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BodyPump is a fast paced workout with barbells. Light(er) weights, high reps, loud music and a drill instructor... if you know one, you'll know all of these group based "resistance training" workouts.

Sunday and time for a brief review of the latest exercise-related publications. Today, I picked two studies that took a closer look at something I would never suggest you'd consider a primary measure of the quality of your training: The energy expenditure during and after your workouts.

While exercise and the exercise-induced increase in energy-expenditure is an important pillar of diet (+ exercise) induced weight loss. The dietary component is what makes you lose weight, while the exercise component is meant to (a) maximize the retention of lean muscle tissue and (b) improve your overall fitness and health. If you're just "working out to burn energy" you're destined to fail; not least because you will never be able to tell exactly how many kcals you've "left in the gym". And beware: Especially while dieting, it's usually much less than you think ;-)

• People overestimate the energetic demands of "intense" exercise (Berthiaume. 2015) - In view of the fact that everyone knows the (inaccurate) rule of thumb that says that the amount of energy (in kcal) you expend when you're jogging is roughly your body weight times 10 (it's actually rather body weight times 7, unless you're running really fast, by the way), it's not surprising that Berthiaume et al.'s latest study shows that their subjects, 40 healthy men and women (age: 31.7±5.8 years, body mass index [BMI]: 24±2.6 kg/m²), significantly overestimated the amount of energy they expended during a (perceived) "intense" BodyPump(TM) workout.
  

  Figure 1: Young, healthy BodyPump practitioners overestimate the energetic demands of this kind of equipment based group workouts by over 36% (Berthiaume. 2015).

  Instead of the 394.1±116 kcal, the subjects thought they'd burned, the scientists measurements yielded an average energy expenditure of only 250.3±67.8 kcal during the 60 minute workout. Now, that's not really a problem if do BodyPump, because you like group workouts like these. In view of the fact that the typical clientele of programs like these tends to charge the energy they expend during workouts against the energy from extra food they'd like to eat (BIG mistake, learn why), this may be problematic.
  

  Figure 2: Just a reminder: The energy expenditure (kcal per kg of body weight per hour) due to body weight exercises calculated based on oxygen uptake during the exercises (traditional) or during the rest periods has been shown to be rather under- than overestimated (Vezina. 2014 | read more)

  Now, you may remember the results of Vezina's 2014 study (see Figure 2 and previous article). In said paper they used a much more precise method to arrive at the actual energy expenditure. In Berthiaume's study, a simple SenseWear armband was used. That's not the "traditional calc." in Figure 2 that proved to be so unreliable in Vezina's study, but it may still suffer from the same shortcomings when it comes to measuring anaerobic vs. aerobic energy expenditure. It would thus be prudent to be at least somewhat skeptical of the exactness of Berthiaume's results.
• Exercise type and post-workout supplementation influence post-exercise resting energy expenditure and respiratory exchange ratio (Wingfield. 2015) - I know, I have written about EPOC, which is actually nothing else than the total post-exercise energy expenditure in relation to the respiratory exchange ratio, repeatedly. There is a reason, though, that the latest study from the University of North Carolina still made it into the waredownloadsoft news: It compared six exercise sessions, consisting of three exercise modalities and two acute nutritional interventions - that's extraordinary, for sure.
  • AEE - aerobic endurance exercise - 30-min on the treadmill at 45% to 55% of the heart rate reserve), high-intensity interval running 
  • HIIT - ten rounds of a 60-s treadmill run at 85% to 95% HRR with a 60-s passive rest period), and 
  • HIRT - high-intensity resistance training consisting of leg presses and bench presses, lunges, shoulder presses, biceps curls, and triceps extensions using free weights for three sets of 6RM to 8RM followed by a 20- to 30-s rest for each set of a given exercise and 2.5 min between each exercise 
  • CHO and PRO (25 g of CHO (maltodextrin) or PRO (whey isolate) mixed with 6 oz of water in an opaque bottle. 
  With its s randomized, crossover, double-blind design, the study is also pretty well-powered, even though it had only twenty female, recreationally active participants (mean ± SD; age 24.6 ± 3.9 years; height 164.4 ± 6.6 cm; weight 62.7 ± 6.6 kg).
  

