distal attachments during the stretch. The numerous studies comparing stretching techniques

show mixed results. For example, PNF stretching appeared more beneficial than the static stretch (22, 23, 24), whilst static, dynamic and PNF stretching all produced significant improvement in a study by Lucas and Koslow (25). However the studies have not always taken into account the effect of positioning, undertaking other activity and the variations in the total amount of time spent in a stretched position. Stretching to improve mobility should be done at the

end of training/competition when the performer is hot (sweating). Fitter athletes are more efficient at regulating body temperature, and may have to keep “topping up” their muscle temperature by further exercise as they change from one specific stretch to another. Alternatively, they could use artificial means to raise muscle temperature by practice a stretching regime after a warm/hot bath or shower. Stretching programmes must ensure that excessive

mobility in one area of the body is not compensating for poor mobility and/or lack of strength in another area eg excessive protraction of the left scapula compensating for limited trunk rotation during the backswing of right-handed golfers or increased lumbar-pelvic mobility compensating for limited hamstring flexibility in running sports. Improving joint or muscle mobility without strengthening in the new range of movement can create injury problems: n Ligaments can be strained as they try to protect a joint that is vulnerable due to lack of muscle strength in the new range

n Muscles can be strained when they are too weak to protect themselves in outer range

Flexibility training may vary according to the athlete’s training phase. Although microtrauma may occur when athletes stretch to increase range immediately after a high intensity training session, currently no research has been found to prove that this is a problem, particularly as the nature of training is overload, and hence microtrauma is to be expected. Providing the athletes are in training, rather than in competition, the benefits of stretching outweigh any potential risks. It is accepted that muscles will have an increased tendency to tighten as training volume and/or load increases. By stretching immediately after training it is easy to ensure that the amount of stretching meets the requirements at that time. Athletes may choose to work on increasing flexibility as a separate session but it is recommended that they increase their muscle temperature first. Discipline is required for mobility regimes and it may take several weeks to see an improvement. This means physiotherapists need to be discriminating: avoid designing inappropriate and ineffective exercise programmes and be aware that there are substantial

that

individual differences in response to stretching techniques.

WARM-UP The warm-up is not an appropriate time to try to improve 22

mobility. Athletes should only move joints and/or muscles through a range they are already capable of achieving. Trying to improve mobility during the warm-up is often counter- productive, with muscles feeling stiff and sore - the opposite of what the athlete hoped to achieve!

It is not recommended to statically stretch prior to competing or training where strength and/or power are required eg prior to weights. In fact, static stretching immediately prior to activity has been shown to reduce vaulting speed in gymnasts (26), to have a negative influence on explosive force and jumping performance (27) and to impair balance, reaction and movement time (28). Larsen et al (29) showed that a static stretching regime had no effect on joint position sense in healthy volunteers, whilst Ghaffarinejad et al (30) showed improved joint position sense in the knee following a static stretching regime for the quadriceps, hamstring and adductors in healthy subjects. Stretch-induced impairments have been reported to occur as early as 1 minute (28) continuing for 120 minutes post- stretching (31).

Behm et al (32) investigated whether the stretch- induced impairments reported in the literature were a training-specific phenomenon; athletes with a high level of flexibility or tolerance to stretch might be better able to sustain the stress of an acute bout of stretching or that a musculotendinous unit with greater range, or that is more tolerant to stretch, might accommodate the stresses associated with an acute bout of stretching more successfully. Their results showed that an individual’s initial level of joint ROM was not correlated with the stretch- induced deficits and that four weeks of flexibility training did not reduce the stretch-induced impairments. They proposed that if individuals hold stretches to the point of personal discomfort, the relative stress will be similar with flexible or inflexible muscles.

Warm-up routines should be athlete and sport specific. Not all the hamstring exercises that are suitable for a sprinter will be suitable for rugby player. Certain elements of the warm-up will be relevant to every athlete, but there should also be sport/discipline/position specific elements to the warm-up.

Prior to training/competition, the warm-up routine should follow a set pattern, or at least use exercises/ routines with which the athlete is fully familiar. This enables the athlete to focus on the event without having to worry about which exercises to perform. The time to experiment with new warm-up routines is during training.

Many sports use dynamic warm-up in preparation for training/competition. Dynamic warm-up tends to follow a similar pattern and should use the sport’s patterns of movement: n Easy aerobic work eg walking, striding, bounding, skipping and jogging, all performed at low

intensity n As the warm-up session progresses, the exercises move to a higher intensity

n Non-sport-specific full range (“normal”) movement of relevant muscles and joints e.g. arm circling, leg swinging, rotating the whole body whilst standing - without moving

sportEX medicine 2008;37(Jul):20-23