It does not come as a surprise to find health as a priority of most people today. It is based on the reasoning that stressors abound regardless of the chosen work area. Some even get sick and require to be admitted to the hospitals by their attending physicians because they need rest from such a heavy workload in their offices.

In order to promote a healthy lifestyle, an increasing number of entrepreneurs put up restaurants serving healthy food like organic and vegetarian dishes, fitness clubs with tailor made programs for their customers and supplementary items like tablets and capsules in the drugstore.

The next few paragraphs will spill the details on the perks that a healthy person can gain if he is consistently subscribing to a balanced diet, maintaining a regular exercise program, and visiting the general physician regularly. Read on so that you can apply them to your life.

First Advantage of being Healthy

The first advantage when you are healthy is that you will have a better work performance. This would be possible because you are at the top of your game. You can accomplish more things at a faster rate compared to your colleagues who are living the sedentary lifestyle. You will have more energy to last you throughout the day. You will also be alert during business transactions and board meetings that your superiors will definitely see you like an Energizer bunny.

This go-getter attitude will definitely make you stand out from the rest and heighten your chance of getting a raise, and maybe even a promotion. This is surely one temptation that you should keep in mind if you are deciding to strive for a healthier status.

Second Advantage of being Healthy

Second, if you are healthy, you will decrease your risk of getting various lifestyle diseases like diabetes mellitus and hypertensive cardiovascular disease. Everybody is well aware of the fact that most illnesses can be attributed to poor or wrong nutritional intake of food such as those with excessive fat, cholesterol and sugar. You have to consider also that the typical office employee has minimal exercise because they are stuck in their cubicles the entire day finishing their required assignments.

Third Advantage of being Healthy

Third, being healthy means that your body has the capacity to live longer. Longevity will help you do more things life especially if you have already retired from your day job. You will have no need to hire a private duty nurse. Instead, you can go on your own to wherever you want to. You can also opt to take your grandkids along with you to the zoo or to the museum for a bonding moment. You can do this even if you reach the ripe old age of 100.

Finally, you can deal with people in a more harmonious manner. Since you are functioning at an optimum level, you will be alert in making crucial decisions. You will also feel more comfortable as you carry out your daily meetings and discussions with your boss or your subordinates. Without a doubt, they will find you a pleasure to work with and they will not hesitate in approaching you. Unlike the unhealthy ones who feel like they are carrying the burden of the world on their shoulders, you will not feel grouchy because you have no reason to do so.

Marijuana affects users mentally in many ways while the user is high, but there is no evidence that it makes any changes to the users mental state when the high wears off. It does not appear possible for people to overdose on marijuana. Most of the physiological harms of marijuana are from the smoke inhaled into the lungs and not THC.

While marijuana is not known to weaken or strengthen the immune system as a whole, people with immune system deficiencies should avoid marijuana smoke because it weakens alveolar macrophages ability to defend against fungi, bacteria, and tumor cells in the lungs. Marijuana smoke does increase the risk of respiratory illness and heavy smokers will have changes in the lining of the respiratory tract.

Medical Marijuana Effects on Users | Fact or Faction

There is no conclusive evidence that marijuana can cause cancer to date, but there is a strong likelihood that further research will find correlations. First time users of marijuana will experience a rapid heart beat for the first few minutes of inhaling, and some users will also have an increase in blood pressure for a few minutes.

First time users will also have a decrease in testosterone or estrogen. Both of these “first time user” effects cease to exist in more experienced users. Pregnant women should avoid inhaling marijuana smoke because it causes a higher mutation rate, but has little effect on the long-term cognitive abilities of the child.

Smoking marijuana (or inhaling any smoke) can cause health problems. But I feel that people that smoke marijuana in moderation are putting themselves at less risk than those that smoke tobacco cigarettes in relative moderation and putting themselves at less risk than those that drink heavily (whether occasional binge drinking or drinking more than a moderate amount on a daily basis). I do not feel that marijuana poses enough threat to make it an unconscionable health problem for our society.

But I do feel that those that smoke marijuana heavily are taking more risks than can be justified. Ultimately I think that people should know the risks involved and make their own decision as to whether or not they are willing to take on those risks.