  Figure 3: Overview of the study design (Wingfield. 2015).

  Next to the post-exercise resting energy expenditure (REE) and respiratory rate (RER), which were analyzed via indirect calorimetry at baseline, immediately post (IP), 30 minutes (30 min) post, and 60 minutes (60 min) post exercise, the scientists obtained salivary samples, as well (both didn't change sign.). The latter were used to determine estradiol-β-17 and cortisol levels before the workouts. To exclude any influence of dietary changes, the subjects were asked to eat diets similar to those they had consumed when they wrote their 3-day food logs at the beginning of the study. Practically speaking, this meant that, on average, subjects ingested 2,078.7 ± 679.9 kcal, 253.7 ± 97.6 g CHO (approximately 48.8% CHO), 84.3 ± 29.9 g PRO (approximately 16.2% PRO), and 80.9 ± 36.7 g of fat (approximately 35.0% fat) per day.
  

  Figure 4: Only the HIIT modality yielded sign. inter-group differences as far as the resting energy expenditure is concerned. Even those were very transient, though, and disappeared 30 min after the workout (Wingfield. 2015).

  Interestingly, a statistical significant effect for the resting energy expenditure (REE) was observed only in the HIIT, yet not in the HIRT trial (Figure 4, A). This is a result you may not have expected based on the assumption that any form of intense activity (like resistance training in this case) should have some sort of "afterburn" effect.

• What is less surprising is the relatively small, but "significant" (statistically, only!) increase in REE in response to protein vs. carbohydrate (Figure 4, B). So, protein is thermogenic even after a workout. Unfortunately, the increase in energy expenditure and the increase in fatty oxidation as signified by the reduced respiratory exchange ratio in Figure 5 B are way too small to be of any practical relevance.
  

  Figure 5: Effect of exercise modality and CHO vs. PRO supplement on the respiratory exchange ratio (RER); lower values indicate greater fat and lower carbohydrate oxidation (Wingfield. 2015).

  Eventually, the same can be said of the decrease in RER (=increase in fatty oxidation) in response to the HIIT and the increase in RER (=decrease in fatty acid oxidation) in response to the HIRT regimen. Both are statistically significant and look large enough to be relevant. When all is said and done, it does yet not really matter if you burn fat directly or glucose first. Whether you lose or gain body fat is after all a matter of the total energy balance over days and weeks, and not the fatty acid oxidation during and 60 minutes after your workouts.

Specifically for teenagers it may be important to work out in both aerobic and anaerobic workouts. So, this would be another reason to favor the combined over the other regimen.

You will probably have overheard the "knowledgeable" trainers at the gym tell their credulous clients, who just told them they "want to lose that belly fat", that the best thing they could do was to "stop spending that much time with weight training" and to do some more (steady state) cardio. Well, in general, there's nothing wrong about steady state cardio - in fact, many studies show that it is superior to resistance training when it comes to "merely" shedding body weight (in the obese). If "weight loss" is still everything you're aspiring, though, you are either new to the waredownloadsoft or another of the "headline skimmers" who happen to ask questions that are answered not just in the article, but actually in one of the red boxes... ah, I am digressing.

So, what I actually wanted to tell you is that a recent study from the Universities of Ottawa and Calgary (Alberta. 2015), clearly contradicts the average commercial gym chain trainer's recommendation and shows that belly fat loss is better achieved with diet + resistance training.
The subjects of the study were youngsters, 304 (! the high number of participants is a huge plus of the study) 14-18 year-old overweight and obese teenagers (mean body fat almost 50%!), to be specific, who were randomized to four different treatments for 22 weeks:

Table 1: Training progression in the Aerobic and Resistance group (Alberga. 2015)

