Static vs. Dynamic Stretching in Football

Article extracted from www.footballscience.net

Before we start to elaborate on stretching we would like to present a tiny shocker from Thacker et al. 2004 who stated that “there is not sufficient evidence to endorse or discontinue routine stretching before or after exercise to prevent injury among competitive or recreational athletes”. However, the authors furthermore stated that “further research, especially well-conducted randomized controlled trials, is urgently needed to determine the proper role of stretching in sports”. As a result, if you don’t want to incorporate stretching, don’t believe in it or just don’t feel you have the time - stop reading here.

The following paragraphs will provide further knowledge on the different types of stretching, especially with regard to duration and frequency and the last paragraph will provide possible solutions to incorporate different stretching types into football schedules.

Different Types of Stretching

Static stretching

Static stretching is mostly performed as a passive stretch where the muscle is not active and is stretched by external forces. Usually this controlled stretch is hold for several seconds and it is perfectly suited to increase range of motion i.e. increase flexibility.

If increased range of motion is desirable then this type of stretching should be performed at least one to three times (3) a week and stretches held for at least 20-30 seconds (2, 8, 12). Static stretching might be more suited in football for post-activity (exercise/game). However, it can be used for warm-up with limitation as well. In this context the amount of repetition, number of sets and duration of stretching might be crucial (11) to ensure conservation of power and explosive force. There was an increase in range of motion after 30 seconds of static stretching, in addition, no loss of peak torque was observed in knee extensor muscles (13). However, a significant loss of force was observed after 10 (and 16) x 30 seconds static stretching (which to us is an impractical time duration of pre-match stretching for a single muscle(group)) (13).  From player’s perspective it sometimes also seemed “essential” to also incorporate static stretching as it is used as a mental preparation as well.

Dynamic stretching

If arms and legs are moved through its range of motion with a controlled speed, dynamic stretching is thought a safe type of stretching and should not be confused with ballistic stretching in which the movement through the range of motion is faster, nearly explosive and utilizes the so called stretch-reflex (SR) where MS and GTO are activated. As a result, dynamic stretching should be used for warm-ups and not necessarily for cool-down recovery.

The advantages of dynamic and ballistic stretching are that football specific movements (4, 5), for example a kick or jump are replicated. It seems that this type of stretching is more appropriate for the players’ preparation prior practices and games. However, caution must be taken as the speed of motion is crucial in injuries and therefore ballistic stretching is NOT suited for a cold and unprepared muscle that is present in an early stage of a warm-up.

Proprioceptive neuromuscular facilitation (PNF)

This method seems to be a good alternative to static stretching and is reported to be superior in improving range of motion (1, 6, 10). However, this type of stretch sometimes requires a partner and therefore is more complicated than regular static stretching. From a practical point of view, we believe that PNF-stretching is more suited in an extra session (especially) in pre- and in-season.

Stretching as Part of Game Preparation

With the information above in mind, it seems plausible to combine multiple stretches on game-day during warm-up and cool-down.

In the initial phase of the warm-up, where the muscles are still relatively cold, static stretching seems to be the most beneficial and safe way to enhance range of motion. As described earlier, a prolonged time needs to be present to change the muscle tone and therefore muscle length to receive some loss in force/power output. A stretch of 8-12 seconds (and up 30-60 seconds (9, 13)) could also be sufficient to improve range of motion without negative effects of extensive stretching, especially if some sort of jumping, bounding, sprinting, passing, shooting follows the stretch.

Generally, it is recommended to switch between sequences in the warm-up, which guarantees enough rest between exercises and therefore provides breaks to integrate stretching phases. During later stages in the warm-up, dynamic stretching should be the preferred choice, as the motion imitates football specific movements and therefore better prepares players for competition. Again it needs to be mentioned that caution needs to be taken regarding movement speed and the range of motion while stretching dynamically, as high velocity movements can cause muscle damage at end of range of motion (As a practical example: No player enters the pitch and start sprinting and finishing on goal right away). However, if the speed of movement and the range of motion are steadily increased throughout the dynamic stretches, there should be no harm and the preparation of the athlete should be optimal.

Ballistic stretching should be utilized last in a warm-up. Most of the time, it is part of high-explosive movements such as change of direction or finishing. As mentioned earlier, PNF stretching is best used in a separate training sessions for muscles that have been identified as problematic and need increased range of motion. If psychological preparation is needed (as previously mentioned) then a practical solution might be to use static stretching, however, coaches should pay attention to the exercise intensity afterwards, meaning, the intensity should be steadily increased including high-explosive movements at the end. As mentioned earlier, it is possible to incorporate static stretching.

Stretching in Adults vs. Youth

Generally, there is (even) less scientific evidence about when and how stretching might benefits youth, however, it seems plausible to include stretching (static and dynamic as mentioned in adults) in the warm-up and cooling down process around PHV as the youth have reached ~95% of their adult height at that point in time. In order to capitalize on stretching effects, adults and youth need to execute regular sessions. It is not enough to use stretching in/as a cool-down to expect changes in muscle length and to increase range of motion/flexibility. The purpose of stretching in a cool-down is seen as part of recovery for muscle functionality.