My first experience with moving Isometrics was Boxer's using it in the 1950's, Boxer's being trained by a uncle. Then later discovered the Dynaflex Course from Mike Marvel, a book with cartoons on how to use the exercises.

Bob50 yeah dumbbells works, and I've read early strong men used light dumbbells and muscular resistance, I suspect resistance is resistance to the body. The only thing that counts is results and good health.

Just sounds confusing and doesn't make sense. But to each his own.

"How does dumbbells restrict the involvement of muscle fibers in voluntary movement? How are we limited by the gravity vector?"

Factually, you answered these questions yourself: "... VRT and isometrics can be trained at different angles."

If we use dumbbells, we need to adjust the positions of our limbs and body to develop different muscle fibers. Sometimes, it is difficult or impossible to do. Also, we know that some muscles fibers cannot be trained successfully, using only gravity. However, as I have written above, different people have different opinions.

P.S. Not everyone performs hard physical work daily; therefore, harmonious development of different muscles/muscle fibers may be important for many people.

How does dumbbells restrict the involvement of muscle fibers in voluntary movement? How are we limited by the gravity vector? Sorry but this doesn't make sense to me.

Don't all movements we do in everyday life involve muscle fibers? I believe every kind of training and movement uses muscle fibers. Some in more different ways than others? I know when I'm lowering a big log on a rope out of a tree I feel my muscles burning in my forearms, which is because of gravity.

Voluntary muscles are the ones you can control which move your bones around. No scientist but everything we do moves our bones around.

You right self resistance, VRT and isometrics can be trained at different angles.

Do we really need the light dumbbells for VRT/DVR/co-contraction exercises? It seems to me, any dumbbells restrict the involvement of muscle fibers in voluntary movements because we are limited by the gravity vector. The delight of any self-resistance exercises is their versatility, capability to train any muscles under any angles, moving on any trajectories, and to use any needed muscle tension in any point. I agree that for beginners, the dumbbells could help to concentrate their attention, but later they become the break. However, it is only my personal opinion. As Michael frequently mentions "we are all different" and someone may have different view.

Long ago once saw dumbbells from the late 1800's in a collection and was surprised how light some were.

Thanks for posting that article MikeNY. Just realise that that was a course of him showing the exercises. Who knows how many pounds those dumbbells were but they were just for demonstrating purpose. My 5 lb dumbbells look the same as those in the picture.

Attaced is an article on Sandow's Training https://physicalculturestudy.com/2015/09/08/train-like-a-sandow/ it shows him using dumbbells. I've read he used 5 to 10 pound dumbbells; the dumbbells apppear light, like 2 lbs.

I agree, Michael, isometrics and VRT are different "animals."

What you guys are doing is great. But my only thing is Iso is without movement. What you guys are talking about is not Isometrics. They also are not Power Flexing. Flexing is what bodybuilders do when they pose. They flex hard and hold it. Then they move to a different pose. The Flexing itself is done without movement. Again I am not criticising what you guys are doing just saying isometrics is without movement. I actually commend you guys for staying in the game.

As I have written before, I could consider Iso-VRT only as keeping a constant level of muscle tension through the full ROM. Of course, it is possible only if we use any kind of self-resistance. But I also would avoid this name to exclude the confusion.

MikeNY for the light dumbbell exercises Sandow used I read he used 7-10 lbs.

By the way, what do you guys mean by considered"trained" then " non-athletes"? This all sounds more confusing then need be. I still don't get how can someone consider movement isometrics. Just like when someone says iso dynamic it just doesn't make any sense. This is just confusing, especially to new people to this way of training. But anyhow, there are many ways to do this stuff.

In Ellington Darden's book on 30/30/30 he notes and teachs 20/20/20 (20 seconds negitive, 20 positive & 20 negitive and they uesd one rep ). PLus if you check photo's of Sandow; his dumbbells appear very light my guess is 2 lbs. or less; and many early weightlifter's used internal resistance.

Great reply Bob50, I also think for older folks self-resistance/VRT and using a stick works as well as weight lifting! As a teen in the 1960's I had an expensive weight set and used it; but stopped and preferred Isometrics (using an Isometric Exerciser) and VRT alone or using a faux barbell staff.

