Peak week recommendations for bodybuilders: an evidence based approach

Abstract

Bodybuilding is a competitive endeavor where a combination of muscle size, symmetry, “conditioning” (low body fat levels), and stage presentation are judged. Success in bodybuilding requires that competitors achieve their peak physique during the day of competition. To this end, competitors have been reported to employ various peaking interventions during the final days leading to competition. Commonly reported peaking strategies include altering exercise and nutritional regimens, including manipulation of macronutrient, water, and electrolyte intake, as well as consumption of various dietary supplements. The primary goals for these interventions are to maximize muscle glycogen content, minimize subcutaneous water, and reduce the risk abdominal bloating to bring about a more aesthetically pleasing physique. Unfortunately, there is a dearth of evidence to support the commonly reported practices employed by bodybuilders during peak week. Hence, the purpose of this article is to critically review the current literature as to the scientific support for pre-contest peaking protocols most commonly employed by bodybuilders and provide evidence-based recommendations as safe and effective strategies on the topic.

Full text

R E V I E W Open Access
Peak week recommendations for
bodybuilders: an evidence based approach
Guillermo Escalante
1
, Scott W. Stevenson
2
, Christopher Barakat
3,4
, Alan A. Aragon
5
and Brad J. Schoenfeld
6*
Abstract
Bodybuilding is a competitive endeavor where a combination of muscle size, symmetry, “conditioning”(low body
fat levels), and stage presentation are judged. Success in bodybuilding requires that competitors achieve their peak
physique during the day of competition. To this end, competitors have been reported to employ various peaking
interventions during the final days leading to competition. Commonly reported peaking strategies include altering
exercise and nutritional regimens, including manipulation of macronutrient, water, and electrolyte intake, as well as
consumption of various dietary supplements. The primary goals for these interventions are to maximize muscle
glycogen content, minimize subcutaneous water, and reduce the risk abdominal bloating to bring about a more
aesthetically pleasing physique. Unfortunately, there is a dearth of evidence to support the commonly reported
practices employed by bodybuilders during peak week. Hence, the purpose of this article is to critically review the
current literature as to the scientific support for pre-contest peaking protocols most commonly employed by
bodybuilders and provide evidence-based recommendations as safe and effective strategies on the topic.
Keywords: Bodybuilding, Competition, Contest, Peaking
Background
Bodybuilding is a competitive endeavor where a combin-
ation of muscle size, symmetry, “conditioning”(low body
fat levels), and stage presentation are judged. To be suc-
cessful, competitors must present their best physique
during the day (or days) of the competition. Body-
builders typically employ periods of 8–22 + weeks of
preparation where diet and exercise programs are modi-
fied from the off-season in an effort to lose body fat and
gain or maintain skeletal muscle mass [1–10]. In the
final days of preparation, competitors have been re-
ported to implement interventions to “peak”their body
in an effort to maximize contest day aesthetics [11–14].
The interventions often used include altering their
exercise regimens as well as their macronutrient, water,
and electrolyte intake with the goals of: (1) maximizing
muscle glycogen content as a means to enhance muscle
“fullness”(i.e. volume), (2) minimizing subcutaneous
water (in an effort to look “dry”as opposed to “watery,”
thus enhancing muscularity), and (3) minimizing
abdominal bloating to maintain a smaller waistline and
optimize physique proportion and overall aesthetics
[11,12,14–17]. While competitors may use natural
methods to achieve these goals, self-prescription of po-
tentially hazardous drugs such as insulin and diuretics
have been widely reported [8,18–21].
An observational study gathered information on nutri-
tional peak week and competition day strategies among
81 natural bodybuilders (Males = 59, Females = 22) via a
34-item questionnaire; the survey listed commonly
utilized peaking strategies and provided additional space
for qualitative information [11]. The vast majority of the
participants (93.8 %) reported employing a peaking strat-
egy the week prior to the competition (referred to as
“peak week”), with the manipulation of carbohydrate
(CHO), water, and/or sodium most commonly reported
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* Correspondence: brad@workout911.com
6
Health Sciences Department, Lehman College, NY, Bronx, USA
Full list of author information is available at the end of the article
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[11]. The primary stated goal of CHO manipulation was
to maximize muscle glycogen concentrations by utilizing
principles similar to classical CHO loading [11]. Add-
itionally, competitors manipulated water and/or sodium
intake in an effort to induce a diuretic/polyuria effect to
flush out superfluous water [11].
In another study, researchers conducted in-depth
interviews to identify and describe different dietary
strategies used by seven natural male bodybuilders
during the off-season, in-season, peak week, and post-
season [14]. During peak week, six participants re-
ported using a modified carbohydrate loading regimen
to attempt to increase glycogen content. Furthermore,
all participants reported manipulating water intake
while three simultaneously manipulated sodium intake
in an attempt to reduce body water in hopes of creat-
ing a leaner look [14].
Although many peak week protocols exist that attempt
to enhance aesthetics, research is lacking in regards to
the efficacy and safety of the methods commonly used
by bodybuilders. Among enhanced bodybuilders, the
self-prescription of drugs such as insulin and diuretics
have been reported with potentially dangerous outcomes
[18–21]. The purpose of this article is to: (1) review the
current literature as to the peaking protocols most com-
monly employed by bodybuilders; (2) provide evidence-
based recommendations as to pre-contest peaking strat-
egies for competitors and coaches.
Main Text
Carbohydrate Manipulation
Manipulation of carbohydrate intake is a popular pre-
contest peaking strategy among bodybuilders [11,12,
14]. The strategy, generally employed during the week
prior to competition, involves substantially limiting
carbohydrate intake for several days (often referred to as
depletion phase) followed by a brief period of high-
carbohydrate consumption, with the goal of achieving a
supercompensation of glycogen levels when carbohy-
drate is “loaded”[22]. Resting muscle glycogen levels
with a mixed (normal) diet are ~ 130mmol/kg muscle
(wet weight) in trained individuals (a bit higher than
sedentary subjects) [23], or roughly 23 g of glycogen
(glucosyl units) per kilogram of muscle tissue. Muscle
glycogen is organized in the cell in subcellular fractions
[24] and stored as a glycogen-glycogenin complex
(“granule”)[25] which creates an osmotic effect of pull-
ing water into the cell as glycogen is stored [26,27],
thereby increasing muscle cell volume. Early research
suggested that each gram of muscle glycogen stored is
accompanied by approximately 3–4 g of intracellular
water [28]. This is higher than the commonly referenced
value of 2.7 g of water per gram of glycogen, sometimes
rounded to 3 g of water per gram of glycogen, which is
derived from studies of rat liver [29,30]. However, the
resultant muscle glycogen levels after glycogen loading is
highly variable [31], perhaps due to the complexity
underlying intramuscular glycogen storage [25]. Simi-
larly, while it is clear that glycogen loading can increase
intracellular water content [31], muscle thickness [15],
and lean body mass (LBM) estimates [32], the relative
extent of intracellular hydration in grams of water per
gram of glycogen may vary so greatly that it is not statis-
tically correlated with glycogen content [30].
Although controlled research on the topic is limited
for what is optimal for bodybuilders, current evidence
does appear to indicate a potential benefit of carbohy-
drate manipulation as a peaking strategy. A case series
by Bamman et al. comprising six male bodybuilders pro-
vided initial support of a beneficial effect [1]. The body-
builders reportedly engaged in a carbohydrate-loading
protocol three days prior to competing (mean intake of
~ 290 g/day). Ultrasound measurements taken 24–48 h
into this carbohydrate loading period showed a 4.9 % in-
crease in biceps brachii muscle thickness when com-
pared to measures obtained six weeks earlier. While
these findings seem to suggest that the carbohydrate
loading protocol was effective in acutely enhancing
muscle size, it should be noted that the long gap be-
tween testing sessions makes it impossible to draw infer-
ences as to causality in this regard. Moreover, the
authors of the study did not assess carbohydrate intake
during the carbohydrate depletion phase, further cloud-
ing the direct effects of the loading protocol. Thus, while
results are intriguing, the level of supporting evidence
can be considered low.
A recent quasi-experimental trial by de Moraes et al.
[15] sheds more objective light on the topic. Twenty-
four high-level amateur male bodybuilders were strati-
fied based on whether or not they manipulated carbohy-
drate as a peaking strategy; the group that manipulated
carbohydrate employed a three day depletion phase
(leading immediately up to the weigh-in day) followed
by a 24-hour loading phase (leading up to competition
day). Muscle thickness was measured both at weigh-in
and the day of competition. In addition, photos of the
competitors taken at these time points were shown to a
group of federated bodybuilding judges, who subjectively
assessed their physiques; of note, judges were blinded to
the competitors’nutritional practices. Results showed a
3 % increase in muscle size of the upper arms for those
who manipulated carb intake prior to competition versus
no change in those who did not. Moreover, only the
group that manipulated carbohydrate intake showed im-
provements in subjective aesthetic measures as deter-
mined by visual inspection of photos. A potential
limitation of the study is that subjects were not drug-
tested prior to competition; thus, it remains unknown as
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to whether the use of anabolic steroids and/or other syn-
thetic substances (i.e., synthol) may have influenced re-
sults. Future studies should ascertain via self-report,
polygraph and/or blood testing the drug-free/enhanced
status of subjects and exclude or compare results based
on subject steroid use as well as use of other drugs that
may influence water balance (e.g., caffeine - see below).
Recently, members from our group (Schoenfeld and
Escalante) carried out a case study where we followed a
high-level natural bodybuilder over the course of his
contest preparation [33]. Beginning 1-week prior to the
date of competition, the competitor markedly reduced
carbohydrate intake to < 50 g/day for 3 days (Sunday,
Monday, Tuesday) and then loaded carbohydrate to >
450 g/day over the ensuing 2-day period (Wednesday
and Thursday). Similar to previous research, ultrasound
assessment showed that the peaking strategy acutely in-
creased muscle thickness. In this particular case study,
increases were 5 % in the upper extremities and ~ 2 % in
the lower extremities; due to the limited available evi-
dence, it is difficult to provide a rationale as to why there
was a difference between the muscle groups. Given the
subjective findings reported by de Moraes et al. [15], it
can be inferred that these results likely were practically
meaningful from a competition standpoint.
