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Published: 30.09.2004, 06:00
Modified: 29.09.2004, 23:08
Stretching: useful or useless? Answers from the ASVZ
Bouncing and other exercises

One question has furnished the sports sciences with food for debate since the 1980s; namely, is stretching a worthwhile exercise or is it useless? The media reports dealing with this type of exercise usually mirror the discussion in abbreviated form–a recent headline reported: "Stretching exercises are out!" The articles underneath headlines like this one are often incomplete or simply wrong, say representatives from the ASVZ, and have produced their own brochure to draw attention to the benefits of stretching.

By Michael Breu

"Nearly everyone does it, and hardly anyone knows why," writes Kurt A. Moosburger, sports physician from Tyrol, in the "Newsdienst" of the Medical University of Innsbruck. The subject of the article in question is stretching. "The current situation in scientific research isn't easy to describe, because not all questions have been answered. But we can refute a few myths," writes Moosburger. Misunderstandings arise mostly from the lacking definition of the term "stretching". Not everyone understands the word in the same way. Some still take it to mean what it meant fifty years ago, when it was first defined as a dynamic stretch exercise that is executed with lots of vim. "The 'in-thing' in those days was bouncing and gymnastic exercises that held out the promise of an active fitness“, says Sandra Bonacina, physiotherapist, sports instructor and lecturer at the ETH Institute of Human Movement Sciences and Sport, looking back to the 80s in her article in "Fitness Tribune“ (2002, 1: 86-89). It was during this decade that a new stretching wave changed the prevailing bouncing execrcises; bouncing was out, static stretching was in.

Stretching doesn't help to sore muscles

In the meantime researchers in biomechanics and sports science (1) have added to their expertise and refined their results. Nonetheless, there are still unanswered questions. "The only thing that has been scientifically proved up until now is that a muscle attains a greater joint reach if it is regularly stretched. All other effects are based more or less on conjectures that are deduced from this one result," says Thomas Jöllenbeck, sports scientist at the University of Wuppertal. Working together with Professor Klaus Wiemann, also of the University of Wuppertal. Jöllenbeck investigated the behaviour of the muscular system by looking at different types of stretching. "The results turn some previous suppositions upside down, because if stretching is done intensively it doesn't change the length of the muscle; it leads to an increase in the muscle tension in repose and increases the risk of injury." Another investigation, published in the German magazine, Sportmedizin (1995, 9:411-421) shows that muscle soreness cannot be prevented by static stretching and that stretching exercises carried out shortly before exercising actually increase–rather than reduce–aching muscles. It was only recently that an article, published two years ago in the British Medical Journal, hit the headlines in the Swiss media with soundbites like, "Useless stretching exercises are out“, (Pulstipp of May 2004). The research, on which the BJM article was based, was carried out at the School of Physiotherapy at the University of Sydney and came to the conclusion that stretching exercises did not lower the risk of injuries (of soldiers in military training) nor reduce the sore muscle condition of amateur athletes (BMJ, 2002, 325: 468-470). A similar investigation, published by a specialist magazine in January 2003, drew similar conclusions (Manual Therapy 2003, 8(3): 141-150). "It's a pity that the results of most research are based on static stretching and don't differentiate enough between the different techniques," thinks Sandra Bonacina.

Heiner Iten, sports instructor of the Academic Sports Association Zurich (ASVZ) (2), can only shake his head at such studies. "Of course stretching can't prevent sore muscles. A muscle doesn't become longer when it's stretched, either." The reason for this seeming contradiction is simple; sore muscles are the result of very fine muscles fibres being torn apart when the muscle is subjected to high levels of tension. And a muscle cannot be lengthened by stretching, its length is a fixed given. The versatility of joints, by the way, belongs to the same category and can only be minimally influenced.


continuemehr

Sports scientists recommend a stretching of the muscles after exercise. large

"What we can say with certainty is that stretching improves suppleness, that it's good for psychic relaxation before and after training, and that it can prevent injuries," says Iten. His explanation is plausible, "Stretching improves the elasticity of the muscles".

This is why, this summer, the ASVZ started a wide campaign on the theme of stretching, led by Sandra Bonacina and Heiner Iten and published a flyer with tips and tricks. In the flyer it says: "Stretching before any form of exercise prepares the joints, muscles, nerves and the vascular system for physical activity in an optimal way. Stretching after exercises relaxes the body and helps to regenerate more rapidly. Stretching in between awakens and increases the ability to concentrate, extends joints and muscles, stimulates blood circulation and prevents lopsided postures". And further on, "Stretching exercises improve the stretch tolerance of the muscle system, increase the radius of joint versatility, and help to prevent postural deformities." All these general statements, say Bonacina and Iten, are scientifically sound. "We know a lot more on the function of muscles today, like the balance of tension, for example," explains Sandra Bonacina. This deals with the interaction of bender and stretcher, of agonist and antagonist. To give an example: "Someone who sits at a desk all day long places a one-sided burden on their muscles. All muscles used for bending movements remain unchanged in their shortened state. Getting up and stretching the muscles relaxes them".

Scientifically proven

The majority of sports scientists agree with the information contained in ASVZ's flyer. "To start off with, stretching increases suppleness," said Jürgen Freiwald, biomechanics researcher at the University of Wuppertal and author of a number of specialist books on the subject of stretching (his latest book "The New Stretching – Facts, Legends, Practice“ is shortly to be published in Rowohlt-Verlag) in a recently aired TV interview on the ZDF channel. Finally, the sports medical specialist, Walter O. Frey from Zurich, said in the Pulstipp interview: "We can't do without stretching if we want to remain physically supple and versatile".


Tips and tricks

(mib) "Apart from endurance and strength, physical suppleness is an absolute must when it comes to training and sport. Versatility and strength combined with good perception are the best protection for joints and the muscular system", it says in the latest flyer, "Stretching", from the Academic Sports Association Zurich (ASVZ). The brochure also shows eight basic exercises, which help to stretch and mobilise the most important parts of the body, such as neck muscles, chest and buttock muscles, and those of the hips, thighs, upper and lower leg. Five further exercises are aimed at the muscle systems in the torso, hips, upper and lower legs. All 14 stretching exercises in the flyer can be carried out indoors (i.e., in a gym), as well as outdoors (on the grass or in the woods) or they can be done in the office. The flyer is an excellent complement to last year's brochure on the subject of "strengthening". "Stretching“ is available from the ASVZ .




Footnotes:
(1) Institut für Bewegungs- und Sportwissenschaften der ETH Zürich: www.ibsw.ethz.ch/
(2) Akademischen Sportverband Zürich: http://www.asvz.ch



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