In this case, it appears the bros were right…!

For as long as I can recall, bodybuilders have been preaching the importance of a mind-muscle connection for maximizing muscle development. In case you’re not aware, a mind-muscle connection (a variation of the concept in the field of motor learning known as an “internal focus of attention”) is the process of actively thinking about the target muscle during training and then feeling it work through the full range of motion. According to theory, this strategy maximizes stimulation of the muscles you’re trying to target in a given exercise while reducing the involvement of “secondary” movers. This combination hypothetically should result in greater growth.


Numerous studies have confirmed that a mind-muscle connection does in fact increase activation of the target muscle as measured by a technique called electromyography. However, higher activation of a muscle doesn’t necessarily mean it will hypertrophy to a greater extent over the course of a long-term training program. To my amazement, no one had endeavored to investigate whether adopting a mind-muscle connection during training actually had a beneficial effect on muscle growth in a controlled, long-term study.

So the curious science nerd that I am, I took it upon myself to find out. Here’s the scoop on our recently published paper on the topic.

What We Did
30 college-aged men agreed to participate in the study and were randomly...

In a recent blog post , I, along with my colleague Bret Contreras, published a “letter to the editor” that raised issue with various claims made in a review of exercise-induced muscle damage. In the spirit of scientific discourse, we invited the authors of the paper – Felipe Damas, Cleiton Libardi, and Carlos Ugrinowitsch – to publish a rebuttal to our letter on my site. They have obliged and what follows is their response.

We acknowledge the authors of the letter to the Editor for the opportunity to continue the debate on the interesting topic of mechanisms related to resistance training (RT)-induced skeletal muscle hypertrophy. While we agree that the role of muscle damage on muscle hypertrophy needs further scientific scrutiny, as we pointed out in our article (Damas et al. 2018a), current evidence indicates that muscle damage promoted by initial resistance exercise (RE) does not predict, explain, or potentiate skeletal muscle hypertrophy induced by weeks of RT (Damas et al. 2016; Flann et al. 2011). Moreover, if muscle damage magnitude is severe, the exercise-induced stress results in maladaptation, segmental necrosis or even muscle atrophy (Butterfield 2010; Eriksson et al. 2006; Foley et al. 1999; Lauritzen et al. 2009). That said, it remains to be elucidated if disturbances within muscle fibres, e.g., Z-band streaming, muscle repair and remodelling are required in early RT phases to prepare muscle tissue to endure further stresses; albeit delayed onset muscle soreness, muscle proteins (e.g., creatine kinase) leakage to bloodstream, or large...

Recently, Damas et al (2018) published an interesting review on the role of exercise-induced muscle damage in muscle hypertrophy. Although the paper was well-done overall, my colleague, Bret Contreras, and I felt there were several issues that needed to be highlighted. We endeavored to send a letter to the editor at the journal in which the paper was published (European Journal of Applied Physiology). Unfortunately, the journal has a strict word count for letters to the editor, and the editor asked us to cut down the length of our letter to accommodate the journal’s guidelines. We attempted to comply with this request and submitted a revision, but the editor stated the letter would have to be cut down still further to meet requirements. At that point, we declined a further revision as we did not want to water down our points simply to have the letter published.

Thus, we have decided to post the letter online so that it can be read in its entirety. We have the utmost respect for the authors of the paper and would welcome to publish their rebuttal here if they so choose. Hopefully this will further discussion and point out the nuances of drawing conclusions on a topic as complex as this.

We read with interest the paper by Damas et al (Damas et al. 2017) titled, “The development of skeletal muscle hypertrophy through resistance training: the role of muscle damage and muscle protein synthesis,” which, in part, endeavored to...

Today marks the first day of the new year and the gyms are going to be packed with people whose resolution is to get into shape. Problem is, the vast majority will have quit working out before the end of February. A few things to remember if you’re new to training or getting back after a lengthy layoff:

1. You’re not going to change your body in a week, so don’t overdo it at the beginning; you’ll just end up overly sore which will diminish your ability and desire to train. Start off slow and don’t push it the first few sessions so that your body acclimates to the stress of exercise. As you progress, gradually increase the intensity of training over time in a manner necessary to continually challenge your body to realize continued positive adaptations.