When considering the totality of current research, evi-
dence suggests that carbohydrate manipulation is a vi-
able peaking strategy to enhance muscle size on contest
day; however, the evidence should be considered prelim-
inary given the relative dearth of published studies on
the topic. Moreover, the strategy may bring about an in-
crease in gastrointestinal symptoms such as abdominal
pain, heartburn, constipation, and diarrhea [15], which
in turn may negatively affect the ability to perform opti-
mally on contest day. Thus, competitors should experi-
ment with the strategy at least 2–4 weeks in advance to
determine its effects on an individual level and make
relevant adjustments as needed.
Water and Sodium Manipulation
Water and sodium are frequently manipulated by body-
builders, either independently or concurrently, employ-
ing a variety of strategies involving “loading”and
restricting both [11], with the goal of minimizing sub-
cutaneous water to maximize the underlying skeletal
muscle definition [8,11,12,14,19,20]. Bodybuilders
have been reported to self-prescribe potentially danger-
ous pharmaceutical diuretics to facilitate the process [8,
19–21,34,35]. Bodybuilders may also employ these
strategies to drop down to lower weight classes, which
can provide a competitive advantage if the competitor is
able to regain some of weight in the form of intramyo-
cellular volume (“filling out”via glycogen and/or intra-
myocellular triglyceride storage) prior to competition.
Although water and sodium are two separate dietary
components, it is critical to comprehend that manipula-
tion of one variable influences the other; hence, we will
review these two variables together.
In a previously referenced survey on peak week and
competition day strategies used by natural bodybuilders,
water manipulation was the second most popular strat-
egy implemented (behind carbohydrate manipulation)
[11]. Researchers reported that competitors imple-
mented water loading (65.4 %), water restriction (32.1 %),
or both (25 %) to achieve a “dry”look. The amount of
water consumed during the loading phase ranged from 4
to 12 L per day and was typically followed by water re-
striction 10–24 h prior to the competition. In addition
to water manipulation, researchers also reported that
competitors utilized sodium restriction (13.6 %), sodium
loading (18.5 %), or both (6.2 %) with no consistent tem-
poral order for the sodium loading/restriction regimen;
however, sodium manipulation was generally practiced
three to four days prior to competing. The use of dande-
lion tea was also reported due to its purported diuretic
properties (see dietary supplementation section below).
In the previously discussed study by Mitchell et al.
[14], researchers reported that 100 % of participants (n =
7) utilized the practice of water loading and water cut-
ting during peak week. This strategy involved drinking >
10 L of water per day early in the week and then redu-
cing the intake each subsequent day leading up to the
competition. The theory behind this practice was to con-
sume superfluous amounts of water to naturally increase
fluid excretion in an attempt to preferentially excrete
subcutaneous water; however, the participants reported
that the results of this strategy were largely ineffective
[14]. Out of the seven participants that manipulated
water during peak week, three (42.8 %) also manipulated
sodium to help remove subcutaneous water [14]. They
reported greatly increasing sodium intake for the first
three days of peak week followed by a complete restric-
tion of salt intake for the three days prior to the compe-
tition; however, results were inconsistent and the
participants stated they would not manipulate sodium in
the future [14]. Note that the participants’unanimous
decision to abandon these water and sodium manipula-
tion strategies suggests they had likely neither performed
nor refined them previously (e.g., as a trial run or during
peak week for another competition).
Other research supports the findings of the aforemen-
tioned studies. Probert et al. conducted a survey of 382
competitive bodybuilders along with personal interviews
of 30 of the participants and reported that bodybuilders
frequently engaged in the practices of sodium depletion
and dehydration in the days prior to competing [12]. Al-
though participants acknowledged the risks of these
strategies, they downplayed them as temporary but
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necessary practices [12]. Indeed, case reports document
potentially life-threatening conditions due to extreme
practices of water and sodium manipulation [19,20]. In
one case, a 35-year-old male bodybuilder reported to the
emergency room after feeling weak, dizzy, and experien-
cing painful muscle cramps while posing during a body-
building competition; tests revealed peaked T-waves on
the electrocardiogram (ECG), hyperkalemia (high potas-
sium levels), hyponatremia (low blood sodium levels),
water intoxication, and rhabdomyolysis [20]. The body-
builder reported drinking 12 L of water per day for
seven days prior to the competition along with 100 mg
daily of spironolactone (a potassium-sparing prescription
diuretic) and salt depletion for two days prior to compe-
tition; he was successfully treated, stabilized, and dis-
charged [20]. In another case, a professional 26-year-old
male bodybuilder was transported to the emergency
room the day after a competition as a result of heart pal-
pitations and an inability to stand due to difficulty in
moving his extremities [19]. He reported oral intake of
2 × 80 mg of furosemide (a prescription loop-diuretic)
24- and 48 h before the competition with the goal to en-
hance muscle definition; he lost 5–6 kg of bodyweight
due to nocturia [19]. Tests revealed severe hypokalemia
(low potassium levels; as opposed to hyperkalemia in the
previously discussed case study likely due to the use of a
loop-diuretic vs. a potassium sparing diuretic), hypergly-
cemia (high blood glucose levels), hyperlactatemia (high
blood lactate levels), and sinus tachycardia with pro-
nounced U waves on ECG consistent with hypokalemia
[19]. Although hypokalemia is a potentially life-
threatening condition, the bodybuilder was treated suc-
cessfully and discharged the next morning [19].
Despite the various strategies reported by bodybuilders
to manipulate water and sodium for the purposes of
looking “full and dry,”current evidence does not indicate
that these practices are specifically effective and/or safe.
Additionally, although several water and sodium ma-
nipulation strategies have been published by a number
of bodybuilding coaches who have worked with highly
successful bodybuilders [16,17,36], neither the efficacy
nor safety of these varying methodologies have been sci-
entifically evaluated. Hence, physiological principles of
body fluid regulation must be considered when attempt-
ing to formulate strategies to promote a “full and dry”
appearance, and these strategies may be discordant with
those currently used by bodybuilders and/or suggested
by their coaches.
Total body water (TBW) content accounts for ap-
proximately 60 % of an average person’s body weight
and is made up of intracellular water (ICW) (~ 67 %)
and extracellular water (ECW) (~ 33 %). ECW is further
compartmentalized into interstitial fluid that surrounds
the cells (~ 25 %) and blood plasma (~ 8 %) [37,38].
Hence, from a bodybuilder’s perspective, minimizing the
extracellular interstitial fluid that surrounds the myo-
cytes, specifically subcutaneous water, while preserving
or increasing the intramyocellular ICW represents the
ideal scenario for a “full and dry”appearance, i.e.,
whereby the appearance of muscularity is maximized.
While this concept may seem like a simple task to ac-
complish by manipulating water and sodium alone, other
strategies focused on optimizing intramyocellular vol-
ume (i.e., those targeting intramyocellular glycogen, tri-
glyceride, and potassium content) may need to be
considered along with the manipulation of water and so-
dium for the appearance of muscularity to be enhanced.
During normal fluid-electrolyte homeostasis, the extra-
cellular compartment contains most of the sodium (Na+
), chloride (Cl
−
), and bicarbonate (HCO
3
−
), whereas the
intracellular compartment contains most of the water,
potassium (K+), and phosphate (PO
43−
)[39]. Although
both compartments contain all of the aforementioned
compounds, the quantity of each varies between the
compartments such that the total concentration of sol-
utes (osmolarity) is the same [39]. Homeostatic mecha-
nisms control water and electrolyte balance to ensure
TBW and total body osmolarity (TBO) remain balanced
and water redistributes itself between the intracellular
and extracellular compartments such that the osmolarity
of bodily fluids approximates TBO [37]. Indeed, Costill
et al. investigated muscle water and electrolyte losses
while participants cycled in a hot environmental cham-
ber to lose 2.2 % (stage 1), 4.1 % (stage 2), and 5.8 %
(stage 3) of their body weight over an estimated 5.5 h
period [40]. When participants lost 2.2 % of their body
weight within the first ~ 1.5 h in stage 1, 30 % of the
water lost was ICW while 70 % was ECW [40]. However,
the ratio of ICW to ECW lost became 52 % ICW/48 %
ECW at stage 2 (~ 3.5 h mark) and 50 % ICW/50 %
ECW at stage 3 (~ 5.5 h mark) [40]. The authors stated
that the large loss of ICW in muscle at stage 1 may be
explained by the significant loss of muscle glycogen con-
tent (which contains water) from pre-dehydration at 115
mmol/kg down to 76 mmol/kg; however, muscle glyco-
gen content levels dropped at a much lower rate to 73
mmol/kg at stage 2 and 61 mmol/kg at stage 3 as the ra-
tio or ICW:ECW stabilized [40]. Hence, the ratio of
ECW to ICW loss appears to stay close to 1:1 as glyco-
gen levels stabilize over time and higher levels of dehy-
dration are reached. Thus, it seems that retention of
muscle glycogen, by avoiding exercise that relies heavily
on glycogen usage, may be important if methods of
water loss are to effect a favorable loss of ECW relative
to ICW (ECW > ICW) such that muscle size is retained
while interstitial ECW is preferentially lost, enhancing
the appearance of muscle “definition.”Relatedly, storage
and retention of muscle glycogen is highly dependent on
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potassium availability (a primary intracellular cation -
see above) [41–46], so ensuring adequate potassium in-
take during both carbohydrate loading and dehydration
procedures seems paramount to optimizing stage
appearance.
Importantly, if alterations in plasma osmolarity (via
changes in total body water and electrolytes) reach a
physiological threshold, then a complex neuroendocrino-
logical network throughout the body in the brain, blood
vessels, kidneys, and endocrine glands will respond to
stabilize it [47]. Plasma osmolarity is affected by changes
(increase or decrease) in the concentration of solutes
(i.e., sodium) in the blood as well as changes in fluid vol-
ume; fluid volume is affected by total body water (TBW)
[48]. Plasma osmolarity can increase by an excessive loss
of water or a significant increase in sodium intake; con-
versely, plasma osmolarity can decrease with insufficient
electrolyte consumption or excessive water intake [49].
