On Earth all bodies have a weight, or downward force of gravity, proportional to their mass, which Earthâs mass exerts on them. Gravity is measured by the acceleration that it gives to freely falling objects. At Earthâs surface the acceleration of gravity is about 9.8 metres (32 feet) per second per second. Thus, for every second an object is in free fall, its speed increases by about 9.8 metres per second. At the surface of the Moon the acceleration of a freely falling body is about 1.6 metres per second per second.
Physicians and physiologists have warmed to the idea of water walking as therapy and good exercise for people with joint pain and damage for its many benefits, which include: 1  Waterâs buoyancy reduces the impact on joints.  Working out in water can help improve cardiovascular fitness, balance and range of motion.
Aquatic exercise is a low-impact activity that takes the pressure off your bones, joints and muscles. Water offers natural resistance, which helps strengthen your muscles. You can even do aquatic exercise if you don't know how to swim. You might start with water walking. In water that's about waist-high, walk across the pool swinging your arms like you do when walking on land. Avoid walking on your tiptoes, and keep your back straight. Tighten your abdominal muscles to avoid leaning too far forward or to the side.