I trained earlier today and used this new Polar watch I finally pulled the trigger on purchasing. In 73 minutes I burned over 700 calories, kept an average heart rate of 67% age predicted maximum and peaked at 93% of age predicted maximum. Keep in mind, this was a STRENGTH training workout and close to half of it was rest intervals.
Was this an “aerobic” workout? No…but it was certainly beneficial to my cardiovascular fitness and overall work capacity. The lines between strength and cardio are becoming increasingly “blurry”. Yes, if someone has the goal of completing or competing in some type of endurance event, some specific sport which relies primarily on the aerobic energy system, etc., YES, they will have to devote time to training specifically for whatever that is (principle of specificity). But to say strength training has no impact on cardiovascular fitness-or that you need to separate the two-is extremely short sighted.