Connect with us



By Daniel Gwartney, MD

People eat too much. Oops, the truth spilled out. There are far too many calories consumed by the general population, and laborious effort has been trimmed to the bare minimum in many people’s lives. Compound that with the decline in active recreation (e.g., exercise, sports), and the cumulative effect over time is… where we are as a society now. There are nearly twice as many overweight and obese people as normal weight.

People are educated about calories, and want to reduce how much they take in. They still want to enjoy the flavor and experience of eating, just in a way that is consequence free. Further, the interest and benefits of reducing carbohydrate intake – especially sugar – has allowed the sugar substitute industry to enjoy a healthy market demand. Sugar substitutes are also called non-caloric artificial sweeteners (NCAS), though certain ones do contain a caloric value. There is a long history of NCAS use, with the first commercial product, saccharin, discovered more than 100 years ago. Currently, there are a handful approved for use in the United States, more familiar by their brand names (e.g., Sweet’N Low, Splenda, Equal). Most NCAS are chemically synthesized, though plant-extract stevia products are also available.

The premise is logical – replace sugar and its simple carbohydrate calories with a substitute that provides the same taste (sweetness) but lacks calories. Genius! Nature OUTSMARTED… not. Recall, the golden years of sugar substitutes occurred DURING the obesity crisis that continues unabated today. Society as a whole did not enjoy weight loss, or even a prevention of further weight gain, with the availability of “non-caloric artificial sweeteners.” IT GOT WORSE. Individually though, did people who used artificially sweetened products lose weight? Certainly, they must have since they were not consuming as much sugar or calories, right? Umm, maybe not… probably not… well, no, not really.

The Body’s Response

A scientific review considered the use of NCAS and weight management.1 The authors attempted to clarify one area of confusion – that being, do people who use NCAS make up the calories in later meals? Well, there is conflicting evidence, but cutting to the chase, people don’t take in enough calories later on to make up for the calories they avoid from sugar by using NCAS. Not a whopping amount, as it results in maybe a half pound of weight loss per week based upon the calorie deficit. Of course, that assumes that the calories lost by substituting with NCAS actually make the diet hypocaloric. The review noted that NCAS consumers are generally people with a higher BMI, suggesting the calorie content of their diet is above their maintenance needs. So, with NCAS use, they are consuming fewer calories, but still too many. Perhaps gaining weight at a slower pace could be given and “honorable mention” award.

Researchers have rightly noted that NCAS are not just “sugar substitutes,” but chemicals that may have effects on various tissues, such as the intestines and brain.2 One aspect questioned is the “enteral-brain axis” or gut-to-brain communication. When you taste something sweet, but don’t get the increase in blood sugar and calorie availability, insulin release and suppression of fatty acid release that your brain expects from sugar – how does the body respond? It is confused, as sweet on the tongue should result in an influx of simple sugars that stimulate insulin release and begin to satisfy the appetite. Instead, it may lead to a greater demand for eating, as the body is told there is nutrition coming by the tongue, but not seeing it as available calories. Though the data is sometimes conflicting, it also seems that the intense sweetness triggers the “reward” pathways in the brain, and in susceptible individuals this results in bigger meals or more frequent food-seeking behavior (e.g., snacking).2,3

Bear in mind, the “five senses” – sight, smell, sound, touch and taste – are the brain’s direct connection with the environment. If the brain senses food by sight, taste or smell, it generates hunger and turns on behavior “programs” that result in eating. Fast-food restaurants know this, which is why they have brilliantly lit marquee signs and pipe the smell of french fries into the exhaust vents to be inhaled by drivers passing by. The sweet taste of sugary icings is what drives most to eat doughnuts, not the cake. Now, imagine if you smelled french fries, and the aroma was coming from an auto parts store. You don’t forget your hunger; you go looking for a nearby McDonald’s. If your brain tastes sugar, and it gets saccharin or aspartame, it sends you off to find food.4

