Published by Ergovera Ergonomic Consulting to help you keep up on ergonomic innovations, so you can protect your employees and increase their productivity. Please pass it on to your colleagues and friends.
Increased numbers of back disorders are expected in the next decade as the workforce ages and as young people with "under conditioned" bodies seek employment. As less women take hormone replacement therapy (HRT) due to the harmful side effects of certain (primarily estrogen) hormones, we may see a greater prevalence of osteoporosis and pre-osteoporosis (osteopenia) conditions. This may or may not prove to be a problem for employers, but it is at least worth paying attention to as time goes on.
On a side note, I once did an evaluation on an 82 year old man who did very physical work at a library. He had the best posture, a sturdy and stolid physique, and perfect body mechanics (if there is such a thing!). He had no physical complaints of discomfort anywhere in his body!
Thinking about what the future may bring made me ask: "What can employers do and why should they worry at all about an ageing population"? What employers can do is discussed at the end of this section of the newsletter; the "why" they should worry is primarily sky-rocketing workers compensation costs and productivity issues. Healthy workers are more productive and are less likely to get injured, though I must say that I have met some exceptions to this rule in my career. These are usually Type A people who "don't have time to take breaks" and don't seem to be fully aware of their bodies and what they are doing to them.
Going back to my initial interest in osteoporosis and my own spine, I recently received the results of the bone mineral density X-Ray testing I had on my lumbar spine and hip. Evidently, I don't have osteoporosis but I do have some decreased bone mineral density (BMD) of my lumber spine (my hip is okay). I'll know more after my doctor appointment. Thus, I eagerly dove into to two rather complicated studies on osteoporosis prevention and exercise.
I looked at just two studies (rather than my usual three) due to the length and the complicated nature of the research. The first study I looked at was "The Erlangen Fitness Osteoporosis Prevention Study." Like previous research on nutrition and osteoporosis, this study looked at postmenopausal women and gave the participants calcium and vitamin D. Participant selection precluded any hormone replacement therapy. After participants completed a 14 month long vigorous exercise program, the researchers found that:
- Significant improvements in bone mineral density of the lumber spine in the exercise group.
- Significant decreases occurred in bone mineral density in the control group (whom did not participate in any exercise program).
- Total hip bone mineral density remained stable in the exercise group, while the control group experienced a slight decrease in bone mineral density.
- Significant increase (11% to 32%) in isometric strength in all muscle groups of the exercise group.
- An increase in maximal oxygen consumption (VO2 Max) in the exercise group (a sign of increased overall cardiovascular health).
The second study I looked at had 1/2 of their participants on hormone replacement therapy and half who were not. This study used the "Bone Estrogen Strength Training" (BEST) and looked at the effects of weight bearing and resistance training exercises on bone mineral density in 142 postmenopausal women. The participants received calcium supplements throughout the study. The researchers found after participants completed one year of a weight lifting strength training program that:
- Weighted squat exercises appeared to be the most beneficial to increasing bone mineral density, though in the end they hesitated to make definitive recommendations for site-specific (muscle group areas) training programs and recommended a well-balanced strength program.
- The more weight women lifted in a one year period the more their hip bone mineral density increased.
- Weighted march exercises showed a marginally significant effect on hip bone mineral density.
- Hormone replacement therapy, though not the focus of the study, did have an independent effect on bone mineral density on bones in the hip and lumbar spine. They concluded that bone modeling (development of bones) may be more affected by hormones than by exercises in certain hip and lower back bones.
So get your employees exercising! No excuses. Even if you don't have a gym or space for exercise mats you can get creative. Here are some ideas:
- Start a walking incentive program, and be sure to have a "reward" that they find desirable. You may want to survey your employees on possible reward items such as gift certificates.
- Consider procuring weights to increase the effects of weight bearing exercises. Weighted vests or simple 3 lb. wraparound weights that employees can put on their wrists or ankles are all appropriate choices.
- If you do have a gym, consider utilizing a login\out system that tracks time and frequency. Develop an incentive program to encourage regular workouts.
- If you have an appropriate room (hard surface or thin carpet) for a dance or body movement class consider hiring an instructor to teach an ongoing class.
Be sure to target those who are "too busy" to take a break (those type A's that are prevalent here in the valley). When appropriate, recruit "leads" who can monitor their units and announce "exercise time" throughout the day or send group e-mails periodically during the day with break and exercise reminders. Try to get people motivated by saying such things as "do you value your health, if so, you should take a break and get a short walk." You may want to survey your employees to determine the amount of time spent on computer and regarding their individual break habits. For those who score high on time spent at the computer and low on break time, consider a break reminder software program such as www.RSIGaurd.com.
