An isometric exercise is one in which force is generated without any joint movement or change in muscle length while that muscle is under tension.

An isotonic exercise involves the joint moving and the muscle shortening as the tension varies within the movement.

The image below shows a simple isometric movement.

The plank is an isometric movement familiar to most people who are into fitness and home workouts. The position is similar to that of a push-up, with your body in straight alignment. Holding such a position involves the core muscles and may improve posture. It also may be helpful in eliminating back pain.

The strict plank position may be held for 30 seconds for beginners and then longer with practice. Advice on lengths of hold times varies. Some may hold for 2 to 4 minutes, though many suggest limiting this to one minute and doing multiple sets. In the Guiness Book of World Records, someone held a plank for 8 hours.

Suffice it to say that isometric exercise can be quite productive and that the plank is one of the better examples of isometrics. See the image below.

Charles Atlas was the first famous “strong man” that I can recall. He promoted an exercise system that he called “Dynamic Tension”. He said “My system uses no apparatus. The resistance of your body is the best and safest apparatus”. This sounds somewhat like isometrics, but the Charles Atlas exercises involved movement of the joints, so were not isometrics. They, however, might have been easily adapted to isometric forms.


I have been working out at home for decades. Before then, I visited gyms and Nautilus centers. Before the gyms, I worked out with barbells in a garage at age 18 and 19.

With self quarantining, my home workouts have become the best part of my day. I am dealing with a rotator cuff impingement in my right shoulder, with lots of arthritis. This has limited what I can do, though it still leaves me with plenty of viable forms of exercise. I initially had several weeks of physical therapy to increase my range of motion on the right side. My current routine each week is:

  • Monday, Wednesday, Friday – 30 minutes on my treadmill, escalating the speed every minute
  • Tuesday, Thursday, Saturday – 30 sets of remedial / bodybuilding exercises. This includes 12 therapy stretches and 18 bodybuilding sets
  • Sunday – rest, except walking outside

The 18 bodybuilding sets began at only 8 up to a few days ago. These were:

  • 2 sets – seated twisting, side to side, facing forward. This was for the external oblique core muscles, sometimes called love handles. 100 reps per set.
  • 2 sets – V-ups, 30 reps per set. See image below. Begin with hands straight behind head and legs straight and flat on surface. Great abdominal exercise!

  • 2 sets – heel raises for calves. 50 reps per set, with hands against a wall and feet 3-4 ft. back
  • 1 set – lat pull with resistance cords anchored at door. 30 reps, pulling to sides and graduating slowly from low to high part of torso.
  • 1 set – triceps “kickback’ with resistance cords also anchored at door. This engages triceps as the cords are pulled back by straightening arms at the elbows. 40 reps.

This routine was okay and seemed the best I could manage with my rotator cuff injury. There was a problem – I was doing nothing for my chest, biceps or shoulders. This was because my therapists had strongly advised against any pushing or pressing movements until my shoulder was well. Also, curls for the biceps were discouraged.

I was finally able to add 10 more sets for the unworked body parts by adding isometric holds, with Bullworker products.


I had been using Bullworker products for a couple of years. They are especially valuable to me for these reasons:

  • The products are well-made and challenging
  • They are relatively small and portable
  • There are 3 resistance levels, with interchangeable springs
  • Handbooks are included with each product to give precise guidance on their use
  • A Facebook group is available for questions / answers and encouragement to all users
  • The Bullworkers provide both isometric and isotonic forms of strength building

The Bullworker Bow Classic is shown below. The Steel Bow is shorter, but otherwise quite similar. I have both.

The exercise below is the “archer”, which engages the latissimus dorsi muscles of the back. The grips may be pulled apart, as shown, or the red handles may be compressed. The resistance is always provided by the spring within the steel tube.

The isotonic aspect is the pulling apart or compressing. The isometric part is the lengthy static “hold” at the end or beginning. Some users do an isometric hold at the beginning (for about 10 seconds) and then proceed with about 10 isotonic reps. I always preferred to do the reps first and to wind up with the hold at the end.

Still others only do the isometric hold. I had never used Bullworkers in this manner, until I had an epiphany:

  • Doing isometric static holds would be the answer to my dilemma – how I could incorporate chest, biceps and shoulder exercises without unduly stressing my injured shoulder.
  • So I added chest compression holds, cable spreads and a few other holds to my routine – nothing but tension created by static holds, often for 20 – 30 seconds.
  • This has provided a good “pump” and has not been at all injurious to my right shoulder. Thus, my Tuesday / Thursday / Saturday workouts now include 30 total sets. The pace for the routine is fast and productive.


For full information on the Bullworker product line and their training philosophy, check here. For any purchases, add the coupon code HAT 5 for a 5% discount.


We all travel differing paths to reach our fitness goals. Hopefully, some of my experiences may be at times aligned with others who read this.

Before I forget, let me provide the most current link to my favorite sporting goods supplier and the largest such merchant in the United States, Dick’s Sporting Goods. I have purchased from them for decades and find their product quality and service to be exceptional. Check for their discounts by the link below. They change weekly.

Save Up To 50% On This Week’s Deals at Dick’s Sporting Goods

Please leave me any questions or comments in the “Comments” box below. Or email me, richard@myworkoutathome.com.

Be well and alert!


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