All about base excess â to BE or not to BE. In 1948, Singer and Hastings introduced the concept of buffer base (BB). The change in BB from normal was called deltaBB (Î´BB). This change in BB was an expression of the non-respiratory (metabolic) component of an acid-base disturbance.
Empirically from http://www.usaswimming.org/_Rain..., free style is the fastest stroke. This is also called the front crawl (see Front crawl). However as Swimming stroke notes, there are at least 6 variations of that technique.
The back crawl is a swimming technique commonly referred to by the name back stroke. It is the swimming technique which allows to move at the fastest speed while in a backward motion. It is the only standard technique approved by FÃ©dÃ©ration Internationale de Natation (FINA) for moving backwards.