Plasma osmolarity and blood pressure are regulated such
that increasing plasma osmolarity results in decreased
blood pressure and vice versa [49]. Additionally, blood
pressure changes mediated by shifting plasma osmolarity
are countered by arterial and renal baroreceptors [50].
During dehydration, as might be employed during
peak week, plasma osmolarity increases, blood pressure
decreases, and the renal baroreceptors in the juxtaglo-
merular apparatus (JGA) release the hormone renin; in
turn, this activates the renin-angiotensin-aldosterone
system (RAAS) [51]. When RAAS is activated, the
process of maintaining fluid, electrolyte, and blood pres-
sure homeostasis is initiated [51] and eventually releases
the hormone aldosterone from the adrenal glands to fur-
ther fine tune homeostasis [52,53]. The baroreceptors
in the aorta and carotid arteries also detect a decrease in
blood pressure and signal the release of antidiuretic hor-
mone (ADH, also known as vasopressin) from the pituit-
ary gland to conserve water, increase blood volume, and
increase blood pressure [48]. Conversely, if blood pres-
sure increases due to increased arterial blood volume,
the heart atria sense a stretch and release the hormone
atrial natriuretic factor (ANF) to increase sodium excre-
tion, inhibit renal vasoconstriction, attenuate renin se-
cretion, and ultimately decrease blood volume and blood
pressure [54].
Collectively, if water and sodium are not carefully ma-
nipulated and timed, these physiological mechanisms
that work to keep the body in homeostasis may not
bring about the desired effect of selectively reducing
fluid in the extracellular/subcutaneous space. Although
these mechanisms are in place to keep the body in bal-
ance, not all hormones released have an immediate ef-
fect on the body when plasma osmolarity is altered. For
example, a study displayed a delayed effect of ADH
when investigators examined the effects of water loading
on acute weight loss in combat sport athletes by com-
paring a water loading strategy for three days where the
experimental group consumed 100 ml/kg/day of water
compared to a control group that consumed 40ml/kg/
day of water [55]. During the subsequent day of dehy-
dration with both groups consuming 15ml/kg/day of
water, the ADH levels in the water loading group rose
from ~ 2.3 pmol/L to ~ 3.8 pmol/L at the 13th hour and
~ 5 pmol/L at the 24th hour of fluid restriction, at which
time body mass losses exceeded those of the control
group by 0.6 % (~ 2.5 vs. 3.1 % compared to baseline)
[55]. Thus, despite the increased total fluid output from
3 days of water loading combined with one day of dras-
tic fluid restriction, ADH levels were still climbing over
24 h of dehydration [55]. In another study, investigators
reduced sodium intake to extremely low levels (10 meq/
day) for ~ 6 days in 16 healthy men and measured the
RAAS, plasma aldosterone, urine sodium, and serum so-
dium levels at 24 h, 48 h, and ~ 6 days after the inter-
vention [53]. Although serum sodium levels remained
fairly consistent between 137.6 and 139 meq/l for the ~
6 day period, researchers reported that the RAAS activa-
tion was evident within 24 h and decreased urine so-
dium output from 217 meq/24 hr down to 105 meq/24
hr [53]. Furthermore, it took 48 h to observe a sharp in-
crease in plasma aldosterone levels to further decrease
urine sodium output to 59 meq/24 hr and another ~ 4
days for urine sodium output to stabilize at 9.9 meq/24
hr [53]. Hence, there is a temporal lag in establishing
fluid and electrolyte homeostasis during which water
and sodium manipulation may be implemented to in-
duce diuresis before the protective homeostatic mecha-
nisms fully manifest to halt water loss.
While bodybuilders often manipulate water and/or so-
dium by altering their intake [8,11,12,14,19,20], an-
other viable strategy may also be considered to increase
diuresis. The literature on disuse atrophy and cardiovas-
cular adaptations to weightlessness during space flight
[56] reveals a previously described strategy [36] that
physique competitors may employ to promote diuresis
during the ~ 24 h before competition. Resting and/or
sleeping with a “head down tilt”(HDT) position (typic-
ally −4to-6˚whereby the entire sleeping surface is
downsloping [57,58] simulates the increase in cardiac
venous return (and loss of orthostatic pressure) that oc-
curs during microgravity. This results in diuresis and
cardiovascular responses similar to those observed
acutely during space flight [57,59], mediated in part by
an increase in atrial natriuretic peptide (released from
the heart) and reduced plasma renin [60,61]. Mauran
et al., for instance, demonstrated that these hormonal re-
sponses and the associated diuresis and natriuresis re-
turn to baseline within 24 h [62], evoking a body weight
loss of approximately 1.0-1.3 kg without changes in
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resting heart rate or blood pressure [58,60,61]. Short
periods of more severe HDT up to -30 % evoke graded
increases in central venous pressure beyond those of
-6 % HDT [63], although the diuretic responses to HDT
angle less than −6 % have not been studied to our know-
ledge. Brief (≤2 h) periods of HDT up to -40˚seem well
tolerated [64,65], but prolonged HDT at angles ≤-12 %
increases intracranial and intraocular pressure signifi-
cantly [66]. Additionally, sufferers of gastric reflux
should be aware that HDT could conceivably worsen
symptomatology, given that elevating the head above
bed level (the opposite of HDT) is an effective remedy
[67–70]. This is likely not an issue for those who do not
normally experience gastric reflux [71]. Thus, competi-
tors could conceivably employ HDT when resting and
sleeping during the 12-24 h before competition to fur-
ther encourage diuresis as needed.
Another consideration when manipulating water and
sodium intake is the important roles they play in carbo-
hydrate absorption. Sodium-glucose dependent cotran-
sporters (SGLTs) are proteins found in the small
intestine that allow for glucose to be transported across
the cell membrane; strong evidence suggests that the de-
livery of carbohydrate transport is limited by the trans-
port capacity of SGLT1 [72–75]. Since carbohydrate
loading appears to have potential benefits for body-
builders to appear “full,”availability of sodium for co-
transport of glucose across the cell membranes is im-
portant. Interestingly, the study by de Moraes et al. re-
ported that carb loading induced various gastrointestinal
symptoms in competitive bodybuilders [15]. Although
sodium intake was not reported in this study, some of
the symptoms may have been due to a lack of dietary so-
dium since bodybuilders have reported minimizing so-
dium intake as they approach contest day [11,14,20].
Additionally, since each gram of glycogen draws ~ 3–4g
water into the muscle [31] and this is a potassium
dependent process (see above), a lack of water and po-
tassium intake may also reduce the effectiveness of
attaining a “full”appearance.
Contrary to the typical goal of reducing (extracellular,
subcutaneous) body water, psychological disturbance/
emotional stress can cause the retention of body fluids
[76] via the actions of catecholamines (particularly dopa-
mine) [77–79] and adrenocortical hormones, including
both cortisol [80] and aldosterone [81]. Water retention
during experimental stressful conditions requiring com-
petition is subject to inter-individual variability, perhaps
due in part genetic differences [82]. In extreme cases,
emotionally stressful situations can evoke polydipsia and
alter fluid homeostasis such that increases of up to 9 kg
(~ 20lb) of body mass can accrue in as little as 48 h [78,
79]. Thus, there is support for the common empirical
observation that psychological stress may counteract the
competitive bodybuilder’s attempts to reduce body
water, especially in extreme cases of pre-competition
anxiety. The authors recommend performing a practice
run of the peak week strategy ~ 2–4 weeks before the ac-
tual competition, in part to reduce anxiety and assure
the competitor that the peak week strategy is both man-
ageable and effective. Although beyond the scope of this
article, stress management is acknowledged as an im-
portant aspect of sport psychology [83,84] and is very
likely important for competitors who find the final days
before competition so stressful that it negatively affects
on-stage appearance.
Based on these principles of water-electrolyte balance
and the current evidence available, it appears that the
manipulation of water and sodium should be carefully
considered, planned, and practiced in conjunction with
carbohydrate manipulation if they are to be utilized.
While there appear to be some potential benefits to
implementing these strategies to enhance the
competition-day physique, potentially detrimental effects
may occur if these variables are miscalculated and/or
mistimed that may cause bodybuilders to miss their peak
and/or incur health problems; thus, leaving these vari-
ables alone may be a better option for some competitors.
Since bodybuilders have been reported to view sodium
and water manipulation as temporary but necessary
practices while downplaying the potential risks involved,
caution must be practiced as extreme measures have
been reported that led to life-threatening conditions [12,
19,20]. The practical applications sections of this article
will further outline how these variables may be safely
manipulated based on the current evidence available.
Dietary Fat
In addition to glycogen, muscle cells also store energy as
intramuscular triglycerides (IMT). Indeed, nearly as
much energy is stored in muscle cells as IMT as is
stored as glycogen [85]. However, IMT stores vary con-
siderably in humans, in part as a function of training sta-
tus, muscle fiber type, insulin sensitivity, gender, and
diet [85]. IMT may amount to ~ 1 % of muscle weight
[86,87], but because fat is less dense than skeletal
muscle [88], the volume of IMT in a fully “fat-loaded”
muscle cell could exceed 2 % of muscle volume [89,90].
In rats (17), a single exercise bout can decrease muscle
IMT content by 30 %, and three days of a high fat diet
can boost IMT storage by ~ 60 % above baseline [91]. In
humans, the dietary replenishment of IMT may be
slower when glycogen restoration is also a priority [89,
92–94]. Still, IMT stores are increased by dietary fat in-
take [91,95] and reduced during resistance [96] and en-
durance exercise [85].
Although fat loading has been a known strategy in
bodybuilding circles for many years [97,98], to our
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knowledge the strategy has not been studied directly in a
bodybuilding peak week context (e.g., in combination
with other dietary strategies such as glycogen supercom-
pensation). In the rodent study mentioned above [91],
three days of a high fat diet followed by three days of a
high carbohydrate (CHO) diet resulted in supercompen-
sation of both IMT and glycogen; however, 6 days of
only a high CHO produced the expected glycogen load-
ing effect but failed to elevate IMT levels above baseline.
