Stretching at work
ART Literature Review:
by Everett Johnson, DC, ART
Stretching at work.
Musculoskeletal disorders (MSD) are defined as injuries affecting the connective tissues of the body, such as muscles, nerves, tendons, joints, cartilage, or spinal discs. When these connective tissues are stretched beyond their limits or over-used by participating in a repetitive motion or maintaing an awkward posture, an injury may occur, such as a sprain, strain or tear. (BLS) The Bureau of Labor and Statistics reports that sprains and strains account for the highest frequency of all occupational injuries in the United States. MSD injuries can occur in any industry, but service-providing industries account for 69% of the cases recorded. (BLS)
There are several methods employed to try to reduce the frequency of MSD. Some methods proven to be effective are engineering the workstation to reduce ergonomic factors or rotating workers through a strenuous work station can reduce each workers exposure and risk for a MSD. However, each of these options requires a significant financial commitment. An alternative method that has been under a lot of investigation is the implementation of a stretching program by the employees. Stretching is a form of physical exercise in which a specific skeletal muscle is deliberately elongated to its fullest length in order to improve the muscle’s felt elasticity. Benefits of stretching may include increased flexibility, improved range of motion within joints, improved circulation, improved posture, and stress relief. (Choi) The following is a review of several pertinent studies documenting the results of stretching programs in the workplace as a means to reduce MSD.
In 2006, Trujillo and Zeng reported on a trial program performed by workers with heavy computer usage. The trial consisted of a computer program installed on their computer called “Stop and Stretch.” The stretches were limited to the hand and wrist with the goal to “help relax tense muscles, improve blood circulation, increase the person’s ROM and prevent cumulative trauma disorders.” A detailed description of the stretches performed, their frequency and duration, was not included. After one month, a survey was completed by nineteen of the participants. 53% of the participants reported having fewer overall symptoms and 100% found the program helpful. 63.3% of the participants felt the program increased their productivity. With respect to productivity, it is hard to say whether the stretching or extra rest breaks resulted in the perceived increase.
In a similar study, Saltzman reported using a computer program entitled “Stretch Break.” In this program, participants were guided through a 1-2 minute stretching routine after every 45 minutes of work. Again, a detailed listing of the stretching protocol, including description of the stretches performed and their duration, was not included. Effectiveness was evaluated by administering a series of attitudinal statements after 15 weeks. The author reported “computer operators who used this software program with its frequent short stretching breaks reported that it was effective in reducing stiffness and muscle ache associated with long hours at the keyboard.” Stress reduction, awareness of ergonomic issues, the need for more frequent breaks and increased productivity were also reported.
Are the positive effects reported by participants in stretching programs a result of the break from work or the act of stretching? Henning et al attempted to answer that question in their 1997 study. In addition to a control group, 19 computer operators were prompted to take either three 30 second breaks or one 3 minute break in each hour of computer work performed. Half of the participants were prompted to perform five stretches during the break. It was up to each individual to decide which stretch to do, but protocols were given for six areas of the body: (1) fingers, hands and forearms, (2) fingers and wrists, (3) chest, shoulders and upper back, (4) shoulders and neck, (5) both sides of the trunk, (6) lower back. Workers were instructed to perform 5 stretches per hour and hold each stretch for 15 seconds. The participants mood and discomfort levels were monitored for a 2-3 week baseline period and 4-6 week treatment period. Of the 19, those in the group that included short rest and stretching reported lower levels of discomfort and higher productivity than those that had a rest break only and the control group. The author concluded “frequent rest breaks can improve the safety and health of workers performing computer-mediated work with little risk of productivity loss.”
Computer workers are not the only workers that could benefit from a stretching program. Moore implemented a stretching program for workers in a pharmaceutical manufacturing plant with the goal of preventing muscle strains. Over a 2 month period, 60 employees participated in 36 stretching sessions. A detailed description of the stretching protocol was not included. Flexibility was measured by performing several flexibility stretches, including the sit and reach, bilateral body rotation, and shoulder rotation tests. Each worker performed a 5-8 minute stretching routine 5 times a day. The routine included stretches for the neck, shoulder, arm, trunk, hip, back and legs, but a detailed stretch protocol was not included. Upon completion of the program, participants reported an increase in flexibility, physical conditioning, overall self-worth, and body attractiveness. Most importantly, there were no reported work-related injuries during the program period. The author concluded that the implementation of a stretching program can potentially decrease work-related MSD due to increases in flexibility. Limitations to this claim include the fact that there was no control group and the exercises were not given in detail, so the trial can not be replicated.
In 2005, Holmstrom and Ahlborg evaluated a stretching routine performed by 47 male construction workers. The stretching routine consisted of a 10-minute morning warm-up performed for 3 months on site. Muscle stretchability, joint flexibility, and muscle strength and endurance were monitored. The warm-up included arm-swings combined with knee-bendings, shoulder lifts, leg kicks, spinal movements, and transfer of body weight from side to side and jogging. Each session was concluded with stretching, including hamstring, quadricep, and calf stretches. At the conclusion of the two month period, thoracic and low-back mobility and plus hamstring and thigh stretchability were improved. There was an improvement in back endurance but no measurable gain in muscular strength. The authors concluded their morning warm-up was beneficial for increasing or maintaining joint and muscle flexibility as well as back muscle endurance in strenuous working conditions.
