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Claxton, J., Cronin, J., and Bressel, E. (2005). Pre-event preparation routine-part two:
The effect of stretching on athletic performance. Strength and Conditioning Coach,
13(3), 2-5.
PRE-EVENT PREPARATION: STRETCHING FOR STRENGTH AND POWER
PERFORMANCE
Johnny Claxton1, John Cronin1 and Eadric Bressel2
1New Zealand Institute of Sport and Recreation Research
Auckland University of Technology
Private Bag 92006
Auckland 1020
johnny.claxton@aut.ac.nz
2Biomechanics Laboratory, Utah State University, Logan, UT, 84322, USA
Abstract
Most pre-event preparation routines usually consist of both aerobic activity and specific
stretching exercise, the related literature often refers to this period as a single entity,
known simply as ‘the warm-up’. It was argued in the previous article that light aerobic
activity and stretching serve two very different purposes and hence the effects of these
two components on pre-event preparation would be discussed separately. The objective
of this paper is to examine the stretching component of the pre-event preparation period
in terms of performance enhancement. It is hoped that the reader arrives at an
understanding of how stretching affects muscular performance and how we may better
structure the pre-event preparation period to the individual needs of the athlete, sport and
environment. Please note that this treatise will not examine aspects of injury prevention
as this topic was thought to be beyond the scope of the current paper.
PRE-EVENT STRETCHING
Introduction
Most athletes regularly undertake some form of stretching exercise as part of their preevent preparation routine prior to participation in more intense physical activity. The
foundation for this practice appears based on the perception that the stretching exercise
will augment joint range of motion (ROM) and compliance, which have traditionally
been considered significant factors in athletic performance. Although there are a number
of different stretching methods, the majority of related research has focused on the
technique known as ‘static stretching.’ Static stretching involves the passive extension
and static hold of the target muscle at a particular length, and appears to be the most
popular method of stretching amongst both athletes and physical therapists. Reasons for
the popularity of static stretching are its simplicity of execution, proposed lower risk of
injury compared to the other methods (e.g. ballistic stretching) and it’s ability to improve
extensibility of the musculotendinous unit (McNair & Stanley, 1996; Taylor et al., 1990;
Willy et al., 2001).
An alternative method of stretching, known as ‘dynamic stretching’ is also prevalent in
several power-orientated sports, such as track and field athletics and weightlifting.
Dynamic stretching is characterised by the performance of a variety of progressively
intensive limb motions, such as leg and arm swings. These movements gradually
increase the ROM that a limb or body part is moving through to a point where the ROM
is similar to that likely to be encountered during competition, thus producing a dynamic
or active stretch of the involved musculature. Due to the active contraction-relaxation
process associated with these activities, proponents of dynamic stretching advocate this
particular preparation technique as a more sport-specific method for increasing muscle
temperature and thus, a more appropriate form of pre-event stretching, especially for
events in which rate of force development (RFD) or speed of movement is considered a
determinant of success. However, there is a paucity of research pertaining to the
performance effects of dynamic stretching activities, with present support for this
technique based on anecdotal evidence. The aim of the following section is to examine
the existing literature pertaining to the effects of pre-event stretching on specific
performance tasks involving strength and power. The effects of pre-event, or acute
stretching, on endurance performances have not been formally examined and therefore
will not be considered in the following section.
Strength performance
Pre-event static stretching has been shown to have a detrimental effect on a number of
different measures of strength performance. Fowles et al. (2000) have indicated that
maximal isometric strength was significantly decreased (28%) after a bout of maximally
tolerable passive stretch and the decrement in torque was still evident 60 minutes after
stretching, albeit to a lesser degree (9%). Avela et al. (1999) reported a decrease (23.2%)
in maximal isometric strength using an intervention very similar to the study of Fowles et
al. (2000).
In addition to isometric strength measures, Kokkonen et al. (1998) have also reported that
a 20 min regime of maximally tolerable static stretching significantly reduced (7.3%)
one-repetition maximum (1RM) concentric strength performance. While the results
presented by Avela et al. (1999), Fowles et al. (2000) and Kokkonen et al. (1998) suggest
that stretching appears to have a detrimental effect on isometric or slow velocity strength
performance, these particular findings may only have limited application in the athletic
context due to the methodologies employed. For example, not only do the stretching
durations (20-60 min) substantially exceed those currently performed by athletes in the
field, but also most athletic movements are dynamic, as opposed to static, in nature. As
such, more pertinent information may be gained from studies involving relevant sportspecific stretching protocols and movement speeds.