2. Have a plan. If you’re aimlessly walking around the gym deciding what to do, chances are you won’t get optimal benefits. Exercise is a science and should be approached accordingly. Set your goals, create a program consistent with your goals, and then follow the program you’ve laid out. If it’s not working the way you want over time, then assess and refine as required. One of my favorite quotes: Those who fail to plan, plan to fail.

3. Know how to perform exercises properly. Overall the form I see people use in the gym is anywhere from poor to horrendous. Not performing an exercise with good biomechanics at the very least will diminish...

Below is an excerpt from my book, Strong & Sculpted that discusses my current approach to warming up prior to resistance training. I neglected to include a chapter on the topic in my book, M.A.X. Muscle Plan so for those following this program, the same info applies.

To prepare your body for the demands of intense exercise, you should warm up prior to your lifting session. The warm-up contains two basic components: a general warm-up and a specific warm-up. Here’s what you need to know about each component for a safe, effective workout.

General Warm-Up
The general warm-up is a brief bout of low-intensity, large muscle–group, aerobic-type exercise. The objective is to elevate your core temperature and increase blood flow, which in turn enhances the speed of nerve impulses, increases nutrient delivery to working muscles and the removal of waste by-products, and facilitates oxygen release from hemoglobin and myoglobin.

A direct correlation exists between muscle temperature and exercise performance: when a muscle is warm, it can achieve a better contraction. As a rule, the higher a muscle’s temperature is (within a safe physiological range), the better its contractility. And because better contractility translates into greater force production, you’ll ultimately achieve better muscular development.

What’s more, an elevated core temperature diminishes a joint’s resistance to flow (viscosity). This is accomplished via the uptake of synovial fluid, which is secreted from the synovial membrane to lubricate the joint. The net effect is an increase in range of...

The beauty of science is that is self-correcting. When a study is published, others get to scrutinize the data and methods. When issues arise, the scientific community gets to discuss and debate the findings, and when appropriate, challenge their veracity.

Recently, I collaborated with some of the world’s top sports scientists on a letter to the editor about a study published in the Journal of Strength and Conditioning Research, that showed an extremely large anabolic effect to consuming a supplement containing HMB+ATP. We wrote an extensive letter that covered our issues with the paper in hopes of seeking truth in science. However, we had to substantially cut down our response to conform to the journal’s policy of allowed only 400 words in such letters. This watered down our points so that the true impact was markedly diminished.

Thus, I wanted to present the unedited version of our letter here so that further discussion can be had on the topic. Only through discourse can we maintain confidence in the research process and facilitate true evidence-based practice.

Extraordinary changes in body composition and performance with supplemental HMB-FA+ATP

Stuart M. Phillips, Ph.D., McMaster University
Alan Aragon, M.S., California State University, Northridge
Shawn M. Arent, Ph.D., Rutgers University
Graeme L. Close, Ph.D., Liverpool John Moores University
D. Lee Hamilton, Ph.D., University of Stirling
Eric R. Helms, M.S., M.Phil, Sports Performance Research Institute New Zealand
Jeremy P. Loenneke, Ph.D., The University of Mississippi
Layne Norton, Ph.D., Owner BioLayne LLC
Michael J. Ormsbee, Ph.D., Florida State...

Anoop Balachandran PhD & Brad Schoenfeld PhD

We are glad that more and more people are demanding and applying evidence in the exercise and nutrition field. That been said, there remains a lot of misunderstanding and misconceptions about an evidence-based Practice (EBP). In this article, we will address some of the common misconceptions and criticisms of EBP. Here we go:

Why do we need EBP? Why can’t we just use anecdotal evidence or expert opinion?

In fact, we’ve used anecdote or expert opinion as ‘evidence’ to treat people throughout the history of medicine. But this approach clearly didn’t work well as shown by hundreds of examples of medical mistakes we made in the past. For example, smoking was ‘good’ for heath until studies showed otherwise; bloodletting was the standard medical treatment for almost 2000 years by the foremost doctors of the West, and so forth. In short, EBP evolved because anecdotal evidence or expert opinion were not producing ‘results’.

You can read more about it here: Why We Need an Evidence-Based Approach in the Fitness Field.

So what is EBP/EBM?

