EMG Study Can Tell Us Something About Using Dumbbells, Barbells and Machines During Chest & Triceps Workouts

The dumbbell bench press is a pec stretcher. Doesn't it already look like maximal pectoralis major activity?

No, a high EMG activity will not necessarily translate into improved long-term muscle or strength gains, but it can tell you a lot about the biomechanics of different exercises and/or, as in the latest study by de Araújo Farias et al. (2016), exercise equipment and order.

The true purpose of this study by scientists from Brazil and the US was to investigate muscle activation, total repetitions, and training volume for three bench press exercise modes, the smith machine (SMBP), barbell (BBP), and dumbbell (DBP) - all followed by a triceps extension (TE).

Want to try something very different? Try BFR and Hypoxia Training

BFR, Cortisol & GH Responses

BFR - Where are we now?

Hypoxia + HIIT = Win?

BFR for Injured Athletes

Strength ⇧ | Size ⇩ w/ BFR

Training & Living in Hypoxia

With nineteen trained men as subjects, the scientists had each study participant perform three testing protocols with 4 sets of bench presses (10RM) with dumbbells, barbells or smith machine being the primary exercises that were then followed up with triceps extensions and two minutes of rest.

Figure 1: EMG activity in pectoralis (left) and the anterior deltoids (right | de Araújo Farias. 2016).

Surface electromyographic (SEMG) activity was assessed for the pectoralis major (PM), anterior deltoid (AD), biceps brachii (BB), and triceps brachii (TB).

Figure 2: Bench press repetition performance and volume for each mode (de Araújo Farias. 2016).

The results of the scientists' EMG and total volume analyses indicat that (a) dumbbells elicit a significantly greater pectoralis major activity than barbells, that (b) the anterior deltoid (shoulder) activity peaks on the smith machine, and that (c) the triceps does the least while the biceps the most work when the bench press is done with dumbbells instead of smith machine or barbell.

Chest	Biceps	Back	Core	Legs	Triceps	Shoulders
Navigate the SuppVersity EMG Series - Click on the desired body part to see the optimal exercises.

Figure 3: Mean and standard deviation values for IEMG (a) bench press (pectoralis major activation) and (b) bench press (triceps brachii activation) with and without pre-exhaustion in Suares. 2016).

Why exactly, the triceps activity during the triceps extensions was still reduced after the dumbbell bench press is not clear, but one may argue that the higher EMG activity after barbell bench presses may be the consequence of pre-exhaustion, which has been shown to augment muscle activity in previous studies, already (Brennecke. 2009; Soares. 2016 - see Figure 2); this, obviously, implies that the muscle activity in the barbell trial was increased, which is different from the initially questioned assumption that using dumbbells despite (or rather due to) their low strain on the triceps yielded inferior results.

As previously pointed out, though, there is no way of using these results for reliable prediction about the long-term adaptational response to training with dumbbell, barbell and smith machine. If we go by the prognostic power of training volume, it should be the dumbbell with a total volume of 31.2 ± 3.2 reps (versus the BBP 27.8 ± 4.8) that builds the most muscle. In that, I will leave it up to you to decide whether it's a coincidence that the dumbbell bench press also produced the greatest EMG activity ... ;-)

What I can and still want to tell you, though is that using dumbbells had the added benefit of showing the least interference with the subsequent triceps extensions (total volume: BBP = 1204.4 ± 249.4 kg; DBP = 1216.8 ± 287.5kg SMBP = 1097.5 ± 193 kg) - an observation that appears logical, and still raises the question: what's more conducive for your gains? The pre-exhaustion of the triceps you get from barbell bench presses and the resulting increase in EMG activity, or the rest your triceps will get during dumbbell bench presses and the subsequently increased training volume during triceps extensions. Well, I can't tell, but based on previous studies, it would appear as if the increased activity and decreased volume would balance each other out and explain why previous research found conflicting results (Prestes. 2015).