Mike,

I think that people who have experience in any voluntary muscle tension fall in the category of trained. As you have seen in the paper, the regular training increases the capability to tense muscle antagonists, and thus, the muscles gradually get progressive loading. As a results, we can gradually gain both muscle mass and strength. Probably, self-resistance/co-contraction exercises are not so effective as weightlifting, but for older people, like we, this training is a great and safe way to be fitted for all rest life.

I use VRT/co-contraction as the main method of training for several years. Plus sometimes, I use a stick for self-resistance exercises. I believe that these exercises daily help me to keep a good physique. I apply considerable muscle tension but avoid long holding (> 5-6 sec) to prevent the increase of my blood pressure. Maybe 30/30/30 is a good protocol, but I would not like to risk if the shorter holding works successfully. I do not want to be supper, I just want to be good.

Bob50 but are not those that train using VRT/Atlas Isometric Weigtlifting considered "trained" rather then "nonathletes"?

Bob50 have you trained using VRT? What were your results? Ellington Darden writes about superslow, and now teaches 30/30/30 and writes how it is proven that negitive training improvrd results. VRT is just muscle resistance.

I think this paper is interesting to re-read to understand the efficiency and limitations of VRT training

http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0079486

Abstract

Antagonistic muscle pairs cannot be fully activated simultaneously, even with maximal effort, under conditions of voluntary co-contraction, and their muscular activity levels are always below those during agonist contraction with maximal voluntary effort (MVE). Whether the muscular activity level during the task has trainability remains unclear. The present study examined this issue by comparing the muscular activity level during maximal voluntary co-contraction for highly experienced bodybuilders, who frequently perform voluntary co-contraction in their training programs, with that for untrained individuals (nonathletes). The electromyograms (EMGs) of biceps brachii and triceps brachii muscles during maximal voluntary co-contraction of elbow flexors and extensors were recorded in 11 male bodybuilders and 10 nonathletes, and normalized to the values obtained during the MVE of agonist contraction for each of the corresponding muscles (% EMGMVE). The involuntary coactivation level in antagonist muscle during the MVE of agonist contraction was also calculated. In both muscles, % EMGMVE values during the co-contraction task for bodybuilders were significantly higher (P<0.01) than those for nonathletes (biceps brachii: 66±14% in bodybuilders vs. 46±13% in nonathletes, triceps brachii: 74±16% vs. 57±9%). There was a significant positive correlation between a length of bodybuilding experience and muscular activity level during the co-contraction task (r = 0.653, P = 0.03). Involuntary antagonist coactivation level during MVE of agonist contraction was not different between the two groups. The current result indicates that long-term participation in voluntary co-contraction training progressively enhances muscular activity during maximal voluntary co-contraction.

It works for all of us, great thing. I still love regular speed VRT!

I disagree but that's ok as long as it's working for You.

I think that VRT is an Isometric Power Flex exercise!

Bob50 for me super slow is 10 seconds negitive and 5 seconds positive, Isometric means to me movement under tension, no real weights or even a wooden staff, just isometric power with movement. I think movemnt under tension limits reps to 10 or 12 reps for one set.

MichaelS I use to use Atlas Isometric Weightlifting/VRT are normal speed as outlined in VRT! Super slow means less reps and sets. MichaelS I see super slow isometric movement as a form of powerflex!

MikeNY, were You doing VRT differant before? If so what results have You seen from Slower VRT? Don't think I'm trying to rain on Your parade but Super Slow and isometric are differant. Isometric is without movement. Power Flexes are a form of isometric but moving slower or super slow is not. Are You doing Power Flexes at the end of Your movements? If so how long are You holding them?

Mike, please answer my stupid question, what means "isometric" if we are talking about super slow reps (super slow movements). Is it the holding some isometric level of muscle tension during super slow movement?

If so, I used super-slow movements with continuous holding the isometric level of tension through the full set, but I did not find extra benefits. Then I switched back to normal/slow movements ( 4-6 sec concentric and 4-6 sec eccentric). I feel that this time is enough for me to unite feeling, visualization, tension, and movement. 6-8 sets x 10-15 reps for each muscle group is good loading for me.