In humans, high CHO/low fat diets may actually precipi-
tate a reduction of IMT stores [92–94], perhaps because
IMT is used preferentially to cover the energetic costs of
post-exercise cellular repair and glycogen-glycogenin as-
sembly [94,99]. Considering that a large (e.g., heavy-
weight male) bodybuilder may carry over 60 kg of
muscle [100,101], increasing IMT stores from a rela-
tively “depleted”to a “loaded”state could conceivably in-
crease muscle volume by > 1 % [85]; hypothetically, this
translates to adding ≥0.6 kg of fat free mass. Hence, fat
loading appears to be a promising strategy to be used in
conjunction with CHO loading during peak week for
bodybuilders, and thus warrants future study in a con-
trolled setting.
Dietary Protein
In conjunction with carbohydrate and fat intake during
peak week, optimizing protein intake warrants discus-
sion, as it is a major and indispensable component of
the diet. The U.S. Recommended Dietary Allowance
(RDA) for protein for adults is 0.8 g/kg [102], and has
remained unchanged since ~ 1980, despite ongoing ex-
posure of its inadequacy. In a call to re-evaluate and re-
vise the RDA, Layman [103] contended that protein
requirements are inversely proportional to energy intake.
The latter point applies to dieters in general, but it has
special significance for athletes in prolonged hypocaloric
conditions, epitomized by pre-contest physique competi-
tors. In light of mounting evidence, a daily intake of 1.2–
1.6 g/kg has been proposed as optimal for the general
population aiming to optimize health and longevity
within a physically active lifestyle [104]. Toward the
more athletic end of the spectrum, in the most compre-
hensive meta-analysis of its kind, Morton et al. [105]
found that a protein intake of ~ 1.6 g/kg (upper 95 % CI
of 2.2 g/kg) maximized muscle hypertrophy and strength
in non-dieting recreational resistance trainees. In a study
more representative of bodybuilders, Bandegan et al.
[106] assessed whole-body protein synthesis via the indi-
cator amino acid oxidation (IAAO) method and deter-
mined an Estimated Average Requirement of 1.7 g/kg/d
with an upper 95 % confidence interval of 2.2 g/kg/d to
be near their maximal attainable muscularity. In a simi-
lar protocol using the IAAO method, Mazzulla et al.
[107] estimated the protein requirements of resistance-
trained men to be 2.0-2.38 g/kg.
A systematic review by Helms et al. [108] reported that
2.3–3.1 g/kg of fat-free mass (FFM) was appropriate for
resistance-trained subjects in hypocaloric conditions.
However, out of the six studies included in the review,
only two involved highly-trained competitive athletes,
and only one study examined competitive bodybuilders.
The latter study was conducted by Mäestu et al. [109],
who tracked the body composition and hormonal profile
of national and international level bodybuilders during
the final 11 weeks of contest preparation. The competi-
tors self-reported being steroid-free for a minimum of
two years prior to the study. Protein intake was 2.68 g/
kg (2.97 g/kg FFM) at baseline and 2.48 g/kg (2.66 g/kg
FFM) at the final assessment point (3 days pre-contest).
Chappell et al. [2] reported that in high-level drug-free
bodybuilders, end-of-preparation protein intakes of men
and women who placed in the top-5 were 3.3 g/kg and
2.8 g/kg, respectively. Body composition was not re-
ported in this study. Based on typical body fat percent
ranges at the end of preparation, adding 4–6 % to the
men’s intake and 13–15 % to the women’s intake would
provide an estimate of grams of protein consumed per
kg of FFM. A case study by Kistler et al. [3] on a high-
level drug-free champion bodybuilder reported a protein
intake of 3.4 g/kg (3.6 g/kg FFM). While the descriptive
nature of these studies precludes the ability to draw in-
ferences as to whether the observed level of intake was
beneficial, neutral or detrimental from a physique stand-
point, they appear to converge upon similar protein dos-
ing in the final stage of the pre-contest period.
A potential consideration for protein dosing during
peak week is whether to keep protein intake static or
alter it during the carbohydrate depletion and loading
phases. While no concrete evidence currently exists as
to what is optimal to our knowledge, the study by de
Moraes et al. [15] that reported an increase in muscle
volume and enhanced physical appearance as a result of
a carbohydrate-loading protocol provides some evidence
that bodybuilders alter their protein intake during peak
week. In this study, the depletion/loading protocol was
three days of a low-carbohydrate (1.1 g/kg) and high-
protein (3.2 g/kg) diet followed by only one day of a
high-carbohydrate (9.0 g/kg) and low-protein (0.6 g/kg)
diet. It seems likely that similar increases in muscle vol-
ume would have occurred if protein was kept static.
However, despite the decreased protein intake (46.6 g on
the carbohydrate-loading day versus 252.4 g on the
carbohydrate depletion days), gastrointestinal distress
was still significantly greater than the non-carb-loaded
control group. This points to the possibility that keeping
protein intake high during the loading day would have
further worsened gastrointestinal symptoms, potentially
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due to excessive food intake. An alternative would be to
keep protein static, but lessen the carbohydrate load
(which in this case was ~ 714 g), allowing more than
1 day for carbohydrate loading. This seems a more prac-
tical approach (see above), such that an even greater
total carbohydrate intake could be consumed but with
less risk of gastrointestinal issues.
A potentially viable strategy of altering protein in-
take during peak week is to keep protein intake rela-
tively high at ~ 2.5–3.5 g/kg/day during the initial ~ 3
days of glycogen depletion portion of a glycogen
super compensation strategy, followed by a relatively
lower protein intake of ~ 1.6 g/kg/day during a high
carbohydrate diet for 1–3days(seeabove),finishing
at least 24 h before the scheduled competition.
Thereafter, a strategy for inducing diuresis and (fur-
ther) elevating IMT stores during the day preceding
competition by following a high protein, low carbohy-
drate (high fat) diet for a short period (~ 12–24 h)
could be employed. As previously discussed, when
carbohydrate loading using a low fat approach, IMT
levels may decline, but elevated glycogen levels persist
for several days in lieu of glycogen-reducing, demand-
ing contractions (e.g., resistance exercise or excessive
posing). High levels of intramuscular glycogen and
the associated intracellular water would thus prevent
the loss of ICW that typically accompanies diuresis.
Increasing protein intake consumed the day before
the show, or simply consuming protein at the high
levels typically employed by pre-contest bodybuilders
(~ 3.0–3.5 g/ kg / day; see above) and shown recently
to be generally safe over longer periods [110], will en-
courage greater oxidative deamination of amino acids
and ureagenesis [111]thatapproximatethemaximal
rates observed in healthy individuals [112,113]. Clear-
ance of blood urea in turn requires an osmotic gradi-
ent during its renal excretion, thus causing diuresis
[114,115]. Additionally, reverting back to a lower
carbohydrate diet (e.g., one similar to that used early
in the week to fat load in preparation for carbohy-
drate loading) would also promote loss of body water
[116,117]. Thus, increasing or maintaining a high
protein intake while lowering carbohydrate and con-
comitantly increasing fat intake during the day before
competing would reverse unwanted gains in extracel-
lular/subcutaneous water experienced during carbohy-
drate loading [118]. It would also complement other
strategic measures designed to induce diuresis such as
manipulation of water/sodium/potassium intake, diet-
ary supplementation, and body positioning (e.g.,
HDT) that would also afford a second opportunity for
fat loading during peak week. Uncertainty of the ef-
fectiveness of modifying the de Moraes et al. and
other protocols can only be mitigated by trial and
error, as will be further discussed in the practical ap-
plications section, and warrants further scientific
investigation.
Dietary Supplementation
The consumption of sport supplements is common
among bodybuilders and is often manipulated through-
out their training phases (i.e. off-season, pre-contest) [2,
3,5]. Although it is well understood that physique ath-
letes utilize supplements such as protein powder, proc-
essed carbohydrates, pre-workout stimulants and
ergogenic aids, creatine, vitamins/minerals, omega-3’s,
thermogenics, diuretics and much more [2,7], there is a
paucity of data on how these supplements affect the ath-
lete’s peaking process to enhance their physique. Hence,
we will discuss the potential benefits of utilizing refined
food supplements (i.e. protein/carbohydrate powders,
fatty acids), creatine, and herbals during peak week.
Energy yielding food supplements like protein and
carbohydrate have been regularly reported by other re-
searchers examining bodybuilders [2,3,5]. Chappell
et al. [2] examined fifty-one (35 male & 16 female) nat-
ural bodybuilders and found that ~ 75 % of males and ~
89 % females supplemented with protein powders.
Carbohydrate supplementation was less popular, with
just ~ 37 % of the male competitors and no female com-
petitor reporting their use. Bodybuilders may utilize
these nutritional supplements as a means to manipulate
and consume specific macronutrient quantities. As pre-
viously mentioned in the carbohydrate and water/so-
dium sections, bodybuilders seek to maximize muscle
glycogen and its associated osmotic effect as a means to
increase total muscle volume. Thus, it is common to
supplement with various carbohydrate powders (e.g.
dextrose, highly-branched cyclic dextrin, etc.). Carbohy-
drate characteristics such as osmolality, gastric clearance
rate, and glycemic index are some of the variables phys-
ique athletes should take into consideration as these can
significantly vary between sources and may impact
gastrointestinal symptoms (e.g. bloating, cramping, diar-
rhea, constipation, etc.) [119–121]. Furthermore, the gly-
cemic index of different carbohydrate sources have been
shown to impact glycogen synthesis rates [122,123].
This may be of greater importance for bodybuilders who
are aiming to refill glycogen stores in a short time
window (e.g. after making weight), as high glycemic car-
bohydrates have demonstrated superior glycogen resyn-
thesis rates [122]. However, over a longer timeframe (i.e.
8 + hours), glycogen stores can be replenished similarly,
regardless of feeding frequency [124], when consuming
an adequate total amount of carbohydrates [125]. Add-
itionally, data have demonstrated that combining protein
with carbohydrates can enhance glycogen resynthesis
[126]. However, it seems prudent that athletes do not
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“experiment”during peak week with new CHO, protein
sources, or other supplements not integral to peak week
specific strategies to reduce the risk of experiencing
negative gastrointestinal symptoms or any other deleteri-
ous consequences.