• aerobic training (Aerobic), 
• resistance training (Resistance),
• combined aerobic + resistance training (Combined) or 
• non-exercising control group (Control)

Adolescents,... ok, but unless they're too sarcopenic (=suffer from pronounced age-induced muscle loss) to hit the weights, your overweight clients or you, yourself, should be able to follow the same training programs the adolescents did and see similar results if you fully adhere to the following training prescriptions:

• Resistance: The duration of each session progressed to a maximum of about 45 min. Exercises were primarily performed on weight machines, and when required with dumbbells (lateral raise, shrugs, bicep curls, front raise, preacher curl, dumbbell pullover) or by using one's own body weight as resistance (lunges, sit-ups and abdominal crunches).
  

  Table 2: Overview of the individual workouts in the Resistance group (Alberga. 2015).

  Participants alternated among exercises from groups A1, A2, B1 and B2 shown in Table 2. Participants were asked to rest for ~ 2 min between sets and were instructed on proper breathing techniques.
• Aerobic: Participants randomized to the aerobic training group underwent a 22-week program (Table 1, left) wherein the exercise intensity and duration increased progressively to a maximum of 45 min per session. Exercise was performed on a cycle ergometer, elliptical or treadmill and participants were free to vary the machine(s) used. Exercise intensity was standardized using heart rate monitors (Polar Electro Oy, Kempele, Finland).
• Combined: This group performed the full exercise programs done by both the aerobic and resistance training groups (Table 1, left + right) during each session for a total of 4 times per week for a maximum of 90 min per session.

Figure 1: Changes in subcutaneous (SAT) and visceral (VAT) body fat at different regions; L4L5 represents area between 4th and 5th Lumbar vertebrae; * indicates sign. difference to control; # sign. difference to aerobic (Alberga. 2015).

References:

• Alberga, A. S., et al. "Effects of aerobic and resistance training on abdominal fat, apolipoproteins and high-sensitivity C-reactive protein in adolescents with obesity: the HEARTY randomized clinical trial." International journal of obesity (2005) (2015).
• Dansinger, Michael L., et al. "Comparison of the Atkins, Ornish, Weight Watchers, and Zone diets for weight loss and heart disease risk reduction: a randomized trial." Jama 293.1 (2005): 43-53.
• Thompson, A., and J. Danesh. "Associations between apolipoprotein B, apolipoprotein AI, the apolipoprotein B/AI ratio and coronary heart disease: a literature‐based meta‐analysis of prospective studies." Journal of internal medicine 259.5 (2006): 481-492.
• Walldius, G., and I. Jungner. "The apoB/apoA‐I ratio: a strong, new risk factor for cardiovascular disease and a target for lipid‐lowering therapy–a review of the evidence." Journal of internal medicine 259.5 (2006): 493-519.

I can almost guarantee that the results of this study are not sex-specific. Ladies, pick up the weights fater you hit the treadmill, stairmaster, elliptical or other torture instrument you like to use!

It has been a while since the last study on exercise order (cardio or weights first) has been published. Now, scientists from the University of Kurdistan have conducted another study to investigate the effects of intrasession sequencing of concurrent resistance and endurance training on the serum leptin, testosterone, cortisol responses and body composition in obese men.

And don't worry, we are not talking about useless acute-phase data that shows no correlation with either strength or muscle gains, or fat loss (West. 2012). Sheikholeslami-Vatani and colleagues conducted an eight-week study on thirty obese young male students without continuous exercise history (age: 23.2±1.4 year, BMI: 31.8±1.6 kg/m²).
The subjects were randomly divided into three groups: concurrent resistance-endurance (CRE, n = 10) group, concurrent endurance-resistance (CER, n = 10) group and control (C, n = 10) group (no training program). The concurrent training groups (CER and CRE) trained three times a week on alternate days for 8 weeks. The training itself consisted of which consisted of ...

