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Different Patterns in Muscular Strength and Hypertrophy Adaptations in Untrained Individuals Undergoing Non-Periodized and Periodized Strength Regimens


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This study investigated the effects of non-periodized (NP), traditional periodization (TP) and daily undulating (UP) regimens on muscle strength and hypertrophy in untrained individuals. Thirty-three recreationally active males were randomly divided into four groups: NP: n = 8; TP: n = 9; UP: n = 8 and control group (C): n = 8. Experimental groups underwent a 12-week strength-training program consisting of two sessions per week. Muscle strength and quadriceps cross-sectional area (QCSA) were assessed at baseline, 6-wk (i.e. mid-point) and after 12-wk. All training groups increased squat 1RM from pre to 6-wk mid (NP: 17.02%, TP: 7.7% and UP: 12.9%, p≤0.002) and pre to post 12-wk (NP: 19.5%, TP: 17.9% and UP: 20.4%). TP was the only group that increased squat 1RM from 6-wk mid to 12-wk period (9.4%, p≤0.008). All training groups increased QCSA from pre to 6-wk mid (NP: 5.1%, TP: 4.6% and UP: 5.3%, p≤0.0006) and from pre to post 12-wk (NP: 8.1%, TP: 11.3% and UP: 8.7%). From 6-wk mid to 12-wk period, TP and UP were the only groups that increased QCSA (6.4% and 3.7%, p≤0.02). There were no significant changes for all dependent variables in C group across the time (p≥0.05). In conclusion, our results demonstrated similar training-induced adaptations after 12-wk of NP and periodized regimens. However, our findings suggest that in the latter half of the study (i.e. after the initial 6 weeks), the periodized regimens elicited greater rates of muscular adaptations compared to NP. Strength coaches and practitioners should be aware that periodized regimens might be advantageous at latter stages of training even for untrained individuals.
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Department of Health Science and Human Performance, University of Tampa, Tampa, Florida;
Department of Physical
Education and Sport, Laboratory of Adaptations to Strength Training, University of Sa˜o Paulo, Sa˜o Paulo, Brazil;
Diagnostic S/A, Sa˜o Paulo, Sa˜o Paulo, Brazil; and
Applied Physiology and Nutrition Research Group, Department of
Physical Education and Sport, University of Sa˜o Paulo, Sa˜o Paulo, Brazil
De Souza, EO, Tricoli, V, Rauch, J, Alvarez, MR, Laurentino, G,
Aihara, AY, Cardoso, FN, Roschel, H, and Ugrinowitsch, C.
Different patterns in muscular strength and hypertrophy adapta-
tions in untrained individuals undergoing non-periodized and
periodized strength regimens. JStrengthCondRes32(5):
1238–1244, 2018—This study investigated the effects of nonper-
iodized (NP), traditional periodization (TP), and daily undulating
periodization (UP) regimens on muscle strength and hypertrophy
in untrained individuals. Thirty-three recreationally active males
were randomly divided into 4 groups: NP: n=8;TP:n=9;
UP: n=8,andcontrolgroup(C):n=8.Experimentalgroups
underwent a 12-week strength training program consisting of 2
sessions per week. Muscle strength and quadriceps
cross-sectional area (QCSA) were assessed at baseline, 6 weeks
(i.e., mid-point) and after 12 weeks. All training groups increased
squat 1RM from pre to 6 weeks mid (NP: 17.02%, TP: 7.7%, and
UP: 12.9%, p#0.002) and pre to post 12 weeks (NP: 19.5%,
TP: 17.9%, and UP: 20.4%, p#0.0001). Traditional periodiza-
tion was the only group that increased squat 1RM from 6 weeks
mid to 12-week period (9.4%, p#0.008). All training groups
increased QCSA from pre to 6 weeks mid (NP: 5.1%, TP:
4.6%, and UP: 5.3%, p#0.0006) and from pre to post 12 weeks
(NP: 8.1%, TP: 11.3%, and UP: 8.7%, p#0.0001). From 6
weeks mid to 12-week period, TP and UP were the only groups
that increased QCSA (6.4 and 3.7%, p#0.02). There were no
significant changes for all dependent variables in C group across
the time (p$0.05). In conclusion, our results demonstrated sim-
ilar training-induced adaptations after 12 weeks of NP and perio-
dized regimens. However, our findings suggest that in the latter
half of the study (i.e., after the initial 6 weeks), the periodized
regimens elicited greater rates ofmuscularadaptationscompared
with NP regimens. Strength coaches and practitioners should be
aware that periodized regimens might be advantageous at latter
stages of training even for untrained individuals.
KEY WORDS periodization, strength training, muscle cross-
sectional area
Strength training (ST) is widely used to increase
muscular strength and mass (i.e., hypertrophy)
across different populations (3,6,12,24). In this re-
gard, the systematic manipulation of ST-related
variables (i.e., training periodization) has been advocated
to optimize training-induced adaptations (1).
