>> December 30, 2010
So what does it tell you? If you are a 10.00 sprinter, will you automatically run 9.90? Not that simple! You may have to look at myriad of factors. In fact, there are many variables in stretching such as the time under stretch, types of activity etc.
Dynamic stretching becomes increasingly studied when a study by Kokkonen and his colleagues in 1998 has stated that the long been used (preparation technique) static stretching is actually detrimental for athletic performance.
Let us do the definitions before going into more details. What is dynamic stretching? dynamic stretching involves the active or dynamic movements that are performed within the range of motion (ROM). It is performed by increasing the ROM gradually and there must be "deceleration" at the end of each (stretch) repetition. In other words, no jerking or bouncing actions in dynamic stretching. This is the part that distinguish between dynamic stretching and the ballistic stretching. Athletes may consider utilize the specific movement in sports (activities) during dynamic stretching in order to (better) prepare the muscles for the subsequent sports or activities.
In contrast, static stretching is a constant stretch held at an end point of ROM. This means that the stretching involves "hold" at the end of ROM (for each repetition) for a given time. Most athletes perform static stretching for 20 to 60 seconds per muscle group.
Static stretching is done by athletes in order to reduce injury. This argument however is so far not fully supported by scientific reports. Its just that the practice of static stretching became popular after the release of book entitled "stretching" by Bob Anderson in 1980. This book has an excellent record in the number of sale.
In one of our studies that we name “the effects of dynamic and static stretching on sprint performance in junior sprinters” (2009), we found similar results to those published studies. Specifically, there were 2.1% (30 metres) and 2.3% (40 metres) improvement (faster times) when the athletes performed the dynamic stretching.
Although with the such findings, there are still many athletes regardless of their levels who are not very comfortable to shift with a new technique of stretching (the dynamics). I’ve seen a Commonwealth champion and World class athletes performed either static stretching, passive-static stretching (with partner) or a combination of static and dynamic stretching to prepare for workouts and competitions.
|Dynamic Stretching called 'Scorpion' to stretch lower back muscles area|
So why do you have to consider dynamic stretching now instead of static stretching? There are many physiological reasons of course, but in this short article we try to discuss a few. Static stretching increase the compliance or gap in the tendon and muscles. This is especially when you hold the muscles being stretched for a long time. These increases (also termed as musculotendinous slackness) reduces the muscle stiffness that is important for smooth muscular contraction. The reduced muscle stiffness will actually affect the muscular contraction because of the delayed electromechanical process or specifically the transmission of forces. Thus, the muscles are not able to perform maximally.
Meanwhile, the improvement of sprint performance following the dynamic stretching is linked to its characteristics. Dynamic stretching mimics most of actions seen in the sprinting. This helps increase better coordination of the subsequent movements (sprinting). Apart from that, dynamic stretching increases core temperature to a greater extent than the static stretching. In contrast, static stretching will help to put you to sleep, that is actually important after your race or training so that you will have a better recovery. So have you got anything to say?
(1) Mark Kovacs (2010). Dynamic Stretching (the Revolutionary New Warm-up Method to Improve Power, Performance and Range of Motion).
(2) Fletcher and B. Jones (2004). The effect of different warm-up stretch protocols on 20 meter sprint performance in trained rugby union players.
(3) Arnold G. Nelson, Nicole M. Driscoll, Dennis K. Landin, Michael A. Young, & Irving C. Schexnayder (2005). Acute effects of passive muscle stretching on sprints performances.
Photos: copied from notarunner.com & flex4fitness.com