Edition No. 16

Zavitz on Ergo:

The Facts About Stretching and Ergonomics

by Ben Zavitz, CPE

About Zavitz on Ergo

Zavitz on Ergo is a quarterly column in Priority Press, addressing ergonomics issues and trends. If you have questions you'd like to see answered in future editions, send them to Ben Zavitz at zavitzb@eorm.com.

Also in this Issue...

Six Steps to Developing a Successful EHS Training Program

Creating a Sustainable Future

Workplace stretching programs designed to reduce musculoskeletal injuries have grown in popularity over the last several years. Typically, these programs are an integral part of a company’s overall ergonomic program; however, sometimes they are the primary focus of the program. While working on a recent lean ergonomic project, EORM consultants noticed that our client incorporated a site stretching program into their work standards charts (charts that show what people do and how much time it takes to perform those activities). What interested us was the total amount of time used as well as the cost of this stretching program. Their program, which consists of stretching four minutes two times each day, costs on average $500 per person or approximately $100,000 per year for only eight product lines. The total impact of the stretching program on production equates in a loss of production profit of $5.1M.

Keep reading and you’ll learn that despite their popularity, workplace stretching programs may not be a practical or cost-effective ergonomic practice. In fact, current research points us in the opposite direction.

The 12 Things We Know About Stretching

Here’s what a review of scientific literature tells us about stretching:

Stretching before participation in athletic activities is standard practice for all levels of sports, competitive or recreational. Athletes, coaches, trainers, physiotherapists, and physicians recommend stretching in an effort to both prevent injury and enhance performance.
Stretching has been demonstrated to improve the flexibility of several joints (i.e., hips, knees, shoulders, trunk, and ankles).
Stretches need to be held for a minimum of 15 to 30 seconds to be beneficial.
Inadequate conditioning and warm-up prior to stretching increases the risk of injury and impairs performance. Some experts argue that warm-up is more important than stretching in the prevention of injuries in sports.
Stretching increases flexibility but has not been shown to prevent muscle soreness.
Lack of flexibility does not account for many muscle injuries that occur within a normal range of motion.
Stretching pre- or post-exercise does not reduce the risk of injury in competitive or recreational athletes.
The extremes of inflexibility and hyper-flexibility increase the risk of injury.
Injury is related to too much or too little flexibility. Little evidence exists that suggests a relationship between increased flexibility and a reduced incidence of injury. In fact, in some instances increasing flexibility may increase the rate of injury.
The President’s Council for Physical Fitness and Sports reported that stretching might not prevent injuries and may compromise performance.
Strength training, conditioning, and warm-up have an important role in injury prevention, and when stretching is done, it should be conducted in the context of adequate conditioning and appropriate warm-up.
The Centers for Disease Control and Prevention (CDC) recently concluded that the best available evidence indicates that stretching before or after exercise does not prevent muscle soreness or injury and that there is insufficient evidence to assess its effect on performance.

Stretching At Work

Based on the evidence above, why do so many companies endorse stretching programs in the workplace to prevent injuries? It is this author’s belief that there are three main reasons:

Stretching is perceived as a low-cost, low-risk solution that addresses workplace injuries. As stated earlier, stretching programs can have a huge impact on bottom-line costs.
Proponents of stretching programs address ergonomic issues using the medical model approach (i.e., fitting the employee to the job) and believe changing or adapting the employee to the job, which seems unfixable in their eyes, is the best solution.
No root cause investigation into the reasons people are getting hurt.

When you review the literature on the effectiveness of stretching programs in the workplace, one study published a few years ago on office exercise programs comes to mind. As part of this study, researchers evaluated 12 exercise programs representing 127 separate exercises. Findings of the study determined that several of the exercises were either not appropriate, too difficult to perform, or unsafe to perform. The following chart provides the specific details.

Area of the Body	Not Appropriate	Difficult	Unsafe
Neck	8%	4%	72%
Shoulder	45%	5%	93%
Elbow/Lower Arm	11%	13%	100%
Lower Back/Hip	64%	16%	100%
Knee/Lower Leg	53%	12%	82%

Two of the most interesting findings were: 1) 40% of the exercises replicated the same physical stressors of work that the ergonomics program was trying to eliminate, and 2) 90% of the exercises were not appropriate for individuals with acute or chronic musculoskeletal disorders.

Stretching Is Not Ergonomics

As defined, ergonomics is the science of fitting jobs to people, with the goal of eliminating or minimizing exposure to the ergonomic risk factors of awkward postures, forceful exertions, repetitive motions, contact stress/impact, and whole body or hand-arm vibration. The most effective way to address ergonomic issues is to redesign jobs through the use of engineering, work practice, administrative, or personal protective equipment controls (also known as the hierarchy of controls).

The three primary reasons why workplace stretching programs are not effective in reducing ergonomic risks or musculoskeletal injuries are:

They do not address the root cause of the problem. Simply put, stretching does not eliminate or reduce ergonomic risk factors and stretching does not fit within the hierarchy of controls.
The stretching program is fundamentally flawed. Most workplace stretching programs do not include adequate warm-up. The stretches are not held for a minimum of 15-30 seconds or the stretches replicate the same motions and muscles performed during work (i.e., bending forward to touch your toes, when the job requires prolonged forward back flexion).
The stretching exercises are not usable. Most stretches are based on athletic stretches that are either not appropriate for the workplace, are difficult to perform, or increase the risk of further injury in some individuals. One EORM ergonomist even experienced employees being injured performing exercises that were suppose to protect them.

And Finally…

Since most injuries occur during eccentric contractions within the normal range of joint motion, it is not clear how increasing the range of motion through stretching decreases injury risk. Make no mistake, stretching is a worthwhile activity but it needs to be conducted in a manner that is based on sound science and kept in the context of what it is--one element in an overall employee health and wellness program. If your ergonomic program is primarily based on an employee stretching program, your long term success in reducing injuries will be limited.

If you would like to see the list of references for this topic or would like to see a particular topic or subject in this column, please contact me.

Ergonomically Yours,

Ben Zavitz, CPE
EORM, Inc.
zavitzb@eorm.com.
tel: 781.938.9152 ext 106