The jury on "pre-exhaustion" is still out there. But there is evidence of its usefulness I've discussed in previous articles on suppversity.com | example

So what do I do? You remember the benefits of daily changing loads I discussed in June 2016? Well, what if you kept your body guessing on the type of equipment you use, as well? I would not necessarily recommend switching back and forth between barbells, dumbbells, and the smith machine within a single workout and/or from one workout to the next.

What may make sense, on the other hand, is using dumbbells for two, barbells for two weeks, each, and the (boring ;-) smith machine for another week in a 5-week cycle and thus making sure that you grasp the individual benefits of each of them and the added benefit of motivation and keeping the muscle guessing.

On a side note: The study confirms what many of you probably "felt" anyways. The "best" as in "most pectoralis specific way" of bench pressing is clearly the dumbbell, which - much in contrast to the barbell and smith machine - do not allow the pecs to rest while triceps and front delts take over and lift a sign. percentage of the weight | Comment on Facebook!

References:

• Brennecke, Allan, et al. "Neuromuscular activity during bench press exercise performed with and without the pre exhaustion method." The Journal of Strength & Conditioning Research 23.7 (2009): 1933-1940.
• de Araújo Farias, D., et al. "Maximal strength performance and muscle activation for the bench press and triceps extension exercises adopting dumbbell, barbell and machine modalities over multiple sets." Journal of strength and conditioning research (2016).
• Prestes, Jonato, et al. "Discussion of “The effects of pre-exhaustion, exercise order, and rest intervals in a full-body resistance training intervention”− Pre-exhaustion exercise and neuromuscular adaptations: an inefficient method?." Applied Physiology, Nutrition, and Metabolism 40.8 (2015): 850-851.
• Soares, Enrico Gori, et al. "Comparison between Pre-Exhaustion and Traditional Exercise Order on Muscle Activation and Performance in Trained Men." Journal of sports science & medicine 15.1 (2016): 111.

Science Round-Up Seconds: Cytokine Modulating Power Cakes, Endurance & Resistance for Maximal Cardiovascular Benefit, Gluten Degrading Bacteria and Cancer Fighting Green Tea + Levitra Combo. Plus: Sirt-3 & Protein Blends

Not sure if the "Power Cakes" in the Kerasioti study looked like these, but it would sure have been appropriate, after all the poor study participants had to cycle for 3h (in total) - makes you wonder if they are WADA approved, doesn't it?

Today's installment of the SuppVersity Science Round-Up Seconds has some delicious stuff for you in stock. We will start out with an interleukin 6 & 10 modulating CRP reducing cake from Greece as an appetizer, or pre-workout, whatever you like better. When we have finished that one, the table or gym talk will center around debunking the myth that only aerobic training was good for your cardiovascular system. When even the last i**** has gotten that, it's about time to devour the delicious anti-carcinogenic and gluten destroying bacteria stew with green tea and Levitra(R), I've been cooking for ya ;-)

Before you go for the cake, however, I want to apologize that I was somewhat out of it on yesterday's show (click here to listen to the podcast). As a compensation today's Seconds have - as you can see - become pretty "nutritious" at least on a quantitative level ;-)

Looking for the perfect peri-workout meal? What about some cake?

(Kerasioti. 2013) -- It may not really sound like "high performance fuel", but in fact the protein cake a group of Greek scientists fed to their nine physically active and pretty well-conditioned male subjects (age, 28 ± 2 yr; height, 184 ± 3 cm; body fat, 11 ± 2%; body mass index, 23 ± 1 kg/m²) turned out to be much more than just performance fuel after the 2 h of continuous cycling on cycle ergometer at an intensity corresponding to 60-65% of the subjects established VO2max.

Figure 1: Interleukin 6, interleukin 10 and c-reactive protein (CRP) levels before and after the first 2h exercise bout with experimental (EXP) and placebo (PLA) cake; data expressed relative to baseline (Kerasioti. 2013).

