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Never ignore the lower body because you're only as strong as your legs.
This short workout allows you to build your leg and butt muscles without any equipment.
I recommend doing it first thing in the morning. But you can also do it during breaks.
What if you can't do some of the exercises because of bad knees? Does that mean you should skip the workout? Absolutely not! Do half range of motion.
For instance, if you're squatting, go down as low as you feel comfortable and then rise.
Enjoy the lower body bodyweight workout for leg and butt muscles.