Traditional Weight Training vs Rucking

I decided to try and do a comparison between my typical weight training workout versus a ruck workout of about the same time. Here's the comparison:

Weight Training - 1hr, 6min - 502 active calories, 635 total calories, 119bpm average heart rate

Ruck - 1hr, 6min - 454 active calories, 586 total calories, 111bpm average heart rate, 21 min 11sec average pace, 40lbs

Thinking back to how I felt mentally during the workouts, I have to say that the ruck felt harder to do. The first 30 minutes of the hike was all uphill and I had to stop several time to get my breath. Humidity was also over 90% outside. I'm honestly surprised that I had less active calories burned during my ruck. I bet if I pick up my pace to less than or around 20 minutes that my caloric burn would be closer.

Rucking to say the least is kicking my butt but I really like the challenges it presents. I'm going to try and progress from 20lbs last month to 30lbs in September to 40lbs in October and then finally 50lbs in November which is my hiking goal weight.