in the first minute than if you took 3-minute breaks—but this doesn’t happen with chest flys.

73%