History of the World’s First Isokinetic Exerciser

THE LEAPER: HOW WE CAME TO BE

The story of our first Isokinetic Exerciser is one worth telling. I believe most business success stories originate from those who exercise their God-given talents, have patience and perseverance, and are willing to endure some hardships that usually come with a new product. I tell this story of the beginning of the small rope Mini Gym to encourage any individual who has a dream or an idea that he or she may think will sell. My advice: Don’t give up the dream! In this country, with its freedoms and opportunities (like nowhere else in this world), it only takes an idea, some sweat, and a break here or there, and you could see that dream come to fruition.

In 1967, I came in contact with a new exercise device; a small tubular unit with a rope wrapped around a steel shaft. The more the rope wrapped around the shaft, the harder it was to pull. The user pulled on one handle until the rope pulled all the way through, then pulled on the other handle until the rope pulled all the way through again. One could add more resistance by dragging the second handle across the floor. It was a simple new approach to resistive exercise, but from an engineering standpoint, it was a “Mickey Mouse” method of resistance by wrapping the rope around a shaft. However, it was selling to schools and individuals. The device was only thirty dollars and was having great success across the country. For athletic teams, usually football at the time, it was a bit of a change since most used weights or universal-type gym equipment to do their conditioning.

One advantage of our economic system is that it rewards people who improve products that they see on the market. I knew there was a more efficient way to approach exercise so I called an engineering friend named Woody Fisher. I knew that he had the “know-how” to help me design a better exercise machine. I showed him the smaller exerciser and showed him sketches of what I thought might work. I wanted to change their device and design a new unit that would change exercise programs forever. I had this wild idea but have never been one to physically do something with my own hands so I needed somebody to turn these ideas into a functioning unit. After several hours of discussion, Woody agreed to come to Independence, Missouri, and work on this new approach to exercise. I didn’t have a shop or another suitable place to experiment but my brother, Bud, had a small workshop in his basement and we began tinkering there. Within a few days, we designed the spool for a rope and braking arms, but we were a bit puzzled as how to best to return the rope from the spool for rapid repetitions until I showed Woody a window shade I had taken apart. Woody said, “I can copy that.” So he picked up some wire from a local hardware store and wound a torsion spring to install inside the spool. It worked perfectly to recoil the rope rapidly for the next rep.

It was working beyond my expectations and I couldn’t believe what we had done with so little equipment in such a short time. It was an effective exerciser that had a majority of the features I had listed. I had a speed-controlled exerciser that maintained a constant speed regardless of how hard a user worked against it. A user could do any number of repetitions at their maximum effort and as they fatigued it would adjust to them with every rep. This type of exercise had never been accomplished before and I did it with the ingenious idea of a governor braking system. For the first time in history, we had designed an exerciser that had automatic resistance in direct response to the effort applied against it. The machine accommodated to each individual’s strength output regardless of how strong or weak they were. A 10-year-old child and the strongest man in the world could use the same exerciser without making any adjustments whatsoever. They could do this for 10 reps or 100 (if they could still stand). I knew I had something excellent, but now the question was: what do I do with it now?

Since the beginning of mankind, there had been only two types of resistive exercise for improving and strengthening athletes: isotonic and isometrics. Both had their advantages and limitations but now I had discovered a third type that had advantages over the other two. It was shocking to me that this type of exercise system had not been developed yet. In only a few weeks I had designed this fantastic exerciser in a basement with just a drill press and an old lathe. We officially had a safe exerciser that permitted fast-speed resistive exercise for athletes and anybody who refrained from exercise because of the time consumption and problems associated with lifting weights. We have changed the exercise world forever with our new Isokinetic accommodating exerciser.