"running with 70—75% of maximal heart rate (HRmax) for 10 minutes which gradually increased to 80% HRmax for 21.5 minutes [plus] resistance training consisted of 3 sets of 8 repetitions at 80% of 1 repetition maximum (1RM) in 5 resistance exercises (leg extensions, lying leg curl, triceps pushdown, bench press and lateral pull down)" (Sheikholeslami-Vatani. 2015). 

In-between the endurance and resistance (or vice versa) training parts of the workouts, the subjects rested for 5 minutes. Blood sampling and skin-fold measurements to asses the body composition was conducted 48 hours before the start of the course and again 48 hours after the last training session (learn why waiting longer for the body comp test may have been better, but no study does that).

Figure 1: Relative changes in hormone levels (left) and absolute and relative changes in body fat fat free mass and body fat % (right) after 8 weeks of doing nothing (C) or doing cardio (CER) or weights (CRE) first (Sheikholeslami-Vatani. 2015).

I've plotted the most important results in Figure 1a & b. So, let's take a look: The first thing that everyone should see is that both workout regimen had relevant health and physique effects:

• Similar gains w/ weights vs. cardio first in trained men | more.

  normalization of leptin levels (health)
• slight increases in testosterone (health)
• increases in cortisol (which are benign | learn why)
• significant reductions in body fat (health + physique)
• increases in fat free mass (health and physique)

References:

• Sheikholeslami-Vatani, D., et al. "The effect of concurrent training order on hormonal responses and body composition in obese men." Science & Sports (2015).
• West, Daniel WD, and Stuart M. Phillips. "Associations of exercise-induced hormone profiles and gains in strength and hypertrophy in a large cohort after weight training." European journal of applied physiology 112.7 (2012): 2693-2702.

Nucleotides are building blocks of our DNA and RNA and - as preliminary evi- dence suggests - ergogenic supplements for athletes on intense workout routines. In that, "intense" is the key word, 'cause normally our bodies can produce enough nucleotides on their own.

Nucleotides? Yeah, this are the small subunits, of nucleic acids like DNA and RNA. They are essential to nearly all biological processes including DNA and RNA synthesis, coenzyme synthesis, energy metabolism, cellular signaling and protein homeostasis and can be produced by our bodies "on demand" via de novo synthesis. Just like some of the non-essential amino acids which may become essential under certain circumstances, though, our bodies' own nucleotide production facility are often incapable of meeting the needs of rapidly proliferating tissues.

As Sterczala et al. (2015) point out in the introduction to their latest paper in the Journal of Strength and Conditioning Research, a salvage pathway is therefore required to synthesize nucleotides from exogenous sources (Gil. 2002).
As such, dietary nucleotides are necessary to maintain immune function, tissue growth and cellular repair. Sounds familiar? Yeah, all of those functions are affected by exercise, which can (at least temporarily) significantly increase one's nucleotide demands to levels that cannot be supplied by endogenous (=the body's own) synthesis, alone. A recent study which shows that the blunted hypertrophic response in aged skeletal muscle is associated with decreased ribosome biogenesis even suggest that this may be one of the reasons old muscle won't grow (Kirby. 2015). Consequently, there has been a growing interest in the potentiaL implications of exogenous nucleotide supplementation on exercise-induced immune
responses.

"Aside from increases in salivary immunoglobulins, McNaughton et al. (2006 & 2007) have observed a decreased cortisol response to exercise, which would partially explain the reduced immunosuppression. Animal models have observed similarly attenuated cortisol responses to stressful stimuli (Palermo. 2013, Tahmasebi-Kohyani. 2012). Given the roles of cortisol in gluconeogenesis and glycogenolysis, a reduced cortisol response may indicate a reduction in the metabolic stress of the exercise bout as a result of nucleotide supplementation. In the days following stressful exercise, [chronically (!) | see red box to learn why this is important] elevated cortisol levels could impair recovery, as cortisol can increase protein degradation and inhibit protein synthesis (Hickson. 1993; Kraemer. 2005)" (Sterczala. 2015). 

