A very common question.
It’s never an either or and shouldn’t ever be the choice you give yourself. Please read all of this.
You are made up of carbon, fat is made up of carbon… you use more carbon the higher your HR is.
Meaning, if you bike for 10 minutes and your HR is at 150, or you do biceps curls for 10 minutes and your HR is at 150…. You’ll theoretically use the same amount of energy. But, doing curls for 10 minutes usually isn’t how we train.
However, muscle is the #1 driver for metabolism, and muscle grows through protein synthesis which is stimulated by resistance and protein consumption. Which is why over time both need to increase.
Can the bike, running, or any form of “cardio” be resistance? Absolutely! Have you seen world class athletes in those sports?
So, there shouldn’t be this seperation of cardio vs weights. Both can do the same thing simultaneously given the right amount of intensity.
The reason why people get skinny from doing loads of cardio is because they’re keeping their HR up longer on average throughout the week than exclusively doing weight, which often has sets and more rest built in.
After reading this, do you have any questions or need additional clarification on?