MASS - Volume 4 - Issue 7 - Monthly Applications in Strength Sport

115 Pages·2020·11.699 MB·English

by  Greg Nuckols, Eric Helms, Michael Zourdos, Eric Trexler

VOLUME 4, ISSUE 7 JULY 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
The Menstrual Cycle’s Effects on Performance Are
Complicated
The menstrual cycle doesn’t seem to meaningfully affect performance when
measured in the lab. However, female athletes often report that their performance
fluctuates throughout the menstrual cycle. These discrepant findings can be
primarily explained by psychological factors.
20 B Y M I C H A E L C . Z O U R D O S
Much Needed Research on Deadlift Velocity
A plethora of research has examined various aspects of velocity-based training
in the squat; however, information on the deadlift is lagging behind. This article
reviews a recent study that established a normative velocity profile in the deadlift,
investigated the reliability of deadlift velocity, and investigated the accuracy of
predicting deadlift 1RM using velocity.
32 B Y E R I C H E L M S
A Progression Framework for Hypertrophy
Hypertrophy: It’s a goal listed next to strength, power, and muscular endurance in
your textbook or professional manual, complete with ranges for each variable of
training. What assumptions does this framework require? This article takes a “first
principles” perspective on hypertrophy, using it to provide a model for progression.
44 B Y E R I C T R E X L E R
How Low Can You Go With Your Caffeine Dose?
Caffeine is great, but a 6mg/kg pre-workout dose in the afternoon can present
some jitteriness and sleep-related challenges for many people. A new study sought
to determine if we can still enjoy caffeine’s strength benefits using a fairly low dose
(<2mg/kg). Read on to find out if this low-dose strategy is a viable option.
57 B Y G R E G N U C K O L S
More Evidence Against Fiber Type-Specific Muscle Adaptations
Coaches and scientists have suggested for years that high-rep training could target
slow-twitch muscle fibers, while heavier training could target fast-twitch muscle
fibers. The results of a recent study question that claim. Heavier and lighter training
both produced similar growth in the soleus (a predominantly slow-twitch muscle)
and gastrocnemius (a muscle with a balanced fiber type ratio), whereas low-load
training should have been more effective for promoting soleus growth if low-load
training could target slow-twitch fibers.
67 B Y M I C H A E L C . Z O U R D O S
Penalty: Reduction in Gains for Interference
A new study showed that strength gains can still be made even with high amounts of
aerobic training. This article breaks down the recent data and provides a clear guide
on how you can implement cardio in a way that will have a minimal effect on your size
and strength.
81 B Y E R I C T R E X L E R
A New Meta-Analysis Says… Arginine Works Now?
Arginine has largely been written off as an ineffective supplement for exercise
performance. However, a new meta-analysis suggests that it improves both aerobic
and anaerobic performance. Did we abandon arginine too quickly? Read on to find out.
93 B Y G R E G N U C K O L S
The Evidence for Myonuclear Muscle Memory May be
Murkier Than Commonly Believed
It’s commonly believed that myonuclei – the “control centers” of muscle fibers – are
added to muscle fibers when fibers grow, but aren’t lost by fibers when they shrink,
facilitating muscle re-growth. This is a proposed mechanism for the phenomenon of
“muscle memory.” However, a recent review suggests that the data is less conclusive
than people may realize.
109 B Y M I C H A E L C . Z O U R D O S
VIDEO: Executing Iron Supplementation
Back in Volume 2, we covered the effectiveness of iron supplementation; however,
iron supplements come in various forms and with potential side effects that must be
discussed. This video picks up where we left off to discuss the execution of taking an
iron supplement.
111 B Y E R I C H E L M S
VIDEO: Evidence-Based Practice Part II
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. In part 1 of this series, we established what evidence-based practice actually
is. In part 2, we will discuss the types of evidence and their use in decision making.
Letter From the Reviewers
e passed the half-way mark of 2020 in this July issue, which covers a
W
range of topics.
