TY  - JOUR
A1  - Behm, David G.
A1  - Alizadeh, Shahab
A1  - Drury, Ben
A1  - Granacher, Urs
A1  - Moran, Jason
T1  - Non-local acute stretching effects on strength performance in healthy young adults
T2  - European journal of applied physiology
N2  - Background
Static stretching (SS) can impair performance and increase range of motion of a non-exercised or non-stretched muscle, respectively. An underdeveloped research area is the effect of unilateral stretching on non-local force output. 

Objective
The objective of this review was to describe the effects of unilateral SS on contralateral, non-stretched, muscle force and identify gaps in the literature. 

Methods
A systematic literature search following preferred reporting items for systematic review and meta-analyses Protocols guidelines was performed according to prescribed inclusion and exclusion criteria. Weighted means and ranges highlighted the non-local force output response to unilateral stretching. The physiotherapy evidence database scale was used to assess study risk of bias and methodological quality.

Results
Unilateral stretching protocols from six studies involved 6.3 +/- 2 repetitions of 36.3 +/- 7.4 s with 19.3 +/- 5.7 s recovery between stretches. The mean stretch-induced force deficits exhibited small magnitude effect sizes for both the stretched (-6.7 +/- 7.1%, d = -0.35: 0.01 to -1.8) and contralateral, non-stretched, muscles (-4.0 +/- 4.9%, d = , 0.22: 0.08 to 1.1). Control measures exhibited trivial deficits.

Conclusion
The limited literature examining non-local effects of prolonged SS revealed that both the stretched and contralateral, non-stretched, limbs of young adults demonstrate small magnitude force deficits. However, the frequency of studies with these effects were similar with three measures demonstrating deficits, and four measures showing trivial changes. These results highlight the possible global (non-local) effects of prolonged SS. Further research should investigate effects of lower intensity stretching, upper versus lower body stretching, different age groups, incorporate full warm-ups, and identify predominant mechanisms among others.
KW  - Flexibility
KW  - Power
KW  - Crossover
KW  - Fatigue
KW  - Mental fatigue
KW  - Neural inhibition
Y1  - 2021
UR  - https://publishup.uni-potsdam.de/frontdoor/index/index/docId/63979
SN  - 1439-6319
SN  - 1439-6327
VL  - 121
IS  - 6
SP  - 1517
EP  - 1529
PB  - Springer
CY  - Berlin ; Heidelberg
ER  -