When P and S waves hit the surface they transform into surface waves. P and S waves are signatures of fracture rock or earthquake. When a fracture occurs it sends energy out i â¦ n all directions. P, or primary wave is the initial large shock of the earthquake. This travels through anything.
Weekly Cardio Minimum. The Centers for Disease Control and Prevention recommend that all adults engage in at least 2 1/2 hours of moderate aerobic activity per week. If you do intense cardio, you can get away with half that time. You may spread your exercise over as many days of the week as you like, as long as each session lasts at least 10 minutes. In addition, the CDC recommends that all adults engage in some physical activity for 30 minutes a day, at least five days a week.
Although there's really no set recommendation for how many times you should exercise each day to lose weight, there are recommendations for how many minutes you should work out per week. Aim for a range of 150 to 300 minutes per week, suggests the Centers for Disease Control and Prevention.