The NCAS industry hasn’t been bothered by this, though, as people have a strong desire to consider themselves as iron-willed, capable of eating sugary snacks if they can indulge in a sweet, low-calorie treat instead. In fact, many people can utilize NCAS-sweetened beverages in place of a sugar-sweetened soda or other high-calorie beverage.2 [NCAS work best in replacing the sugars in beverages, as they are not suitable for high-heat cooking, and the “empty” calories are present in beverages. “Sugar-free” foods often have similar calories due to the use of non-sugar thickeners to provide the “mouth-feel” expected from sugary foods.]


Effect on Metabolism

This would mean that NCAS are a valuable tool to losing weight, right? What do you think? Newer research (appearing after most NCAS have gone off-patent) suggests that NCAS might actually be sabotaging your metabolism. Our body is host to many bacterial colonies, so many that the number of bacteria cells actually outnumbers the “human” cells. The gut is a major locale, but as these bacteria come from nature, they work. In healthy, non-obese people, the bacteria help maintain the metabolism and health of the person, including ways that function like another endocrine organ. The gut “microbiome” has been shown to be altered by the diet, and the changes alter the human metabolism.5 But NCAS are not “food,” just sweeteners, so they should not affect the gut microbiome, right? Have you learned yet?

NCAS are not sugar, and their effects as chemicals have been sparingly researched (perhaps intentionally). However, now that research published in the eminent journal Nature has surfaced, it may be time to look at those little packets as more than pretty pink, blue and yellow sachets of sweetness.6

A series of experiments revealed some exciting (for scientists) findings. First, in mice given one of three NCAS for a week, compared to mice given water, there was a distinct and rapid onset of insulin resistance. This means they could not shuttle glucose (blood sugar) into their muscles and other tissues as well. The researchers suspected this was due to a change in the gut microbiome, so they treated the mice with antibiotics to kill all the gut bacteria, and the negative change was gone. Genetic analysis of the gut microbiome showed that the NCAS-fed mice developed an “unhealthy” population. Further, when the scientists transplanted feces (poop) from the NCAS-fed mice to a separate group of mice that were raised without a gut microbiome, the same changes occurred in the mice that received the fecal transplant – without being exposed to NCAS. This supports the idea that NCAS alter the gut microbiome in an unhealthy way, rather than affecting the organ function in the mouse.

Then, the researchers looked for evidence of the same effect in humans. Using data from an ongoing nutritional study revealed that NCAS users had a higher body mass index (BMI), waist-to-hip ratio, increased fasting glucose and HbA1c 9 (a marker of long-term glucose control, so higher is bad), as well as a gut microbiome that differed from those who do not consume NCAS. Of course, it is possible that those who are already obese are more likely to use NCAS as part of a weight-loss effort.

Sabotaging Weight-Loss Efforts?

The authors tried to repeat a mini-study on humans, similar to that performed on the mice. Human subjects who did not consume NCAS routinely were given saccharin for a week, and tested before and after for signs of negative changes in how they handled sugar (aka glucose tolerance or insulin resistance), or changes in the gut microbiome. In four of the seven subjects, changes were noted. Finally, the researchers transplanted feces from subjects who showed changes, using stool samples from the day prior to receiving saccharin and after seven days of saccharin use. The pre-saccharin stool did not cause any negative changes in the mice, whereas the mice who received stool from the same human subjects after seven days of saccharin use developed signs of glucose intolerance. The pre- and post-saccharin feces had significant differences in the bacteria present, after just seven days.

While certainly not enough evidence for a conviction, it does suggest that NCAS may not be entirely benign as a food additive. NCAS may even be sabotaging weight-loss efforts in those who depend upon diet foods and beverages to a great degree.


1. Bellisle F, Drewnowski A. Intense sweeteners, energy intake and the control of body weight. Eur J Clin Nutr 2007;61:691-700.

