Endurance Fitness Training: Keeping The Mitochondria Furnaces Burning

Senior couple in gym working out, doing push ups | Endurance Fitness Training: Keeping The Mitochondria Furnaces Burning | what is endurance training | Featured
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How can enhancing endurance fitness help improve your overall health? Keep reading and find out here!

RELATED: Memory Loss and Exercise

In this article:

  1. Building Endurance and Strength Through Routine Workouts
  2. What Are the Effects of Endurance Training on the Mitochondria of Muscle Cells?
  3. Benefits of Building Muscle Endurance
  4. How to Build Muscle Endurance

How Endurance Fitness Affects Your Cells

Building Endurance and Strength Through Routine Workouts

What immediately comes to mind when someone mentions exercise? Guilt perhaps?

Or maybe rationalizing? (I’m still pretty healthy even though I don’t exercise. A lot of my friends don’t exercise and they seem healthy.)

Of course, not everyone should run miles at a time like endurance athletes do, or lift massive weights. But, there is compelling evidence to support the significant health benefits, both physical and mental, of a daily regimen of exercise appropriate for you and your endurance fitness level.

“There is compelling evidence to support the significant health benefits of exercise.”

One form of exercise, endurance training, was the subject of a recent study at the Howard Hughes Medical Institute (HHMI) laboratory, located at Yale University School of Medicine.

For decades, scientists have known that physical activity like running and swimming, which increases heart rate and breathing, results in significant physiological changes or adaptations to improve muscle function and endurance fitness. For the first time with living human subjects, research demonstrated another beneficial effect of this type of exercise.

What is muscular endurance? This kind of exercise trains muscles to exert force against itself to develop resistance and the ability to recover from and develop immunity to trauma.

What Are the Effects of Endurance Training on the Mitochondria of Muscle Cells?

Senior man in gym working out with weights | Endurance Fitness Training: Keeping The Mitochondria Furnaces Burning | training for muscle endurance can be done with

That is an important question which scientists have only recently answered. Prior to that, scientists knew that with endurance training, changes in muscle tissue might include increased production of new blood vessels and greater capacity of cells to store energy.

Endurance interval training also increases sensitivity to insulin so that glucose, as fuel, can enter cells more readily. All of these changes are directed toward improving the delivery of nutrients and fuel to satisfy the increased energy demands of the exercising muscle.

Beyond better fuel delivery, earlier animal and in vitro (cell culture) studies revealed something intriguing—an increased capacity of the cells which comprise the working muscles to burn fuel, especially fat, and thus to convert that fuel into energy.

In addition to that, endurance-conditioned cells continue to burn fuel, including fat—even when at rest. But why?

Chain Reaction

“Exercise that increases heart rate and breathing results in improved muscle function.”

Exercise initiates a series of complex biochemical events in the muscle cells.

One of these, the production of a substance known as 5′ AMP-activated protein kinase (AMPK), activates a cellular tool called PGC-1 alpha. This tool, in turn, enters the control center of the cell, the nucleus, where it homes in on the on/off switches of specific genes to turn them on.

The activated genes produce proteins required to construct new fuel-burning organelles, the mitochondria.

What is the mitochondria? This is the part of the cell where energy production and respiration occur.

This explains why, as earlier research had shown, muscle cells isolated from an endurance-trained animal had a greater capacity to produce energy than cells isolated from a sedentary counterpart.

Simply put, more exercise produced more mitochondria/cell “furnaces” for more energy to make the exercise easier. The effects of endurance training on the mitochondria of muscle cells were clearly beneficial.

Animals to Humans

The early studies laid the groundwork for the team at the HHMI lab at Yale. They wanted to determine whether the same or similar changes occurred with humans, in particular, the effect endurance exercise has on the mitochondria in our skeletal muscle.

Faced with difficulties in applying the same techniques used with animals and cultured cells, the investigators realized a newly developed, non-invasive tool could yield similar information if applied to humans.

MRS Technology

“Do endurance-conditioned cells continue to burn fuel even at rest?”

The technique involved using a magnetic resonance spectrometer (MRS). This technology can accurately measure the amount of a nutrient containing a tag (13C-acetate) that is metabolized in the energy-producing cycle (the Krebs cycle or TCA cycle).

Two groups of human subjects were chosen for the study. Seven healthy males of normal weight who exercised in running-based sports a minimum of four hours a week were in one group.

The second group included eight males of similar age, weight, and overall health, but who did not participate in endurance training. Both groups were injected with the 13C-acetate nutrient.

