This exercise works on the glutes, hamstrings, and quads. Your legs/knees might be affected by injuries leaving you to opt in for the right leg exercises.

Planks are the ultimate test of total-body strength—not just your core. Slowly raise your right foot and place your right toe on your left heel. Low Plank with Single Leg Crossover. Low plank hold with knee flex Walking, jogging, and many other exercises require your body to engage the quads of one leg while engaging the hamstrings of the opposite leg. Start in a low plank position. A personal trainer breaks down how to do proper planks and the muscles that planks work. Repeat as many times as you can with good form. Hold for ten seconds and repeat on the left. Low Plank with Toe/Heel Touch. Begin in a low plank position on your toes and forearms. Read more to learn the top leg exercises for seniors with bad knees!
Effects of Low Plank Hold with Knee-Flex. 5. 6.