The definition of EBM (Evidence Based Medicine) by David Sackett reads: “EBM is a systematic approach to clinical problem-solving that allows integration of the best available research evidence with clinical expertise and patient values”. This principle can be applied across many scientific disciplines, including exercise and nutrition, to optimize results.

What is the evidence?

Many people wrongly assume that the term “best available evidence” in EBM/EBP is limited to research-based evidence. In fact, evidence can...

A popular theory among fitness professionals is that taking short rest periods between sets maximizes muscular growth. The theory is primarily based on the hormone hypothesis, whereby limiting inter-set rest promotes greater elevations in post-exercise growth hormone, IFG-1 and testosterone, and thus enhances the anabolic response to resistance training. One little problem: Emerging evidence indicates that acute increases in anabolic hormones have little if any effect on muscular adaptations, as detailed in my comprehensive review of the topic

In an effort to directly test the theory, our group published a study last year titled, Longer inter-set rest periods enhance muscle strength and hypertrophy in resistance-trained men. In brief, the study not only refuted the claim of a hypertrophic benefit to short rest periods, but in fact showed that resting 3 minutes between sets actually produced superior growth compared to resting 1 minute. Importantly, the study was carried out using a moderate rep range (8-12 reps/set) with all sets performed to muscular failure. The question therefore arises whether results would be applicable when training with lighter weights. No study had ever investigated the topic.

Until now…

In collaboration with colleagues in Japan, we sought to investigate the effects of low-load resistance training with different rest intervals on muscular adaptations. The study titled, Acute and Long-term Responses to Different Rest Intervals in Low-load Resistance Training, was just published in the International Journal of Sports Medicine.

Here’s the lowdown.

What We Did
Subjects were 21 young collegiate athletes who had not...

Dating back to my early years as a personal trainer in the mid-90’s, I began to become intrigued by the concept of “loading zones” whereby different rep ranges purportedly could bring about differential effects on muscular adaptations. Prevailing wisdom at the time was that heavy loads (1-5 RM) promote maximal strength gains, moderate loads (6-12 RM) elicit maximal increases in muscle mass, and light loads (15+ RM) produce the greatest improvements in local muscular endurance. This concept, discussed extensively in exercise science texts, was termed the “strength-endurance continuum” (see the image below) although direct research on the topic was limited.

The topic of rep ranges was so intriguing to me that I ultimately made it a focus of my doctoral work. Several years ago I published the data collected in accordance with my dissertation study. In brief, the study looked at muscular adaptations in a “bodybuilding-type” routine versus a “powerlifting-type” routine in resistance-trained men when the routines were equated for volume load. Consistent with the “strength-endurance continuum” concept, the study found that the powerlifting-type routine produced the greatest strength increases. Contrary to prevailing wisdom, however, both routines produced similar increases in hypertrophy of the biceps brachii. You can read my write-up of the routine in this blog post.

Importantly, the findings of that study are specific to the respective routines being equated for volume load. While this...

The question as to how much strength training volume is needed to maximize muscular gains has been an ongoing source of debate, both in scientific circles as well as the realm of social media. Some claim that a very low volume approach is all that’s required while others subscribe to the belief that marathon training sessions are an absolute necessity.

Who’s right? Well…

Back in 2010, my colleague James Krieger carried out a meta-analysis to provide evidence-based clarity on the topic. In case you’re not aware, a meta-analysis pools data from all relevant studies on a given subject to provide greater statistical power and thus enhance the ability to draw practical inferences from the literature. In short, the analysis showed that performance of multiple sets was associated with a 40% greater hypertrophy-related effect size (a statistical measure of the meaningfulness of results) compared to single-set training.

While this paper provided good evidence in support of higher training volumes, there were some issues with the analysis. For one, James only looked at sets per muscle per workout; a potentially more important marker in determining the hypertrophic response is the weekly volume per muscle group. Moreover, only 8 studies qualified for inclusion in James’ analysis at the time, and only 3 of these studies used direct site-specific measures of muscle growth (i.e. MRI, ultrasound, etc).

Since publication of James’ meta-analysis, a number of additional studies have been published in the peer-reviewed literature. Given this info and in an...