After a fixed period of time and under non-working (resting) conditions, the muscle of the right calf was scanned with the MRS instrument.

Because the 13C-acetate is essentially converted to substances that are burned as fuel, the scans provided the investigators with information on the rate at which the tag was being metabolized (oxidized into other compounds during the production of energy) in the cell’s mitochondria.

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Benefits of Building Muscle Endurance

Fit senior sporty couple working out together at gym | Endurance Fitness Training: Keeping The Mitochondria Furnaces Burning | strength endurance training

The muscle endurance study resulted in identifying its various benefits to the human body. Some observations included more calories burned and more fat processed by the body.

While not much difference could be seen between the two groups at rest, a stark difference can be found in the mitochondrial level. Check out the benefits when you build muscle endurance and enhance endurance fitness.

1. More Fuel Burned Without More Work

The results showed 54% more fuel burned in the TCA cycle in the endurance-trained group as compared to sedentary controls.

Interestingly, this burned fuel did not represent an increase in the production of ATP, the cellular chemical utilized by the muscle to do work (contract muscle). The amount of measured ATP in both groups was virtually identical.

“The innovative HHMI experiments used a magnetic resonance spectrometer.”

On the one hand, this is not too surprising as the measurements were taken at rest, when little muscle contraction is occurring and, therefore, little of the energy molecule, ATP, is necessary. But, on the other hand, the normal coupled reaction between fuel-burning and ATP production seems to have been disrupted in the endurance-trained subjects.

In other words, the muscle of the endurance-trained group was still burning more calories (released as heat and not converted to ATP), even while at rest.

2. Cutting Out Fat

A modern man/woman is exposed to excessive amounts of energy-rich foods. As a consequence, we are more likely to develop diabetes, heart disease, and other age-related conditions.

Previous animal and cell-culture studies have shown that exercise improves insulin sensitivity, guarding against insulin resistance, the precursor to diabetes. The recent HHMI research gives us even more insight into the potential long-lasting effects and benefits of exercise, specifically in relation to the fat-laden cells, including muscle cells, that have been associated with many health concerns.

Muscle endurance exercise, as demonstrated by the Yale team, activates cellular tools. They, in turn, increase the production of the cellular fuel-burning machinery (mitochondria) necessary to remove excess fat from cells, even while we sleep.

3. More Energy for More Activities

By burning more excess fat from cells, people with more muscle strength and endurance produce more energy to use. This means they can do more repetitions during workout sessions and even lift heavy weights more efficiently to improve endurance fitness.

This also gives you more energy for daily activities like lifting heavy objects or even going up and down the stairs. You can do more work longer without worrying about falling sick or feeling fatigued.

How to Build Muscle Endurance

Older man lifting weights, supervised by gym assistant | Endurance Fitness Training: Keeping The Mitochondria Furnaces Burning | endurance training program

Though the control group was injected with the 13C-acetate nutrient for purposes of the study, you can still build up muscle endurance through following one of several training plans.

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1. Enroll in an Endurance Training Program

You can enroll in a training program that focuses on weight training in a fitness club, so you can build your endurance guided by a fitness coach or personal trainer.

Weight training, also known as resistance training, focuses on working a particular group of muscles to enhance its endurance fitness. It stretches, pulls, pushes, flexes, and extends the connective tissues in the muscles to strengthen them.

To do this, you’ll use fitness equipment like a kettlebell, weights, free weights, heavy weights, and other weight machines. You will also utilize resistance bands or tubes.

2. Try Circuit Training

If you want to work on improving your muscle endurance fitness at home, you can use your own body weight to work out. Try circuit training to build both muscle and cardiovascular endurance.

Each major muscle group should be trained two to three times a week using intervals of various machines or equipment. You should rest for 48 hours between resistance training sessions to let the muscles heal.

Building strength in the muscles also keeps bones dense and strong, lowering the risk of injuries to the musculoskeletal system.

3. Do Sit-ups

This muscle endurance exercise can train your muscles in the abdominal area by lifting your upper body weight repeatedly. Follow these steps to do this training for endurance properly:

  • Lie on your back. Bend your knees and keep your feet flat on the floor.
  • Position your hands behind your neck while your elbows extend sideways.
  • Clench your abdominal muscles and start to bring up your torso. Make sure you’re using your abdominal muscles to bring your body up.
  • Bring your body down, still using your abdominal muscles.
  • Do five sets with 25 reps each.

Tip: You can use a yoga mat to prevent your tailbone from rubbing against the ground and improve performance.

4. Perform Push-ups

Push-ups primarily help strengthen your deltoids, triceps, and chest. These are three major upper body muscles which aid in strengthening your endurance fitness.

