A recent study evaluated the effects of dynamic stretching and static stretching against a control group (no stretch) on explosive movement drills after a 24 hour delay (Haddad, 2014). They tested subjects’ on 5 different jump tests and on their repeated sprint ability. The findings suggest that static stretching done 24 hours before a maximum effort explosive movement (jump tests) can impair performance while the dynamic stretching group showed improvement in their jumping abilities.
NOTE: Static stretching consists of lengthening muscle(s) to end range of motion with a pause (usually 10 to 30 seconds). Dynamic stretching involves moving a joint/muscle through a normal to full range of motion without a pause.
According to another study, static stretching between bench press sets of 80% of 1RM performed to failure had no significant effect on performance (Ribeiro, 2013). The takeaway from both studies suggest that static stretching may potentially have a negative effect on maximal effort performance but has little to no effect on submaximal performance work.
If you plan to crush any strength PR’s in the next 24 hours, you should hold off on any static stretching today. This is not to say that static stretching doesn’t have its place in your program. If you need to improve your flexibility, static stretching may be useful but be mindful of when you use this technique. Plan on refraining from static stretching within at least 24 hours of any strength PR attempts. The first study did find that the group that performed dynamic stretching 24 hours prior to testing did notice an improvement in their jump performance. Based on these findings, dynamic stretching should be your primary source of stretching in at least the day before leading up to a PR attempt.
Haddad, M, Dridi, A, Chtara, M, Chaouachi, A, Wong, DP, Behm, D, and Chamari, K. Static stretching can impair explosive performance for at least 24 hours. J Strength Cond Res 28(1): 140–146, 2014
Ribeiro, Alex Silva; Romanzini, Marcelo; Dias, Douglas Fernando; Ohara, David; Pereira da Silva, Danilo Rodrigues; Júnior, Abdallah Achour; Avelar, Ademar; Cyrino, Edilson Serpeloni. Static Stretching and Performance in Multiple-Sets in the Bench Press Exercise. Journal of Strength & Conditioning Research: POST ACCEPTANCE, 25 September 2013