I think the best way I can end this article is to leave you with someone else’s take on how safe marijuana is on a relative scale. A few years back the United States’ Drug Enforcement Agency had a trial lasting a couple years to determine if medical marijuana was safe enough to be considered for medical use. The case was heard in the court DEA’s own administrative court. After the DEA’s judge read thousands of pages of testimony and heard from dozens of witnesses he declared that marijuana is “one of the safest therapeutically active substances known to man.”

Marijuana is not associated with any increase of mortality. Most physiological harms that are attributed to marijuana are actually from the act of smoking, or inhaling smoke. They are very similar to tobacco smoke.

THC and the Immune System

THC both increases and decreases different types of immune system cells, but after much research there is no proof that it either weakens or strengthens the immune system.

Marijuana Smoke

Marijuana smoke is very similar to tobacco smoke, and tobacco smoke has been found to cause lung diseases like cancer and emphysema. Marijuana users typically do not smoke anywhere near the volume of marijuana as tobacco smokers smoke tobacco. One joint usually has about half the smokable substance as one tobacco cigarette.

But because marijuana is not usually filtered and users tend to hold the medical marijuana in their lungs for longer periods of time, up to four times as much tar can be deposited in the lungs per ounce of smoked marijuana as an ounce of tobacco. There is an additive effect of smoking both tobacco and marijuana.

Chronic Bronchitis

Smoking marijuana increases the users risk of respiratory illness. Interestingly people that have been smoking marijuana 10 years or more are usually not at a greater risk of having respiratory problems, but those that have been smoking for less than 10 years are. This is most likely because the people that do have respiratory problems discontinue smoking marijuana, and those that don’t quit usually haven’t had many problems. From a random sample 15-20% of people who smoke marijuana but not tobacco will report chronic bronchitis, and 20-25% of those that smoke tobacco but not marijuana will report chronic bronchitis. Those that smoke both will be at a higher risk.

Bronchial Tissue Changes

Heavy marijuana smokers will have changes in the lining of the respiratory tract. There will be more redness and swelling of the airway tissues and increased mucus secretion. Smokers of marijuana and tobacco have significantly more cellular and molecular abnormalities in the bronchial epithelium cells. There is an association with those abnormalities and increased risk of cancer. A marijuana only smoker that smokes about 21 marijuana cigarettes a week has about the same amount of abnormalities as a tobacco only smoker that smokes about 25 tobacco cigarettes a day. Once again those that smoke both will have an additive effect.


To date, there is no conclusive evidence that marijuana causes cancer in humans. However, marijuana has many of the same carcinogens as tobacco. The problem with finding a correlation with marijuana and cancer is that respiratory cancer requires a long-term exposure to smoke. Marijuana usage has only become popular since the late 1960’s, and most people only smoke marijuana when they are younger. As some habitual marijuana smokers get older and have been smoking marijuana for several decades there could very well be proof that marijuana causes cancer, but as of today there is no conclusive evidence that this is the case.

Using Cannabis During Pregnancy

THC can interfere with the implantation of the embryo making it harder for a woman that smokes marijuana to get pregnant. Like tobacco smoke, pregnant women should not expose themselves and their babies to marijuana smoke. Babies born to mothers that smoked marijuana during pregnancy weighed an average of 3.4 ounces less than other babies. Newborns of mothers that smoke either tobacco or marijuana have a higher mutation rate than those of non-smokers.

Jamaican women often drink marijuana tea as opposed to smoking marijuana and their children do not show any neurobehavioral problems. Whereas the cognitive abilities of babies born to mothers that smoked marijuana during pregnancy often show detectable deficits up until the age of 5, when the deficits are no longer detectable (this is for global measures of intelligence such as language development, reading scores, and visual or perceptual tasks).

There has been evidence that children exposed to marijuana parentally may exhibit deficits in executive function as late as 9-12 years old. That means they have trouble planning, anticipating, and suppressing behaviors that are incompatible with a current goal, and are often described as hyperactive or impulsive. However, in the case of the executive function the cause of the deficit could be related to the reason the mother was smoking marijuana during pregnancy, and not necessarily the marijuana exposure.