So, while we don't want to block the cortisol response to exercise altogether (here's why), Sterczala et al. are right: Attenuating or controlling it may quite beneficial. Especially if this attenuation occurs in the days after the exercise-stressor, when you want your cortisol levels to return to normal. Unfortunately, Ostojic et al. (2012 & 2013) and McNaughton et al. (2006 & 2007) who have already demonstrated the beneficial effects of nucleotide supplementation following acute exercise, did not control for the immune and cortisol response during the recovery period after the exercise stimulus. In addition, their studies involved cycling and running exercises which are, as Sterczala et al. rightly point out, "quite different in terms of muscle recruitment and metabolic demands when compared to heavy resistance exercise" (Sterczala. 2015). Therefore, the effects of nucleotide supplementation on the response patterns to resistance exercise are currently unknown and thus the perfect research object for a new study - Sterczala et al.'s new study.
Said study used a double blinded, cross-over, within subject design, with ten young men and ten women participating in the acute heavy resistance exercise protocol (AHREP) following a loading period with either a nucleotide supplement or placebo supplementation phase.

Do you remember that protease supple- mentation (e.g. 1,000mg Bromelain) has recently been shown to have ergogenic effects in athletes, too?

"The nuBound® (Nu Science Laboratories, Inc., Boston, MA [the sponsor of the study]) supplement contains dietary nucleotides, which are extracted from yeast (saccharomyces cerevisiae). During the supplement treatment cycle, subjects took two capsules of nuBound® daily, one upon waking, and one following exercise. The two capsules (1000mg) contained 278mg of dietary nucleotides, 375mg amino acids (l-glutamine, l-methionine, l-lysine), riboflavin (4.5mg), folate (400mcg), biotin (188mg) and pantothenic acid (12mcg). Other ingredients included fructo-oligosaccharides (chicory root), inositol and sodium citrate.

During the placebo cycle, subjects followed a dosing schedule identical to the supplement cycle. The placebo capsules were identical in size, shape and color to the nucleotide supplement but contained only lactose and magnesium stearate. During the first treatment cycle, subjects recorded their daily dietary intake on a diet log. The log was then used to help subjects replicate their diet during the second treatment cycle. Subjects also replicated their activity protocol during the study for each cycle" (Sterczala. 2015)."

Each cycle (placebo - PL; nucleiotides - NT) began with a two week loading phase in which subjects took the supplement while maintaining their normal exercise routines. At the beginning of the third week, an acute heavy resistance exercise protocol (AHREP) was completed. To assess the effects on recovery, subjects reported to the laboratory 24, 48 and 72 hrs following the AHREP for additional blood draws and performance testing. Before and after the the acute heavy resistance exercise protocol (AHREP), and at 24, 48, and 72 hrs thereafter, blood samples were analyzed for cortisol, myeloperoxidase, and absolute neutrophil, lymphocyte and monocyte counts. Creatine kinase was analyzed pre-AHREP and at 24, 48, and 72 hrs post-AHREP. Performance measures, including peak back squat isometric force and peak countermovement jump power were also analyzed.

Figure 1: Effects of nucleotide (NT) and placebo supplement (PL) preload for two weeks on cortisol (~stress) and creatine kinase (~muscle damage) response to exercise (Sterczala. 2015).

As you can see in Figure 1 the nucleotide supplementation resulted in significant (P ≤ 0.05) decreases in observed cortisol and MPO acutely following the AHREP, as well as significantly lower CK values at 24 hrs post. The AHREP significantly affected leukocyte counts, however, no treatment effects were observed (which is in contrast to previous studies, but in view of the disconnect between this markers and practically relevant immune outcomes, like the susceptibility to infection, irrelevant).

Figure 2: While the improved cortisol and CK are nice to see, only the accelerated force recovery in the isometric back-squat test may actually be practically relevant for athletes (Sterczala. 2015).

