The Stretching Debate

By Diana L. Thompson
[Somatic Research]

A colleague recently recounted a research article she had just read on stretching. “It says stretching is bad for you!” She admitted that she had just scanned the abstract, but was quite dismayed nonetheless. As a massage therapist and yoga enthusiast, she incorporates stretching on the massage table and sends clients off with stretching homework.

The study she referred to investigated the results of 20 minutes of stretching prior to athletic competition.1 Participants who received the stretching protocol, along with a warm-up, performed worse on average than the control group (warm-up with no stretching). On its own, the study seemingly dismantled her beliefs on the benefits of stretching, grounded in 25 years of experience.

As luck would have it, the subject came up at this year’s Thera-Band Research Advisory Committee (TRAC) meeting.2 After two days of research presentations centered on increasing strength through progressive resistance training, the subject shifted to stretching. David Behm, PhD, associate director of Graduate Studies and Research in the School of Human Kinetics and Recreation at Memorial University of Newfoundland, gave an overview of nearly 100 articles reporting the effects of stretching on performance. With a staggering number of studies, some with more than 100 citations, the picture became clearer: static stretching improves static range of motion (ROM) and dynamic stretching improves action.

Now that we know the answer, let’s ask the questions: What are static stretching and dynamic stretching and how are they different? How could stretching be bad for you when it feels so good? What does this have to do with my somatic practice?

To Stretch or
Not to Stretch

The controversy surrounding stretching is not new. Those in sports and physical medicine have been weighing the evidence on stretching since the 1980s. As a result of decades of debate, the research hypotheses that define the investigations on stretching have been refined, as have the measurement tools. The current information addresses specific classifications of activities using detailed outcome measures, and can tell us when and how to stretch. We have reproducible evidence that delineates the different effects of stretching on elite athletes performing high-powered feats versus those who require improved range of movement to perform basic activities of daily living. That said, the debate continues.

While most of our clients are not competitive athletes, some of us specialize in serving the elite sports population. It behooves us to evaluate the evidence that pertains to our clientele. First, let’s look at the different types of stretching and identify which to apply to different populations to provide maximum results.

Static vs. Dynamic Stretching

The goal of stretching, regardless of style, is to increase ROM. Static stretching achieves this goal through a slow and constant elongation of a muscle or groups of muscles and connective tissue, commonly held for 30–90 seconds. Typically, the muscles are held in a relaxed position at the end range of passive or active motion—to the point of discomfort but not pain—without moving. A gradual deepening of the stretch every 30 seconds may be incorporated until maximum length has been achieved. Time is an important component: common theory states that holding the position for 30 seconds or more is less likely to injure the soft tissue.

Static stretching has been found to be effective for increasing ROM.3  Increased ROM has been shown to enhance movement and reduce injury.4 Static stretching has also been shown to reduce force, torque, vertical jump, and power in elite athletes when performed within 60 minutes of competition.5 After 60 minutes, the negative effects of stretching have diminished considerably, but a more recent study found stretch-induced impairments two hours after stretching.6

Dynamic stretching is a type of stretching done while moving. The goal of increasing ROM is similar to that with static stretching, but its emphasis is on enhancing action versus increasing passive ROM. This is achieved through quickly moving a limb to its limits using activities that mimic the actions of performance. There is no bouncing with dynamic stretching, as with ballistic stretching, nor is there an aggressive push beyond normal passive or active ROM. Movement into the stretch is gentle, though may incorporate a slightly explosive acceleration (as in martial arts kicking warm-ups). The stretches are typically held for 1–2 seconds, or as long as 15 seconds, before moving out of the stretch position. These stretching actions are repeated many times during a designated 1–2 minute period.

Dynamic stretching has been shown to increase vertical jump, speed, and power, and also enhance balance.7 There is substantial evidence demonstrating that dynamic stretching increases ROM without decreasing speed, power, or balance as with static stretching.8

A few physiological differences between static and dynamic stretching have been identified:

• Static stretching may drop core body temperature, while dynamic stretching can raise it.9

• Dynamic stretching increases heart rate, which may have an effect on blood flow to the area of concentrated lengthening, whereas static stretching may have an ischemic effect.10

• Dynamic stretching is linked to greater nervous system activation, shown by increases in electromyography (EMG).11

Dynamic stretching is therefore preferred over static stretching prior to peak performance because of the more specific gains in functional movement, coupled with an increase in heart rate, a rise in body temperature, and a stimulation of the nervous system specific to the actions the athlete will perform. All of this can be achieved without the reduction in speed, power, and torque that is associated with static stretching.

