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By Michael A. Smyser


Discovery that controlled isometric exercises can be used to lower resting blood pressure

began like many other important technical chance. A researcher

discovered the effect during work with military aviators during the late 1960’s when the F-16

aircraft was being introduced to the U.S.Air Force. Because of the strength of new technology

materials used in the F-16 and its "fly-by-wire" control response, it was realized that the aircraft

could easily out-perform the human body. Many pilots were experiencing "blackout" during

pullouts from a dive or tight radius turns at high speed. Blackout is caused by high gravitational

loads imposed on the longitudinal axis of the body (head to foot), leading to impairment or

loss of vision when blood supplies leave the eye’s retina. These "G stress" maneuvers had

been historically offset by the use of pilot "G suits" designed to keep blood trapped in the

upper extremities of the body.

Isometrics to Temporarily Raise Blood Pressure
In 1969, Dr. Ronald Wiley, a cardiopulmonary physiologist at Miami University in Oxford, Ohio, was one of two researchers commissioned by the U.S. Air Force to formally study pilot use of isometric exercises to enhance their G-force tolerance. It had been known for some time that when a person performs an isometric muscular contraction, blood pressure rises. The proposed research for the U.S. Air Force was designed to study the use of isometric exercises to raise blood pressure in pilots during high G-load maneuvers to increase pilot tolerance to "tunnel vision" and eventual "blackout". This was the first formal study of its type to be conducted on this subject.

U.S. Air Force Studies

The research was conducted at Wright Patterson Air Force Base in Dayton, Ohio in cooperation with the U.S. Air Force Surgeon General’s office located at Brooks AFB in San Antonio, Texas. The human centrifuge, located at WPAFB, was equipped with a hand-grip dynamometer used to elevate blood pressure in tests subjects prior to and during G-force loads. Each test subject riding the centrifuge was wired to measure intravenous blood pressure at eye level. The test subject was also asked to monitor degree of "tunnel vision" by looking at a light bar mounted in their path of vision. Test subjects were asked to grip the dynamometer to a point of fatigue so that maximum elevation of blood pressure could be achieved prior to imposing the G-stress. These isometric exercise experiments were conducted systematically for 10-12 successive days. All test subjects were measured for their resting blood pressures prior to performing these daily isometric exercises. Two subjects in one test group were observed to have resting blood pressures in the "high normal" or "borderline hypertensive" range prior to conducting the study.

Serendipity in Science
Following the tests, while summarizing the experimental results, Dr. Wiley observed from the test data that both of these subjects experienced a steady decline in their resting blood pressures, day by day, during the test period. His discovery of the phenomenon that use of isometric exercise can reduce resting blood pressure was purely by chance. He has subsequently given talks on the subject, "A case of serendipity in science". Over a period of years, with the assistance of several graduate students, he researched the isometric exercise phenomenon, in a scientific manner, to establish an exercise protocol which can be used by most persons to improve their cardiovascular fitness.

Controlled Isometric Exercise to Lower B.P.
Dr. Wiley’s research at Miami University focused on two important objectives. The first was to establish that use of the controlled isometric exercise to reduce resting blood pressure would be effective and lasting, and the second was that it must be safe. Because blood pressure can rise substantially during a sustained isometric contraction, it was important to design a protocol that would not elevate blood pressures to a degree that it imposed risks to users whose resting blood pressure was already elevated (hypertension). Unlike the USAF experiments, done with healthy young pilots where studies were designed for sustained isometric exercises to the point of fatigue, the new research effort was designed to study a sequence pattern of timed isometric contractions spaced by periods of relaxation so that blood pressure elevation, during the exercise, was minimal. The question to be answered by Dr. Wiley’s new research was to determine if the repeated, smaller increases in blood pressure elicit similar changes in resting blood pressure that were realized in the high stress USAF studies. Following years of researching the endless possible combinations of parameters on a broad range of test subjects, the research yielded an exercise protocol requiring only 3 minutes of exertion, every other day.

The Key to Results
The common denominator, which was discovered by Dr. Wiley, was to establish each person’s effective isometric exercise effort relative to their own strength (Maximum Voluntary Contraction or MVC). MVC’s were measured prior to each isometric exercise by using a hand dynamometer, similar to those devised by Dr. Alexander Lind in Scotland, but subject to several generations of technological improvements. Dr. Lind also worked at WPAFB with Dr. Wiley on the evaluation of isometric exercise as applied to G-stress tolerance, and later chaired the department of Physiology at the St. Louis Universtiy Medical School. Improvements to the hand dynamometers, considered key to scientific accuracy, were implementation of electronic linear load cells to enable reproduction of actual forces applied by test subjects during experiments. Accurate Target Forces could be established with the electronic load cells as a percentage of each person’s MVC.

In earlier studies by Dr. Lind, it was determined that persons could sustain high MVC targets, such as 80%,

for only a few seconds until they reached fatigue, whereas low MVC targets, such as 20%, could be

sustained for up to 20 minutes before fatigue. Fatigue was defined as that time when the Target Force

could no longer be maintained. During these fatigue tests, blood pressures were monitored to determine

level of elevation in addition to changes in resting blood pressure of participants.