Although there are several periodization models that can be
used during an ST program, it is possible to pinpoint the 2 most
common ones. Traditional periodization (TP) consists of
increasing intensities and decreasing volumes throughout the
training period, whereas undulating periodization (UP) is
characterized by alternating high-volume low-intensity with
low-volume high-intensity training sessions during training (1).
Several studies have suggested that periodized models
(e.g., TP and UP) optimize strength gains when compared
with nonperiodized (NP) regimens (NP—i.e., constant inten-
sity and volume) (1,14,17,23,29). However, when volume
load was equated, the few studies that have compared perio-
dized and NP models did not report superior strength gains
between training regimens (8,18,22).
Concerning muscle hypertrophy (i.e., increase in cross-
sectional area—cross-sectional area [CSA]), despite a paucity
Address correspondence to Dr. Eduardo O. De Souza,
Journal of Strength and Conditioning Research
!2018 National Strength and Conditioning Association
Journal of Strength and Conditioning Research
Copyright © National Strength and Conditioning Association Unauthorized reproduction of this article is prohibited.
of data on the effects of different periodization and NP regi-
mens on muscle mass accrual, the alleged benefits of periodized
training on muscle hypertrophy have been recently challenged
(8,15,16,21,22,26). In fact, only De Souza et al. (2014) investi-
gated the effects of TP and UP schemes compared with NP
using a gold standard assessment to detect changes on muscle
CSA. The authors found similar improvements on muscle
hypertrophy (;4.96%) between groups after 6 weeks of volume
load–equated protocols (22). However, the short time frame of
the training protocol does not allow further conclusions to be
drawn on how NP and periodized regimens modulate muscle
hypertrophy in untrained individuals over longer periods of
Therefore, the purpose of this study was to investigate the
effects of NP, TP, and UP training regimens on muscle
strength and hypertrophy in recreationally active male
college students. We hypothesized that the ST-induced
adaptations would demonstrate a similar pattern between
experimental groups.
Experimental Approach to the Problem
This was a randomized, parallel-group repeated-measures
design, which investigated the effects of 3 different ST
regimens (NP, TP, and UP) on maximum strength adapta-
tions and quadriceps cross-sectional area (QCSA) in recrea-
tionally active male college students. All experimental groups
trained 2 times a week for 12 weeks. The total number of sets
and repetitions was equated between groups, whereas training
intensity was manipulated differently across training groups
throughout the experimental period. Maximum strength and
QCSA were assessed at baseline (pre), after 6 weeks (6 weeks),
and after 12 weeks (12 weeks) of training by means of back
squat 1RM and magnetic resonance imaging (MRI) of the
quadriceps muscle, respectively.
Forty-one recreationally active male college students (age
range: 19 to 33 years) engaged in sports such as soccer,
volleyball, and basketball, but not undergoing regular
strength and endurance training for at least 6 months before
the experimental period volunteered for this study. Partic-
ipants were stratified based on their pretest QCSA (e.g., CSA
]). Afterward, participants were randomly assigned to
the experimental groups. Participants were free from health
problems and/or neuromuscular disorders that could affect
their ability to complete the training protocols. In addition,
they were instructed to maintain their normal diet, refrain
from taking any nutritional supplements, and endure exer-
cise throughout the study period. After the initiation of the
experimental protocol, 8 participants withdrew because of
personal reasons (Table 1), thus data from 33 subjects were
included in the statistical analysis. All participants were
informed of the inherent risks and benefits before signing
a written informed consent form. The current study was
approved by the School of Physical Education Review Board
of University of Sa
˜o Paulo. Table 1 shows participants’ main
Familiarization Sessions. All participants completed 3 famil-
iarization sessions interspersed by a minimum of 72 hours
before the commencement of the study. During the famil-
iarization sessions, participants performed a general warm-
up consisting of 5 minutes of running at 9 km$h
a treadmill (Movement Technology, Brudden, Sa
˜o Paulo,
Brazil) followed by 3 minutes of whole-body light stretch-
ing exercises. After warm-up, participants were familiarized
with the back squat exercise 1RM testing protocol. Individ-
uals were considered acquainted to the 1RM test if the
coefficient of variation (CV) between familiarization ses-
sions 2 and 3 was lower than 5%. Body position and foot
placement were determined with measuring tapes fixed on
the bar and on the ground, respectively. In addition,
a wooden seat with adjustable heights was placed behind
the subject to keep the bar displacement and knee flexion
angle (;908) constant on each squat repetition. Partici-
pants’ positioning was recorded during the familiarization
TABLE 1. Participants’ characteristics.*
Variable C NP TP UP
Age (yrs) 25.1 63.3 25.6 66.3 25.0 67.0 24.4 65.2
Height (cm) 173.6 66.8 172.8 66.1 175.3 65.7 176.8 65.3
Body mass (kg) 76.8 611.7 79.5 613.0 76.0 69.9 74.9 64.2
1RM (kg) 126.8 621.3 140.7 623.9 141.1 619.7 149.5 634.6
CSA (mm
) 8,913.3 61,041.9 8,801.4 6983.8 8,738.9 6770.8 8,407.6 61,449.0
*C = control group; NP = nonperiodized; TP = traditional periodized; UP = daily undulating periodized; 1RM = one repetition
maximum; CSA = cross-sectional area.
