The ability to float on one’s back should not be the first lesson taught to new swimmers. Unlike floating, other abilities in the water require lots of movement. Floating simply requires the student to relax. As a result, other swimming skills should be taught first. New swimmers will likely have a difficulty staying completely still.
Once the student has become proficient with their other swimming abilities, they will have a much easier time staying relaxed in the water, and as a result, the ability to float on one’s back will at that point come quite naturally. In summary, when teaching a student how to swim, start with lessons such as kicking, holding the breath and paddle stoke and the ability to float will come with added practice and comfort with being in the water.
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Swim Lesson to Teach Swimmers the Back Float