When I’m pressed for time I’ll do 3 rounds of 15 reps after a 30 minute run and call it a day.
Use a heavy dumbbell, kettlebell or baby and hold it with two hands. I used 20 lbs.
Sit back like you’re aiming to sit in a chair while keeping your knees over your ankles. Hold the squat with your weight in your heels and fire up your abs. Keep your chest up while you curl the weight. Stand and squeeze your butt at the top.