Data are mean 6SD.
Journal of Strength and Conditioning Research
VOLUME 32 | NUMBER 5 | MAY 2018 | 1239
Copyright © National Strength and Conditioning Association Unauthorized reproduction of this article is prohibited.
sessions and reproduced throughout the study. The CV
between familiarization maximum dynamic strength assess-
ments was 3.4%.
Maximum Dynamic Strength Test (1RM). After the familiariza-
tion procedures (i.e., 72 hours after the last familiarization
session), lower limb 1RM was assessed using the back squat
exercise on a conventional Smith machine (Portico; Sa
Brazil). Testing protocol followed previous recommendations
(4). Participants had up to 5 attempts to achieve their 1RM load
(i.e., the maximum weight that could be lifted once with the
proper technique) with a 3-minuteintervalbetweentrials.Each
lift was deemed successful if participants touched their buttocks
on the wooden seat at the end of the eccentric phase and fully
extended their lower limb joints at the end of the concentric
phase of the lift.
Muscle Cross-Sectional Area. Dominant leg QCSA was
obtained through MRI (Signa LX 9.1; GE Healthcare,
Milwaukee, WI, USA). Leg dominance was determined
by asking the participants the preferred leg to kick a ball.
Participants laid on the device in a supine position with
their knees extended. Velcro straps were used to restrain
leg movements during image acquisition. An initial image
was captured to determine the perpendicular distance
from the greater trochanter to the inferior border of the
lateral epicondyle of the femur, which was defined as the
thigh length. Quadriceps cross-sectional area images
were acquired at 50% of the segment length in 0.8-cm
slices for 3 seconds. The pulse sequence was performed
with a view field between 400 and 420 mm, time
repetition of 350 ms, eco time from 9 to 11 ms, 2 signal
acquisitions, and matrix of reconstruction of 256 3256.
The images were transferred to a workstation (Advan-
tage Workstation 4.3; GE Healthcare, Milwaukee, WI,
USA) for QCSA determination. In short, the segment
slice was divided into the following components: skeletal
muscle, subcutaneous fat tissue, bone, and residual
tissue. (Figure 1) Finally, QCSA was assessed by computer-
ized planimetry by a blinded researcher (22). The CV for
QCSA assessments was 1.8%.
TABLE 2. Strength training regimens throughout 12 weeks.*
Wk. 1–4,
1st mesocycle
Wk. 5–8,
2nd mesocycle
Wk. 9–12,
3rd mesocycle Repetitions Rep per day
NP Monday Thursday Monday Thursday Monday Thursday
Back squat 3 38RM 3 38RM 3 38RM 3 38RM 3 38RM 3 38RM
Knee extension 2 38RM 2 38RM 2 38RM 2 38RM 2 38RM 2 38RM 960 40.0
TP Monday Thursday Monday Thursday Monday Thursday
Back squat 3 312RM 2 312RM 4 38RM 4 38RM 3 34RM 3 34RM
Knee extension 2 312RM 2 312RM 2 38RM 2 38RM 2 34RM 2 34RM 976 40.6
UP Monday Thursday Monday Thursday Monday Thursday
Back squat 3 312RM 4 36RM 3 310RM 4 36RM 2 38RM 4 34RM
Knee extension 3 312RM 3 36RM 2 310RM 2 36RM 2 38RM 2 34RM 976 40.6
*NP = Non-periodized; TP = traditional periodization; UP = undulating periodization.
Figure 1. Overview of the traced dominant leg quadriceps cross-sectional area at 3 different time points (pretest, 6, and 12 weeks).
Training Regimens Effects on Muscle Strength and Mass
Journal of Strength and Conditioning Research
Copyright © National Strength and Conditioning Association Unauthorized reproduction of this article is prohibited.
Strength Training Regimens. The participants underwent
a 12-week hypertrophy-oriented lower limb strength train-
ing regimen. Participants trained 2 days per week with
72 hours between training sessions. Strength training
intensity was 4–12 RM (to failure) for both back squat
(conventional Smith machine; Portico", Sa
˜o Paulo, Brazil)
and knee extension (pin-loaded weight machine; Portico",
˜o Paulo, Brazil) exercises. A 2-minute rest interval was
allowed between sets, whereas 3 minutes were respected
between exercises throughout the entire study. All exercises
were performed with constant speed (2-second eccentric
and 2-second concentric muscle actions) and a 908range
of motion at the knee joint. The mesocycles and ST regi-
mens adopted for each of the 3 experimental groups are
presented in Table 2.
