Our hips were designed to generate a lot of power and stability for the rest of our body. So functional hips and surrounding muscles are key for athletes when it comes to power generation as well as the average person for long lasting general joint health and movement into our older years. Unfortunately when we sit for prolonged periods of time, or don't keep the responsible muscles and joints working, we create a weakness that our lumbar spine and knees try to take on. This is actually a great adaptive defense mechanism we have. When one limb or joint is injured our adjacent limb or joint takes over. However, this isn't supposed to be a long lasting solution. When we do this on the long term, we create problems elsewhere, which is why knee pain and low back pain is so prominent nowadays.