As the data in figure 1 goes to show you, the cakes which contained a combination of 0.9g/kg carbohyrates and 0.26g/kg protein did in fact have surprisingly more beneficial effects on the rise and fall of the pro- and anti-inflammatory cytokines IL-6 and IL-10 (IL = interleukin) during the two counterbalanced trials, than the placebo, an identical cake with a different macro-nutrient ratio of 1.1g carbs and 0.1g protein per kg body weight.

Training twice a day? No problem with the power cake ;-)
 
Only four hours later the scientists shooed their subjects onto the bike again for another hour of medium intensity exercise and a 95% VO2max time-trial sprint at the end, "to determine if the cake administration affects performance" (Kerasioti. 2013). Sounds logical, right? What's confusing, though is that Kerasioti et al. don't even mention the performance effects they did or didn't observe in the second bout in the discussion of their results - so I suspect that (a) there were no differences or (b) Kerasioti et al. regard the cytokine response to the second trial as a "performance" marker and stick to that as their "effect on performance" (I don't know about you, bun in my humble opinion the latter would be an even greater flaw than leaving the non-significant information out).

Figure 2: IL-6, IL-10 and CRP response over the whole study period; expressed relative to baseline (Kerasioti. 2013)

If you add the cytokine expression in the steady state 2h trial from figure 1 to the data that was recorded after the completion of the 1h steady state + time trial cycling session four hours later and the 48h post levels of the inflammatory markers, the resulting graph exposes a very neat symmetry with an almost identical rise and fall in the expression of the short-lived cytokines and an eye-catching difference in the intermediate inflammatory response evidenced by the increase in CRP in the recovery phase of the placebo trial (just as a reminder: C-reactive protein aka CRP is the same stuff you will also see chronically elevated in diabesity and all sorts of inflammatory diseases).

A propos protein: We also talked about the benefits of protein blends with fast and slow proteins.Here is the SuppVersity article about the human study on the casein + whey combination I mentioned.

Bottom line: Compared to carbohydrates alone the combination of carbs + whey does not only offer a muscle building, but also an inflammatory edge, especially endurance athletes and anyone with a high training density will benefit from -- just like the 3g glutamine (1.5g pre, 1.5g post workout), Carl and I talked about during yesterday's installment of the SuppVersity Science Round-Up, by the way, with the only difference being that the effects of whey protein are probably mediated by it's glutathione (the master oxidant) repleting glutamylcysteine groups (Bounous. 1991), beta-lactoglobulin, lactoferrin and other anti-inflammatory compounds in whey proteins (Peng. 2009).

Cardio and weights: Your cardiovascular system loves both

(Spence. 2013) -- There is this longstanding and die hard myth that only aerobic training would be good for the heart. With the publication of a recent paper by a group of scientists from the University of Western Australia and the Liverpool John Moores University, you do now finally have something to print out, and tack it to every idiots forehead who still insists that only half-marathon running, but not resistance training could save you from cardiovascular infarction ;-)

For their 6-months experiment, the scientists recruited 23 27±5 year-old healthy male subjects who were then randomized to either either endurance (ET, n=10) or resistance training (RT, n=13) in order to evaluate the long-term effects of these training modalities on brachial, femoral and carotid artery diameter and wall thickness (IMT), as well as femoral and brachial flow-mediated (FMD) and glyceryl trinitrate (GTN) mediated dilation. Ha? Well, let's say they wanted to know how the different exercise protocols, the scientists desribe as follows,

For those of you who want to add something to their regimen that boosts the longevity sirtuin, sirt-3 Carl and I have talked about during yesterday's show, here is the HMB + Leucine study I mentioned.

"[...] the ET intervention consisted of a progressivelyoverloaded programme of walking, jogging and running, inclusive of specified training phases over the 24week period. The focus of the periodized RT programme was Olympic weightlifting with incorporated supplemental exercises (e.g. dead-lift, back squat, front squat, bench press and overhead press) to develop overall strength and technique. Relative intensities for the ET and RT interventions were monitored throughout the sessions, individualized and progressed to ensure that subjects were exercising at prescribed percentages of VO2peak and 1RM, respectively" (Spence. 2013)

would effects the structure and performance of the hearts of their subjects, who completed three 1h training sessions of the respective exercise type per week.

