Compose a 5250 words essay on Edting PNF v Atatic Stretching. Needs to be plagiarism free!Download file to see previous pages... Straight leg raise and modified sit and reach flexibility measurements

Compose a 5250 words essay on Edting PNF v Atatic Stretching. Needs to be plagiarism free!

Download file to see previous pages...

Straight leg raise and modified sit and reach flexibility measurements were then taken once every week on the same day at the same time.

Results: Both static and PNF protocols used in the current investigation were seen as adequate in improving hamstring flexibility. However the PNF technique was shown to produce significantly greater effects than the static group, showing the PNF technique to be the most effective at increasing hamstring flexibility, although whether the changes were due to viscoelastic or neural properties cannot be concluded.

Flexibility isan important component in reducing the potential for injury, improving performance during physical activity and sport (Etnyre and Lee, 1988. McCullough, 1990. Taylor et al., 1997. Witvrouw et al., 2004).

The hamstring muscle group is susceptible to injury (Funk et al., 2001) during eccentric exercises such as sprinting or jumping, activities which are present in many sports (Kujala et al., 1997). Inadequate muscular flexibility has been cited as one possible cause (Sundquist, 1996. Funk et al., 2001).

Muscular flexibility has both mechanical and neurophysiologic components (McHugh et al., 1992). A theorized mechanism by which increases in flexibility and ROM are attained following stretching is the involvement of the viscoelastic properties of the muscle tendon junction (Taylor et al., 1990. Magnusson et al., 1996a. Taylor et al., 1997. Zito et al., 1997. Gribble et al., 1999. De Deyne, 2001), this being the mechanical component of muscular flexibility (McHugh et al., 1992).

Viscoelastic behaviour implies a combination of viscous and elastic properties (Sanjeevi, 1982. Taylor et al., 1990. Magnusson et al., 1996a). Elasticity implies that the length change, or deformation, in muscle is directly proportional to the applied force or load (Taylor et al., 1990. Magnusson et al., 1996a. Zito et al., 1997). Viscous properties are characterised as time dependant and rate change dependant, where the rate of deformation is directly proportional to the applied forces (Taylor et al., 1990. Magnusson et al., 1996a. Zito et al., 1997).

When a muscle is stretched and held at a constant length gradually there becomes a slow loss of tension, this is known as stress relaxation (Alter, 1996) while the lengthening that occurs when a constant force is applied i.e. a stretch, is known as creep (Alter, 1996). Hysteresis is the variation between the load deformation relationship of loading and unloading (Taylor et al., 1990. Burke et al., 2000), it possibly indicates the viscosity of the muscle.

The intramuscular connective tissue that imparts elasticity to muscle tendon, consists of a series elastic and parallel elastic component (Magnusson et al., 1996a. Burke et al., 2000. Youdas et al., 2003). The endomysium is an important elastic component. It transfers force from the contractile component to the tendon and bone in series (Alter, 1996. Magnusson et al., 1996a. Youdas et al., 2003). The perimysium is the principle parallel elastic component. It distributes stress evenly and prevent overstretching (Alter, 1996. Magnusson et al., 1996a. Youdas et al., 2003).