Statistical Analyses
After normality (i.e., Shapiro-Wilk) and variance assur-
ance (i.e., Levene), a mixed model was performed for each
dependent variable (volume load, maximum strength, and
quadriceps CSA) assuming group (NP, TP, UP, and C)
and time (pre and post) as fixed factors and participants as
a random factor. Volume load was analyzed assuming
group (NP, TP, and UP) and time (first, second, and third
mesocycles) as fixed factors and participants as a random
factor (SAS 9.4; SAS Institute, Inc., Cary, NC, USA).
Whenever a significant F-value was obtained, a post hoc
test with a Tukey adjustment was performed for multiple
comparison purposes (25). In addition, mean difference
and 95% confidence intervals of the within-group absolute
difference (CI
) were presented. Within-group effect
sizes (ES) were calculated as follows: mean post- minus
mean pre- divided by the pooled SD of pretest values. The
significance level was previously set at p#0.05. Results
are expressed as mean 6SD.
Volume Load and Training Compliance
No significant differences were observed in overall volume
load between training groups NP: 100,460.1 617 ,1 5 5 . 5 k g ,
TP: 95,642.5 616,340.6 kg, and UP: 102,780.1 618,119.9
kg (Figure 2A). When volume load was analyzed per
mesocycle, there was a significant main effect of time
(p#0.0001); all the experimental groups significantly
decreased volume at the third mesocycle when compared
with the first and second mesocycles (226.10%, 228.49%;
p#0.0003), respectively (Figure 2B). Training compliance
was 95.17% (i.e., 22.8 sessions).
Figure 2. Volume load. A- Total volume load, B-Volume load per mesocycle. *p#0.05 when compared with first mesocycle (main time effect). #p#0.05 when
compared with second mesocycle (main time effect).
TABLE 3. Back squat maximum dynamic strength (1RM, mean 6SD).*
Group (1RM kg) pre (1RM kg) 6-wk (1RM kg) 12-wk ES-pre-6-wk ES-6-wk-12-wk ES-pre-12-wk
Control 126.8 621.30 127.68 621.62 132.05 620.12 0.03 0.14 0.20
NP 140.76 623.9 164.87 631.2170.95 636.850.95 0.19 1.19
TP 141.15 619.57 152.96 631.82166.43 630.29z0.45 0.38 0.99
UP 149.57 634.67 167.35 636.01178.35 636.760.70 0.58 1.13
*ES = within-group effect size; NP = nonperiodized; TP = traditional periodization; UP = undulating periodization.
p#0.05 when compared with pre (within-group comparisons).
zp#0.05 when compared with 6 weeks (within-group comparisons).
Journal of Strength and Conditioning Research
VOLUME 32 | NUMBER 5 | MAY 2018 | 1241
Copyright © National Strength and Conditioning Association Unauthorized reproduction of this article is prohibited.
Maximum Dynamic Strength
No significant between-group differences in maximum
dynamic strength were detected at pretest (p.0.05). There
was a significant group by time interaction (p#0.002) in
which squat 1RM values significantly increased in all train-
ing groups from pre to 6 weeks (NP: 17.0%—CI
: mean 25.1
kg, 13.9–36.2 kg; TP: 7.7%—CI
: mean 11.8 kg, 1.3–22.3 kg;
UP: 12.9%—CI
: mean 17.7, 6.6–28.9 kg) and from pre to 12
weeks (NP: 19.5%—CI
: mean 28.1 kg, 16.9–39.2 kg; TP:
: mean 25.2 kg, 14.7–35.7 kg; UP: 20.4%—CI
mean 28.7, 17.6–39.9 kg). In addition, TP was the only group
that significantly increased squat 1RM from 6 to 12 weeks
: mean 13.4 kg, 2.9–23.9 kg, p= 0.008). How-
ever, there was a strong trend towards significant increase at
the same period for UP group (6.9%—CI
: mean 11.0,
20.141 to 22.1 kg, p= 0.053). There were no significant
differences from 6 to 12 weeks in NP group (1.5%—CI
mean 2.9 kg, 28.1 to 14.1 kg, p#0.79). There were no
significant changes in RM for C group across time (p$
0.05) (Table 3).
Quadriceps Muscle Cross-Sectional Area
No significant between-group differences in QCSA were
detected at pretest (p.0.05). There was a group by time
interaction (p#0.0006). Quadriceps cross-sectional area
increased significantly in all training groups from pre to 6
weeks (NP: 5.1%—CI
: mean 451.3 mm
, 159.1–743.4 mm
TP: 4.6%—CI
: mean 409.8 mm
, 134.4–685.2 mm
; UP:
: mean 414.5 mm
, 122.4–706.6 mm
) and from
pre to 12 weeks (NP: 8.1%—CI
: mean 715.0 mm
, 422.9–
1,007.0 mm
; TP: 11.3%—CI
: mean 991.7 mm
716.2–1,267.0 mm
; UP: 8.7%—CI
: mean 749.9 mm
457.7–1,042.0 mm
). In addition, only TP and UP signifi-
cantly increased QCSA from 6 to 12 weeks (TP: 6.4%—CI
mean 581.9 mm
, 306.5–857.3 mm
; UP: 3.7%—CI
: mean
335.4 mm
, 43.2–627.5 mm
,p#0.02). NP demonstrated
a weak trend toward significant increase in QCSA (2.8%—
: mean 263.8 mm
,228.3 to 555.9 mm
whereas there were no significant changes in C group for
QCSA across time (p$0.05) (Table 4).
