Their study used well trained divers who were being paid to do their best as their diving performances were being videotaped. While there are variables that can speed up or delay the onset of the effects of alcohol, they are minor issues which do not overcome the decrements to the central and peripheral nervous system. Alcohol can be cleared from the blood at a predictable rate. This does not necessarily mean that the decrements in performance have been completely eliminated in that time. Alcohol is a depressant drug that slows certain body functions by depressing the entire central nervous system.
Effects are noticeable after one drink.
The effects are mood elevation, mild euphoria, a sense of well being, slight dizziness and some impairment of judgement, self control, inhibitions and memory. Performance requiring division of attention between two or more information outputs is impaired beginning with a single ounce of alcohol. The deleterious effects of alcohol on performance are consistently underestimated by persons who have been drinking alcohol. Divided attention tasks are found to be affected by alcohol to a greater degree than those tasks with single focus of concentration , i.e. a task such as a headfirst dive into shallow water, with many interrelated decisions necessary to a successful dive, will be impacted to a greater degree than lifting a heavy weight. It is unfortunate that performance and judgement impairing drugs such as alcohol are widely abused in the aquatic environment as well as in the society at large.