The biology and medicine of sailing

The physiological demands of sailing are highly specific, varying with wind conditions, type of craft, and crew position. In a light wind, the only physiological variable yet shown to influence performance is the resting blood sugar. Under high wind conditions, the skipper should be light (less than 60 kg), but crew members should be heavy (greater than 80 kg). Height does not seem a great advantage to crew, possibly because they then lack the muscular strength to exploit the added leverage. Muscle strength, endurance and a tolerance of anaerobic metabolism are all desirable attributes of crew, and competitive performance can be improved by a winter training programme that develops these aspects of muscle performance in the abdominal and thigh regions. The skipper must meet intense and prolonged cerebral demands in the face of periodic isometric work; performance may thus be helped by ingestion of carbohydrate over the course of a race. The ability to sustain isometric contractions in the 'hiking' position may also be improved if the muscles are preloaded with glycogen. The combination of a heavy body build, above average age for an athlete and sustained isometric contraction probably makes the yachting enthusiast vulnerable to ischaemic heart disease. Advisors to a sailing team must further take account of the risks presented by immersion in cold water, loss of sleep, circadian variations of performance over an event, and problems of motion sickness in rough weather.     

Special diagnostic procedures in sports medicine

In summary, there are a number of imaging procedures available to support the physician in his or her evaluation of sports injuries. Conventional radiographs remain the primary imaging examination. Specialized radiographic projections will often provide additional pertinent information. A fluoroscopic examination or conventional tomography may provide a cost-effective method of clarifying subtle post-traumatic changes. The use of the more sophisticated and costly imaging procedures should be reserved for those cases in which a diagnosis cannot be made with simpler technology. CT scanning, by virtue of its ability to image in the axial plane, has proved to be an effective method of documenting injuries particularly in complex bony anatomy such as the spine, wrist, elbow, and hips. CT arthrography provides diagnostic information about intra-articular structures. MRI is emerging as an excellent method of noninvasively imaging injuries to soft-tissue structures such as tendons, ligaments, and cartilage. The advancements in MRI technology that are projected for the future may expand the range of usefulness of this modality and decrease the current high cost of these procedures. Radionuclide scanning with Tc99m diphosphonate compounds has proved to be an efficient method of localizing subtle bone pathology and providing a "road map" for further analysis with additional imaging techniques. The cost-effective use of all of these imaging procedures is predicated on an understanding of their usefulness in the diagnosis of each clinical problem and the judicious use of each procedure to fit the needs of the individual patient.     

Computed tomography in various fields outside medicine

CT has been widely used for non-medical purposes, for which, as in medicine, it has the advantage of being non-destructive and having a high spatial and density resolution. CT may help to generate 3-D views which could otherwise be obtained only by dissecting the object. There is almost no limitation with regard to X-ray exposure and scanning time. Dedicated techniques, e. g., rotating the specimen between stationary tube and detector, have been developed. Micro-CT may provide a spatial resolution up to 1 µm. Fields where CT has been successfully applied are archaeology, soil science, the timber industry, biology, industrial X-ray inspection and aviation security.     

Computed tomography in various fields outside medicine

CT has been widely used for non-medical purposes, for which, as in medicine, it has the advantage of being non-destructive and having a high spatial and density resolution. CT may help to generate 3-D views which could otherwise be obtained only by dissecting the object. There is almost no limitation with regard to X-ray exposure and scanning time. Dedicated techniques, e.g., rotating the specimen between stationary tube and detector, have been developed. Micro-CT may provide a spatial resolution up to 1 microm. Fields where CT has been successfully applied are archaeology, soil science, the timber industry, biology, industrial X-ray inspection and aviation security.