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.
Add five minutes to your workouts each week, aiming for an eventual goal of 30 minutes of exercise each time. If you can do three 10-minutes workouts each day, youâll get the same benefit as a 30-minute workout, according to the American College of Sports Medicine and the American Heart Association.