There is substantial evidence supporting the use of
creatine supplementation for bodybuilders. Chappell
et al. reported that ~ 48 % of males and ~ 51 % of fe-
males supplemented with creatine during their contest
preparation [2]. Creatine has been shown to improve
body composition (i.e. increase lean body mass, decrease
fat mass) [127,128] and increase intracellular hydration
status [129,130]. Ziegenfuss et al. [129] demonstrated
that a three day creatine loading phase increased intra-
cellular fluid volume by ~ 3 % without impacting extra-
cellular fluid. The use of multifrequency bioelectrical
impedance analysis (MBIA) caused some to initially in-
terpret the data with some skepticism. However, a
follow-up study employing the same three day creatine
loading scheme observed a 6.6 % increase in thigh
muscle volume among elite NCAA power athletes as de-
termined by the gold-standard magnetic resonance im-
aging [131]. Creatine supplementation has also been
shown to aid in glycogen synthesis and supercompensa-
tion [132]. Additionally, consuming CHO with creatine
increases creatine loading [133], which increases cellular
hydration as noted above [32,129]. Finally, muscle creat-
ine levels decline very slowly after loading [134], so cre-
atine intake after peak week glycogen loading is not
needed except perhaps in small amounts to potentially
accelerate last minute, competition day carbohydrate de-
livery into skeletal muscle. Thus, creatine supplementa-
tion may be a potentially effective tool during peak-week
for acutely expanding muscle size. However, it should be
noted that not all individuals will respond to exogenous
creatine intake vis-à-vis significantly increasing muscle
creatine content [135,136]. In particular, “responders”
tend to be those who have a larger type II muscle fiber
area (i.e., those with an innate proclivity for sprinting
and/or strength/power sports) [137,138] and/or those
with lower initial creatine levels, perhaps due to lack of
intake (e.g., those who have not been supplementing
with creatine or who are non-supplementing vegetar-
ians) [139].
Omega-3 fatty acid [eicosapentaenoic acid (EPA), doc-
osahexaenoic acid (DHA)] supplementation has also
been observed in bodybuilders [2,3]. Chappell et al. re-
ported that 39 % of males and 47 % of females consumed
an omega-3 supplement (e.g. fish, krill, flax-oil) [2]. Al-
though substantial data in many population demograph-
ics supports the use of EPA & DHA as a means to
reduce systemic inflammation and improve insulin sensi-
tivity [140,141], it remains unknown if this can enhance
the peaking process.
As discussed previously, the use of diuretics has been
commonly reported in the competitive bodybuilding
space [8,19–21,34,35]. Bodybuilders often use diuretics
(both herbal and synthetic drugs) to increase urine out-
put and excrete sodium in an effort to alter fluid volume,
enhance body composition, and present a more aesthetic
physique [142]. Moreover, some may use diuretics to re-
duce total body mass with the aim to make a specific
weight class [8,19–21,34,35,143]. For example, Cald-
well et al. [143] investigated the effects of a prescription
diuretic (furosemide 1.7 mg/kg) on athletes of various
sports (e.g., weightlifters and martial artists) and re-
ported a significant reduction in total body mass (-3.1 ±
0.8 kg) over a 24-hour period. However, due to the po-
tential health dangers and their ability to mask the use
of performance enhancing drugs, prescription diuretics
have been banned by the World Anti-Doping Agency
[144]. While these drugs are presumably not used by
natural bodybuilders, they have been employed by en-
hanced non-tested competitors [19,20]. Interestingly,
some herbal supplements that are not banned have dem-
onstrated a diuretic effect and may be employed by en-
hanced and natural bodybuilders alike. For example,
taraxacum officinale (dandelion) has been shown to sig-
nificantly increase urine frequency and excretion output
in an acute fashion (i.e. within a 10 h window) [145];
however, to our knowledge, no research has directly ex-
amined its impact on intracellular vs. extracellular fluid
shifts or on its effectiveness during peak week.
Vitamin C (ascorbic acid) is water-soluble and consid-
ered non-toxic even in high amounts [146]. Since it re-
quires renal filtration for excretion, it also brings about
osmotic diuresis [147]. Research supports a diuretic ef-
fect of both oral and IV vitamin C [148], with daily doses
as low as 11 mg/kg producing diuresis in children [149],
although a 500 mg IV dose failed to induce diuresis in
adult males [150]. A study of both healthy subjects and
vitamin C deficient patients demonstrated that urinary
Vitamin C losses (and accompanying diuresis) occurs
only above threshold blood concentrations of ~ 14 mg/L
(which corresponds to tissue saturation levels). These
data suggest that reaching diuresis-promoting vitamin C
blood concentrations varies as a function of rates of ab-
sorption and uptake/deposition into tissues [151] (3).
Given its common usage, relative safety, and potential
effectiveness as a non-pharmacologic diuretic, the use of
ascorbic acid in a peak week scenario (including dosing
patterns to minimize GI distress and optimize blood
concentrations in the context of meal timing and other
factors that may influence absorption) warrants of fur-
ther research. Indeed, due to the paucity of research
available on the subject, it is difficult to make definitive
recommendations on usage and dosage during peak
week. However, based on the evidence available,
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repeated dosing (every few hours) of 500–1000 mg of
vitamin C is a viable strategy to be utilized during the
12–24 h before competitive stage appearance to poten-
tially accelerate body water loss with minimal side effects
(e.g., gastrointestinal distress). Please note that caution is
warranted as excessive vitamin C consumption may
cause osmotic diarrhea [152].
Caffeine use is another supplement of special mention
due to its diuretic properties. Doses of at least ~ 250-
300 mg caffeine (2–3 cups of coffee) can be taken to
promote diuresis acutely in those who are not caffeine-
tolerant due to chronic use [153]. On the other hand,
several days of abstinence can restore sensitivity to caf-
feine’s diuretic effects (although the diuretic effect is still
only present at these larger doses) [154]. Caffeine’s diur-
etic, mood-improving [155] and performance enhancing
effects [156] should also be considered in the context of
potential sleep disturbances if taken acutely to promote
diuresis to make weight and/or the night before compe-
tition, as well as withdrawal effect if use is abruptly dis-
continued [157]. One potential peak week strategy
would be to limit caffeine early in the peak week process
(especially in chronic users, to restore sensitivity), em-
ploy it early in the day as a diuretic (e.g., on the day be-
fore competition) to limit adverse effects on sleep
quality, and continue its use thereafter (e.g., upon rising
the day of competition) to prevent withdrawal effects on
both fluid homeostasis and/or mood and arousal [157].
It has been noted that caffeine can be employed (3-
8 mg/kg) as an agent to speed glycogen loading [158], al-
though data are sparse and equivocal as to this effect
[159]. Thus, athletes who might choose to include caf-
feine to enhance carbohydrate loading in the middle of
the peak week may potentially also be forfeiting its use-
fulness as a diuretic during the days thereafter (i.e., when
“drying out”the ~ 24 h before stepping on stage).
Fiber and FODMAPs
Dietary fiber is indigestible plant matter of carbohydrate
sources that can be categorized as water-soluble or in-
soluble (i.e. fermentable) and plays a vital role in gastro-
intestinal health and bowel-movement regularity [160].
Bodybuilders who are aiming to reduce total body mass
during peak week as a means to make a particular
weight class may benefit by intentionally reducing fiber
intake. For example, Reale et al. [55] investigated the ef-
fect of dietary manipulations (i.e. macronutrient, fiber,
sodium, and water intake) on acute weight loss for com-
bat athletes and prescribed 10-13 g of fiber to reduce
total gut content and body mass. Different food sources
impact fecal bulking characteristics and those high in
fiber tend to increase water in the interstitial space and
stool bulk [161]. Data have shown a direct relationship
between fiber intake and bowel contents with acute
restriction periods (as short as two days) to be effective
at emptying/clearing the gastrointestinal tract [162].
Thus, the rationale to reduce fiber intake before the
competition is typically to minimize the risk of bloating/
water retention [11], and for some, may be an effective
strategy for making a weight class.
Although research is limited on the topic, Chappell
et al. [11] reported that the bodybuilders they observed
severely reduced their fiber intake primarily by redu-
cing/omitting fibrous vegetables during peak week.
Additionally, it is well understood that fermented oligo-
saccharides, disaccharides, monosaccharides, and polyols
(FODMAPs) are poorly absorbed, draw fluid within the
GI tract, and increase the likelihood of bloating/gas
[163]. Thus, it may be advisable for bodybuilders to limit
high FODMAP food sources during peak week. This
may be one reason why dairy/lactose and gluten rich
food sources are also anecdotally restricted in this period
as well. On the other hand, fiber sources such as guar
gum [164] and psyllium [165], which have been shown
to reduce symptoms of irritable bowel syndrome domi-
nated by both constipation and diarrhea, might be
employed on an individual basis to offset gastrointestinal
distress, as noted above in the study by de Moraes et al.
[15]. Despite the lack of data within this demographic,
dietary fiber is likely a variable that can impact a body-
builder’s peaking process and should be considered on
an individual basis in context with the other aspects of
the peak week approach.
Training
Since bodybuilders invariably train primarily with resist-
ance exercise (RE), the extent to which RE in particular
reduces glycogen and IMT warrants consideration. In an
early study of fuel use during RE in trained bodybuilders,
Essen-Gustavsson and Tesch [96] found that a high vol-
ume, lower body RE session reduced both vastus lateralis
glycogen and IMT by ~ 30 %, and that both resting levels
and the extent of depletion correlated to the
energetically-related enzymes hexokinase and 3-
hydroxy-Co-A dehydrogenase, respectively. In another
study, just three sets of arm curls (80 % 1RM or ~
12RM) was enough to reduce biceps brachii glycogen by
24 % and elevate muscle lactate ~ 20 fold in trained
bodybuilders [166]. Similarly, Robergs et al. [167] found
that 6 sets of knee extensions (~ 13 reps/set; 2 min rest
intervals) reduced muscle glycogen by approximately
40 % in resistance trained males, but glycogen levels re-
covered 50 % of losses during 2 h of fasting rest, presum-
ably due to the immediate post-exercise assimilation of
glycogenolytic metabolites (e.g., lactate) [168]. The same
group also found that an external workload-matched re-
gime (employing double the load such that sets averaged
only ~ 6 reps to failure) produced a nearly identical
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pattern of glycogen use and immediate post-exercise re-
covery. Thus, RE performed with commonly employed
rep ranges among bodybuilders substantially reduces
muscle glycogen stores in a manner related to the work-
load/volume of a given bout.