The purpose of the current study was to investigate the
effects of different training regimens on muscle strength and
hypertrophy in recreationally active male college students.
Data support the hypothesis of similar ST-induced gains in
muscle strength and mass after 12 weeks of training between
experimental groups. Even though there were no significant
differences between training groups both at 6 and 12 weeks
of training, our within-group analyses suggest that after 6
weeks of an NP regimen, maximum strength improvements
were suboptimal when compared with periodized regimens.
In addition, periodized training programs seem to be more
effective than NP training programs at latter stages of
training, as only these groups presented significant increases
in muscle mass from the 6 to 12 weeks of training.
After 12 weeks of training, similar strength gains (;20%)
were observed between groups. Our data are in agreement
with previous literature demonstrating similar strength im-
provements following NP and periodized training models
in untrained individuals (2,16,24). Interestingly, despite
comparable end points, time course in strength gains was
different across groups. For instance, although not statisti-
cally significant, the NP group seemed to have the greatest
rate of change in 1RM after 6 weeks (17%) compared with
all the other groups (TP = 8%; UP = 12%) (Table 3). How-
ever, NP did not improve 1RM in the last 6 weeks of train-
ing (1.5%, p= 0.79). However, UP demonstrated a strong
trend (6.9%, p= 0.053) and TP significantly increased 1RM
(9.4%, p= 0.008) at the latter phase of the study. Although
it is attractive to suggest that periodized models may add
a benefit to strength gains, the specificity might, at least,
explain our results. For example, the TP was the group that
performed more training sessions at higher intensities dur-
ing the second part of the study (e.g., TP: 4 sessions at 8RM
and 8 sessions at 4RM), whereas UP group performed 2
sessions at 10RM, 2 sessions at 6RM, 4 sessions at 8RM,
and 4 sessions at 4RM. Therefore, TP and UP had more
sessions at higher intensities than NP group, which can
explain why the periodized groups demonstrated better
TABLE 4. Quadriceps muscle cross-sectional area (QCSA, mean 6SD).*
Group (QCSA mm
) pre (QCSA mm
) 6-wk (QCSA mm
) 12-wk ES-pre-6 wk ES-6-wk-12 wk ES-pre-12-wk
Control 8,913.3 61,041.9 8,751.0 61,136.3 9,149.1 61,264.2 20.15 0.34 0.21
NP 8,801.4 6983.8 9,247.1 6972.39,613.5 61,017.00.41 0.32 0.75
TP 8,689.4 6770.8 9,099.2 6892.79,681.1 61,049.4z0.37 0.35 0.91
UP 8,407.2 61,449.0 9,064.0 61,503.29,399.3 61,538.6z0.60 0.57 0.91
*QCSA = quadriceps cross-sectional area; ES = within-group effect size; NP = nonperiodized; TP = traditional periodization; UP =
undulating periodization.
p#0.05 when compared with pre (within-group comparisons).
zp#0.05 when compared with 6 weeks (within-group comparisons).
Training Regimens Effects on Muscle Strength and Mass
Journal of Strength and Conditioning Research
Copyright © National Strength and Conditioning Association Unauthorized reproduction of this article is prohibited.
strength gains at the second half of the study. In addition,
a recent meta-analysis suggested that periodized models
have a small to moderate effect on 1RM compared with
NP models. Importantly, those authors reported that study
length was positively related to 1RM changes in periodized
models (28). In this regard, the second half of our study
partially agrees with the outcomes reported by this recent
meta-analysis, as ES from 6 to 12 weeks suggests a small
advantage for the periodized regimens (Table 3).
Furthermore, 1 benefit of periodization that has been
underrated for untrained individuals is that varying training
stimulus more frequently may enhance recovery and allow
subjects to manage fatigue properly. It is noteworthy men-
tioning that reduction in the overall number of repetitions at
the third mesocycle was only planned for the periodized
groups (i.e., TP and UP), whereas NP kept the total number of
repetitions constant. Despite a greater total number of
repetitions in the third mesocycle (i.e., NP: 320, TP: 160
and UP: 224), NP demonstrated similar reduced volume loads
when compared with TP and UP groups. Although interest-
ing, it is difficult to determine what produced an inability to
sustain volume load during the last mesocycle by the NP
group. One important characteristic of the current study was
that all sets were performed until failure. Although there is no
consensus on the efficacy of training to failure on strength
gains, some studies have suggested that fatigue and training to
failure may not be critical for strength gains in untrained
individuals (7,9). Therefore, our findings suggest that even for
untrained individuals, ST planning is important to reduce
fatigue and maximize strength gains over longer periods of
Regarding muscular hypertrophy, the training groups
exhibited similar increases in QCSA after 12 weeks (e.g.,
NP: 8.1%, TP: 11.3%, and UP: 8.7%). To this point, only 1
study has investigated the short-term effects of periodized
and NP regimens on QCSA, which demonstrated similar
changes between the groups (22). Furthermore, the studies
that have compared the effects of TP and UP on muscle
hypertrophy parameters (i.e., CSA and muscle thickness)
reported no differences between the groups (13,16,21). In
fact, a recent meta-analysis comparing TP and UP demon-
strated that in matched volume load studies there is no evi-
dence supporting that 1 periodized regimen can produce
greater hypertrophic adaptations (10). In addition, a system-
atic review demonstrated an average increase in QCSA of
8.5% after different ST regimens (27). Therefore, from pretest
to 12 weeks, the magnitude of muscular hypertrophy re-
ported in the current study was similar between groups,
and it is in agreement with previous literature. Nonetheless,
the within-group ES from pretest to 12 weeks suggest a small
advantage for the magnitude of muscle hypertrophy of
the periodized groups when compared with NP regimen
(Table 4).