Static stretching is not contraindicated for all athletes. Static stretching may have a local ischemic effect in the moment of applying the stretch, but it does not diminish athletes’ high-intensity aerobic performance—in other words, static stretching does not affect endurance—nor does it affect running economy.12 In sports where power and speed are not primary, and in sports involving throwing and eccentric contractions like bench press, static stretching has no deleterious effect.13

Static stretching is still recommended routinely for athletes post-performance and during workouts away from performance. Static stretching is especially beneficial for postoperative patients, active middle-aged adults, and older adults with osteoarthritis, improving flexibility, enhancing activities of daily living (ADL), and reducing the impact of injury and illness on physical condition.14

Behm offered an analogy to explain the varying needs of the two populations—elite athletes and non-athletes—using car suspension: he likened elite athletes with Ferraris, requiring a very tight suspension to better enable them to respond quickly and take corners with precision. The rest of us prefer the loose suspension of a Cadillac—a car we can take on bumpy roads and enjoy the ride in comfort. In other words, if the tendinous attachments are too loose, it takes too long for the muscle to engage, decreasing the body’s ability to respond quickly and with great power. On the other hand, with an expanded sense of length, we are free to move in a myriad of directions, even change our minds midstream, and not risk feeling the bumps, bruises, or potential tears of going outside our normal ROM.

Some highlights of the data against static stretching pre-competition include:

• High-level athletes need tension; therefore, no static stretching before peak performance.15

• The longer the individual static stretch, the higher the impairment on performance.16

• Static stretching sessions ranging from 4.5 minutes to 30 minutes all decreased force, torque, and power, for example, in vertical jumps, for up to 60 minutes prior to performance.17

Implications on Somatic Practices

For those somatic therapists working with elite athletes immediately prior to competition, it may be important to avoid techniques that potentially mimic static stretching and use techniques that replicate dynamic stretching.

In a recent study, massage on the hamstring’s musculotendinous junction was found to improve ROM but had no effect on EMG, concluding that musculotendinous massage may be used as an alternative or a complement to static stretching for increasing ROM.18 While no study has been conducted on the effects of this type of massage on elite athletes prior to competition, it might serve as a warning—avoid concentrated massage directly on the attachments pre-event.

Aaron Mattes and his method of Active Isolated Stretching (AIS) incorporate all aspects of dynamic stretching: repetitive active-assisted stretches in the functional ROM, holding the stretches for no more than 2 seconds. It would appear that this very style of massage-assisted stretching is perfect for pre-event athletic warm-ups, for both the elite and non-elite athletes.19

Research on the use of resistive techniques to improve ROM, such as muscle energy technique (MET) or proprioceptive neuromuscular facilitation (PNF), have not been conclusive. While these techniques have demonstrated improvements in ROM equal to that of static stretching, some studies have shown that PNF has no effect on jump force20 and may have a negative effect on muscular endurance performance.21 The studies showing positive effects of PNF in combination with dynamic stretching prior to competition are cautionary, emphasizing the need for sufficient rest following warm-up.22 For now, it may be best to treat resistive techniques similarly to static stretching.

Other Implications

Let’s shift the focus away from athletes to look at what the research tells us about people with health conditions— particularly conditions that affect quality of movement—and see where there are benefits with stretching:

• In a study comparing older adults with and without osteoarthritis, both populations were able to demonstrate beneficial adaptations to a static stretching intervention.23

• Trigger point therapy, in conjunction with PNF stretching, has been shown to increase ROM and reduce pain in males with tight hamstrings and latent trigger points.24

• Active stretching, passive stretching, and PNF were all found to increase ROM in knee flexion of patients after total knee replacement.25

• Active-assisted stretching improved functional performance, mobility, power, and ROM in elderly persons with insufficient physical reserves to perform higher-intensity exercise.26

• Stretching, along with muscular resistance, breathing, and relaxation exercises, improved ROM and reduced the impact of the illness in women with fibromyalgia.27

Applicability

I find it difficult to think of a client who couldn’t benefit from enhanced ROM. When incorporating stretching into our practices, keep in mind the population and the intent: if full use of power, speed, and torque is required shortly after the session, avoid the use of static stretching, tendon-focused massage, and resistive stretching techniques. If rehabilitation, quality of life, and an overall sense of wellness are the priority, apply massage and stretching techniques that safely elongate the targeted muscles.

And remember, when consuming research, do not draw broad conclusions from one study. It is important to read the body of evidence and critique its protocol, power, and application to your clientele.

 A licensed massage practitioner since 1984, Diana Thompson has created a varied and interesting career out of massage: from specializing in pre- and postsurgical lymph drainage to teaching, writing, consulting, and volunteering. Her consulting includes assisting insurance carriers on integrating massage into insurance plans and educating researchers on massage therapy theory and practice to ensure research projects and protocols are designed to match how we practice. Contact her at soapsage@comcast.net.

