The mean score is 60 out of 100 and the standard deviation (in other words, the variation in the scores) is 15 marks (see our statistical guides, Measures of Central Tendency and Standard Deviation, for more information about the mean and standard deviation).
What Are the Six Different Types of Swimming Strokes? Swimming provides all-around, low-impact body conditioning as well as exciting competition. Competitive swim meets allow only four strokes -- butterfly, backstroke, breaststroke and the crawl. Two other strokes -- elementary backstroke and sidestroke -- contribute to swimming longer distances, as different sets of muscles are used. The fastest stroke for most swimmers is the front crawl.
The flutter kick in a front crawl. In swimming strokes such as the front crawl or backstroke, the primary purpose of the flutter kick is not propulsion but keeping the legs up and in the shadow of the upper body and assisting body rotation for arm strokes. The legs are extended straight backwards in line with the body.