Yet , a s ob s e r v e d w it h t he s t r e n g t h da t a, d e sp i t e s im i la r
increases overall, muscle hypertrophic responses differed
between groups over time. Only periodized training regimens
significantly increased QCSA in the second half of the study
(i.e., from 6 to 12 weeks). However, it is important to mention
that the magnitude of muscle hypertrophy was similar across
the group from 6 to 12 weeks. In our study, the total number of
repetitions was very similar between groups before the
commencement of the experimental period, whereas there
were no differences in volume load. Our group has previously
demonstrated that after an 8-week ST period, reductions of
;54% in volume load were sufficient to sustain QCSA during
additional 8 weeks of reduced volume load training in
untrained individuals (24). In this respect, although volume load
was not significantly different between groups, the 2 groups
that reduced volume load the most during 7–12 weeks when
compared with 1–6 weeks (i.e., TP: 220.5% and UP: 218.7%
vs. NP: 27.3 % ) a n d trai n e d a t h i gher i n t e nsit i e s w ere th e o n l y
groups to show significant muscle hypertrophy in that period.
These outcomes suggest that even in untrained individuals, ST
planning may affect the time course of muscular adaptations.
Finally, although low-load schemes have been shown to be
efficient as heavy-load regimens inducing muscle hypertrophy
(19), our findings are in agreement with previous literature in
untrained individuals demonstrating that in volume load–
equated conditions, muscle hypertrophy might favor higher
training intensities (5,11,20).
Certainly, our study has inherent limitations. For
example, although the participants were strictly instructed
to maintain their normal diet, the lack of diet control
might be a confounding factor modulating muscle hyper-
trophy in different directions. Second, longer training
periods and more exercise variation would provide further
insight into the effects of training variability on muscle
adaptations. Finally and perhaps the most important is
that periodization is not a strict defined program. Rather,
it is a concept that encompasses different ways to
manipulate training variables. In this regard, a study
scrutinizing the effects of training regimens used in our
study on muscle hypertrophy while manipulating training
variables in a different fashion might report outcomes
different from the reported herein.
In conclusion, our results demonstrated similar ST-
induced adaptations after 12 weeks of either NP or
periodized training regimens. Importantly, NP training
stimulus seems to induce suboptimal muscular adaptations
at latter training stages (i.e.,aftertheinitial6weeks),
suggesting that, even for untrained individuals, ST planning
might be important to manage fatigue and optimize
training-induced adaptations.
Strength coaches and practitioners focusing on improving
muscular adaptations in untrained individuals should be
aware that early-phase (#6 weeks) organization of training
loads does not significantly affect strength or hypertrophy,
although NP may produce slightly greater strength gains
Journal of Strength and Conditioning Research
VOLUME 32 | NUMBER 5 | MAY 2018 | 1243
Copyright © National Strength and Conditioning Association Unauthorized reproduction of this article is prohibited.
than the other groups. However, periodized ST models may
be advantageous at latter stages of training (after the initial 6
weeks), properly adjusting training stimuli and ultimately
optimizing muscular adaptations (i.e., strength performance
and hypertrophy) in untrained individuals.
E.O. De Souza was supported by CNPq 152658/2011-5. C.
Ugrinowitsch is supported by CNPq 406609/2015-2, H.
Roschel is supported by CNPq307023/2014-1, and V. Tricoli
is supported by 310823/2013-7.
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Training Regimens Effects on Muscle Strength and Mass
Journal of Strength and Conditioning Research
Copyright © National Strength and Conditioning Association Unauthorized reproduction of this article is prohibited.
... On the other hand, in nonlinear periodization models, changes in exercise volume and load are handled with reduced periodicity (daily, weekly). Regardless of the periodization model used, there is always an advantage of its use in relation to NPET for muscle strength gains (4,6,7,26,35). Several studies have been carried out to investigate the effect of periodization in the clinical setting in patients with the chronic obstructive pulmonary disease (8), coronary artery disease (22) and obesity (8,22,30). ...