Clinical Trials

Dr. Wiley pursued a variety of isometric exercise protocols, using only a few subjects in each trial, to

evaluate the effectiveness of each protocol. In conducting these studies he implemented the exercises

in the right arm while measuring blood pressures in the left arm so that repeated measurements of

systemic blood pressure could be made without interfering with the exercise. The resulting protocol

included the use of four isometric hand grip contractions at specific Target Forces as a percentage of

each participant’s MVC, spaced by timed rest periods between contractions. It was observed that all participants using this protocol experienced reduced resting blood pressures over a period of weeks while performing the exercise a few times a week. Having identified a potentially effective exercise regimen, he modified the routine slightly to allow participants to alternately exercise the right and left hands to minimize fatigue, shorten the exercise session, and to balance the resulting increase in grip strength realized by participants over the study period. The same drop in resting blood pressures were experienced by study participants with this protocol, using alternating hands. The results of these scientific studies were published in a scientific paper in July 1992; ongoing trials are continuing this work, in other populations, for further indications.

Business Opportunity Seen
In February,1987, serendipity played another role in Dr. Wiley’s work.. Michael Smyser, then president of a company manufacturing electronic navigation equipment for aircraft and a commercial pilot, read about Dr. Wiley’s scientific work to lower blood pressure using exercise. Smyser’s daughter was attending Miami University at that time and she had published an editorial in the same school newspaper which also highlighted Dr. Wiley’s research. Having read this issue of the newspaper, the Wiley article captured Smyser’s attention, leading to a meeting at the University to discuss the research. Smyser’s interest in Wiley’s work was both personal and business. As a rated Airline Transport Pilot managing an electronics manufacturing business, Smyser could appreciate the need for a non-medical means of managing blood pressure. He understood that pilots are limited in their use of drugs to exercise pilot privileges. Also, the drug side effects of medications used for treatment of hypertension and the cost of these medications present both practical and economic incentives to bring a commercial product to market which could fill a market need for 50 million Americans diagnosed with hypertension. Smyser monitored Dr. Wiley’s progress in refining the isometric exercise protocol until 1992 when Wiley published his first scientific paper.


Business Start Up
In 1993, Michael Smyser organized an Ohio Corporation, funded and organized the U.S. patent application for Dr. Wiley’s invention. The patent was awarded on both the concept and implementation of using isometric exercises to lower resting blood pressure. The patent was awarded to Dr. Wiley in 1995 and is an asset of the company, MD Systems, Inc. located in Westerville, Ohio. MD Systems, managed by Michael Smyser as its CEO. Between 1993 and the present time, concepts of the research device used by Dr. Wiley since 1970 were implemented into a small, micro-processor controlled, battery powered device which is highly portable and can be used in virtually any location to implement the isometric exercise protocol. This device was called CardioGrip.

Medical Treatment Option
The company's CardioGrip device has obtained clearance from the Food and Drug Administration (FDA) for adjunctive use in the overall management of cardiovascular fitness. This clearance allowed physicians to use the device in their practice. MD Systems, Inc. funded further testing of the product since 1993 to collect data on the efficacy as a treatment for high blood pressure and hypertension, as a stand-alone treatment or as a supplement for drugs. These studies included patients in family practice and Phase III cardiac rehabilitation practices. Results of these tests suggest that reductions of 5mm to 30mm in blood pressure can be achieved over a period of 2 to 6 weeks. Some of those hypertensive patients using drugs were withdrawn from medications as part of the studies, which lasted over 1 year in length to prove the long-term effectiveness of the exercise treatment. The company, under the direction of Dr. Wiley, is continuing its series of scientific and medical studies of the product as a treatment for hypertension at a variety of medical schools and research institutions in the U.S. and Canada.

MD Systems' Products
A number of products utilizing electronic hand dynamometer technology developed by MD Systems, Inc. are being marketed for hand grip diagnostics, hand grip rehabilitation, and cardiovascular fitness training. In keeping with Michael Smyser’s interest in aviation, the CardioGrip device was first offered to pilots for their evaluation of its effectiveness and utility. Following a one-year study with 100 pilots using the new product, more than 90% of those who used it correctly were successful in lowering their systolic and/or diastolic blood pressures. Aviation applications for the product are considered by the company to be important as an aid to pilots in meeting current FAA AME guidelines for blood pressure limits which were reduced from 170/100mm to 155/95mm Hg early in 1997. This first public release of the product to pilots yielded suggestions for improvement in the control and display configuration which are now implemented. Use of the CardioGrip also increased grip strength by up to 20% or more, leading to a new application for the technology in hand-arm therapy. In 2002, a product called DynEx™ was developed and released for use by Occupational and Physical Therapists to diagnose and treat hand strength problems.

Product Design
The microprocessor controlled CardioGrip products are proving unique in their ability to implement the isometric exercise protocol very accurately using electronic load cell technology and interactive audible and visual guidance. Some CardioGrip models are also equipped with the ability to archive exercise data which can later be recalled and downloaded to other electronic devices. This capability was included in the design to enable medical practitioners to evaluate compliance of those prescribed to use the product for treatment. Archived data stored includes date, time, blood pressure, pulse, MVC right, MVC left, and quality of the exercise that was performed.


Copyright © 1998 MD Systems, Inc.

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