A long-held belief in bodybuilding circles is that your body can only absorb a fairly small amount of protein in a single feeding. The exact dosage varies depending on who you listen to, but it’s generally purported to be somewhere around 20-30 grams of protein per meal.

While the claim is often taken as gospel, let’s take a close look at the research to draw evidence-based conclusions on the topic.

First and foremost, it’s important to note that from a nutritional standpoint the term “absorption” refers to the passage of nutrients from the gut into circulation – and in this context, there is virtually no limit to protein absorption. Once digested, the constituent amino acids of a given protein are transported through the intestinal cells (enterocytes) and then enter the bloodstream – pretty much all the amino acids consumed become available for use by tissues. The only potential issue with absorption is when you ingest individual free-form amino acids, as this can cause competition at the enterocytes whereby the amino acids present in the highest concentrations are absorbed at the expense of those that are less concentrated (6).

The more relevant question here is whether there’s in an upper limit to how much protein your body can use for muscle-building purposes. This question is a lot more complex and an evidence-based answer requires a good deal of extrapolation based on the limitations of current research.

Some researchers have proposed that muscle protein synthesis tops out at approximately 20-25 grams...

Wanted to keep you updated on all that is going on at the moment. So much to share!

  • In case you haven’t heard, my newest consumer book called Strong and Sculpted, was released a few weeks ago. Happy to report it’s been the top-selling new book in’s “weight training” category and has gotten stellar reviews from consumers and pros alike. It’s a scientifically-based handbook for optimizing muscle development, providing step-by-step guidelines for program design. Check it out! In addition, my upcoming textbook called, Science and Development of Muscle Hypertrophy, is scheduled to be released at the end of the month. It will be the first text to provide an evidence-based perspective on muscle growth, covering all the research and its practical implications. If you’d like to be amongst the first to receive the book, it’s now available for pre-order on at a 20% discount.

  • A recent study published in the Journal of the International Society of Sports Nutrition reported that branched chain amino acid (BCAA) supplementation helped accelerate fat loss while preserving lean mass in trained individuals performing resistance training when dieting. On the surface, this would seem to provide compelling evidence of a benefit to supplementation. However, after scrutinizing the study’s methods, my colleagues Alan Aragon, Brad Dieter, and I found some glaring issues with the statistical procedures and reporting...
  • Training frequency is one of the most hotly debated topics in the field of resistance training. While traditionally the term frequency has been associated with how many days a week you work out, a potentially more important variable is the number of times a given muscle group is trained per week.

    The internet is littered with varying opinions as to optimal training frequency for maximizing muscle hypertrophy. Some preach the typical bodybuilding “bro-split” which involves training each muscle group once a week with high volumes per session, whereas others propose training each muscle as many as 6 days a week with lower per-session volumes is the best way to get jacked. Problem is, all these opinions are largely anecdotal with limited scientific support. Seems hard to believe, but there hasn’t been a whole lot of research on the topic, and the studies that have been carried out have employed a variety of methodological designs that makes it difficult to sort out a conclusion at face value.

    In an attempt to achieve better clarity on the effects of frequency on muscle growth, I recently collaborated on a meta-analysis with colleagues James Krieger and Dan Ogborn. In case you’re not aware, a meta-analysis pools data from all studies on a given subject to provide greater statistical power and thus enhance the ability to draw practical inferences.

    Here’s the lowdown:

    What We Did
    A literature search was conducted to locate all studies that directly compared measures of hypertrophy for different weekly lifting...

    I was recently interviewed for an article by Men’s Health Magazine on how to target the lower aspect of the abdomninals. As discussed in the article, there is evidence that you can increase activation of the lower abdominal region by initiating a posterior pelvic tilt during performance of exercises such as the reverse crunch and hanging knee raise. Here is a video depicting proper performance:

    Now what isn’t clear is whether the increased activation of the lower abs translates into greater muscle development over time. There is emerging research that muscle growth is correlated to the region of greatest activation, but the evidence is far from conclusive at this point. Taking all things into account, there is a potential benefit to performing targeted lower abdominal exercise for those seeking to maximize development in this region. It probably won’t make much of a meaningful difference for the average gym-goer, but for those who aspire to develop their physique to the utmost (i.e. bodybuilders) it may well provide a tangible benefit.