Nelson et al. (2001) have examined the effect of static muscle stretching at a variety of
movement velocities. The most significant finding from this study was that the greatest
decrease in maximal voluntary force (7.2% and 4.5%) was observed at the two slowest
velocities, with no differences observed at the faster movement velocities. It may be that
the inhibitory effect of static stretching activities on maximal force production might be
limited to isometric muscle actions or movements performed at relatively slow joint angle
velocities.
Nelson and Kokkonen (2001) examined whether stretching of a ballistic nature would
induce similar strength impairments to those observed by Kokkonen et al. (1998)
following static stretching. The ballistic stretching protocol involved subjects assuming
positions identical to the static positions outlined by Kokkonen et al. (1998), however,
participants were then instructed to undertake 15 seconds of short-range ‘bobbing.’ It
was observed that ballistic stretching significantly decreased 1RM performance for both
knee extension (5.6%) and flexion (7.5%). It was concluded that both static and ballistic
stretching protocols could negatively affect force production.
Power performance
There have only been a small number of studies that have examined the acute effect of
stretching on power production, with the majority focusing on some form of vertical
jump test. Church et al. (2001) have investigated the effects of both static and
proprioceptive neuromuscular facilitation (PNF) stretching techniques on vertical jump
performance following a five-minute warm-up that consisted of a series of general body
weight exercises. While it was observed that both static stretching (1.3%) and PNF
stretching (3.1%) caused a reduction in jump height compared to warm-up only, the PNF
result was the only measure that was statistically different (P<0.05). Similarly, Cornwell
et al. (2001) have also reported an impairment in jump performance following assisted
static stretching causing a decrease in both concentric only squat jump (-4.4%) and
counter-movement jump (-4.3%) performance.
Young and Elliott (2001) have also investigated the effects of static stretching and PNF
stretching on vertical jump performance with interesting results. This particular
investigation involved subjects performing an initial five-minute jogging warm-up,
followed by a protocol totaling three minutes of either static stretching, PNF stretching,
isometric MVC, or control (no treatment). Immediately following the intervention,
participants undertook a rest interval that comprised four minutes of slow walking. At
the completion of this procedure, concentric only squat jump and 30-cm drop jump
performance were assessed. Although a trend was observed for all interventions to
decrease both squat and drop jump performance compared to the control group, only the
effect of static stretching on drop jump (7.0%) was found to be statistically significant
(P<0.05). These authors suggested that the effect of the initial jogging warm-up may
have ‘diluted’ the magnitude of the effects observed, and it was speculated that in the
absence of warm-up, the negative effects of stretching might have been more
pronounced. This assumption was based on the findings of Rosenbaum & Hennig,
(1995) who reported that while three minutes of static stretching reduced peak force
(5%), the addition of 10 minutes of jogging caused results to return to baseline measures.
Conclusions
Static muscle stretching has long been included in the pre-event preparation routines of
both social and competitive athletes. The foundation for this practice appears based on
the ability of passive stretching techniques to augment musculotendinous extensibility,
which has traditionally been considered a beneficial factor in athletic performance.
Despite its prevalence, static stretching prior to athletic activity may be detrimental to
performance measured in terms of muscular force and power output. This is in conflict to
the common belief within the sporting community that pre-event stretching improves
performance. However, we must be careful at making conclusions as to the efficacy of
static stretching, as most research in this area has studied the effects of single expressions
of force and power e.g. maximal lift, vertical jump, etc. There has been a distinct lack of
research into the influence of pre-event stretching on longer duration events, especially
those involving intermittent periods of high-intensity exercise (e.g. team sports). With
regards to pre-event stretching, investigations involving more relevant stretching and
performance measures would seem required, with alternative stretching techniques such
as dynamic stretching warranting further examination. Finally, the time-course of
performance effects are also relatively undefined, as such, investigation into the duration
of any performance modification following both pre-event warm-up and/or stretching
activity is necessary.