FIGURE 1-11 Body Cavities. (a) The dorsal body cavity is bounded by the bones of the skull and vertebral column. The muscular diaphragm divides the ventral body cavity into a superior thoracic (chest) cavity and an inferior abdominopelvic cavity.he Thoracic Cavity The walls of the thoracic cavity surround the lungs and heart; associated organs of the respiratory, cardiovascular, and lymphatic systems; the inferior portions of the esophagus; and the thymus.
Half marathon. A half marathon is a road running event of 21.0975 kilometres (13.1094 mi) â half the distance of a marathon. Participation in half marathons has grown steadily since 2003, partly due to the fact that it is a challenging distance, but does not require the same level of training that a marathon does.
Long Walks: The key to getting ready to finish a half marathon is the long walk, progressively increasing in distance each weekend. Over a period of 12 weeks, your longest walk will increase from 3 to 10 miles. Don't worry about making the final jump from 10 miles in practice to 13.1 miles in the race.ut it's handy to know about how fast you are walking, particularly if you are worried about finishing the half marathon in less than four hours. To get a precise measurement of your ability, go to a track for an occasional workout. Outdoor tracks at colleges and high schools are generally 400 meters long.