Acute stretch perception alteration contributes to the success of the PNF "contract-relax" stretch.
BACKGROUND
Some researchers have suggested that an alteration of stretch perception could be responsible for the success of the contract-relax (CR) stretch, a stretch technique derived from proprioceptive neuromuscular facilitation (PNF).


OBJECTIVE
This study was conducted to determine if the alteration of the stretch perception is a possible explanation for the range of motion (ROM) gains of the CR stretch.


METHODS
Eighteen subjects performed two stretches in randomized order: the slow stretch and the CR stretch.


METHODS
The stretch intensity was controlled. The stretch force was measured and compared between the slow stretch and CR stretch.


RESULTS
There was a significant difference between the stretch force that could be applied in the PNF stretch (126.0 N) and the slow stretch (108.4 N); P = 0.00086. The average stretch tolerance progressively increased with successive trials from 120.6 N in the first trial to 132.4 N in the fourth trial.


CONCLUSIONS
The alteration of stretch perception plays a role in the success of the CR form of PNF stretching. At least four repetitions of the CR stretch are recommended to get the greatest ROM gain.
Mitchell
Ulrike H
UH
Department of Exercise Sciences, Brigham Young University, Provo, UT, USA.
Myrer
J William
JW
Hopkins
J Ty
JT
Hunter
Iain
I
Feland
J Brent
JB
Hilton
Sterling C
SC
D000328:Adult; D018592:Cross-Over Studies; D005260:Female; D006801:Humans; D007537:Isometric Contraction / Q000502:physiology; D035002:Lower Extremity / Q000502:physiology; D008297:Male; D053581:Muscle Strength Dynamometer; D052580:Muscle Stretching Exercises; D010147:Pain Measurement; D010465:Perception; D011897:Random Allocation; D016059:Range of Motion, Articular / Q000502:physiology; D012026:Reflex, Stretch / Q000502:physiology*