Originally Posted by
gsteinb
strap a HR monitor on and go lift weight. You might notice that, depending on how you rest and superset, that your HR doesn't get all that high. Yet somehow the body is stressed and is sore the next day.
+1. Low HR doesn't mean there's no training load, and doesn't even mean that there's no strain on the heart. It means it's not sustained aerobic exercise. And on the other hand, a high HR doesn't mean you've done an aerobic workout. Check your HR after running a 200m - it'll be pretty high. Doesn't make the 200m an aerobic effort.