Follow these steps to perform this personal training:

  • Lie on your stomach.
  • Start pushing your body up to a plank position using your hands and toes.
  • Lower your body until your chest touches the ground, then push back up. This makes one count.
  • Do five sets with 10-15 reps. Gradually increase the number of your push-ups as training days go on.

5. Execute Walking Lunges

Walking lunges help improve the hip flexor muscles which tend to become stiff or tight because of an inactive lifestyle. Do the following steps to perform this physical fitness exercise:

  • Stand with your feet shoulder-width apart.
  • Use one leg to take a forward step.
  • Drop your body down, making sure your legs form 90-degree angles.
  • Push down using your front heel and then go back to standing position.
  • Repeat the same steps with your other leg.
  • Do five sets with 15 reps each on one leg. Do the same on the other leg (equaling to 30 lunges each set).

6. Do Squats

Mature Senior Man Exercising Doing Squats | Endurance Fitness Training: Keeping The Mitochondria Furnaces Burning | muscle endurance exercise

Squats help promote body-wide muscle building as it enhances your butt, lower back, abdominal muscles, calves, hamstrings, and quadriceps. They also strengthen the muscles in these areas.

Follow these steps to do this strength endurance training:

  • Stand with your feet distanced wider than shoulder-width and toes pointing straight.
  • Bend your legs and make sure your buttocks are on the same level as your knees. Your legs should be in a 90-degree angle.
  • Push your body back up, squeezing through your glutes.
  • Do five sets with 25 reps each.

Enhancing endurance fitness by performing muscular endurance exercises. They benefit the body from deep within the cells, making you feel and look better.

Make sure you do the endurance workouts properly to avoid injuries and to maximize the benefits on your muscles.

Support your endurance fitness training with an energy boosting dietary supplement. Juvenon Energy Boosting Formula is supercharged with 12 natural ingredients bound to sustain your body’s energy so you can train better and longer.

Are you building your muscular endurance now? Which endurance training exercises are you following? Tell us how it improved your overall health in the comments section below!

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A group of investigators from a number of Pacific institutions recently published, “FOXO3A genotype is strongly associated with human longevity,” in the Proceedings of the National Academy of Sciences (PNAS). They reported on their findings regarding a specific genetic variation of FOXO3A.

This gene was investigated as a possible link to human aging based on previous work with lower forms of life (worm and fly), which identified a gene that, when mutated, seemed to confer longer life on the organism. The longevity-associated gene is involved in the regulation of insulin signaling pathways. Known as DAF-16 in the worm C. elegans, it is the counterpart of the human gene, FOXO3A, also associated with metabolic pathways regulated by insulin signals.

The investigators hypothesized a correlation between a similar mutation in the human FOXO3A gene and longevity in humans. They set out to test their theory by examining the frequency of a mutation in FOXO3A in a population of Japanese-American men living in Hawaii.

The subjects were divided into two pools, those who died before the age of 81, mean age 79 years (402 subjects), and those who lived 95 years or longer (213 subjects). Genetic material (DNA) was extracted from the blood cells of both groups and the FOXO3A gene was examined for specific genetic variation (mutations known as SNP).

The results of the gene analysis established a strong association between a specific SNP and longevity. This would seem to indicate that, like the worm and fly genes, the FOXO3A gene is, at least partially, responsible for longer life.

This Research Update column highlights articles related to recent scientific inquiry into the process of human aging. It is not intended to promote any specific ingredient, regimen, or use and should not be construed as evidence of the safety, effectiveness, or intended uses of the Juvenon product. The Juvenon label should be consulted for intended uses and appropriate directions for use of the product.


Dr. Treadwell answers your questions about Juvenon™ Cellular Health Supplement

Question: A friend claims that many people don’t even digest vitamins and that chewing up vitamins or using liquid vitamins is the only way to have effective delivery. This is his claim but I know of no data to support it. What is the most effective way to take Juvenon and other examples of Dr. Bruce Ames’ supplements?– D

Answer: Some people may find that taking vitamins in liquid form is more effective than tablet form. However, in general, tablets dissolve readily and should be absorbed as well, or almost as well, as a liquid. I suggest taking the tablets with water or juice. If you find it difficult to swallow a tablet, try taking it with a thicker drink, such as low-sodium tomato juice, or a food such as a yogurt.

Benjamin V. Treadwell, Ph.D., is a former Harvard Medical School associate professor.

Editor’s Note: This post was originally published on July 12, 2019, and has been updated for quality and relevancy.