Notes

1. J. R. Fowles et al., “Reduced Strength After Passive Stretch of Human Plantar Flexors,” Journal of Applied Physiology 89 (2000): 1179–88.

2. Thera-Band Research Advisory Committee, accessed September 2010,   

3. C. H. Chen et al., “Effects of Flexibility Training On Eccentric Exercise-Induced Muscle Damage,” Medicine & Science in Sports & Exercise (August 2, 2010).

4. Ibid.

5. D. G. Behm et al., “Factors Affecting Force Loss With Prolonged Stretching,” Canadian Journal of Applied Physiology 26, no. 3 (2001): 262–72.

6. K. Power et al., “An Acute Bout of Static Stretching: Effects on Force and Jumping Performance,” Medicine & Science in Sports & Exercise (March 2004): 1389–96.

7. Behm, “Prolonged Stretching,” 262–72.

8. I. M. Fletcher, “The Effect of Different Dynamic Stretch Velocities on Jump Performance,” European Journal of Applied Physiology 109, no. 3 (June 2010): 491–8.

9. I. M. Fletcher et al, “An Investigation Into the Possible Physiological Mechanisms Associated with Changes in Performance Related to Acute Responses to Different Preactivity Stretch Modalities,” Canadian Journal of Applied Physiology 35, no. 1 (February 2010): 27–34.

10. K. K. McCully, “The Influence of Passive Stretch on Muscle Oxygen Saturation” Advances in Experimental Medicine and Biology 662 (2010): 317–22.

11. I. M. Fletcher, “Preactivity Stretch Modalities,” 27–34.

12. F. A. Samogin Lopez et al., “Is Acute Static Stretching Able to Reduce the Time to Exhaustion at Power Output Corresponding to Maximal Oxygen Uptake?” The Journal of Strength & Conditioning Research 24, no. 6 (June 2010): 1650–6.

13. T. K. Evetovich et al., “Interpreting Normalized and Nonnormalized Data after Acute Static Stretching in Athletes and Nonathletes,” The Journal of Strength & Conditioning Research 24, no. 8 (August 2010): 1988–94.

14. C. Ayan et al., “Health Education Home-Based Program in Females With Fibromyalgia: A Pilot Study,” Journal of Back and Musculoskeletal Rehabilitation 22, no. 2 (2009): 99–105; A. Hakkinen et al., “Muscle Strength and Range of Movement Deficits One Year After Hip Resurfacing Surgery Using Posterior Approach,” Disability & Rehabilitation 32, no. 6 (2010): 483–91.

15. Behm, “Prolonged Stretching,” 262-72.

16. Ibid.

17. Ibid.

18. S. Y. Huang et al., “Short-Duration Massage at the Hamstrings Musculotendinous Junction Induces Greater Range of Motion,” The Journal of Strength & Conditioning Research 24, no. 7 (July 2010): 1917–24.

19. From Aaron Mattes website, accessed September 2010, www.stretchingusa.com/aboutAIS.cfm.

20. B. Yuktasir et al., “Investigation Into the Long-Term Effects of Static and PNF Stretching Exercises on Range of Motion and Jump Performance,” Journal of Bodywork and Movement Therapies 13, no. 1 (January 2009): 11–21.

21. T. M. Gomes et al., “Acute Effects of Two Different Stretching Methods on Local Muscular Endurance Performance,” The Journal of Strength & Conditioning Research (July 17, 2010).

22. Z. D. Molacek et al., “Effects of Low- and High-Volume Stretching on Bench Press Performance in Collegiate Football Players,” The Journal of Strength & Conditioning Research 24, no. 3 (March 2010): 711–6.

23. D. A. Reid et al., “Effects of An Acute Hamstring Stretch in People With and Without Osteoarthritis of the Knee,” Physiotherapy 96, no. 1 (March 2010): 14–21.

24. A. Trampas et al., “Clinical Massage and Modified Proprioceptive Neuromuscular Facilitation Stretching in Males with Latent Myofascial Trigger Points,” Physical Therapy in Sport 11, no. 3 (August 2010): 91–98.

25. T. P. Chow et al., “Active, Passive and Proprioceptive Neuromuscular Facilitation Stretching are Comparable in Improving the Knee Flexion Range in People with Total Knee Replacement: A Randomized Controlled Trial,” Clinical Rehabilitation (August 4, 2010).

26. D. C. Stanziano et al., “The Effects of an Active-assisted Stretching Program on Functional Performance in Elderly Persons: A pilot study,” Journal of Clinical Interventions in Aging 4 (2009): 115–20.

27. Evetovich, “Normalized and Nonnormalized Data,” 1988–94.