View full size image. Earth, the third planet from the sun, is the fifth largest planet in the solar system; only the gas giants Jupiter, Saturn, Uranus and Neptune are bigger. Earth is the largest of the terrestrial planets of the inner solar system, bigger than Mercury, Venus and Mars.
Video: Squat exercise. Dr. Laskowski: The squat is a body resistance exercise that works the leg muscles. Specifically, the squat targets the quadriceps and the hamstring muscles. Strengthening these muscles can help protect your knees and boost your performance in a variety of sports.
The hack squat is an exercise in which a person picks up a barbell from the floor behind his or her back and squats.This exercise arrives at its name from the German word hacke, which means ankle. In a traditional hack squat, the barbell sits behind the ankles before being lifted.he hack squat is an exercise in which a person picks up a barbell from the floor behind his or her back and squats.