Table Of ContentVOLUME 4, ISSUE 6 JUNE 2020
M A S S
MONTHLY APPLICATIONS IN
STRENGTH SPORT
ERIC HELMS | GREG NUCKOLS | MICHAEL ZOURDOS | ERIC TREXLER
The Reviewers
Eric Helms
Eric Helms is a coach, athlete, author, and educator. He is a coach for drug-free strength and
physique competitors at all levels as a part of team 3D Muscle Journey. Eric regularly publishes peer-
reviewed articles in exercise science and nutrition journals on physique and strength sport, in addition
to writing for commercial fitness publications. He’s taught undergraduate- and graduate-level nutrition
and exercise science and speaks internationally at academic and commercial conferences. He has a
B.S. in fitness and wellness, an M.S. in exercise science, a second Master’s in sports nutrition, a Ph.D.
in strength and conditioning, and is a research fellow for the Sports Performance Research Institute
New Zealand at Auckland University of Technology. Eric earned pro status as a natural bodybuilder
with the PNBA in 2011 and competes in unequipped powerlifting, weightlifting, and strongman.
Greg Nuckols
Greg Nuckols has over a decade of experience under the bar and a B.S. in exercise and sports
science. Greg earned his M.A. in exercise and sport science from the University of North Carolina
at Chapel Hill. He’s held three all-time world records in powerlifting in the 220lb and 242lb classes.
He’s trained hundreds of athletes and regular folks, both online and in-person. He’s written for many
of the major magazines and websites in the fitness industry, including Men’s Health, Men’s Fitness,
Muscle & Fitness, Bodybuilding.com, T-Nation, and Schwarzenegger.com. Furthermore, he’s had the
opportunity to work with and learn from numerous record holders, champion athletes, and collegiate
and professional strength and conditioning coaches through his previous job as Chief Content
Director for Juggernaut Training Systems and current full-time work on StrongerByScience.com.
Michael C. Zourdos
Michael (Mike) C. Zourdos, Ph.D., CSCS, has specializations in strength and conditioning and skeletal
muscle physiology. He earned his Ph.D. in exercise physiology from The Florida State University (FSU)
in 2012 under the guidance of Dr. Jeong-Su Kim. Prior to attending FSU, Mike received his B.S. in
exercise science from Marietta College and M.S. in applied health physiology from Salisbury University.
Mike served as the head powerlifting coach of FSU’s 2011 and 2012 state championship teams. He
also competes as a powerlifter in the USAPL, and among his best competition lifts is a 230kg (507lbs)
raw squat at a body weight of 76kg. Mike owns the company Training Revolution, LLC., where he has
coached more than 100 lifters, including a USAPL open division national champion.
Eric Trexler
Eric Trexler is a pro natural bodybuilder and a sports nutrition researcher. Eric has a PhD in Human
Movement Science from UNC Chapel Hill, and has published dozens of peer-reviewed research
papers on various exercise and nutrition strategies for getting bigger, stronger, and leaner. In
addition, Eric has several years of University-level teaching experience, and has been involved in
coaching since 2009. Eric is the Director of Education at Stronger By Science.
Table of Contents
6 B Y G R E G N U C K O L S
How Different Rep Ranges Affect Muscle Growth and
Strength Gains
This article discusses a study that compared the hypertrophy and strength effects of
training in different intensity zones. The biggest takeaway is that when interpreting a
study, you can’t always read between the lines.
15 B Y M I C H A E L C . Z O U R D O S
Autoregulating with Session RPE
MASS discusses autoregulation with RPE on a regular basis, but typically in terms
of the repetitions in reserve variety of RPE. Rarely do we venture into the realm
of session RPE. This article breaks down the first study to use session RPE as a
progressive overload strategy.
27 B Y E R I C H E L M S
Are the Benefits of Pre-Training Meals “All in Your Head”?
I previously reviewed an article in which skipping breakfast resulted in reduced lifting
performance. This new study from the same group reported similar results; however,
the mechanisms may be psychological or central in nature.
39 B Y E R I C T R E X L E R
Keto-Gaining Revisited
Back in Volume 2, Dr. Helms reviewed a study indicating that “keto-gaining” (building
muscle on a ketogenic diet) might be difficult due to reductions in appetite. This
month, the same research group is back with a follow-up study. Read on to find out if
their original results held up this time around.
