ترجمة

Saturday, July 18, 2020

12:06 AM

Importance Of Streamline



In the beginning, it's a good study to end the argument about the streamline head position as for so many years the coaches asked there swimmers to tight there streamline and some of them highlight the head position must be in the middle and the need to squees their arms against the ears and the others highlighted Michele Phelps Hyperd streamline we the head down before we discuss this study we need to explain what is The term “passive drag” relates to the hydrodynamic resistance forces that occur when a swimmer remains in a stable position and is not moving any part of the body. 


this study has been done on A total of ten male swimmers (age: 21 ± 2 years; body height: 1.80 ± 0.06 m; body mass: 75.9 ± 6.9 kg) participated in this study after giving their informed consent. All of the swimmers were regional-level and had at least 10 years of competitive swimming experience. The investigation was performed during the winter of 2014 when the swimmers were in the competition period.

Results:

Regarding the swimmer’s head position, passive drag was found to be significantly lower in with the arms in front of the head for the Head Down and Head in Middle than the Head-Up at all speeds. No differences were observed in passive drag between the Head Down and Head in Middle at all speeds. The statistical analysis revealed that with the arms alongside the body (arm down), the significant highest values of passive drag were only in the Head-Up rather than in the Head Down at the two fastest speeds (1.7 and 1.9 m/s). However, the pairwise comparison showed no significant differences for the Head in Middle rather than for the Head-Up and Head Down at all speeds. 


The results show a reduction of 4–5.2% in average passive drag when the head was down or aligned with the swimmer’s arms alongside the body(Arm down), in comparison to the head-up position. There was a major decrease of 10.4–10.9% in passive drag when the head was down or aligned with the swimmer’s arms above the swimmer’s head (in streamline position). it shows in the graph with the yellow dot.

Conclusion:

Regarding to this study and the related studies the in passive drag position, the streamline with the head down is less drag by 10.4 - 10.9% but also we have to mention that in the speed of 1.9 the streamlined with the head down and the head between the arms almost equal. we have to focus on the streamline in our day to day workouts. And don't forget that 30% of all the races are on the walls for start and turns and the streamline is a valuable key to success in that we need to use and develop.

References:

Cortesi, M., & Gatta, G. (2015). Effect of The Swimmer’s Head Position on Passive Drag. Journal of Human Kinetics, 49, 37 - 45.

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Saturday, July 11, 2020

11:42 PM

RAISING A SUCCESSFUL KID IN SWIMMING



By: C.Moemen Arafa
Today we will discuss a few pieces of Advice for young children to be successful in swimming or any other sports. First of all, in my belief as a coach, the parents have More Control on their Kids more than us and with few tips that we will discuss in this article will help you to understand More About Sport, especially Swimming.
you need to know that building a successful Swimmer or an Athlete in Any Sport Takes time. so Accept that progress in any sport takes at least 7 -10 years after puberty in most sports for any athlete to achieve their full potential.

Tuesday, May 19, 2020

11:12 AM

The Effect of Detaining on Swimmers


After five months of intense training, a study of eight male swimmers was conducted within four weeks of no training. The performance time was not affected. However, the losses in training aspects during that period were:

  • Muscle glycogen decreased from 153 to 93 mm / kg;
  • High blood lactate level from 4.2 mm / l to 9.7 mm / l. After swimming 200 yards, 90% of the best time
After only one week, a decrease in the oxidative potential of swimmers' muscles and a greater disturbance of acid-base balance in the blood after swimming is observed. The study also showed that complete conditioning may be completely lost within six to eight weeks after stopping training. What has been gained from conditioning in 5 months can be lost in a period of 6 to 8 weeks, and factors of loss of adaptation appear in the first week to 4 weeks, which is a short period.

Thursday, June 14, 2018

9:13 PM

The Effect of Cold Water Immersion On Recovery



Today we will talk about the CWI (cold water immersion) therapy recently it becomes one of the popular recovery protocol in swimming field. Before I talked more about the CWI let me give a small introduction about the recovery.

 Recovery is one of the most important things in training, it used to minimize the risk of overtraining, injuries and it boost the enhancement process for the muscles tissues. And it becomes so important during the hard training or competition to sustain an optimal state of performance (Mair SD, Seaber AV, Glisson RR, Garrett WE 1996).

Consequently, we came up with many recovery protocols like massage therapy, foam rolling, compression garments, hyperbaric oxygen therapy, electrical stimulation, whole-body vibration and water immersion therapy (including: cold water, warm water, and contrast bathing).

When I planned to write in this topic I found out many mixing opinions and studies about the effect of CWI therapy for recovery in general and more specific studies about swimming, in my opinion, we need more specific studies in this topic to proof the effect of CWI therapy.

Cold water immersion (CWI), otherwise known as ice-baths, plunges pools and cold water therapy is a recovery process involving the immersion of the body into cold water (≤15˚C/59˚F) immediately after exercise in an attempt to enhance the recovery process (Bleakley, C., McDonough, S., Gardner, E., Baxter, G.D., Hopkins, J.T., & Davison, G.W. 2012).

In a study for Hohenauer E, Taeymans J, Baeyens J-P, Clarys P, Clijsen R (2015) on The Effect of Post-Exercise Cryotherapy on Recovery, in this study they test the effectiveness of CWI by measuring different factors:

Tuesday, June 12, 2018

5:35 PM

Swimming and Flu



Swimming and Flu

Research has shown that those who practice swimming moderately are less susceptible to influenza than the average person and also swimmers who perform a really hard training are vulnerable to the flu, such as those who do not swim because of the length and strength of the workout that leads to reducing the efficiency of some immune functions for a period of a few hours to a few days. This gives the opportunity for viruses to invade the body. While this is not directly related to the performance of the circulatory system and metabolic processes and muscle performance, but the immune system is very important for every swimmer when there is a weakness in it the swimmer is vulnerable to the flu and when the swimmer is sick he will be unable to perform, training and competition optimally. Fortunately, however, there are many measures that can be taken to significantly reduce body infection must be done as a habit. The immune system depends heavily on nutrition. The best swimmers in the world know that there is moderate nutrition and no swimmer in life reached high levels without eating large amounts of vegetables and fruits and a balanced diet that provides the necessary support for the immune system. Sleep is also important to support the immune system.