In line with previous research suggesting that fat oxi-
dation is greater in females as well as those with higher
body fat levels [85,169], a study of untrained obese
women found that 42 % of resting mixed muscle IMT
stores were used during only 6 sets of 10 repetitions of
knee extension [170]. While IMT had returned to 33 %
below baseline 2 h after exercise despite no intake of
food, muscle glycogen stores diminished by only 25 %
over the course of the bout but failed to significantly re-
cover in the absence of food consumption [170]. The
above data suggest that IMT restoration may proceed
slowly in lieu of dietary sources [171], whereas CHO is
required to substantially restore glycogen levels beyond
an acute post resistance training re-sequestration of
glycolytic intermediates.
Thus, the potential to modify intramuscular glycogen
and IMT stores via diet (see above) and exercise is clear,
but the corresponding effects may be variable across
bodybuilders as a function of pre-contest diet (macronu-
trient composition and content may affect resting
stores), muscle enzyme activity, and gender, among
other uninvestigated variables. Exercise-induced muscle
damage may also be important in interpreting the above
data since it is highly variable [172–174], a function of
training status [175], and known to impair muscle insu-
lin sensitivity [176] as well as glycogen replenishment
[177]. Avoiding excessive muscle damage may thus be
important when considering a resistance training strat-
egy during peak week not only to maximize glycogen
and IMT stores, but also to prevent unwanted delayed
onset muscle soreness that may impede the ability to ac-
tivate muscles [178] during posing. In fact, the energetic
demands of recovery from a damaging bout may be so
great in extreme cases that glycogen levels can continue
to decrease post-exercise and not fully recover in 24 h
despite high CHO consumption (10 g/kg/day) [179].
Variability in the extent of post-exercise inflammation
[180,181] may also explain the above-noted variability
in the extent of hydration that accompanies glycogen
loading. Resting IMT and glycogen levels are higher and
used more readily in trained subjects who employ
greater absolute workload. However, post-exercise res-
toration of both fuel sources correlates with insulin sen-
sitivity and proceeds similarly relative to resting stores
regardless of training status [182]. Thus, the high insulin
sensitivity generally observed in pre-contest body-
builders [5,7,90,183,184] confers an advantage for
IMT and glycogen restoration after high substrate-
demanding training sessions [185], but their greater
muscle mass and capacity to reduce muscle fuel stores
dictate that dietary fat and CHO intake must be com-
mensurately large to ensure a super compensatory effect.
Practical Applications for Peak Week
It is evident that bodybuilders implement a variety of
peak week strategies despite the paucity of bodybuilder-
specific research on safety and efficacy. Since there are
many interrelated variables to consider during the peak-
ing process that directly influence each other, specific
peak week recommendations are not possible. Further-
more, there are significant inter-individual responses to
the manipulation of these variables and bodybuilders
may have to take different approaches during peak week
depending on their circumstances, goals, and how their
body responds to the alterations of the variables. For ex-
ample, peak week approaches could differ substantially
based on their circumstances of a bodybuilder that needs
to make a weight for a specific weight class as compared
to a bodybuilder that is not bound by a weight limit.
Similarly, different approaches might need to be imple-
mented by athletes competing in the various subdivi-
sions of bodybuilding (i.e., women’s physique/figure/
wellness/bikini/fitness and men’s physique/classic phys-
ique) where judging standards may differ from those of
traditional bodybuilding.
While an in-depth discussion of the nuanced and
somewhat fluid judging standards (which vary across the
numerous bodybuilding federations/organization) of the
various competitive physique divisions is beyond the
scope of this review, the following general considerations
can be applied in constructing a peak week strategy for
these other divisions: (1) The standard for leanness in
the non-bodybuilding women’s divisions often call for
higher body fat levels and less muscularity than women’s
bodybuilding, and may also thus require few or none of
the peak week manipulations described here; (2) Anec-
dotally, female competitors (typically in Bikini or Figure
divisions) may intentionally reduce total body fat to ob-
tain competitive lower body fat levels and, rather than
applying diuretic procedures, will “water load”in an at-
tempt to reduce the appearance of excessive leanness
but retain the desired appearance of more evenly distrib-
uted body fat distribution, and; (3) Fitness competitors,
where physical performance as well as physique appear-
ance are judged, may have to create highly individualized
approaches to water and fuel restoration that optimize
competitiveness, minimize injury risk, and account for
the relative timing of routine and physique rounds over
the course of a competition.
Given the current evidence discussed within the body
of the manuscript, we offer the following general recom-
mendations for bodybuilders to help readers develop in-
dividualized peak week strategies that coordinate
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macronutrient intake, hydration and electrolyte strategies,
supplementation, and resistance/endurance exercise regi-
mens. It is important to emphasize that these recommen-
dations should not be considered concrete “rules”as there
is significant individual variability of how athletes may re-
spond to the manipulation of these variables. Indeed, due
to the number of variables that may be manipulated and
the virtually endless scenarios that may occur, we present
more specific peaking guidelines for: (1) A women’sphys-
ique competitor (60 kg that is not bound by a weight limit
(BB1); (2) a superheavyweight (105 kg) bodybuilder that is
not bound by a weight limit (BB2); (3) a classic physique
competitor that needs to be under a weight limit (85 kg)
based on his height class (BB3). In all circumstances, it will
be assumed that competitors check-in (and weigh-in if ap-
plicable) on Friday afternoon to compete on Saturday
morning for prejudging and Saturday evening for finals.
Please note that despite these specific circumstances, the
recommendations presented in Fig. 1and Tables 1,2,and
3should be seen as recommended starting points that will
likely require adjustments based on the individual’sre-
sponses to the alteration of the variables. The mock peak
week strategy in the Fig. 1 are presented only as illustrative
examples and should not be considered prescriptive diet-
ary, exercise and/or medical advice. Please refer to the text
for a detailed rationale for the macronutrient, water, so-
dium and potassium manipulation presented in Fig. 1and
Tables 1,2and 3. To these ends, peak week strategies
would include the following considerations:
1) During a depletion/supercompensation resistance
exercise protocol, resistance exercise should engage
all major muscle groups and employ a variety of
exercises to ensure widespread reduction in IMT
and glycogen levels across the entire muscle mass.
2) Using a relatively high repetition scheme (> 12
repetitions) with either a lower or higher volume
approach [167], and exerting enough effort and/or
load to engage most fiber types [186–188]but
stopping short of failure and employing a training
volume/intensity taper while avoiding novel exercises
seems prudent to ensure muscle damage is minimized.
3) Exercises that overload the muscle in their
lengthened range/are eccentric dominant (e.g.
Romanian Deadlift, DB Lat Pullover, DB Fly) should
be minimized since training at lengthened positions
has been shown to increase muscle damage [189].
4) Cardiovascular exercise should be tapered and
preferentially eliminated before attempting to super
compensate fuel stores dietarily in the days
preceding competition.
5) Resistance training during peak week should
generally take place early in the week, spread out
over 3–4 days depending on the athlete’s
accustomed training split, to allow adequate time
for supercompensation during the days before
stepping on the competition platform. Training legs
first in this series of peak week workouts allows the
greatest time for recovery in these muscle groups.
6) The potential for glycogen loading to impair IMT
storage suggests that separating periods of glycogen
and fat loading may be prudent, with a high CHO diet
preceding efforts to fat load [92]. Reducing fat
coingestion with large amounts of carbohydrate may
also avoid negative effects of free-fatty acids on glyco-
gen formation [190], reduce gastric distension by
speeding gastric emptying, as well as improve glycogen
loading by further elevating blood glucose and insulin
levels [191–193]. When consumed on different days,
diets containing fat at 2 g/kg/day [92]andCHOat
10 g/ kg/day [100] can restore and potentially super-
compensate their respective fuel depots within 24 h.
Individual variability and athlete goals/needs may re-
quire different strategies, including allowing > 24 h for
glycogen loading [194]ifcircumstancespermit.
7) Rather than introducing new foods, consuming
mainly the same dietary constituents during peak
week as those consumed during the preceding
weeks/months beforehand may also be helpful in
avoiding gastric distress. Since fruit and fructose
sources of carbohydrates better stimulate liver
glycogen restoration, whereas glucose does so for
muscle glycogen [195], it is recommended that the
majority of the carbohydrates consumed come from
starchy/glucose-based sources. Of note, however, is
that combinations of glucose, fructose, and sucrose
with sports drinks have been shown to enhance the
rate of fluid absorption from the proximal small
intestine [196]. Thus, it is recommended that
athletes experiment prior to peak week as to what
carbohydrate sources work best for them.
8) Ensuring protein is co-ingested, albeit in perhaps
lower quantities, with CHO may increase insulin re-
lease and facilitate glycogen loading [197,198].
9) A higher protein intake (i.e., 3.0 g/kg) may be
combined with a higher fat intake during periods of
CHO depletion to initiate fat loading followed by
CHO loading with a lower protein intake (i.e., 1.6 g/
kg) to super compensate glycogen stores. Once
carbohydrate loading is complete, a higher protein
(3.0 g/kg)/high fat/lower CHO diet may be
implemented. Once again, individual variability and
athlete goals/needs may require different strategies
to peak the physique.
10) Various CHO loading strategies have been reported
in bodybuilding. For example, Roberts et al. [199]
discuss the practice of front-loading CHO (intake is
higher earlier in the week and then lowered to
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maintain muscle fullness leading to the competi-
tion) and back-loading CHO (intake occurs later in
the week but may result in less time to make adjust-
ments to the physique). Alternatively, a model
whereby CHO is depleted early in the week (7 −4
days out), loaded mid-week (3 −2 days out), and
then adjusted/maintained (1 day out) could also be
utilized. In the study by de Moraes et al. [15], a
back-loading method was used, but more evidence
is required before more concrete recommendations
are made. Based on the current evidence, we rec-
ommend the third model discussed, as presented in
Table 1for the 60 kg female physique competitor
and the 105 kg male bodybuilder, to gain the bene-
fits of front-loading and back-loading; however, in-
dividual responses/preferences to CHO loading and
the individual’s needs (i.e., making a weight class
may require back-loading) must all be considered.