... The present study found a significant increase in muscle strength (squat and handgrip) in the PET and NPET groups, in agreement with previous studies that showed increases in muscle strength after exercise training programs (16,19,36). In addition, the current study corroborates previous studies that showed greater gains in muscle strength in the PET group compared to NPET, demonstrating that both the manipulation of volume and intensity variables and the high load presented in this protocol (90% 1RM) seem to be vital to promote additional strength gains (4,6,31,35). It is noteworthy that our intervention lasted 12 weeks, as were two of the other studies mentioned above (36,4). ...
... In addition, the current study corroborates previous studies that showed greater gains in muscle strength in the PET group compared to NPET, demonstrating that both the manipulation of volume and intensity variables and the high load presented in this protocol (90% 1RM) seem to be vital to promote additional strength gains (4,6,31,35). It is noteworthy that our intervention lasted 12 weeks, as were two of the other studies mentioned above (36,4). The others lasted 24 weeks (16) and a meta-analysis included 6-24 week intervention studies (19). ...
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International Journal of Exercise Science 15(3): 733-746, 2022. The purpose of this study was to investigate the effects of two different exercise training programs periodization on anthropometric and functional parameters in people living with HIV (PLHIV). This was a randomized clinical trial that involved participants (n = 31) living with HIV aged over 18 years and undergoing antiretroviral therapy which were randomized to periodized exercise training (PET; n = 13), non-periodized exercise training (NPET; n = 13), or control group (CON; n = 15). The PET and NPET groups performed 12 weeks of combined training while the CON group maintained the usual activities. Before and after 12 weeks of intervention were measured body composition and perimeters, muscle strength, Short Physical Performance Battery (SPPB) and Timed Up and Go (TUG) test time. Results: The PET and NPET groups increased fat-free mass (p < 0,001), right (p < 0,001) and left thigh perimeter (p < 0,001), muscle strength (p < 0,001), handgrip force (p < 0,001), and reduced the fat mass (p < 0,001), neck perimeter (p < 0,001), chair stand (p < 0,001), and time-up and go test time (p < 0,001) compared to CON. Furthermore, PET was significantly different to increase right thigh and muscle strength (p < 0,05) compared to NPET. Conclusion: Both exercise training periodization protocols were effective to improve body composition and functional outcomes; however, seems that PET presents better results compare to NPET in PLHIV.
... This study reported that the larger increases in 1RM for the periodized training group in comparison to NP were greatest in the first 4 months of the training intervention and diminished over the course of the study. On the other hand, the study by De Souza et al. [32] reported no significant differences between NP and periodized resistance training during the first 6 weeks of the training intervention, whereas only periodized resistance training resulted in significant increases in 1RM squat and quadriceps muscle CSA the following 6 weeks, suggesting that the effects of periodization on strength gains and muscle hypertrophy may increase over time. As such, future research should address the question as to whether the effects of resistance training periodization increase or diminish over time, since this is beyond the scope of the present review and meta-analysis. ...
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Background In resistance training, periodization is often used in an attempt to promote development of strength and muscle hypertrophy. However, it remains unclear how resistance training variables are most effectively periodized to maximize gains in strength and muscle hypertrophy. Objective The aims of this study were to examine the current body of literature to determine whether there is an effect of periodization of training volume and intensity on maximal strength and muscle hypertrophy, and, if so, to determine how these variables are more effectively periodized to promote increases in strength and muscle hypertrophy, when volume is equated between conditions from pre to post intervention. Methods Systematic searches were conducted in PubMed, Scopus and SPORTDiscus databases. Data from the individual studies were extracted and coded. Meta-analyses using the inverse-variance random effects model were performed to compare 1-repetition maximum (1RM) and muscle hypertrophy outcomes in (a) non-periodized (NP) versus periodized training and (b) in linear periodization (LP) versus undulating periodization (UP). Subgroup analyses examining whether results were affected by training status were performed. Meta-analyses of other periodization model comparisons were not performed, due to a low number of studies. Results Thirty-five studies met the inclusion criteria. Results of the meta-analyses comparing NP and periodized training demonstrated an overall effect on 1RM strength favoring periodized training (ES 0.31, 95% confidence interval (CI) [0.04, 0.57]; Z = 2.28, P = 0.02). In contrast, muscle hypertrophy did not differ between NP and periodized training (ES 0.13, 95% CI [–0.10, 0.36]; Z = 1.10, P = 0.27). Results of the meta-analyses comparing LP and UP indicated an overall effect on 1RM favoring UP (ES 0.31, 95% CI [0.02, 0.61]; Z = 2.06, P = 0.04). Subgroup analyses indicated an effect on 1RM favoring UP in trained participants (ES 0.61, 95% CI [0.00, 1.22]; Z = 1.97 (P = 0.05)), whereas changes in 1RM did not differ between LP and UP in untrained participants (ES 0.06, 95% CI [–0.20, 0.31]; Z = 0.43 (P = 0.67)). The meta-analyses showed that muscle hypertrophy did not differ between LP and UP (ES 0.05, 95% CI [–0.20, 0.29]; Z = 0.36 (P = 0.72)). Conclusion The results suggest that when volume is equated between conditions, periodized resistance training has a greater effect on 1RM strength compared to NP resistance training. Also, UP resulted in greater increases in 1RM compared to LP. However, subgroup analyses revealed that this was only the case for trained and not previously untrained individuals, indicating that trained individuals benefit from daily or weekly undulations in volume and intensity, when the aim is maximal strength. Periodization of volume and intensity does not seem to affect muscle hypertrophy in volume-equated pre-post designs. Based on this, we propose that the effects of periodization on maximal strength may instead be related to the neurophysiological adaptations accompanying resistance training.