2. Ferreira AV, Generoso SV, et al. Do low-calorie drinks ‘cheat’ the enteral-brain axis? Curr Opin Clin Nutr Metab Care 2014;17:465-70.

3. Griffioen-Roose S, Smeets PA, et al. Effect of replacing sugar with non-caloric sweeteners in beverages on the reward value after repeated exposure. PLoS One 2013;8:e81924.

4. Kelley AE, Schiltz CA, et al. Neural systems recruited by drug- and food-related cues: studies of gene activation in corticolimbic regions. Physiol Behav 2005;86:11-4.

5. Sanz Y, Santacruz A, et al. Gut microbiota in obesity and metabolic disorders. Proc Nutr Soc 2010;69:434-41.

6. Suez J, Korem T, et al. Artificial sweeteners induce glucose intolerance by altering the gut microbiota. Nature 2014;514:181-6.

The post Weight Loss, Sugar Substitutes and Obesity appeared first on FitnessRX for Men.

Read More


By: Team FitRx
Title: Weight Loss, Sugar Substitutes and Obesity
Sourced From:
Published Date: Wed, 14 Jul 2021 14:16:42 +0000

Did you miss our previous article…

Continue Reading
Click to comment

Leave a Reply

Your email address will not be published. Required fields are marked *


Ripped Leg Blast for Carved Thighs



Powerful and thick thighs require gut-busting exercises like squats and leg presses. However, once you have acquired adequate thigh mass and strength, you should consider adding some balance and sharpness to the muscle bellies in your thighs. Although tough to accomplish, leg extensions provide a great way to carve the separations between the muscle bellies, and to accentuate the “teardrop” shape of the four quadriceps muscles of the anterior thigh.

Active Muscles in Leg Extensions

The three vasti muscles comprise most of the anterior thigh.1 The vastus medialis covers the medial (inner) part of the femur bone (thigh bone). When it is well developed, it forms a teardrop-like shape over the medial side of the knee joint. The vastus lateralis muscle attaches to the lateral (outer) part of the femur bone. The vastus intermedius connects to the femur bone between the vastus lateralis and the vastus medialis muscles. The fibers of all three vasti muscles come together at the quadriceps tendon, which crosses the patella (kneecap) to attach to the tibia bone just below the knee.1

Together, the three vasti muscles extend the leg at the knee joint, although the vastus intermedius may be more fatigue resistant than the vastus lateralis.2 The vastus medialis oblique (VMO), which is a small part of the vastus medialis muscle, attaches to the medial part of the patella. It is thought to help the patella track properly during movement of the knee. Improper tracking can increase the likelihood for knee injury.

The vastus medialis and especially the VMO part of this muscle are primarily responsible for tibial rotation (rotation of the tibia bone of the lower leg on the femur) during knee extension. This rotation or “twist” has been shown to increase the activation of the VMO portion of the vastus lateralis even more than doing knee extensions with the hip adducted (thigh rotated so that the medial portion of the knee is facing mostly upwards).3 Dorsiflexion of the foot (moving the ankles so the toes are pointing towards your head) also increases the activation of the VMO by more than 20 percent.4 Likely this is because the dorsiflexor muscles stabilize the tibia during knee flexion and resist rotation of the tibia on the femur as the knee straightens.

The fourth muscle of the quadriceps group is the rectus femoris muscle. It attaches to the anterior part of the hip bone just above the hip joint.1 The largest bulk of the muscle fibers are located on the upper three-quarters of the thigh, whereas the largest belly of the vastus medialis and vastus lateralis are more inferior (i.e., closer to the knee). The distal end of the rectus femoris muscle becomes tendinous and it creates a deep valley between the lateral and medial vastus muscles as it approaches the knee.1 It assists the other quadriceps muscles by extending the leg at the knee joint, although it is less effective when the hip is flexed than if it is straight.