What is significantly more important than any of these markers of muscle stress, muscle damage or immune function is the fact that the the nucleotide supplement increased the peak force in the back squat isometric force test (albeit not the power during counter-movement jumps) immediately post AHREP and at 24 hrs and 48 hrs (see Figure 2). After all, changes like these, and not improvements in markers of whatever are what really matters for athletes.
References:

• Gil, A. "Modulation of the immune response mediated by dietary nucleotides." European Journal of Clinical Nutrition 56 (2002): S1-4.
• Hickson, et al. "Exercise and inhibition of glucocorticoid-induced muscle atrophy." Exercise and sport sciences reviews 21.1 (1993): 135-168.
• Kraemer, William J., and Nicholas A. Ratamess. "Hormonal responses and adaptations to resistance exercise and training." Sports Medicine 35.4 (2005): 339-361.
• Kirby, et al. "Blunted hypertrophic response in aged skeletal muscle is associated with decreased ribosome biogenesis." Journal of Applied Physiology 119.4 (2015).
• Mc Naughton, L., D. J. Bentley, and P. Koeppel. "The effects of a nucleotide supplement on salivary IgA and cortisol after moderate endurance exercise." Journal of sports medicine and physical fitness 46.1 (2006): 84.
• Mc Naughton, Lars, David Bentley, and Peter Koeppel. "The effects of a nucleotide supplement on the immune and metabolic response to short term, high intensity exercise performance in trained male subjects." Journal of sports medicine and physical fitness 47.1 (2007): 112.
• Ostojic, Sergej M., and Milos Obrenovic. "Sublingual nucleotides and immune response to exercise." J. Int. Soc. Sports Nutr 9 (2012): 31.
• Ostojic, Sergej M., Kemal Idrizovic, and Marko D. Stojanovic. "Sublingual Nucleotides Prolong Run Time to Exhaustion in Young Physically Active Men." Nutrients 5.11 (2013): 4776-4785.
• Palermo, Francesco Alessandro, et al. "Effects of dietary nucleotides on acute stress response and cannabinoid receptor 1 mRNAs in sole, Solea solea." Comparative Biochemistry and Physiology Part A: Molecular & Integrative Physiology 164.3 (2013): 477-482.
• Sterczala, et al. " The Physiological Effects of Nucleotide Supplementation on Resistance Exercise Stress in Men and Women." Journal of Strength and Conditioning Research (2015): Publish Ahead of Print.
• West, Daniel WD, and Stuart M. Phillips. "Associations of exercise-induced hormone profiles and gains in strength and hypertrophy in a large cohort after weight training." European journal of applied physiology 112.7 (2012): 2693-2702.

This is what science looks like... Well, at least in the Hiscock study, where the subjects, 10 young men with at leas 12 months of training experience did regular and hammer dumbbell curls on the preacher bench - (photo | Hiscock. 2015).

In today's waredownloadsoft feature article, I am going to address not one, but two potentially highly relevant articles from the Journal of Strength and Conditioning Research (Looney. 2015) and the European Journal of Sport Science (Hiscock. 2015). What makes these papers interesting is the fact that both investigated the effect of commonly prescribed remedies to "bust a plateau" by providing novel growth triggers: (a) Training to failure and (b) modifying rep schemes and whether you fail or don't fail on every set.

If you believe in what you can read in many articles on strength training, both, training to failure and decreasing rest times / drop sets should significantly increase the muscle activity and thus - this is the most important thing - the number of motor units that are recruited during the exercises.
But is this actually true? I mean, is there a link between EMG activity, the number of motor units that are firing and the way you train? I guess, it would be wise to take a brief look at the pertinent research before we get to design and results of the individual studies. So, what do we have? As Looney et al. point out, motor unit activity can be measured through electromyography (EMG) which is commonly considered to reflect the neural drive to the muscle. Since the electrical impulse should be proportional to the number of motor units that are firing and in view of the fact that the latter determines the acute force output, it should be obvious that increasing force demands result in higher EMG amplitude due to the greater recruitment of motor units and faster firing rates necessary to increase the contractile force.