50 B Y G R E G N U C K O L S
An Update on Concurrent Training
Concurrent training – combining resistance training and aerobic training – won’t “kill
your gains” like many claim. However, a recent study suggests that if you bike for
your endurance work, you may be increasing your risk of hamstrings strains.
61 B Y M I C H A E L C . Z O U R D O S
New Postactivation Potentiation Data is Less Promising
The first ever study on postactivation potentiation and resistance training performance
showed that postactivation potentiation improved squat performance by six reps
on only one set. However, a new study fails to replicate these findings in the bench
press. This article provides a comprehensive look at the state of the literature on
postactivation potentiation and its utility for lifting.
72 B Y E R I C T R E X L E R
Protein Distribution Matters, To An Extent
One of the most common questions in the world of nutrition is, “How much protein
should I eat, and when?” A new study adds some nuance to the conversation, and
suggests that protein distribution matters in some contexts. Read on to find out if
you’re maximizing the impact of the protein in your diet.
87 B Y G R E G N U C K O L S
New Research on Hamstrings Training
A recent study compared the acute effects of knee flexion- and hip extension-based
hamstrings exercises at long and short muscle lengths. Though acute findings should
be interpreted cautiously, results suggest that exercises like seated leg curls may be
ideal for hamstrings development.
96 B Y M I C H A E L C . Z O U R D O S
VIDEO: Eccentric Duration Training
A faster concentric velocity on the squat and bench press is generally good, but we
rarely discuss the eccentric portion of the movement. When training for strength, the
goal of the eccentric is to maximize the concentric, so how fast should your eccentric
be? This video gives you some specific guidelines based on recent literature.
98 B Y E R I C H E L M S
VIDEO: Evidence-Based Practice Part I
Being “evidence based” is something that most MASS subscribers strive for as
coaches, content producers, or as a way to get the best results in the kitchen or
gym. But, what does that really mean? In this video you’ll learn what evidence-
based practice actually means, what its roots are, and what this systematic and
continuous process looks like.
Letter From the Reviewers
W
elcome to another packed issue as we reach the halfway point of Volume 4.
On the nutrition side, Eric Trexler covers two quintessential topics: protein
distribution and keto-gaining. For protein, Eric T’s review examined what
effects a high-protein breakfast versus a low-protein breakfast had on strength and lean
mass, while examining if it’s possible to build muscle on a ketogenic diet in his other
article. To round out this month’s nutrition content, Eric H. reviewed a unique study
which tested if a pre-training meal really enhances lifting performance or if this is
perhaps just a psychological benefit.
One of Greg’s articles returns MASS to the timeless topic of concurrent training and
reveals one potential flaw with the classical argument of including cycling as the
predominant mode of cardio. Greg also takes on another classic concept by reviewing
a new longitudinal study which looked at volume-equated training between programs
using either 4, 8, or 12 repetitions on hypertrophy and strength. Importantly, Greg
discusses the magnitude of volume differences between training protocols which may
actually be practically relevant. Lastly, Greg reviewed a study which examined how
hip angle affected knee extension performance and vice versa and how both hip angle
and knee extension affect hamstring activation. Ultimately, this data is potentially
useful to determine how to maximize hamstring growth.
Mike returns to postactivation potentiation this month; however, the new study on
this topic reports less-promising results than previous literature. Additionally, Mike
covers a new long-term autoregulation study, this time with session rating of perceived
exertion driving the session-to-session progressions. Importantly, Mike provides direct
practical application for these strategies in both articles.
On the video front, Eric H. brings to the table a unique video which discusses exactly
what an evidence-based approach means and how to conceptually integrate findings into
practice. Finally, Mike’s video examines the often-overlooked eccentric component of
the squat and bench press. Specifically, Mike examines the data which shows exactly
how long your eccentric duration should be to maximize concentric performance.
Lastly, it’s been a while, but we also do Q&A videos from time to time. To ask a
question for a future Q&A video, just go to the Facebook group, and in the search bar
on the left side of the page, search “Q&A” and the official thread will pop up. Then,
ask a question in the thread and we’ll get to it in the future.