ISOKINETIC PRINCIPLE: The most advanced form of developing strength and power is isokinetics. When using the Leaper, resistance is always equal to the force being exerted at every angle through the full range of motion and with every fatiguing rep. If you exert 200 lbs. of effort at the beginning of a squat exercise, you’ll get 200 lbs. of resistance. If you exert 450 lbs. of effort as your legs increase leverage, you will get 400 lbs. of resistance and up to 800 lbs. in the last 2 inches of that exercise. Our governor mechanism matches the effort applied and responds instantly and automatically to the effort applied. This is perfection of resistive exercise. It responds to the user rather than the user responding like when using weights. Our Leaper is fast and safe. Athletes can work out quickly while developing more power for their game and without getting sore muscles or joints.

In the summer of 1968, an article was given to me that was published in JOHPER, the Journal of Health, Physical Education, & Recreation. This article explained a new type of exerciser that offered accommodating resistance and would measure the ranges of motion since they had a preset speed of exercise. They called the exercise “isokinetic”. This was the first time we ever heard the word “isokinetic”. Now, for the first time, we had a term for the cutting edge technology that I had developed and started selling. This new term was started by James Perrine at Iowa State University. At that time, they were selling their unit for five thousand dollars while our units were only two hundred dollars. We had been selling our units about 16 to 18 months before them, but because the ideas were somewhat similar, there was some patent litigation, but we won that lawsuit in the courts of New York.

I filed the first of our five patents and rented a 4,000-foot basement under a bicycle shop. My first production unit: The Pro, had 2 lead brake arms. Next was my Indicator model followed by the Accommodator, the first unit that hung on a wall. Next, we needed measuring so I did the Achiever, which measured the range of motion with a paper graph. Since my exerciser provided constant speed of exercise, a user would work at their maximum and the exerciser would draw out the force output for the full range of motion. This had never been done before because there was not a speed-controlled exerciser. The only way to measure muscle strength prior to this was with isometrics. However, the user was measured at only a single point in their range of motion. That was a static measurement, not a moving range of motion. My Achiever unit now drew a line of a moving range of motion. Now, muscle measurements could be graphed with exercise wasn’t possible before we did it.

Our technology had tremendous advantages because of the nature of variable human biomechanics. For example, an individual usually is twice as strong in middle range of an arm curl or knee extension as they are at the beginning or end of that movement. In a squat exercise, this variation of force output for a high school athlete may vary as much as 200 pounds of leg press strength at the beginning or bottom of a squat to maybe 600 pounds just before the knees lock out or are fully extended. Now, we can measure all these exercises but also we had an exerciser to train those extensive motions for the first time. Up to now, an athlete was always limited to the max amount of weight that they could move at their weakest point in their range of motion. These measurements also further illustrated the advantages of our isokinetic accommodating resistance.

Our new exercisers were selling with great success. We had both floor and wall models. The next challenge was to design a single unit that was a combination of a floor and wall unit. About this time, Jack LaLanne or better known as the “Godfather of Fitness” came to town to see our new exercise device. He was so impressed that he decided to help financially tool a new design that would permit exercises from the floor and yet attach to a wall for downward and outward pulls. This model was our Super Mini-Gym #180 with a force dial. Jack showed it one night on television on the Tonight Show hosted by Steve Allen giving us a lot of free publicity.

In a sense, we had turned the world of resistive exercise upside down. By the middle of the 70s, hundreds, if not thousands of universities worldwide were doing research projects in their biomechanical or kinesiology labs — or athletic trainers with their sports teams — did testing to either vindicate our Isokinetic principal or to disprove its effectiveness. Many research projects were done as thesis of masters or doctorate degrees. Without exception, every project has shown isokinetic resistance developed more strength, develop quicker reflexes, jump higher, and rehabilitate injuries more effectively in less time than other methods heretofore. This is just a partial list of those research projects on Isokinetic Exercise for testing, injury prevention, rehabilitation, comparisons to isotonic and isometrics, measurements of human performance, measuring force output, muscle strength and power, and dozens more projects.

Now, with our success, several additional companies began to design and manufacture isokinetic exercisers. Some were selling very expensive therapy units measuring ranges of motion, which provided a pathway of rehabbing all types of bone and muscle injuries. What I had invented for the industry was now succeeding big time. I was responsible for establishing a totally new industry of exercise equipment with Isokinetic Exercisers for athletic training, home exercise, measuring and rehabbing injuries of all types.