Coming Change in Publication Frequency of this Newsletter
When I began publication of this newsletter I did not realize certain factors that have become of increasing concern.
- In the first place I did not know that it would take at least three full days to research, write, and edit this publication.
- In addition, I did not realize that many issues I wish to raise have an immense body of written articles and studies. Working through these articles could become a full time task.
- And finally, I have found that a monthly newsletter takes too much time away from my increasingly busy work schedule. My primary purpose in starting Ergovera was my concern for the health and welfare of workers. I cannot afford to neglect my practice to devote so much time to the newsletter.
Because of these factors I am changing the frequency of publication to four times per year. I will begin quarterly publication in December. The newsletter will then appear in March, June, September, and December. My goal is to send out the newsletter on the 15th of the month.
I take this step reluctantly because I believe in the importance of the issues I raise. However, I am sure my readers will understand the reasons for my decision.
Have a healthy day,
Deidre Rogers, RN, MS, CAE
A medium-sized Germen study (Kemmler, et al.) evaluated the effects of a vigorous, combined high-impact, strength, and endurance training program on bone mineral density and osteoporosis prevention. The study consisted of 100 postmenopausal women (41 of whom did not exercise) who participated in a 14 month exercise program. Dual-energy x-ray absorptiometry was used to measure bone mineral density. The study used a non-randomized design which is less desirable than a randomized design (where participants are randomly assigned to different groups). This was due to the fact that many of the women, who were highly motivated and wanted to exercise, did not want to be in the control group.
The experiment program consisted of two weekly (60 to 70 minutes) group training sessions, with approximately 15 participants per session; and two additional 30 minute individual home sessions. During the group training classes, participants performed endurance training (e.g., running), strength training (using both machines and free weights), jumping (beginning five months after the study began), and stretching. The intensity of the strength training was increased gradually as time went on to minimize injury risks. The home sessions included isometric and elastic belt exercise and rope skipping.
The researchers found that a low training frequency (less than two sessions per week), even if combined with a high level of intensity was not as effective as a moderate or high level of training frequency. In 80% of the exercise participants the percentage of bone mineral density was increased more than the average change in the control group participants. The researchers had a low drop out rate of 15% and had to two participants, who exercised so much more than the protocol that they had to be excluded from analysis.
A medium-sized United States study (Cussler, et al.) examined the relationship between weights lifted in one year of progressive strength training and change in bone mineral density in 140 postmenopausal women. Half of the participants were taking hormone replacement therapy. They were randomly assigned to exercise or no-exercise groups.
The exercise group trained three days per week (on non-consecutive days) at a community facility with a large gym under supervision of an on-site trainer. The exercise sessions lasted for 60-70 minutes and consisted of stretching, balance exercises, weight-bearing activities for warm-up, weight lifting, and additional weight bearing activities (e.g., jogging, skipping, and marching), stair-climbing, and step box exercise performed while participants wore weighted vests.
The researchers found that the weighted march exercise showed a marginally significant effect on hip bone mineral density. They found that the group on hormone replacement therapy had better bone mineral density of the hip than those who did not take hormones. They discovered large variations in individual levels of performance and because of this concluded that the weight lifted in one exercise is not "independent" of other exercises performed by the participant during a session. The study's drop-out rate was 20%. The researchers recommended a comprehensive strength training program as well as hormone therapy for women who have lower levels of bone density in specific areas of the hip and in the lumbar spine.
Wolfgang, K., Klaus, E., Jurgen, W., Johannes, H., Willi, A., & Toda, T. (2003). The Erlangen Fitness Osteoporosis Prevention Study: A Controlled Exercise Trial in Early Postmenopausal Women With Low Density - First-Year Results. Archives of Physical Medicine and Rehabilitation, 84, (5), 673-682.
Cussler, E., Lohman, T., Going, S., Houtkooper, L., Metcalfe, L., Flint-Wagner, H., Harris, R., Teixeira, (2003) Weight Lifted in Strength Training Predicts Bone Change in Postmenopausal Women. Medicine and Sciance in Sports and Exercise, 35, (1), 10-17.
Fun movement class designed to build strength, endurance, and increase flexibility
- Get warmed up with dance movements while listening to fun music,
- Perform Yoga designed for injured bodies,
- Do strength and endurance training,
- Stretch and relax.
Call Deidre at 831.335.8448 or send her a message now for more info.
Copyright © 2002, Deidre Rogers and Ergovera Ergonomic Consulting. All rights reserved. Reuse in any form must be requested and granted in writing.