On the lifting front, Greg reviewed a study on calf training - spoiler alert
- calves grow! More importantly, due to their fiber composition, they’re ideal for
studying fiber-type specific training with high or low reps. Greg also broke down
a review on muscle memory, exposing more complexity and less certainty than
previously thought. Finally, Greg reviewed a meta-analysis on the effects of the
menstrual cycle on performance, which overall, will be a relief to our readers who
have or coach those with a menstrual cycle. Working in the training department
this month, Dr. Helms wrote a concept review on progression for hypertrophy. He
examined the lenses through which we view hypertrophy training, and created a
framework for when and why to progress specific variables. To round out the training
content, Dr. Zourdos reviewed one of the few studies on the velocity profile of the
deadlift, assessing its reliability and utility for load selection. Finally, Dr. Zourdos
led the next MASS chapter on concurrent training, examining a recent study and
creating a guide for minimizing the interference effect.
Switch hitting for the nutrition department, Dr. Zourdos’ video discussed how
to implement iron supplementation. Dr. Trexler assessed a meta-analysis on the
performance enhancing effects of arginine. We learn the devil is in the methods and
the results aren’t straightforward. Dr. Trexler also reviewed a study on the minimum
effective caffeine dose for enhancing strength and endurance. Finally, Dr. Helms
finished his video series on evidence based practice, delving into the strengths and
weaknesses of different types of evidence.
We hope you enjoy this issue of MASS, and always we appreciate your commitment
to learning.
5
Studies Reviewed:
Menstrual Cycle Effects on Exercise-Induced Fatigability. Pereira et al. (2020).
Variations in Strength-Related Measures During the Menstrual Cycle in Eumenorrheic
Women: A Systematic review and Meta-Analysis. Blagrove et al. (2020)
The Menstrual Cycle’s Effects on
Performance Are Complicated
BY GREG NUCKOLS
The menstrual cycle doesn’t seem to meaningfully affect
performance when measured in the lab. However, female athletes
often report that their performance fluctuates throughout the
menstrual cycle. These discrepant findings can be primarily
explained by psychological factors.
6
KEY POINTS
1. The menstrual cycle doesn’t seem to reliably impact fatigability or muscular
performance in women with regular periods.
2. Conversely, many female athletes report that their sport performance is hindered
by menstrual cycle-related symptoms.
3. It’s possible that this apparent contradiction can be resolved by psychological
explanations.
4. Hormonal fluctuations during the menstrual cycle vary considerably between
women. While strength and fatigability during different phases of the cycle may
not vary too much on average, it’s plausible that meaningful differences could
exist on an individual level.
hroughout the menstrual cycle, the were similar (2). It doesn’t seem that strength
T
hormones estradiol and progesterone fluctuates much throughout the menstrual cy-
follow predictable cyclical patterns. cle, on average. However, since many female
Both hormones are known to have effects in athletes report that menstrual symptoms neg-
both the nervous system and skeletal muscles atively affect their performance, there’s quite
(3, 4). In fact, the muscular effects of these hor- a bit of nuance to explore.
mones seem to affect how well female athletes
respond to resistance training – training taking Purpose and Hypotheses
place during the follicular phase (between the
Purpose
onset of menses and ovulation) seems to pro-
duce more muscle growth and larger strength The purpose of the review focusing on fatiga-
gains than training taking place during the lu- bility (1) was to “summarize the effects of the
teal phase (between ovulation and the onset ovarian hormonal fluctuations on the exer-
of menses; 5, 6, 7). Thus, it’s fair to wonder cise-induced reduction in force during fatigu-
whether acute performance also fluctuates ing contractions.” The purpose of the review
throughout the menstrual cycle. focusing on strength (2) was to “systemati-
cally review the current body of research that
A pair of reviews this month investigated the
has investigated changes in strength-related
effects of the menstrual cycle on acute fati-
variables during different phases of the men-
gability and strength-related measures. The
strual cycle in eumenorrheic women.”
review focusing on fatigability (1) uncovered
studies with results that were all over the place. Hypotheses
On net, it doesn’t seem that menstrual cycle
Interestingly, the review focusing on fatigue
phase has a large effect on most measures of
did provide a hypothesis (which is uncom-
acute fatigability, though. Strength findings
mon for review articles), though the hypoth-
7
esis isn’t very specific: “Our hypothesis is 1. Subjects were women with normal menstru-
that menstrual cycle phase will influence the al cycles (21-35 days for at least 6 months).
exercise-induced decline in force, but the
2. The study assessed at least one strength-
effects with vary according to the task per-
or power-related outcome.
formed and limb used.” The review focusing
on strength-related variables did not have a 3. The outcome measure was assessed at at least
hypothesis, as one would expect. two defined points in the menstrual cycle.