Marijuana use can disturb the T and B cell function of the bodies lymphocytes, but it is a very small disturbance that is usually within normal limits. Just like tobacco smokers, alveolar macrophages, the lungs immune-effector cells, have difficulty destroying fungi, bacteria, and tumor cells in the lungs. For this reason people with immune system deficiencies should avoid marijuana usage.

Cardiovascular System

Marijuana smoke and THC can cause a rapid heartbeat of up to 20-100% above the baseline during the first 10-20 minutes of smoking, and some users have an increase in blood pressure. Experienced users of marijuana have a tolerance for this effect, so it is not usually seen in marijuana users that have been using marijuana regularly. The tolerance can be built in as little as a week of frequent usage. The cardiovascular changes usually are insignificant to younger users. Older people should be aware of this fact though, as their bodies typically cannot handle cardiovascular changes as well.

Reproductive System

Marijuana and THC inhibit the release of luteinizing hormone, which is responsible for signaling the release of testosterone and estrogen. Again a tolerance is seen in this effect as well, meaning regular users of marijuana typically do not have any reduction in testosterone and estrogen, only those that have just begun smoking marijuana.

So you ask, how do I get a MMJ Recommendation?

Your recommendation will then be signed by the physician stating that you have been evaluated and approved in our clinic for a medical condition.

With this recommendation you will be permitted to grow, purchase and transport medical marijuana in quantities pursuant to California legal guidelines. (An outline of these and other guidelines will be given to you before you leave)

We will also include your approval in our secure encrypted patient verification data base (SafeAccessMD) which can be accessed 24/7/365 via phone or internet by authorities wishing to verify your legal status.

The process is simple

  • Step-1 — Walk in or call for an appointment to arrange a convenient time for you to see one of our knowledgeable physicians.
  • Step-2 — You will fill out a few simple forms describing your medical complaint, and answer a few questions. One of our expert physicians will conduct a medical evaluation to assess your medical condition.
  • Step-3 — Once the Doctor has spoken with you and evaluated your complaint (and you are approved) the Doctor will hand write a detailed evaluation for inclusion in your medical records.

What Do I Bring?

A valid driver’s license, CA photo ID, passport, or other valid form of identification, show proof you live in California. This can be rental/lease Agreement, utility bill, phone bill, Car registration etc. This document Must have your name and address.

Have access to a list of medications you are taking, including dosages and directions. Any reports or diagnosis from your primary care physician if you have one.

Over the past twenty years, people in the state of California have grown more and more comfortable with the idea of marijuana being used as medicine. Today, clinics and dispensaries across the state provide patients with an easily accessible and legal way to obtain their medicine. Here at Green Cross Evaluations, we want to make it even easier for you by offering some of the most affordable medical marijuana evaluations in San Diego, CA. We will serve you with an understanding outlook on your health needs.

Bringing yourself to consider trying medical marijuana out may not be an easy thing to do, especially if you are used to conventional prescription medication. If you identify with those who are unsure about the benefits of medical marijuana, call us or come talk to us and we will answer any questions that you may have. Our staff is extremely knowledgeable about the health benefits and various uses of cannabis. We can also educate you on the many variations in strength and delivery systems if you so choose.

Making sure that people are educated about the facts of medical marijuana has always been a top priority to us. Some dispensaries and clinics give biased information in order to make more sales, but here at Green Cross Evaluations we are dedicated to your health. We will give you all the knowledge you need in order to incorporate medical marijuana use into a healthy lifestyle. All you need to bring is your state I.D. and your medical records. If you bring someone in you get a free wallet card, so visit us today!


I am proud to announce that the publication of this issue of the HERL newsletter marks the third complete year of its’ circulation. When the first edition was released in Spring of 2002, we had about 500 readers. Now, over 1,400 people receive the HERL newsletter, and our distribution list is growing every day. We thank our many dedicated research participants and other newsletter readers for their interest, support, and contributions to this publication.