In 2003, Ludewig and Borstad studied a controlled group of 67 construction workers performing an 8-week home stretching program consisting of five shoulder stretching and strengthening exercises. All participants were administered the Shoulder Rating Questionnaire (SRQ) initially, then divided into an intervention and control group. The intervention group received instructions for (1) posterior shoulder stretch, (2) pectoralis stretch, (3) upper trapezius relaxation exercise, (4) serratus anterior strengthening exercise (5) external rotation strengthening exercise with arm at side and arm abducted. The stretches (1 and 2) were to be completed 5 times daily for 30 seconds each. The relaxation exercise (3) was also to be performed 5 times daily. The strengthening exercises (4 and 5) were to be performed 3 days a week. At the conclusion of the 8-week period, all participants were again administered the SRQ for comparison. It was found that the intervention group displayed a significant improvement from pre-test to post-test, as well as reported reduction in pain. The control group remained essentially the same. The authors concluded that a home exercise program can be effective in reducing symptoms and improving function in construction workers.
There are limitations to the studies presented. In several of the studies, there was no control group from which to draw comparisons. Also, is several studies, the exact stretches and their frequency were not included in the publication, so their findings can not be repeated. In addition, worker compliance and participation may not have been complete. Henning’s computer-based stretch-reminder program came with a delay/skip this stretch session option. They found that workers were much more likely to skip the stretch on busy days, when they may have needed the stretch the most. Other programs admitted that most participants did not follow the stretching protocols 100% as written.
While none of these studies conclusively proved that their stretching program prevented or reduced work related MSD injuries, all of studies reported a positive impact on the majority of the participants. Several of the studies reported a measurable decrease in pain or discomfort and an increase in flexibility or range of motion. And as Moore reported, an increased sense of self-worth is a beneficial trait for any employee. In addition, there is quite a body of evidence now that suggests physically active people live longer and have lower morbidity than those who are inactive. As a whole, our country is experiencing a reduction in the manufacturing industry resulting in a larger portion of workers performing sedentary jobs for a large proportion of the day, making them at a higher risk for chronic disease. It seems as though the workplace is a convenient venue to promote physical activity since most an employee’s waking hours are spent at work. The potential benefits for adopting a stretching/exercise program could be reduced absenteeism, increased productivity, increased stress tolerance, and improved-decision making, all of which could result in better bottom line and more content employees. (12,13)
1. Bureau of Labor and Statistics occupational safety and health definitions. Available from: http://www.bls.gov/iif/oshdef.htm
2. Praemer A, Furner S, Rice DP. Musculoskeletal conditions in the US. Available from: http://medicalreporter.health.org/tmr1099/orthopaedics.html
3. National Institute for Occupational Safety and Health. Ergonomic guidelines for manual material handling. DHHS Publication No. 2007-131. Washington, DC: US. Department of Health and Human Services, Centers for Disease Control and Prevention, NIOSH. Available from: http://www.cdc.gov/niosh/docs/2007-131/pdfs/2007-131.pdf
4. Choi S, Woletz T. Do Stretching Programs Prevent Work Related Musculoskeletal Disorders? Journal of Safety, Health, and Environmental Research. Available from: http://www.asse.org/academicsjournal/archive/vol6no3/feature02.php
5. da Costa B, Vieira, ER. Stretching to Reduce Work-Related Musculoskeletal Disorders: A Systematic Review. Journal of Rehabilitation Medicine, 2008; 40: 321-328.
6. Trujillo L, Zeng X. Data Entry Workers Perceptions and Satisfaction Response to the “Stop and Stretch” Software Program. Work, 2006; 27: 111-121.
7. Saltzman A. Computer User Perception of the Effectiveness of Exercise Mini-Breaks. Available from: http://www.tifaq.org/articles/excersize_mini-breaks-may98-arthur_saltzman.html
8. Henning RA, Jacques P, Kissel GV, Sullivan AB, Alteras-Webb SM. Frequent Short Rest Breaks from Computer Work: Effects on Productivity and Well-Being at Two Work Sites. Ergonomics, 1997; 40: 78-91.
9. Moore, TM. A Workplace Stretching Program. Physiological and Perception Measurements Before and After Participation. American Association of Occupational Health Nurses Journal, 1998; 46: 563-568.
10. Holmstrom E, Ahlborg. Morning Warm-up Exercises – Effects on Musculoskeletal Fitness in Construction Workers. Applied Ergonomics, 2005; 36: 513-519.
11. Ludewig PM, Borestad, JD. Effects of a Home Exercise Programme on Shoulder Pain and Functional Status in Construction Workers. Occupational Environmental Medicine, 2003; 60: 841-849.
12. McEachan RR, Lawton RJ, Jackson C, Connor M, Meads DM, West RM. Testing a Workplace Physical Activity Intervention: A Cluster Randomized Controlled Trial. International Journal of Behavioral Nutrition and Physical Activity, 2011; 8:29.
13. Kreis J, Bodeker W. Health-Related and Economic Benefits of Workplace Health Promotionand Prevention: Summary of the Scientific Evidence. Available from: www.enwhp.org/fileadmin/downloads/IGA-Report_3_English.pdf