We are really good at sitting in the U.S., but even a bit of movement can make you stronger and have better balance. Dr. Brett McIff with the Utah Department of Health says split lunges are a bit more challenging than a typical lunge so adjust your position as needed to really work those legs without overdoing it.
Start with feet shoulder width apart, place one foot on a couch cushion about 4-6” from the floor and the other foot in front on the floor. Keeping your balance, lower your hips toward the floor, making sure your knee doesn’t go past your toes. You will have to move backwards toward the back foot to do this, but keep your balance more toward the front foot. Drive back up to the start position using your hip and leg muscles. You can place your foot on the couch if you need a bit more challenge, but be careful to not overarch your back. Repeat about 8-12 times, 1-3 sets on each side.