11) The preceding pre-contest diet may affect competi-
tor tolerance to dietary manipulation, as well the
extent of dietary restriction of fat and CHO during
peak week training days needed to precipitate a sub-
sequent super-compensatory effect. For instance,
those competitors following a high CHO/low fat,
but very low calorie diet (leaving glycogen levels
chronically low) might best avoid completely elim-
inating CHO during peak week training. However,
those who have been using a low carbohydrate ap-
proach could continue employing a low CHO diet
during peak week but might be wary of excessive
training (tapering instead approach) if glycogen
levels are likely diminished at the start of peak
week.
12) Generally speaking, lowering CHO and raising fat
intake (as tolerable) during the peak week training
(“depletion”) days may facilitate glycogen loading
during the days after training, and simultaneously
ensure IMT levels are not lowered excessively. After
1–2 days of glycogen loading mid/late week as
recommended in our CHO loading approach, IMT
levels could then be elevated the day before
competition with a high fat/low CHO approach
that would also serve to reduce body water [117].
Once again, individual variability and athlete goals/
needs may require different strategies with these
general guidelines.
13) The practice of water loading followed by water
restriction has been documented to be a safe and
effective weight loss strategy to lose TBW in
combat athletes [55]. While the ratio of ECW to
ICW lost was not reported in this study, Costill
et al. [40] (as previously stated) reported that the
ratio of ECW to ICW loss stays close to 1:1 when
glycogen levels stabilize over time and higher levels
of dehydration are reached. Thus, it seems that
retention of muscle glycogen, by avoiding exercise
that relies heavily on glycogen, may be important if
methods of water loss are to effect a favorable loss
of ECW relative to ICW (ECW > ICW) such that
muscle size is retained while interstitial ECW is
preferentially lost, potentially enhancing the
appearance of muscle “definition.”
14) Many variables may alter the approach used to
water load/water deplete (i.e., how much water the
athlete is accustomed to drinking on a regular
basis), but the participants in the Reale et al. study
successfully lost TBW by drinking a large quantity
of water (100 ml/kg) for three days followed by
significantly cutting water to 15 ml/kg on the
fourth day [55] with no deleterious effects.
Alternatively, water intake can be kept relatively
constant (with the exception of a few hours before
competing to prevent any abdominal distention) to
minimize the variables being manipulated; indeed,
this might be the best approach if no practice runs
are performed prior to competing.
15) Since muscle glycogen creates an osmotic effect,
pulling water into the cell as glycogen is stored [26],
CHO loading should be carried out in conjunction
with water intake [199] so that muscle ICW can be
maximized while CHO intake is high. After
approximately three days of water loading with a
higher CHO intake (if the water loading method is
used), water intake can decrease to ~ 15 ml/kg for
24 h which will help to induce diuresis within the
~ 24 h prior to the competition. Note that this
recommendation is based on what has been studied
and reported; however, the authors recognize that
higher water intakes may be preferential such as
30–40 ml/kg but have not been investigated and
thus require further research.
16) Increasing or maintaining a high protein intake
while lowering carbohydrate consumption and
concomitantly increasing fat intake during the day
before competing conceivably would reverse
unwanted gains in extracellular/subcutaneous water
experienced during carbohydrate loading [118].
17) Sodium intake has been reported to be significantly
reduced by bodybuilders during peak week [11,14,
20], but the timing of this practice should be
carefully implemented and sodium intake should
not be reduced simultaneously with CHO loading
since evidence suggests that the delivery of CHO is
limited by the transport capacity of SGLT1 [72–75].
Once CHO intake has decreased after glycogen
loading, sodium intake may be temporarily reduced
since research indicates that the RAAS activation is
evident within 24 h and it takes ~ 48 h to observe a
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sharp increase in plasma aldosterone levels [53].
This temporal lag in establishing fluid and
electrolyte homeostasis, if timed correctly, may be
implemented to induce diuresis before the
protective homeostatic mechanisms fully manifest
to halt water loss. Depending on the bodybuilder’s
needs prior to competition (e.g., necessity to make a
weight class), various sodium intake scenarios are
presented in Table 2. Alternatively, sodium can be
kept as a constant to minimize the variables being
manipulated; indeed, this might be the best
approach if no practice runs are performed prior to
competing.
18) Storage and retention of muscle glycogen is highly
dependent on potassium availability (a primary
intracellular cation) [41–46]. Hence, ensuring
adequate potassium intake during both
carbohydrate loading and water cutting procedures
(if implemented) is likely paramount to optimizing
stage appearance via storage and retention of
muscle glycogen and thus encouraging a more
favorable loss of ECW relative to ICW when
employing dehydration strategies.
19) Reducing fiber intake during peak week appears to
offer some potential benefits. Rale et al. [55]
reported that reducing fiber intake to 10-13 g/day
for ~ 5 days successfully reduced total gut content
and body mass in contact fighters. Data have shown
a direct relationship between fiber intake and bowel
contents with acute restriction periods (as short as
two days) to be effective at emptying/clearing the
gastrointestinal tract [162]. Thus, the rationale to
reduce fiber intake before the competition is typic-
ally to minimize the risk of bloating/water retention
[11], and for some, part of their process to make a
weight class.
20) The utilization of some supplements during peak
week may prove to be beneficial to athletes.
Creatine supplementation has been shown to aid
in glycogen synthesis and supercompensation
[132]. Additionally, consuming CHO with
creatine increases creatine loading [133], which
increases intracellular hydration [32,129]. In
conjunction with creatine, carbohydrate powders
(e.g. dextrose, highly-branched cyclic dextrin,
etc.) may also be considered. Carbohydrate char-
acteristics such as osmolality, gastric clearance
rate, and glycemic index are some of the vari-
ables bodybuilders should take into consideration
as these factors can significantly vary between
sources and may impact gastrointestinal symp-
toms (e.g. bloating, cramping, diarrhea, constipa-
tion, etc.) [119–121]. Both hydrolyzed whey
protein powders and carbohydrate powders may
be utilized as means to manipulate and consume
specific macronutrient quantities without having
to consume larger volumes of food.
21) Emotionally stressful situations can evoke polydipsia
and alter fluid homeostasis in as little as 48 h [78,
79]. Hence, psychological stress may counteract the
competitive bodybuilder’s attempts to reduce body
water, especially in extreme cases of pre-
Table 1 .
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competition anxiety. As noted previously, we rec-
ommend performing a practice run of the peak
week strategy ~ 2–4 weeks before the actual compe-
tition, in part to reduce anxiety and assure the com-
petitor that the peak week strategy is both
manageable and effective.
22) Resting and/or sleeping with a “head down tilt”
(HDT) position (typically −4to-6˚whereby the
entire sleeping surface is downsloping [57,58]
simulates the increase in cardiac venous return (and
loss of orthostatic pressure) that occurs during
microgravity and results in diuresis and
cardiovascular responses [57,59]. Thus, competitors
could conceivably employ HDT when resting and
sleeping during the 12-24 h before competition to
further encourage diuresis. This potential benefit
should be balanced with possible detrimental effects
of the practice on sleep patterns, which could inter-
fere with competition performance.
23) Scale weight can be used during peak week to
evaluate and confirm hydration levels (see Practical
Considerations section below).
24) Since there are a multitude of variables involved and
substantial biological inter-individuality, a practice or
“mock”peak week performed during the ~ 2–4weeks
before competition can provide invaluable informa-
tion regarding the appropriate extent and timing of
alterations of diet and training during peak week.
Furthermore, it may attenuate the levels of stress that
a bodybuilder may have prior to competing, which
may facilitate how the body responds to the peak
week process.
25) Athletes who may be partaking in a series of
competitions in relatively rapid succession, typically on
a weekly basis, should construct peak week strategies
(as in our examples here) that can be replicated, with
additional adjustments as needed, during the time
period between competitions. This may require
competitors to maintain strict dietary control and
rapidly establish fluid homeostasis post-competition so
as to restore the baseline starting conditions (e.g.,
muscle glycogen levels) upon which a given peak week
strategy may rely. Further, in addition to the medical
risks noted previously, the ill-advised use of pharmaco-
logical diuretics during peak week may likely disrupt
fluid homeostasis and diminish the reliability and thus
successofdiureticstrategiesemployedoveraseriesof
competitions in close temporal proximity.
Table 2 .
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It is essential to understand that none of the afore-
mentioned peak week strategies will provide a physique
makeover to compensate for a lack of preparation or ad-
herence during the off-season or pre-contest phases of
contest preparation. Body fat should be minimized ~ 2–3
weeks before competition, such that the competitor can
focus on minimizing subcutaneous water to best display
muscularity, and maximizing muscle size by increasing
intramuscular stores of glycogen and triglyceride. Thus,
employing peak week strategies is merely a means to
achieve superior on-stage competition day appearance
by “fine tuning”the body compared to simply maintain-
ing the pre-contest diet and training strategies (i.e., those
focused primarily on reducing body fat and maintaining
or gaining muscle mass) .
Practical Considerations for Day of Competition
Ideally the physique presented on stage represents the
athlete’s best possible appearance, superseding that of
the preceding weeks and months. Ensuring that the peak
occurs on the day of competition often requires a tai-
lored approach with at least the following
considerations:
Competition day schedule: When is the athlete
judged and how many times? Many competitive
organizations include multiple judging rounds [200–
202] and categories such that the competition may
transpire over the course of an entire day (or
longer).
Strategies (pre-planned or otherwise) to fine-tune
the physique’s appearance on competition day by
manipulating water, food, and dietary supplement
intake as needed.
Subjective appearance and perception of the
physique (per the above) and other means of
assessing stage readiness. Of course, the goals of
peak week to minimize subcutaneous water and
ensure IMTG and skeletal muscle glycogen stores
are maximized putting the muscle bellies in full
relief and displaying maximal “muscularity”should
largely be accomplished before waking the day of
competition. In bodybuilding vernacular, these
components of muscularity could be considered
“dryness”(lack of subcutaneous fluid) and “fullness”
(the muscle cell fuel stores are fully repleted / super
compensated). However, some fine tuning is often
necessary to optimize the physique’s appearance
when being judged.