Figure 1: Previous studies show that the motor unit recruited (or at least it's indicator, the mean EMG values) increases over the duration of sustained or repeated muscle actions at a constant force level (Masuda. 1999 - l; Mottram. 2005 - r)

Unfortunately, more does not necessarily help more. If you take a closer look at the existing research you have to realize you cannot stretch this proven increase of the EMG amplitude (Carpentier. 2001; Fuglevand. 1993; Lind. 1979; Masuda. 1999; Mottram. 2005; Petrofsky. 1982) infinitely. Over prolonged exercise / contraction times, the initially increasing firing rates will eventually decrease. That this is the case is interpreted by many scientists as evidence of the the fact that the initial rise in EMG amplitude is just a compensatory mechanism for sustaining contractile force as fatigue accumulates (when the individual fibers fatigue, more are recruited to sustain the same force). This hypothesis appears to be confirmed by numerous investigations that have demonstrated that EMG amplitude increases during dynamic exercise as the extent of the effort, or number of repetitions performed, increases (Hasani. 2006; Spreuwenberg. 2006; etc.).
This is where the "train to failure to maximize motor unit recruitment"-theory comes from. After all, this observation indicates that usually inactive motor units are going to fire only during prolonged training at high intensities (best to failure). As usual, though, there are problems with this theory:

"While the increase in EMG amplitude observed during repeated muscle actions has been explained by increased central drive necessary to sustain force as fatigue accumulates, it is inconclusive whether fatigue derived from earlier performed exercise induces greater EMG amplitude during subsequent exercise. Previous studies have shown EMG amplitude diminishes after strenuous resistance exercise protocols. In contrast, Smilios et al. demonstrated progressive increases in EMG amplitude over a series of 20-repetition sets with gradually decreasing resistance interspaced with 2-minute rest periods. Further uncertainly exists pertaining to consecutive maximal effort sets with progressively lighter resistance performed without allotted rest periods. This frequently incorporated training technique, commonly known as a “drop set”, has remained relatively uninvestigated" (Looney. 2015).

Needless to say that we all expect that lighter weights can stimulate greater motor unit recruitment, if you use them in dropsets, but as Looney et al. say, the science that would conclusively confirm that is simply not there (yet). The goals of Looney's study were thus as follows:

• Firstly, confirm / refute the assumption that EMG amplitude would be significantly greater in light resistance exercise (50% 1RM) performed in rested conditions to a maximal number of repetitions than to a submaximal number of repetitions. 
• Secondly, assess whether the EMG amplitude would be significantly lower in maximal repetition sets performed in rested conditions with 50% 1RM resistance than with heavy resistance (90% 1RM). 
• Thirdly, test whether the EMG amplitude would be greater in maximal repetition 50% 1RM resistance sets performed in pre-fatigued conditions (no prior rest period) than in rested conditions. 

As the authors rightly point out, the "findings of this investigation would provide critical information on understanding the changes in neuromuscular physiology during dynamic exercise related to variable levels of target repetitions, resistance, and fatigue" (Looney. 2015) and may thus be of great value to scientists (initially, because the would have to still check the practical consequences of any increases in motor recruitment) and coaches + athletes (later). What the Hiscock study in which the researchers evaluated the rate of perceived exertion (RPE) and its correlation with muscle activation and lactate levels can add to the table is information on the effect of another parameter: Different rest times.
In order to avoid any confusion, though, let's initially look at the Looney study in isolation. In said study ten resistance trained men (age, 23±3 yr; height, 187±7 cm; body mass, 91.5±6.9 kg; squat 1RM, 141±28 kg) had EMG electrodes attached to their vastus lateralis and vastus medialis muscles on two occasions:

• A drop set day, on which he subjects performed three consecutive maximal repetition sets at 90%, 70%, and 50% 1RM to failure with no rest periods in between. 
• A single set day, on which the subjects performed a maximal repetition set at 50% 1RM to failure (no "dropping" involved). 