Leg Extensions

The three vastus muscles of the anterior thigh are strongly activated by single-leg knee extensions. The rectus femoris is not activated as strongly, but it does undergo some overload when the anterior thigh is under contractile effort, about halfway up to the top of each repetition.

1. You should always warm up your knees with some stationary cycling prior to getting into leg extensions. Furthermore, the resistance on your first set should be fairly light to allow the joint to fully warm up before you get to the heavier stuff.

2. Adjust the knee extension machine so that the pivot point of the lifting arm is directly adjacent to the center of the side of your knee joint.

3. Position the ankle roller/leg pad over the lower part of the leg (above the ankle joint).

4. Take about three seconds to slowly extend (straighten) both leg so that the weight is lifted upward from the stack.

5. Continue upwards until the tibia and the femur bones form a straight line and the knee angle is straight. Hold this for two seconds at the top.

6. Slowly lower the weight (about four seconds down) towards the starting position. Once the knee has reached 90 degrees, start the upwards extension phase again. Continue for 12-15 repetitions for the first set. Lower the number of repetitions but increase the resistance for subsequent sets.

7. On the next sets, lift the weight upwards until the knee joint becomes almost straight, but just slightly short of a total knee lockout. Be careful that you do not “jam” the knee joint into a fully locked out position, because this could cause knee cartilage damage5, especially with heavy weights. Hold the top position for a count of three before lowering the weight.

8. Lower the weight slowly (four to five seconds) towards the starting position where your knee is flexed to 90 degrees. Just before the weight stack contacts the remaining plates at the bottom, start lifting it upward for the next repetition.

The downward movement should be slower than the upward phase because you are resisting the pull of gravity. The slow lowering of the weight stretches the muscle under a resistance and this is a great stimulus to improve muscle shape and size.6

Make sure that you do not hold your breath during the lift upwards.7 Rather take a breath at the bottom (start) of the lift, and exhale as you extend the knees/legs. Take another breath at the top and slowly exhale as the weight is lowered. Take another breath at the bottom and repeat the sequence.

This is a mechanically simply exercise, but it really can be very challenging and blood depriving8,9, especially if you try to control the weight as it is moving up and down. However, if you are willing to work through some discomfort, you will be soon enjoying your new shape and slabs of carved thighs.

GettyImages 674163248 600


1. Moore K.L. Clinically Orientated Anatomy. Third Edition. Williams & Willkins, Baltimore, 1995; pp 373-500.

2. Watanabe K, Akima H. Neuromuscular activation of vastus intermedius muscle during fatiguing exercise. J Electromyogr Kinesiol 2010;20:661-666.

3. Stoutenberg M, Pluchino AP, Ma F et al. The impact of foot position on electromyographical activity of the superficial quadriceps muscles during leg extension. J Strength Cond Res 2005;19:931-938.

4. Coburn JW, Housh TJ, Cramer JT et al. Mechanomyographic and electromyographic responses of the vastus medialis muscle during isometric and concentric muscle actions. J Strength Cond Res 2005; 19:412-420.

5. Senter C, Hame SL. Biomechanical analysis of tibial torque and knee flexion angle: implications for understanding knee injury. Sports Med 2006;36:635-641.

6. Alway SE, Winchester PK, Davis ME et al. Regionalized adaptations and muscle fiber proliferation in stretch- induced enlargement. J Appl Physiol 1989;66:771-781.

7. Garber CE, Blissmer B, Deschenes MR et al. American College of Sports Medicine position stand. Quantity and quality of exercise for developing and maintaining cardiorespiratory, musculoskeletal, and neuromotor fitness in apparently healthy adults: guidance for prescribing exercise. Med Sci Sports Exerc 2011;43:1334-1359.

8. Denis R, Bringard A, Perrey S. Vastus lateralis oxygenation dynamics during maximal fatiguing concentric and eccentric isokinetic muscle actions. J Electromyogr Kinesiol 2011;21:276-282.