Our faculty and students have merited several notable awards and achievements since our last update. HERL director Rory Cooper was appointed by the University of Pittsburgh to be the first holder of the Federation of Independent School Alumnae Foundation Paralyzed Veterans of America (PVA) – Chair for Rehabilitation Engineering. Dr. Cooper’s appointment to this endowed Chair, one of the highest honors any university can bestow, is the result of a dynamic career in the field of rehabilitation engineering and assistive technology.

In October Dr. Cooper was invited by VA Central Office to participate in a White House/VA conference entitled, “Emerging Technologies in Support of the New Freedom Initiative: Promoting Opportunities for People with Disabilities.” The conference highlighted Federal support for disabilities, development in science and technology, and innovation leading to new products, businesses, and jobs. The conference also provided a forum for discussing ideas about support for future research and technology development.

This fall, Dr. Cooper accepted an invitation from the Hong Kong Polytechnic University to serve for a second two-year term as an Honorary Professor in their Jockey Club Rehabilitation Centre. He was also invited to be an adjunct professor of Xi’an Jiaotong University, China, for 4 years.

In the last newsletter we announced that HERL doctoral student Ian Rice would be competing in the Paralympic Games in Athens, Greece, September 17th -September 28, 2004. He competed in the 100m, 200m, 400m and 800m wheelchair races, finishing fourth in the 100 meter race and sixth in the 200 meter race. He was the first American to finish. On Oct. 9th , Ian placed first in the Chicago marathon, beating the 2nd place finisher by 45 minutes. He also placed first in the Detroit marathon on October 24th.

Book Chapters

In Press

Textbook of Rehabilitation Engineering, Toshiyasu Yamamoto, Ph.D., Editor, Ishiyaku Publishers Inc., Tokyo, Japan, in press

Biomechanics of and Interfaces for Wheelchair Mobility, R.A. Cooper, M.L. Boninger, A.M.Koontz, D.M. Spaeth, M.J. Dvorznak, R. Cooper, A. Dobson

Physical Medicine &Rehabilitation Secrets, 3rd Edition, Bryan O’Young MD, Mark Young MD, Steven Steins MD, Editors, Elsevier Press, in press

Wheelchairs: Manual and Power, R.L. Kirby, R.A. Cooper, M.L. Boninger

Assistive Technologies: Catalysts for Adaptive Function, M.L. Boninger, H. Choi, K. Johnson, M.A. Young, S.A. Steins, A. Sears

The Engineering Handbook on Smart Technology for Aging, Disability and Independence, A. Helal, M., Mokhtari and B. Abdulrazak, Editors, John Wiley & Sons. Computer Engineering Series, in press, 2007.

Technology for Successful Aging and Disabilities, A. Karmarkar, E. Chaves, R.A. Cooper

Musculoskeletal Tissue Regeneration: Biological Material and Methods, W.S. Pietrzak, Editor, Humana Press, in press, 2008.

Muscle Repair After Injury and Disease, F. Ambrosio, Y. Li, A. Usas, M.L. Boninger, J. Huard

Spinal Cord Medicine: Principles and Practice, 2nd Edition, Vernon Lin, M.D., Editor, Demos Medical Publishing, New York, NY.

Wheelchairs and Seating for People with Spinal Cord Injuries, R.A. Cooper, R.M.  Cooper, M.L. Boninger, E. Teodorski, T. Thorman, T. Peleshi

Musculoskeletal Pain and Overuse Injuries, M.L. Boninger, J.L. Collinger, R.A. Cooper, A.M. Koontz

Stroke Recovery and Rehabilitation, Carolee J. Winstein, Ph.D., Joel Stein, Richard Harvey, Richard Zorowitz, Richard Macko, Editors, Demos Medical Publishing

Seating, Assisitive Technology, and Equipment (Chapter 35), R.A. Cooper, B. Brewer, R.M. Cooper, K. Hill, P. Karg, A. Karmarkar, A. Lane, R. Little, T. Peleshi


Spinal Cord Injuries: Management and Rehabilitation, S.A. Sisto, E. Druin, M. Sliwinski, Editors, Mosby Elsevier, St. Louis, MO, 2009.