I called legendary Indiana University swim coach Doc Councilman who was always ahead of his contemporaries with his training ideas. I told him my new Leaper was completed. He had been using our small isokinetic mini gyms with his Olympic and University swimmers. His immediate comment was “How soon can you bring that Leaper over to us?” I said,“ tomorrow”. We approached Bob Knight, Indiana basketball coach, and asked to place his best player on the Leaper for the summer break. Kent Benson was an exceptionally talented player but lacked the ability to jump high enough and quick enough to control the bank board. He worked on the Leaper all summer and increased his vertical jump from 22 inches to 26 inches. He continued to use the machine and later told me he increased his vertical 9 or 10 inches. He became faster and quicker with the development of his white quick twitch muscle fibers. Doc and Bob Knight reported his summer improvement to Sports Illustrated and soon hundreds of newspapers picked up the story. That year, Indiana won the NCAA Division 1 title with Kent leading the Indiana team with an undefeated season. He made the All-American team for a second time and became the #2 rebounder in Indiana University basketball history. He also was named the Big Ten Player of the year and became the number 1 pick in the NBA the next year with the Milwaukee Bucks.

1ST LEAPER 1974

As for my basketball background, I attended Decatur High in Illinois, Graceland University, and the Air Force for a couple of years (Biggs Field). I’ve always had an interest in basketball and took college coaching classes for a future job as a high school or college coach. My concern back then with our basketball teams was a lack of exercises that actually improved our game. We did the usual running and agility drills but really did nothing to make us stronger or to jump higher. Nobody dunked the ball and there were never drills to improve our dribbling ability so that we could out-drive our opponent. Additionally, many coaches had the idea that resistive exercise would make their athletes muscle bound and too bulky to play. I was never happy with the limitations of our basketball training and was always dreaming of ways to make players play faster and jump higher. I knew we had to transfer what we had in our small mini gyms to a larger and stronger unit to develop athletic legs to their peak form. Thus, I developed our 1st Leaper and inserted a new larger governor mechanism into the frame. The first time I got under the pads and experienced the accommodating resistance for the legs, I knew this new Leaper would change the game of basketball forever.

We had proven with several thousand research projects in most universities that this new system of resistive exercise had many advantages that were never available with isotonic or isometrics exercise for both athletic improvement or rehabbing injuries. Most of our exclusive features are listed here that were never available until my advent of Isokinetic Exercisers:

1. World’s first speed controlled exerciser that had no setting of resistance as it provides automatic resistance to every person regardless of his or her strength

2. Users exercise in less time as resistance is always automatic

3. Users can do any number of reps safely

4. No spotters needed as with weights

5. First exercise system that provided full or max resistance at every point thru the full ROM, not only for that first rep but every rep thereafter as the user fatigued

6. The only method of doing fast-speed athletic training safely

7. The advent of variable exercise speed training, we could exercise both fast and slow speeds safely

Our force dial-measuring device served us through the 1980s, but when the 1990s rolled around, we knew we had to move into the next century with a more effective measuring device. We designed an LCD display for Leapers. Thus, we developed something new in isokinetic conditioning that measured an athlete’s power output through the full range of motion. Our new LCD models measure the power of each rep exercised, counts reps, provides a reading for exercise time, measures work in foot pounds of all reps, and provides an average work number for all reps done.

It has been an exciting as well as motivating journey with our 50 years of developing and perfecting our centrifugal braking exercisers. We were first in advocating “TRAIN FAST TO BE FAST” for the athlete. Now, hundreds of other companies are manufacturing some type of isokinetic exercisers. Additionally there are hundreds or thousands of fast speed training centers that develop young athletes’ power. They sell their program by developing an athlete’s explosive power for jumping higher and running faster. We continue to fill a “niche” with our Leapers and our smaller mini gym rope exercisers that do what we say they will do.

