People say "I need to lose weight." What they mean, of course, is they need to lose body fat.
Losing weight is a really bad idea if the weight lost is muscle, which is active tissue that burns calories. Body fat doesn't burn calories, it just sits there. A loss of muscle mass while dieting can cause a cascade of ill effects.
Dieting that restricts caloric intake invariably leads to a loss of muscle mass, which is the active tissue in the body that is burning most of the calories consumed. If you keep losing muscle due to dieting, you will keep getting fatter.
Some believe exercise will prevent this muscle loss, but expending more calories while the body is already in a calorie deficit from dieting only causes severe hunger pangs and the consumption of extra calories to replace those lost during exercise. It's a zero-sum game.
So the question becomes: How do you lose body fat without losing muscle or becoming hungry from exercise?
Pregnant women often find themselves in a calorie deficit because the developing fetus requires a lot of extra calories that may not be readily available (no food at hand). So the human body does a wonderful thing: It produces a complex amino-peptide molecule that regulates the metabolism of body fat.
This is the same molecule that a pregnancy test detects the presence of in the urine.
Dr. Simeons in 1956 made the discovery that a small amount of this molecule in the blood stream while on a calorie restricted diet allows the body to comfortably burn body fat without loss of muscle mass or hunger.
He spent decades perfecting his diet protocol and published the book Pounds and Inches: A New Approach to Obesity.
Since long-duration exercise does not preserve muscle mass and causes cravings for more calories, what type of exercise is most effective at preserving muscle while dieting?
Isometric Exercise Studies
All out maximum isometric effort in the most efficient joint angles for producing maximum force expose your body to incredibly high loads. Higher loads lead to greater strength and neurological efficiency improvements.
In a 2017 paper by Jenkins et al titled Greater Neurological Adaptations Following High- vs. Low-Load Resistance Training, neuromuscular adaptations were studied following three and six weeks of 80% vs. 30% one repetition maximum dynamic resistance training to failure in leg extensors. It was found that despite similar increases in muscle thickness, strength improvement was much greater in the high load group. This group also exhibited a significantly higher increase in the ability to voluntarily activate musculature while the low load group had almost no change.
Again, maximum isometric effort performed in your most efficient joint angles exposes you to the highest loads possible. It also leads to even greater changes in neurological efficiency.
In a 2001 paper by Babault et al titled Activation of Human Quadriceps Femoris During Isometric, Concentric, and Eccentric Contractions, it was shown that voluntary activation during isometric contraction was far greater than concentric or eccentric contractions (eccentric being the lowest for all those fans of heavy negatives).
But there is something else happening here that makes the case stronger.
In the Jenkins study another hypothesis was also tested: If high-load training improves neurological efficiency better than low-load training, when working at submaximal force levels a smaller proportion of strength should be used.
That is exactly what happened. Voluntary activation actually went down significantly in the high load group with little change in the low load group. This indicates greater efficiency from high load training.
In other words, you are able to exert the forces you need but with less neuromuscular activity. You are able to do more with less. This makes perfect sense. In nature you don't adapt to expend more, you adapt to expend less. This is why everything you do becomes easier.
With measured isometrics you have the ability to measure and safely expose your body to the highest loads possible in just a few seconds. This improves your neurological efficiency. This gives you greater strength increases. This makes everything you do less taxing. Isn't greater strength why people lift all those weights?
So, if isometrics expose your body to the highest loads AND yield much larger changes in voluntary activation AND yield much larger increases in strength AND provide greater neurological efficiency improvement AND it only takes a few seconds to get these benefits why is there a need to make weights go up and down and age your joints in fast forward, while expending a lot of calories you'll need to replace?
There isn't.