The analysis of the EMG data yielded overall unambiguous results: The maximal repetition sets to failure at 50% and 70% 1RM resulted in higher peak EMG amplitude than during submaximal repetition sets with the same resistance. In view of the fact that the peak EMG amplitude was significantly (P ≤ 0.05) greater in the maximal 90% 1RM set than on any of the other sets the subjects performed, the classic drop set with 90%, 70% and 50% 1RM should thus still have an edge over any regular "low intensity + high rep to failure" single set training. The question remains, however, whether it will also have the edge over conventional training?

Figure 2: Very general summary of the research interests and designs of the two studies discussed in today's waredownloadsoft article by Looney et al. (2015) and Hiscock et al. (2015)

We will get back to that question in the bottom line. In the mean time, let's briefly take a look at another, quite surprising result, one that will also lead us to the results of the previously mentioned study by Hiscock et al. (2015): The lack of association between the ratings of perceived exertion (CR-10). In contrast to what most of you certainly expected, the fatigue levels did not differ over the intensity range of loads and did not reflect the degree motor unit recruitment in any way (see Figure 3). You as an individual without the necessary technical equipment are thus probably unable to tell hor many motor units you've actually recruitment in a workout; and - even more importantly - the mere fact that you have to crawl instead of walk out of the gym is not a sign of a productive workout.

Figure 4: Mean number of repetitions (left, top), rate of perceived exertion (RPE | left, bottom), and peak EMG amplitude as a measure of motor recruitment (Looney. 2015).

You don't want to believe that? Well, bad luck for you: This result appears to be confirmed by Hiscock's study, in which 10 recreationally trained (>12 months of previous resistance training) did DB Curls and DB Hammer Curls on the preacher bench for three sets with their preferred arm at a constant load of 70% of their individual 1-RM over 4 trials:

1. 3 sets × 8 repetitions × 120 s recovery between sets; 
2. 3 sets × 8 repetitions × 240 s recovery; 
3. 3 sets × maximum number of repetitions (MNR) × 120 s recovery; 
4. 3 sets × MNR × 240 s recovery.

After each of the exercises the participants rated their overall and active arm muscle rate of perceived exertion (RPE-O and RPE-AM) and the data was correlated with the biceps brachii and brachioradialis muscle EMG activity during each set for each trial.

Figure 5: Despite sign. higher volumes (see boxes) and a 100% increase in rate of perceived local muscular exertion there was no significant increase in muscle activity with lifting 70% of the 1RM for 8 vs. to failure (Hiscock. 2015).

Just like in the Looney study, the measured rates of perceived exertion in the Hiscock study had did not correlate with with either the muscle activation or the lactate accumulation in the biceps. Rather than that, it appears as if the subjects' bicepses didn't even care about rep schemes and failure. While the RPE increased significantly, when the subjects trained to failure, the mean and peak EMG activity levels in Figure 5 are more or less identical for all rep x intensity (+/- failure) schemes.
References:

• Carpentier, Alain, Jacques Duchateau, and Karl Hainaut. "Motor unit behaviour and contractile changes during fatigue in the human first dorsal interosseus." The Journal of physiology 534.3 (2001): 903-912.
• Fuglevand, A. J., et al. "Impairment of neuromuscular propagation during human fatiguing contractions at submaximal forces." The Journal of physiology 460.1 (1993): 549-572.
• Gibson, A. St Clair, E. J. Schabort, and T. D. Noakes. "Reduced neuromuscular activity and force generation during prolonged cycling." American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 281.1 (2001): R187-R196.
• Hassani, A., et al. "Agonist and antagonist muscle activation during maximal and submaximal isokinetic fatigue tests of the knee extensors." Journal of Electromyography and Kinesiology 16.6 (2006): 661-668.
• Hiscock, Daniel J., et al. "Muscle activation, blood lactate, and perceived exertion responses to changing resistance training programming variables." European Journal of Sport Science ahead-of-print (2015): 1-9.
• Lind, Alexander R., and Jerrold S. Petrofsky. "Amplitude of the surface electromyogram during fatiguing isometric contractions." Muscle & nerve 2.4 (1979): 257-264.
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