The Cooper Institute

Founded in 1970 by the "Father of Aerobics"
Kenneth H. Cooper MD, MPH


Static stretching before a workout: the debate continues

Posted in
Live well

Monday, Jun 27, 2011

The controversy rages as scientists continue to study the effects of static stretching on strength and power output. In 2010, the American College of Sports Medicine1 suggested that static stretching be performed after rather than before activities where muscular strength, endurance, and power are important for performance. This was based on research studies available at that time. For a look at some of the earlier research check out our June 21, 2010 blog on The Effects of Low and High Volume Stretching on Bench Press Performance. Although there are a number of papers that report declines in activities requiring maximal muscle effort performed after static stretching, others do not. However, a recent paper published ahead of print in Medicine and Science in Sports and Exercise2 sheds new light on this controversy. 

This paper reviewed the many research studies published on the topic and selected only the papers which used rigorous scientific methods. Researchers found that only 106 of the 4,559 total studies published on the topic met appropriate scientific criteria set forth for inclusion in their study. Once they selected the best studies for review, researchers compared the studies to determine if there were any differences between them that may have contributed to the different conclusions about static stretching and performance. These factors included stretch duration, muscle groups tested, and the specific strength/power test used to evaluate performance (e.g., vertical jump vs. strength test). 

Researchers found that 50% of the studies which met their criteria reported significant reductions in strength/power after static stretching. After looking at the length of the static stretch, they found that nearly all the studies which used static stretches held for <30 seconds reported no significant reduction in power/strength performance afterwards. As the duration of stretch increased from 30-45 seconds, some of the studies showed decreases in performance. However, when static stretch duration increased to more than 45 seconds, reductions in performance were consistently reported. Researchers did not find any differences with regard to the specific muscle groups tested after static stretching. Also, power, strength, and speed movements were all negatively affected as stretch duration increased. 

The results of this comprehensive paper suggest that static stretches held less than 30 seconds do not appear to produce significant decreases in power, strength or speed. As the duration of the stretch increases to 60 seconds or longer, moderate declines in performance are more likely. Due to the fact that the studies published on static stretching used different stretch durations, muscle groups, and performance tests, the results are difficult to interpret. However, it appears that the longer the static stretch the greater the likelihood that power, speed or strength performances may decrease. 

My observation is that most individuals don’t hold static stretches for more than 30 seconds anyway. If they choose to do a static stretch for 30 seconds for a tight muscle group after completing an active warm-up, declines in performance would be unlikely. I personally like to do a brief (15-30 second) static stretch after my dynamic warm up for muscles that still feel tight prior to starting my resistance training workout. Share your personal experiences with static stretching and strength/power activities on our Facebook page. Worth noting, the same controversy exists regarding static stretching before activities like running which focus on muscular endurance rather than strength. More to come on this topic!

1American College of Sports Medicine. (2010). ACSM’s Guidelines for Exercise Testing and Prescription. Philadelphia, PA: Lippincott Williams & Wilkins. 2Kay, A.D. & A.J. Blazevich. (2011). Effect of Acute Static Stretch on Maximal Muscle Performance: A Systematic Review. Medicine and Science in Sports & Exercise. Published ahead of print. doi:10.1249/MSS.0b013e318225cb27