Enjoy the issue, have a great month, and see you in July
5
Study Reviewed: Effects of 4, 8, and 12 Repetition Maximum Resistance Training Protocols
on Muscle Volume and Strength. Kubo et al. (2020)
How Different Rep Ranges Affect
Muscle Growth and Strength Gains
BY GREG NUCKOLS
This article discusses a study that compared the hypertrophy
and strength effects of training in different intensity zones. The
biggest takeaway is that when interpreting a study, you can’t
always read between the lines.
6
KEY POINTS
1. Three groups trained the bench press for 10 weeks, performing 7 sets of 4 reps, 4
sets of 8 reps, or 3 sets of 12 reps.
2. All three groups experienced similar pec hypertrophy. However, the groups
performing sets of 4 reps and 8 reps experienced larger strength gains than the
group performing sets of 12.
3. Gains in 1RM bench press strength were significantly correlated with gains in
pec muscle volume in the group performing sets of 12 reps, but not the groups
performing sets of 4 or 8 reps.
A
bout a year ago, Mike reviewed group doing sets of 12. An intuitive interpre-
a systematic review discussing tation of these results is that sets of 12 were
whether volume load or number of the most efficient for promoting hypertro-
sets served as a better metric for equating the phy, and that sets of 4 were the least efficient.
hypertrophy stimulus of different programs However, I’m not sure we can draw that con-
(2). In general, it seems that when compar- clusion. When interpreting research, we need
ing moderate-rep sets (sets of ~8-12 reps) to remember both what a study tests and what
and high-rep sets (sets of 20+ reps), the hy- possibilities a study leaves unexplored.
pertrophy stimulus is equated if you match
the number of sets performed. When compar-
Purpose and Hypotheses
ing moderate-rep and low-rep sets (sets of <6
Purpose
reps), there are some instances where match-
ing volume load seems to do a good job of The purpose of this study was to compare
equating the hypertrophy stimulus, and other the strength and hypertrophy effects after 10
studies where matching the number of hard weeks of training with three different loads
sets performed does a good job of equating (4RM, 8RM, and 12RM) when matching for
the hypertrophy stimulus. volume load.
The presently reviewed study (1) matched Hypotheses
volume load in three groups that performed
The authors hypothesized that strength gains
the bench press twice per week for 10 weeks.
would increase as intensity increased (4RM
One group did 7 sets of 4 reps each session,
> 8RM > 12RM) and that hypertrophy would
one group did 4 sets of 8, and one group did 3
increase as intensity decreased (4RM < 8RM
sets of 12. Hypertrophy (changes in pec mus-
< 12RM). They also hypothesized that hyper-
cle volume) was similar in all three groups,
trophy would be most strongly correlated with
while strength gains were greater in the
strength gains when training with 12RM loads.
groups doing sets of 4 or 8 compared to the
7
with seven sets per workout using a 4RM
Subjects and Methods
load, one group trained using four sets with
Subjects an 8RM load, one group performed three sets
with a 12RM load, and the final group was a
42 young, healthy men participated in this
non-training control group (which will not be
study. They had not been involved in resis-
mentioned again). All groups trained twice
tance training in the year prior to the study.
per week for 10 weeks, and rested approxi-
Experimental Design mately three minutes between sets. Interest-
ingly, the researchers ramped the subjects up
This was a relatively straightforward longi-
to their training loads gradually over the first
tudinal training study. All outcome measures
six training sessions (starting everyone at 3
were tested before and after the 10-week
sets of 10 at 60% of 1RM for the first week,
training protocol. Testing consisted of 1RM
and working up from there) to acclimate them
bench press (with grip width standardized to
to training. In the first session of week 4, the
165% of biacromial breadth, which is a pretty
4RM group tried to perform 7 sets of 4 reps
moderate grip width) and pec muscle volume
at 90% 1RM, the 8RM group tried to perform
assessed via MRI – arguably the gold stan-
4 sets of 8 reps at 80% 1RM, and the 12RM
dard for assessing changes in whole muscle
group tried to perform 3 sets of 12 reps at
size.
70% 1RM as their first “real” training session
The subjects were split into four groups via a using the experimental protocol. If subjects
counterbalancing approach (which isn’t fully were unable to complete all of the prescribed
described, but which was intended to ensure reps, they stuck with the same load until they
all four groups had similar characteristics at were able to do so; if they did successfully
baseline). One group trained the bench press complete all of the prescribed reps, the load
8
was increased by 2.5kg for the next training
session. Presumably, that’s how load increas-
es worked for the rest of the study as well.
