You will be analyzing the hyrdrodynamics of different swimming strokes - Lab Report Example

Lab Report on the Hydrodynamics of Different Swimming Strokes Introduction Swimming performance relies on the ability of a swimmer to minimize hydrodynamic drag in the event of the underwater phases. In which case, posture assumed by a swimmer determines how fast and efficient swimming can take place. There are variety of swimming postures with all having diverse impact on reducing hydrodynamic drag. Intuitively, one can assume butterfly stroke, trudgen, backstroke, breaststroke, sidestroke, dog paddle and front crawl.

A comparative study is deemed significant to reach to a conclusion about the best swimming posture required for best swimming performance. Objective The major purpose of this lab report was to analyze the hydrodynamics of different swimming strokes through considering several factors such as swim time, stroke frequency, stroke length and perceived effort, in the comparison process. Results and data analysisSwimming pool length = 25 mA (when head is out of the water) Total time taken = 35 secondsRequired strokes to complete the distance = 50 strokes Average stroke frequency = 50 strokes/30.

01 seconds = 1.43 ≈ 1 stroke per secondsAverage stroke length = 50/25 = 2 stroke per meterB (when head is completely in inside the water)Total swim time = 20 secondsRequired strokes to complete the swimming pool length = 45 strokesAverage stroke frequency = 45/20 = 2.25 strokes per second ≈ 2 strokes per secondAverage stroke length = 45/25 = 1.8 strokes per meterC (dolphin kick)Swim time = 13.20 secondsD (dolphin with some parts) Swim time = 16.10 secondsDiscussion From the results, scenario B assumes a shorter swim time and higher stroke frequency than in the case of scenario A.

Further, the perceived effort used in B was less than that used in A. The reasons for the observed phenomena, depends on such factors like gravitational pull, friction force and outside pressure. When a swimmer is partially submerged, as shown in A, there is increase in atmospheric pressure and gravitational pull acting thereby resulting in reduced speed. Further, while partially submerged, some parts of the body remain exposed to the air thereby triggering action of friction force between swimmer’s body and air.

At the same time, scenario A allows the subject to breath, which in turn reduces the stroke frequency because more time is spent in breathing. The situation is different to scenario B, where swimmer’s body is fully submerged in water leading to reduction in friction force, gravitational pull and atmospheric pressure acting. This triggers shorter swim time, higher stroke frequency and less perceived effort (Stager & Tanner, 2005). The results also manifest differences between scenario C and D, where dolphin kick was used for both with difference being one is submerged while the other is not.

C, where full submergence was assumed, both swim time and perceived effort was less than D (not submerged. This can be attributed to the fact that dolphin kick becomes more effective when there is reduced friction and gravitational force through ensuring full submergence (Maglischo, 2003). The reduced forces leads to less perceived efforts and swim time as observed in scenario C. For situation D, more force is allowed to act on the swimmer in addition to efforts spent on breathing continually.

ConclusionThe experiment was successful in meeting the aforementioned objective because it gives a satisfying conclusion about the effect of hydrodynamic drag force on different swimming posture. The report illustrates that regardless of swimming position, the ability of a swimmer to reduce action of frictional force, gravitational force and atmospheric pressure determines impact of hydrodynamic force; consequently affecting speed and perceived efforts. In which case, submergence allows a swimmer to minimize the influence of the mentioned forces thereby leading to less swim time and perceived effort while swimming.

ReferencesMaglischo, E. W. (2003). Swimming fastest: [The essential reference on technique, training, and programm design]. Champaign, Ill. [u.a.: Human Kinetics. Stager, J. M. C., & Tanner, D. A. (2005). Swimming. Malden, Mass: Blackwell Science.