Abstract des Autors

The first part of the article deals with the relationship between visual abilities, technomotor behaviour and the illumination level in tennis. The studies of the illumination conditions in ten regional tennis halls show that about 90% do not fulfil the German DIN-norm criterion for average horizontal illumination (competition: 400 lux, training: 200 lux). The reduction of the illumination level under 200 lux causes a significant decrease in play precision (25% reduced hit quota in a ball-machine test). At increased illumination levels of more than 400 lux a general trend towards raised hit quotas was found. Then the consequences of age-related changes in visual abilities on tennis performance are discussed. In a sample of 207 German and international acting high level tennis players and lower level tennis players age-related significant reductions, for example in static visual acuity, mesopic acuity and contrast sensitivity were found. Finally the role of vision as an essential factor for injury prevention in skiing is discussed. In 29% of the tested leisure-time skiers optical correction of visual acuity was needed. Approximately 40% of the skiers wear either glasses or contact lenses in daily life. However, only about 66% of them wear these on the slopes too. Visual acuity and depth perception have a crucial influence on the ability to recognize potential danger spots on the ski slope. With a reduction in visual acuity, recognition was found to undergo a clear-cut decrease, with potential danger spots being recognized less efficiently and at a later time. An improvement in visual power through filters of various colours was recorded only in unfavourable light conditions and poor visibility (dim light, shade, fog etc.). On average, distinctly more danger spots were recognized with yellow goggles than with colourless filters. On purpose to discover individual deficits early - also with regard to injury prevention - it is necessary to integrate visual abilities in sportmedical checkups and to control eyesight regularly. Verf.-Referat