The acute effects of a warm-up including static or dynamic stretching on countermovement jump height, reaction time, and flexibility
Perrier ET, Pavol MJ, Hoffman MA. J Strength Cond Res. 2011 Jul;25(7):1925-31.
From an early age we've been taught that we should stretch before exercise in an effort to increase ROM and prevent injuries. While most of those pre-workout regimens were based in static stretching, we have seen more dynamic stretching being incorporated in warm-up programs. While stretching and ROM increases go hand in hand, something that hasn't been investigated is the effect of static (SS) and dynamic stretching (DS) on athletic performance during a series of countermovement jumps (CMJ). This begs the question: “Should our pre-practice and pre-game warm-up be structured differently in an effort best maximize performance?” Previous research has determined that the CMJ is an effective way to assess performance. The investigators also examined reaction time, due to its critical importance in completing athletic tasks, as well as, both hamstring and low-back flexibility. Based on previous studies, the investigators hypothesized 1) that a SS warm-up would decrease CMJ height, increase reaction time, while a DS warm-up would have improvements in CMJ and reaction time 2) that performance differences would be minimal at the end of several CMJs, suggesting that the participant would become more proficient at jumping as the trial progressed 3) that there would be no difference in hamstring flexibility between SS and DS. In this study 21 recreationally active college aged males were recruited to perform 10 CMJs after standardized warm-up under 3 different conditions (no stretch, SS, and DS). The SS regimen included 7 different stretches focusing on the lower body, each stretch was performed 2x30 seconds, while the DS regimen included 11 exercises performed at a jogging pace over an 18m distance. After completing the NS, SS, or the DS program (individually and on non-consecutive days), the subjects then performed a standardized sit-and-reach test to examine what effect the various warm-up routines would have on the participants' flexibility. Lastly, using a portable force plate and a visual stimulus the subjects performed 10 CMJs, each one minute apart. Reaction time and CMJ height was measured via GRFs generated after the onset of visual stimulus. The results demonstrated that: 1) mean CMJ height was significantly higher for the DS group when compared to NS or SS 2) Jump height was significantly lower for the later jumps (reps 8&9) than for earlier jumps (2&3) under all conditions 3) There was no effect on reaction time regardless of stretch type 4) There was a significant change in sit and reach scores for both SS and DS but no significant difference between SS and DS.
These results are interesting for several reasons. It may suggest that there is no longer a place for static stretching in our athlete’s warm-up routine if DS is providing better CMJ results and comparable amounts of flexibility. It seems DS encompasses all aspects of functionality with no negative effects on reaction time. The athlete could conceivably be more prepared physiologically to perform by implementing aerobic activity and sport specific DS to increase blood flow, flexibility, and priming the body for imminent sporting activity. Although static stretching may not be optimal immediately prior to activity, it may still be needed for injury prevention. Static stretching is effective at increasing ROM over time and can decrease the risk of several musculoskeletal injuries. What are your thoughts? How is your pre-practice/pre-game flexibility program structured, and would you consider making adjustments to it based upon this study? Should we begin to move away from static stretching or do you feel that there is still a place for it prior to activity?
Written by: Mark Rice
Reviewed by: Stephen Thomas
Perrier ET, Pavol MJ, & Hoffman MA (2011). The acute effects of a warm-up including static or dynamic stretching on countermovement jump height, reaction time, and flexibility. Journal of Strength and Conditioning Research, 25 (7), 1925-31 PMID: 21701282