So basically, the first three weeks involved
non-failure introductory training, with the
“real” training starting in week 4 and con-
tinuing until the end of the study.
Findings
Increases in pec muscle volume were simi-
lar in all three groups. However, bench press
1RM increased to a significantly greater de-
gree (p < 0.03) in the 4RM and 8RM groups
(28.4 ± 10.0% and 29.5 ± 11.6%, respective-
ly) than in the 12RM group (18.7 ± 10.1%).
Relative (percentage) change in pec muscle
volume was significantly associated with
relative increases in bench press 1RM in the
12RM group (r = 0.684; p = 0.042), but not
the 4RM or 8RM groups (|r| < 0.3; p > 0.75).
Volume load (sets × reps × load) was simi-
lar in all three groups, as intended. Training
loads also increased to a similar degree in all
three groups. The 4RM group averaged 3.4
± 0.3 reps per set, the 8RM group averaged
7.1 ± 0.4 reps per set, and the 12RM group
averaged 10.5 ± 0.4 reps per set.
Interpretation
Before we get into the interpretation, I want
to point one thing out about the nomencla-
ture used in this study: The authors use rep
max terminology (4RM, 8RM, and 12RM) to
label the groups, but I don’t think they were
actually training with 4RM, 8RM, and 12RM
loads. The paper isn’t completely clear about
9
how load adjustments worked, but I’m pretty mass, since you shouldn’t simultaneously be
sure the subjects just aimed for sets of 4, 8, developing the additional neural adaptations
or 12 reps, and went up in weight once they that contribute to 1RM strength (at least, not
completed all of their assigned sets without to the same degree as you would be if you
missing any reps. I don’t think they decreased were training heavier). If that’s true, that’s a
weights during each workout when subjects very useful association. Muscle growth occurs
started missing reps. If you can still get 4 reps pretty slowly – slow enough that it’s tough to
on your 7th set of 4 without reducing the load reliably detect it at home with a tape measure
on the bar, there’s no way you were using a over the short-to-moderate term. However, if
4RM. I recognize this is a somewhat pedan- you can know that strength gains are reflecting
tic point, but I think it’s worth pointing out. muscle growth if you’re training in the “hyper-
I’d suspect the subjects were actually train- trophy rep range,” you’d be in a pretty good
ing with ~5-6RM, ~9-10RM, and ~13-14RM spot, because measurable strength progress
loads, give or take. can occur over shorter time scales. A quarter
inch (~6mm) increase in thigh circumference
There were two main reasons I wanted to re-
may be within the realm of measurement error,
view this study. It provides some evidence for
but you can know if your 1RM or 10RM squat
a popular “in the trenches” method of gauging
has gone up 10 or 20 pounds. So, if you can be
hypertrophy progress. It also gives me an ex-
confident that your increased squat strength is
cuse to discuss an aspect of research interpre-
reflecting muscle growth, it helps provide you
tation that sometimes goes undiscussed: You
with peace of mind, letting you know you’re
can’t draw strong inferences about something
actually growing, even if your growth isn’t yet
a study didn’t explicitly test.
detectable with a tape measure.
One interesting finding in this study was that
When this study was published (1), I saw
strength gains in the 12RM group correlat-
several people on social media running with
ed with changes in pec muscle volume, but
that interpretation of the data. However, I
strength gains in the 8RM and 4RM groups
think we should pump the brakes on that in-
weren’t correlated with pec growth. On the
terpretation. For starters, the 8RM group was
surface, this seems to support a standard piece
also training in the “hypertrophy range,” but
of “bro” advice – if you’re training in a typical
strength gains and hypertrophy weren’t sig-
“hypertrophy” rep range, you can use strength
nificantly associated in the 8RM group. Sec-
gains as a proxy for muscle growth. Now, the
ond, the association in the 12RM group was
recommendation is generally that increases
barely significant; the p-value was 0.042;
in, say, your 10RM will correlate with muscle
flukey significant p-values that barely duck
growth if you’re training with ~10RM loads,
below the magic cutoff of 0.05 happen by
but the basic logic should extend to 1RMs as
chance all the time. Third, the subjects in this
well; if you’re not training with heavy, high-
study were untrained, so the 12RM group
ly specific loads, increases in 1RM strength
was almost certainly accruing beneficial neu-
should primarily reflect increases in muscle
10