Athletes and teams can develop more power with our isokinetic exercisers — which gives them that extra edge to be a constant winner. With our variable speed governor we have the only exerciser that permits those athletes to train for both power and strength. Weights develop athletic strength but there is no way athletes can train with weights for power with Iron safely. Speed training says “Train Fast to be Fast” because it’s the most effective method of training for that explosive power with our Isokinetic Leapers and our rope mini gym exercisers.

We have recently designed a new Family Mini Gym that only weighs 12 pounds that is ideal for most families who want to exercise in their own home, even watching TV if they wish. This small ISOKINETIC Family exerciser solves the problem for the home-body who can’t go to health clubs since it permits dozens of exercises from the floor and attaching a wall bracket in a rec room permits many more exercises. With our new FAMILY MINI GYM, members of the family can do the HIT exercise for cardiovascular and with turning the speed control to slow provides muscle toning and strength gains safely. In addition, this new unit also serves the young athletes in the family to train for jumping higher and developing quickness that weight training can’t do. This unit will be available to area distributors for resale to others. Call us here at our office for more information on this program.

- Glen E. Henson, Founder

This success created a new approach of training fast-speed resistive exercise and the word was out to high school coaches. Many schools purchased the Leaper and saw so much improvement with their players that many opposing coaches would call us and ask how soon they could get one of those “things”. Some would say, “Just played a team and got our tail beat. I can’t believe the difference between last year’s and their team this year. Last year we beat them badly, but their players improved so much, we’ll never beat them again. They tell me they got a Leaper. How soon can I get one of those ‘things’?” Virtually every high school and university purchased our leaper in 1970’s and 80’s and we could not manufacture them fast enough. Fast-speed resistive exercise had made inroads for the first time with basketball teams and since has spread to most athletic sports. Many older basketball coaches give the Leaper credit for revolutionizing the quickness of player’s reflexes and the dunking that exists today. The Leaper provided a way for basketball and volleyball teams to work fast and safely. The Leaper changed basketball and volleyball coaches’ attitude of fast speed resistive exercise, which was not possible prior to the advent of isokinetic resistance.

The next opportunity emerged when we sold a couple of units to Harding College in Searcy, Arkansas. Professor, Dr. Orlee was so impressed with our isokinetic exerciser that he contacted Dr. Rummel of NASA to consider the Mini-Gym for space flights. The NASA engineer for this type of equipment was John Lem, who would later write articles on the Super Mini-Gym.  John came to our plant a couple of times to get a mini gym ready for the space environment. Dr. Rummel was in charge of the astronauts exercise programs. He began a crash exercise program to remedy the astronauts’ loss of muscle experienced during their first two flights since the next flight was to be extended to sixty days. This next crew of astronauts took their Super Mini-Gym with the other supplies in their spaceship from Cape Canaveral and transferred them to Skylab which was already circling the Earth. The crew of Skylab 3, Bean, Garriot, and Lousma, worked diligently on the Super Mini-Gym daily for the sixty-day flight. They returned to earth in much better shape than the crew of Skylab 2. The crew of this 3rd flight was on worldwide television using the Super Mini-Gym and praising it. (See our video on YouTube). They called the unit “Mark I”. It was so effective for them, the continuing flights used it, and the Super Mini-Gym 180 had made its debut.

Because our new exerciser permits fast speed resistive exercise, we now develop athletes with white quick twitch muscle fibers for more explosive actions such as jumping higher with much more speed in running etc. This HIIT training now is done safely and in less training time — just not safe to do with usual weight training. In addition to athletic training, we now can offer this safe exercise to adults as recent research show that but 10 minutes exercise 3 times per week with our HIIT exercise can be comparable to 50 minutes of exercising with weights. Click to read research articles from Time Magazine and doctors at Mayo Clinic.

By 1974 we developed several other applications from the basic Mini-Gym such as the Leaper, Swim bench, and Knee Unit. We had tremendous success with many athletes and teams, including Bruce Jenner, Mark Spitz, and Kent Benson. Most colleges and universities as well as several pro teams also used Mini-Gym equipment. The isokinetic principle had proven itself by developing more strength, athletes jumping higher and rehabilitating injuries quicker and easier.