4. Menstrual phase was identified or verified
Subjects and Methods
by some sort of physiological measure, such
as hormone levels or body temperature.
Since these studies were both reviews, they
had no subjects. Rather, they reviewed and
5. The study was published in a peer-reviewed
summarized previously published research.
journal.
The review on fatigue-related measures (1)
It also excluded studies that had these char-
included studies that “describe metrics of
acteristics:
motor output” and studies that, “report exer-
1. Subjects used hormonal contraception.
cise-induced reductions in force during both
the luteal and follicular phases” in women not
2. Subjects were on hormone replacement
using hormonal contraceptives. After identi-
therapy.
fying 920 possible studies in a systematic da-
3. The measures taken were separated by
tabase search, the authors narrowed the initial
longer than one regular menstrual cycle.
list to 46 studies to be included in the review.
There was no meta-analytic element of this
4. Subjects were dealing with something
review, meaning that all relevant studies were
like an injury or illness that would affect
summarized, but their results weren’t fit with
performance.
a statistical model to compute a pooled effect
5. The study didn’t adequately describe mea-
size. The review of fatigue-related measures
surement protocols or results.
never identifies itself as a systematic review,
but it appears that it is one. The inclusion cri-
6. The subjects used ergogenic aids.
teria were more lax than you generally see
After identifying 1035 potential papers in
in most systematic reviews, but that doesn’t
their search, the authors narrowed it to 21
necessarily disqualify it. The primary hall-
studies that met all criteria. From there, the
mark of a systematic review (a comprehen-
authors performed a series of meta-analyses
sive and systematic database search) is pres-
comparing strength and power performance
ent and outlined.
between the early follicular (within 5 days
The review on strength-related measures (2)
of the onset of menstruation) and ovulatory
was a systematic review and meta-analysis. To
phases (within 2 days of ovulation), ovula-
be included, a study had to meet these criteria:
tory and mid-luteal phases (21-25 days fol-
8
lowing the onset of menstruation), and early well-trained, highly trained, Collegiate, or
follicular and mid-luteal phases. A handful elite athletes. Subjects were 19-33 years old.
of studies assessed performance at other time
Table 1 shows the meta-analytic results. Note
points (e.g. mid-follicular or late luteal), but
that the “n” columns tell you the total number
not enough to warrant meta-analysis. Out-
of subjects for each comparison, not the total
comes were separated by the strength qual-
number of studies. As you can see, there are
ity assessed: maximal isometric contraction
no significant differences for any compari-
strength, isokinetic peak torque, and explo-
son, and the mean effect for all comparisons
sive strength (like jump height, peak cycling
is trivial (|g| < 0.08).
power output, or rate of force development).
The fatigue review split results out by cate-
Findings gory of performance test, including time to
task failure, relative reduction in force fol-
The studies included in the strength me-
lowing fatiguing contractions, cycling endur-
ta-analysis included a total of 232 partici-
ance time, running endurance time, and rat-
pants, with a wide range of training statuses,
ings of perceived exertion (effort-based, not
ranging from two studies on sedentary sub-
RIR-based). Somewhat confusingly, “maxi-
jects to five studies on subjects described as
mal voluntary strength” was one of the cate-
9
gories of performance included in the fatigue found that isometric handgrip time to task
review. I’m not going to include the table of failure was significantly longer in the follic-
strength studies since it would be redundant. ular phase compared to the luteal phase. No
other significant or noteworthy effects were
Nine studies with a total of 119 subjects
reported in the other six studies.
investigated the effects of menstrual cycle
phase on fatigability. One (reviewed last Six studies with a total of 187 subjects inves-
year in MASS) found that isometric knee tigated the effects of menstrual cycle phase
extension time to task failure was signifi- on strength reductions following fatiguing
cantly longer in the mid-luteal phase com- muscular contractions. One reported greater
pared to the early follicular phase, and two fatigue resistance during the follicular phase,
10