9. Ueda C, Kagaya A. Muscle reoxygenation difference between superficial and deep regions of the muscles during static knee extension. Adv Exp Med Biol 2010;662:329-334.

The post Ripped Leg Blast for Carved Thighs appeared first on FitnessRX for Men.

Read More


By: Stephen E. Alway, Ph.D., FACSM
Title: Ripped Leg Blast for Carved Thighs
Sourced From:
Published Date: Mon, 25 Jul 2022 19:11:16 +0000

Did you miss our previous article…

Continue Reading





Continue Reading


PRIMAL Preworkout



Training hard and intensely is the only way to train – you can’t step into the gym in low gear or
asleep at the switch and expect results. To get the most out of every training session with no
compromises, you need a pre-workout that will power your performance and enable you to crush
it every time you train. Bottom line, you need to maximize your workouts by pushing yourself to
your limits and that’s what Animal’s PRIMAL Preworkout delivers.

A Better Pump

PRIMAL is Animal’s most comprehensive pre-workout supplement ever, and is scientifically
designed for the advanced, hard trainer. Animal worked tirelessly to find the right combination of
ingredients that could be worthy of the Animal name. First on the agenda was giving you a better
pump, which is why PRIMAL Preworkout is empowered with the breakthrough, patented
3DPump-Breakthrough ® . Not only does it increase nitric oxide for the valued “pump,” but it also
helps increase exercise capacity and endurance and helps optimize vascular endothelial function,
aka vascularity.†

Other key benefits of PRIMAL come from four scientifically formulated blends that work in tandem
to deliver the ultimate pre-workout:

• Endurance & Performance Complex so you can train longer and harder. Beta-alanine,
betaine and taurine are combined as a powerful endurance trio†. Beta-alanine is a vital ingredient
used to combat the urge to quit.

• Focus & Intensity Complex helps you keep your head in the iron game so you train hard and
maintain focus. Includes the amino acid tyrosine, which is involved in neurotransmitter production;
Huperzine A for brain health; and choline bitartrate, which supports energy metabolism and helps
the brain send messages for improved mental endurance and focus†.

This blend is completed with the patented Teacrine ® . Among its many benefits includes increases
in energy without the jittery feeling, increases in motivation to accomplish tasks, mental energy
and decreases in feeling of fatigue†.

• Quick and Sustained Energy Complex is the energy core of PRIMAL Preworkout . It is
powered by a combination of tried-and-true caffeine, along with an herbal complex of green tea,
coffee bean extract and guarana†.

• Electrolyte Complex to support muscle hydration and help get you through those intense
training sessions – because proper hydration is key for maximal performance. PRIMAL
Preworkout tops it off with a combination of AstraGin ® to support nutrient uptake and Senactiv,
which helps the production of citrate synthase, an important enzyme that is responsible for
producing more ATP†.

How to Use PRIMAL
30 minutes prior to training, consume 2 rounded scoops (20.3g) with 8-12 oz of water or your
favorite beverage. Users that are sensitive to stimulants should start off with 1 rounded scoop
(10.1g) to assess tolerance.

PRIMAL Preworkout

• Enhances energy and endurance†
• Supports muscle hydration†
• Supports intense focus†
• Contains AstraGin ® to support nutrient uptake†
• Contains Senactiv ® which helps the production of citrate synthase, an important enzyme that is
responsible for producing more ATP†
• Absorption and nutrient enhancers
• Great tasting, easy to mix

PRIMAL is a pre-workout that will power your performance and enable you to crush it every time you train.

For additional information, visit
†These statements have not been evaluated by the U.S. Food and Drug Administration. This product is not
intended to diagnose, treat, cure or prevent any disease.

The post PRIMAL Preworkout appeared first on FitnessRX for Men.

Read More


By: Team FitRx
Title: PRIMAL Preworkout
Sourced From:
Published Date: Thu, 21 Jul 2022 16:51:41 +0000

Did you miss our previous article…

Continue Reading