As even resistance training enthusiasts should have expected, the RT group did not see significant improvements in O2Peak (ET yielded +5% increase in this indicator of cardiovascular fitness). On the other hand, the endurance training had no effect on upper body strength, which increased by statistically highly significant +21% in the resistance training group. Both these improvements are yet not really newsworthy and the whole study would not have made it to the SuppVersity Science Round-Up, respectively the Seconds, if it had not been for the high-resolution ultrasound images of the heart, which revealed:

Figure 3: Changes in body composition
relative to pre values (Spence. 2013)

• Resistance training affects the brachial artery, increases brachial artery resting (+8%, P<0.05), peak FMD  and GTN-mediated (P<0.01) diameters
• Endurance training affects the femoral artery, increases resting (+3%, P<0.05), peak FMD femoral artery diameters, and improvements in the femoral FMD-to-GTN% ratio 
• Both forms of training had similar beneficial effects the carotid artery wall thickness

In summary: Despite the fact that the two training forms will have differential effects on your overall conditioning and strength, they both increase lean mass (see figure 3) and decrease the artery wall thickness of the artery which supplies your brain with oxygen (the carotid artery). And with their unique effects on the brachial artery in the upper arm (RT) and the femoral artery in the tigh (ET), they make a perfect team to protect you from cardiovascular disease and stroke.

"I'd like a Levitra(R) enhanced green tea with probiotics..." What?

The last two items from yesterday's list that did not make it into the show are actually not brand new studies. One is a comment from the Journal of Clinical Investigation and the other one is a study that has been around since 2011, already. I picked them up in the course of the week and found them news-worthy, although it is not really sure, a combination of green tea, viagra and rothia bacteria is going to prevent cancer and solve your problems with gluten or whether one or the other or a combination of all is going to kill you ;-) Anyways, here are the details:

• 

  Rothia has hitherto rather been known as a bad guy, which can, if it gets into the wrong places cause endocarditis (heart), meningitis (brain), peritonitis (an inflammation of the peritoneum, the thin tissue that lines the inner wall of the abdomen and covers most of the abdominal organs) and other infections (Photo by Nathan Reading)

  Rothia bacteria in the upper gastrointestinal tract degrade gluten (Zamakharchi. 2011) -- Back in 2011 already a group of researchers from the Boston University Henry M. Goldman School of Dental Medicine published a paper in which they describe the astonishing ability of a common gram positive bacteria called Rothia, which is also present in the oral cavity could degrade 50% of the glyiadin peptides the scientists had added to the petri dish before the they were incubated for 30min.
  
  In view of the fact that the immunogenic parts of the peptides, that cannot be cleaved by our natural digestive enzymes, it does appear like a too happy coincidence that our microbial subtenants from the oral and upper gastrointestinal tract possess the enzymatic machinery to degrade the harmful gluten peptides for us - don't you think so?
  
  One thing is for sure, the presence of a bacteria that deals with the stuff, we cannot deal with on our own in our oral cavity certainly does support what I said in the context of the "bulimia apparatus" - the digestive process with all it's downstream effects on your metabolism starts in the mouth:
  

  "During mastication (chewing) foods are mixed with whole saliva helping to accelerate the break-down by digestive enzymes during the residency time in the oral cavity. Oral microorganisms in the swallowed food bolus may or may not survive and/or continue to exert proteolytic activities during or after gastric passage. Our in vitro data with R. aeria show that its enzymes are not abolished at acidic pH values, and are optimally active under more basic pH conditions. In vivo, this could mean that during gastric passage the enzymes will neither be active nor destroyed, and that enzymatic reactivation would occur upon transfer to the duodenum." (Zamakharchi. 2011)

  Aside from the fact that they could make it into the large intestine, previous studies have already confirmed that R. mucilaginosa can even gain a foothold there (Ou. 2009), so that probiotic supplementation with Rothia mucilaginosa could in fact turn out to be a viable treatment / prevention strategy for celiac disease and other gluten related health problems.