To our knowledge, research examining the extent to
which subjective or other practical means of ensuring
bodybuilding competition day preparedness are associ-
ated with the presumed underlying fluid and histological
measures has not been studied. However, the following
Fig. 1 Peak Week Macronutrient Manipulation and General Overview
Escalante et al. BMC Sports Science, Medicine and Rehabilitation (2021) 13:68 Page 16 of 24
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are commonly accepted and previously suggested [36]
ways of evaluating contest day readiness:
Are the muscle glycogen stores “full,”and can the
athlete get a pump? Glycolytic metabolites (e.g.,
lactate and inorganic phosphate) derived from
glycogen use produce a post-exercise reactive
hyperemia response known as a “pump”[203] that
swells muscle tissue, increasing thickness as much as
~10% [204,205]. This poses an advantage for
acutely increasing muscle size before stepping on
stage and shifting fluid into specific muscle bellies
(ideally even thereby reducing interstitial subcutane-
ous fluid volume to further enhance the appearance
of muscularity), such than an athlete can preferen-
tially “pump up”the musculature to improve the
balance of the muscular development.
Is the athlete “dry?”Has body water been reduced
enough to minimize subcutaneous fluid to
noticeably highlight the underlying musculature?
Is the athlete “flat?”Creating a situation of muscle
fullness and physique dryness requires a tight
physiological balancing act. The hyperemic “pump”
requires adequate body fluid to move into the
muscle belly; however, an athlete with high muscle
glycogen levels but excessively reduced body water
may experience “flatness,”i.e., a lack of a muscle
pump usually associated with a withered appearance
due to excessive dehydration. On the other hand,
lack of muscle glycogen to serve as the source for
metabolic osmolytes for the pump effect [203] could
also be to blame.
Both glycogen stores (“fullness”) and dehydration
(“dryness”) are dependent upon rapidly changing fluid
homeostasis. Thus, we propose that scale weight may be
employed as a rudimentary, but practical and objective
marker of body hydration (“dryness”) in the context of
the muscle pump and visual appearance, as well as the
urinary fluid losses [note that urine color is an adequate
field measure of hydrate state, but may be altered by
dietary supplement consumption [206,207]. Thus, meas-
uring body weight throughout peak week and its rate of
change can help determine the extent to which body
water has been minimized on the day of competition.
Measurements for a hypothetical competitor are given in
Table 4. We assume here that skeletal muscle glycogen
has been adequately super compensated (increasing
intramyocellular water content and raising body weight)
after a period of reduced carbohydrate intake that re-
duces body water content (and body weight) early in
peak week (see above). If dehydration strategies result in
a reduction scale weight that approximates or is below
pre-carbohydrate loading levels, we hypothesize this re-
flects that the desired changes in the ECF (reduced
subcutaneous fluid) and ICF spaces (increased intramyo-
cellular fluid and glycogen) has been achieved.
Figure 2below outlines a competition day decision-
making tree a competitor could employ to address the
possibilities discussed above (lack of muscle fullness or
physique dryness, or being “flat”). We presume a prefer-
ence on minimizing body water over muscle fullness.
Also, note that the scenario where “flatness”is an issue
could require some combination of adding water, so-
dium, carbohydrate and/or dietary fat depending upon
the circumstances. Previous mock peak week and carb-
up experiences may serve the athlete well here in choos-
ing an appropriate day of the show strategy. This same
decision-making tree can be applied repeatedly in situa-
tions where the athlete is judged in multiple rounds.
Table 3 Supplement Considerations During Peak Week
Supplement Notes on Strategic Supplement Use during Peak Week
Creatine Creatine (Cr) supplementation has been shown to increase intracellular fluid volume by ~ 3 % without impacting ECF and up
to 6.6 % for total muscle volume [131]. Additionally, it has been shown to aid in glycogen synthesis and super-compensation
[31,129]. Although it’s advisable for physique athletes to supplement with Cr for the entire contest preparation, continuing to
supplement throughout peak week is suggested. If an athlete has supplemented with creatine throughout the contest prepar-
ation, a ‘maintenance’dose of 0.03 g/kg/day may be employed. If the athlete has not regularly used Cr throughout the contest
preparation, supplementation during peak week would require a ‘loading’0.3 g/kg/day. This would translate to 25 g/day dur-
ing a loading phase and 5 g/day for maintenance when using a 180lb (82 kg) subject as an example.
Carbohydrate
Powders
During the carbohydrate loading process with the intent of super-compensating muscle glycogen, carbohydrate supplements
may be beneficial to reduce this risk of negative gastrointestinal symptoms (e.g. bloating). With carbohydrate intakes poten-
tially reaching 10-12 g/kg, the sheer food volume alone can be problematic. Some carbohydrate supplements (e.g. highly
branched cyclic dextrin) may be favorable due to their osmolality and gastric clearance rate. This may particularly advanta-
geous for physique athletes who had to deplete and dehydrate to make weight for their class and have a small time window
to carbohydrate load.
Herbal Diuretics Herbal diuretics (e.g. dandelion root) may be employed in an acute fashion to increase urine frequency and excretion output
[149]. The potassium rich herbs may further enhance the dehydration process, specifically by expelling extracellular water [150,
151]. As noted in the text, caffeine is also an effective diuretic in non-habituated users [152], but runs the risk of causing sleep
disturbance.
Escalante et al. BMC Sports Science, Medicine and Rehabilitation (2021) 13:68 Page 17 of 24
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Conclusions
Evidence suggests that bodybuilders frequently use “peak
week”strategies such as CHO loading, water/sodium
manipulation, and other approaches in an attempt to en-
hance their physique during their last week of competi-
tion preparation. Unfortunately, there is a paucity of
research on the effectiveness and safety of these strat-
egies when implemented individually or collectively.
Since the variables that are frequently manipulated by
bodybuilders are interrelated, the alteration of one vari-
able typically influences other variables. Furthermore,
the inter-individual responses to the alteration of these
variables makes it even more difficult to provide precise
peak week “rules”to follow. Given the complicated
interplay of physiological variables during peak week, as
well as biological inter-individuality and variability in the
importance placed on maximizing various aspects of
muscularity across the different competitive divisions,
there are a multitude of research avenues for investigat-
ing peak week strategies. In particular, tightly controlled
Table 4 Example of Weight Change during Peak Week and Insights
Body
Weight
(BW in
lbs)
Note Insight
Sunday (Start of Peak Week) 202 End of diet before peak week
Wednesday AM (Pre-Glycogen
Loading)
200 After 2–3 days of lower carbohydrate intake
Friday AM (Post-Glycogen Loading) 205 After higher carbohydrate intake Weight gain suggests glycogen super
compensation
Saturday AM (Competition Day) S
C
E
N
A
R
I
O
S
202 Clear urination and BW consistently falling Further dehydration may improve appearance
200 Minimal and darker urination with BW
slowing
Water loss has been effective
198 Urination ceased and BW constant Very likely dehydrated, beware of being “flat”
Fig. 2 Decision Making Tree for Bodybuilding Competition Day Dietary and Fluid Adjustments
Escalante et al. BMC Sports Science, Medicine and Rehabilitation (2021) 13:68 Page 18 of 24
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examination of the quantifiable effects of glycogen
supercompensation, graded dehydration via manipula-
tion of sodium and/or water and pre-stage pump up
strategies, coupled with documentation of the associated
“practical,”subjective visual changes in physical appear-
ance, would be relevant areas of study that may help bet-
ter inform competitors and redirect them away from
potentially dangerous and/or less effective peak week
practices. Thus, the authors present this review and
evidence-based approach to pre-contest peaking strat-
egies based on the current state of the scientific litera-
ture in the hope it may spark further research,
understanding and development of practical, safe ap-
proaches competitive bodybuilders can apply to optimize
on-stage appearance.
Abbreviations
ADH: Anti-diuretic hormone; PRN: As needed; ANF: Atrial natriuretic factor;
HCO3
-
: Bicarbonate; Cl
-
: Chloride; CHO: Dietary carbohydrate; FAT: Dietary fat;
PRO: Dietary protein; DHA: Docosahexaenoic acid; EPA: Eicosapentaenoic
acid; ECG: Electrocardiogram; ECW: Extracellular water; FFM: Fat-free mass;
FODMAPs: Fermented oligosaccharides, disaccharides, monosaccharides, and
polyols; HDT: Head down tilt; IAAO: Indicator amino acid oxidation;
ICF: Intracellular fluid; ICW: Intracellular water; IMT: Intramuscular triglycerides;
JGA: Juxtaglomerular apparatus; MBIA: Multi-frequency bioelectrical
impedance analysis; PO
4-
: Phosphate; K
+
: Potassium; RDA: Recommended
dietary allowance; RAAS: Renin-angiotensin-aldosterone system;
RE: Resistance exercise; Na
+
: Sodium; SGLTs: Sodium-glucose dependent
cotransporters; TBO: Total body osmolarity; TBW: Total body water
Acknowledgements
N/A.
Authors' contributions
GE, SWS, CB, AAA and BJS contributed equally to the writing and revision of
the manuscript. All authors have read and approved the final manuscript.
Funding
N/A.
Availability of data and materials
N/A.
Declarations
Ethics approval and consent to participate
N/A.
Consent for publication
N/A.
Competing interests
BJS formerly served on the scientific advisory board for Dymatize Nutrition,
a manufacturer of sports supplements. GE serves as a scientific consultant for
VPX Sports Nutrition, a manufacturer of sports supplements. The other
authors declare no competing interests.
Author details
1
Department of Kinesiology, California State University- San Bernardino, CA,
San Bernardino, USA.
2
Integrative Bodybuilding LLC, FL, Tampa, USA.
3
Competitive Breed LLC, FL, Tampa, USA.
4
Human Performance Laboratory,
The University of Tampa, FL, Tampa, USA.
5
Department of Family and
Consumer Sciences, California State University- Northridge, Los Angeles, CA,
USA.
6
Health Sciences Department, Lehman College, NY, Bronx, USA.
Received: 14 January 2021 Accepted: 2 June 2021
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