Sports and Recreation for People With Spinal Cord Injuries (Chapter 19), I. Rice, R.A. Cooper, R.M. Cooper, A.R. Kelleher, A. Boyles, pp. 455-477

Wheelchair Skills (Chapter 15), A. Koontz, M. Shea, pp. 351-379

Transfer Techniques (Chapter 8), A. Koontz, E. Druin, pp. 185-208

Wheelchair Standards

The Human Engineering Research Laboratories houses one of the most complete wheelchair testing facilities in the country. The facility is able to conduct a majority of the ISO or ANSI/Resna testing which is required for FDA approval. Both manual and powered wheelchairs can be tested. All manner of destructive and non-destructive testing is available. Testing is conducted on equipment that has been designed and built on site and has become the standard for testing the world round.

Tests range from comparative measurements of turning radii, wheelchair size and seating dimensions to strength testing of armrests, footrests and seat backs to endurance testing of motors, axles and transmissions. Each endurance test subjects the device to three to five years of normal use in a fraction of the time. Not only can the standard tests be run, specialized testing is also available. All test equipment is calibrated on a regular basis to insure accurate data. Innovative approaches to gathering data through electronic and electro-mechanical devices guarantees results that are complete and reliable.

Not only has HERL contributed to the design and construction of wheelchair testing equipment, they are represented on numerous standards committees that draft new and better wheelchair standards. As the world of wheeled mobility expands to meet current and future needs of the population, so must the standards be expanded and revised to provide safe and reliable products to the users who depend on them.

Newer materials and designs that offer safer, lighter and more dependable devices require that standards be constantly updated. The current wheelchair test standards are covered in a two-volume set. Each item is constantly monitored for its acceptability as a viable standard and suggestions for revision are noted and offered at the standards meetings.

Principal Investigator/s: Chris Willems, ME, Donald Spaeth, PhD
Co-Investigator/s: Rory Cooper, PhD, William Ammer, BS


The game wheels training system is an exercise station developed for individuals who use manual wheelchairs. The manual wheelchair is positioned on top of two dynamometer rollers and secured so that it remains stationary while the occupant propels the chair’s rear wheels through the hand rims. The rear wheels in turn drive the rollers.

A key innovation is the use of a video game to provide motivation to the consumer during exercise. The game used is one that would typically be operated with a joystick. On the game wheels system, the velocity of the wheelchair wheels controls the game. A special circuit reads the velocity of the rollers and uses a computer chip to convert these values into joystick signals. The occupant performs left and right joystick actions by pushing the wheels at different speeds. A large computer monitor is mounted at eye level in front of the wheelchair so the user can enjoy the game.

The present project has completed two, third generation prototypes of the game wheels system and completed a focus group study it to determine whether it meets new design criteria. Improvements include weight reduction, making the mounting and dismounting from the rollers entirely user managed and reducing the overall length of the machine through smaller rollers and a shorter loading ramp.

The “Trainer” is a new version of the GameWheels concept. The Trainer uses ergometers borrowed from the bicycle industry these bear directly on the wheelchair’s rear wheels. There is no dynamometer system at all. A specially designed pair of lever arms allows the occupant to raise the wheelchair’s rear wheels off the floor to allow “rolling in place”. The trainer will also operates video games and is light and small enough for home use.

We invite you to join our Research Experience for Undergraduate (REU) Internship Program at HERL in Assistive Technology.

10 week paid mentored- research experience
Possible housing and travel allowance
Work closely with faculty and graduate students with diverse background (medical, engineering, exercise physiology, robotics, computer science, and physiology, robotics, computer science, and physiology)
Field trips, lecture series, workshops
Learn about graduate school and exciting careers in assistive technology

Examples of 2007 Projects:

Joystick use for Virtual Electric Power Wheelchair Driving in Individuals with Tremor
Development and Testing of Drop-off Detection System for Power Wheelchairs
Carbon Fiber Handcycle
Inside out Vision
Safe Driving
Integration of an Electric Powered Wheelchair and a Robotic Arm for Coordinated Manipulation
Mouse Development for Computer Access
AT Suitability for Those with Multiple Sclerosis
Robotics Therapy
The Effects of Wheelchair Axle Position on Shoulder Forces
Seating Coach