• EGCG + PDE-5 = cancer killer (Yang. 2013) -- Cancer is like the Learnean Hydra from ancient Greek mythology (see image on the right). Whenever you cut off one of its heads it'll grow two new ones... well, i must admit the analogy isn't perfect, but it's still useful to understand why the PDE-5 inhibitor vardenafil worked wonders when it was co-administered with the green tea catechin EGCG.
  
  

  

  You really have to wonder why these ancient heroes who had the cunning to kill the Hydra did not even wear a pair of speedos, when they entered into it's watery realms ;-)

  Just like the many Greek warriors who died in their battle with the Hydra before it was finally slain by Heracles, EGCG is well capable of doing major harm to the cancer cells. Just like the snake-like beast the cancer cells have yet found a way to resist the onslaught. Obviously not by growing new heads, though, but rather by over-expressing PDE-5 in order to repress the EGCG increased cGMP activity that would otherwise initiate apoptosis, i.e. the natural self-destruction mechanism of a cell.
  
  So what could be more straight forward than using a PDE-5 inhibitor just like Iolaus, Heracles cousin, used a firebrand to scorch the neck stumps of the Hydra after each decapitation. Clever and effective, don't you think so?
  
  Well, there still is one downside: Just like the story about the Hydra is nothing but a myth, the studies Yang and Wang reference in their commentary in the latest edition of the Journal of Clinical Investigation are only in-vitro studies and whether drinking green tea and popping one of Bayer's Levitra(R) pills after the other, is going to prevent, let alone kill existing cancer, will still have to be elucidated.

That's if for today! And since I am a bit in a hurry, I will leave it up to you to check out the latest really short news on the SuppVersity Facebook wall. Contrary to the green tea + Levitra treated cancer cells, the facebook news are guaranteed to proliferate even before the official Saturday installment of On Short Notice is going to be posted in ~24h (in fact, it will first have to researched and written ;-)

References:

• Bounous G, Gold P. The biological activity of undenatured dietary whey proteins: role of glutathione. Clin Invest Med. 1991 Aug;14(4):296-309.
• Kerasioti E, Stagos D, Jamurtas A, Kiskini A, Koutedakis Y, Goutzourelas N, Pournaras S, Tsatsakis AM, Kouretas D. Anti-inflammatory effects of a special carbohydrate-whey protein cake after exhaustive cycling in humans. Food Chem Toxicol. 2013 Jan 26.  [epub ahead of print] 
• Ou G, Hedberg M, Horstedt P, Baranov V, Forsberg G, et al. Proximal small intestinal microbiota and identification of rod-shaped bacteria associated with childhood celiac disease. Am J Gastroenterol. 2009;104:3058–3067.
• Peng X, Xiong YL, Kong B. Antioxidant activity of peptide fractions from whey protein hydrolysates as measured by electron spin resonance. Food Chemistry. 2009; 113(1):196–201. 
• Spence AL, Carter HH, Naylor LH, Green D. A prospective randomised longitudinal study involving 6-months of endurance or resistance exercise on conduit artery adaptation in humans. J Physiol. 2013 Jan 28. [Epub ahead of print] 
• Yang CS, Wang H. Cancer therapy combination: green tea and a phosphodiesterase 5 inhibitor? J Clin Invest. 2013 Jan 25:1-3. [Epub ahead of print]
• Zamakhchari M, Wei G, Dewhirst F, Lee J, Schuppan D, Oppenheim FG, Helmerhorst EJ. Identification of Rothia bacteria as gluten-degrading natural colonizers of the upper gastro-intestinal tract. PLoS One. 2011;6(9):e24455.