I get asked a lot by women if they should do cardio to lose weight and my answer is always that they will see better results from weightlifting.  This is hard for them to comprehend because they feel like they are burning more calories during a cardio session than a weightlifting one.

Now there are two issues here.  First, if you lift weights you should be lifting heavy and not have a lot of downtime between sets.  If you follow along with the P90X resistance training workouts, you’ll see that Tony Horton keeps you moving from one exercise to another quickly.  When you have a weight workout like that, I assure you that you will sweat and burn a lot of calories during the workout.

Secondly, what you need to look at is the post workout impact.  EPOC refers to the amount of oxygen burned post workout and oxygen consumption is directly related to how many calories you are burning. From the article Resistance Training and EPOC by Jeff M. Reynolds and Len Kravitz, Ph.D.:

Also, it appears that resistance training produces greater EPOC responses than aerobic exercise (Burleson et al. 1998). The research suggests that high-intensity resistance exercise disturbs the body’s homeostasis to a greater degree than aerobic exercise. The result is a larger energy requirement after exercise to restore the body’s systems to normal (Burleson et al. 1998), and thus an explanation for the higher EPOC. The underlying mechanisms that cause the higher EPOC observed in resistance exercise include elevated blood lactate, and an increase in circulating catecholamines (epinephrine and norepinephrine) and anabolic hormones.

This has been studied with the same outcome for both men and women.

Now add to this the fact that weightlifting will add lean muscle mass to your body and that will slowly increase your basal metabolism over time.  So weightlifting gives you a longer post workout ‘burn’ and adds muscle which increases your metabolism.

Finally, weightlifting puts the lean mass where you really want it.  As your upper and mid back get a little broader, your waist looks smaller.  And as you burn off the unwanted fat, you end up looking curvy.

Short bouts of high intensity interval training are also recommended for increasing EPOC and, consequently, fat burning.  Lower intensity cardio is good exercise but for best results, go higher intensity for, typically, 40 minutes or less and you’ll see great results.