Forget the gym —this 20-minute workout builds full-body muscle and boosts your metabolism with just 2 dumbbells

Man doing a dumbbell workout.

Even with the best will in the world, finding the motivation to venture to the gym for a workout during the colder months can prove tricky. But that’s where at-home classes, like this lower body strength workout, step up to the plate.

Using a pair of dumbbells, NASM-certified personal trainer Kayleigh Cohen has created a 20-minute session that has been compiled into an efficient high-intensity resistance training (HIRT) class.