... Moreover, the training progression may be conducted as the practitioner gains experience (57). Furthermore, De Souza et al. (18) observed different patterns in muscular adaptations in untrained individuals, where the load variation was more effective for promoting hypertrophy after the first stage of a training program. In addition, retraining is quite a common situation in practice; thus, the subject's classification may improve the accuracy of knowing the detraining status of a practitioner. ...
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An individual’s training status is a key factor used to determine the volume, the intensity, and the selection of exercises for resistance training pre- scription. Interestingly, there are no objective parameters to assess train- ing status, so there is ambiguity in determining the appropriate volume and other resistance training variables in this regard. Thus, the objective of this study was to propose a strategy for classification and determination of resistance training status. The follow- ing five parameters were identified and used: (a) current uninterrupted training time, (b) time of detraining, (c) previous training experience, (d) exercise tech- nique, and (e) strength level. Moreover, 4 classification levels are proposed: beginner, intermediate, advanced, and highly advanced, which are determined by the mean score of the parameters used. The proposed model represents an important advancement in training status classification and can be used as a valid tool for training prescription and for researchers to better charac- terize a sample and reproduce result under the same conditions in future studies.
... It is well documented that strength training (ST) augments skeletal muscle growth across a wide spectrum of populations (4,18,20,27,37). Furthermore, ST is extensively used by strength and conditioning specialists as a means to increase muscular strength (14,19). ...
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This study compared the effects of FAST and SLOW eccentric repetition tempo in a single exercise volume-matched intervention on muscle thickness (MT) and strength in resistance-trained men. Using a within- subject design, 13 subjects had each leg randomly assigned to SLOW (1-0-3) or FAST (1-0-1) repetition tempo. Subjects un- derwent an 8-week strength-training (ST) intervention performed twice weekly. Unilateral leg-extension one repetition-maximum (1RM) and anterior thigh MT at the proximal (MTP) and distal (MTD) portions were assessed via ultrasound imaging at baseline and after 8 weeks of RT. Rating of perceived exertion (RPE) assessments of the training sessions (i.e., 16 per leg) were averaged for further analysis. Both legs similarly increased MTP (estimated differences: FAST: 0.24 cm, 3.6%; SLOW: 0.20 cm, 3.1%). However, for MTD, analysis of covariance analysis showed a leg effect (p 5 0.02) in which absolute pre-to-post change was greater in FAST compared with SLOW (estimated differences: FAST 0.23 cm, 5.5%; SLOW: 0.13 cm, 2.2%). For 1RM, both legs similarly increased maximum strength (estimated differences: FAST: 9.1 kg, 17.0%; SLOW: 10.4 kg, 22.1%, p # 0.0001). The SLOW group had a higher RPE than FAST (8.59 vs. 7.98, p 5 0.002). Despite differences in RPE, our results indicate that both repetition tempos produced similar muscular adaptations. However, they also suggest that the FAST tempo may provide a small hypertrophic advantage at the distal quadriceps. From a practical standpoint, strength and conditioning professionals may implement a FAST tempo at least in one single-joint exercise during an 8-week training period to enhance regional hypertrophic adaptations in trained individuals. Key Words: repetition speed, eccentric, concentric failure, muscle hypertrophy, RPE, volume load
... It is worth noting we used a non-periodized RT program. There is some controversy about the efficacy of periodized and non-periodized RT program between the studies on physical function and physiological health outcomes (Conlon et al. 2016, Williams et al. 2017, De Souza et al. 2018, De Freitas et al. 2019. However, recently a systematic review and meta-analyses by Afonso et al. (2019) reported no reliable evidence showing periodized RT programs are superior to a non-periodized exercise programs (Afonso et al. 2019). ...
Objective: This study aimed to determine how different resistance training protocols affect gremlin 1, macrophage migration inhibitory factor (MIF), cardiometabolic, and anthropometric measures in obese men. Methods: Forty-four males with obesity (weight: 93.2 ± 2.2 kg, BMI: 32.9 ± 1.2 kg/m2, age: 27.5 ± 9.4 years) were randomly assigned to traditional resistance training (TRT, n = 11), circuit resistance training (CRT, n = 11), interval resistance training (IRT, n = 11) or control (C, n = 11) groups. TRT group performed ten exercises at 50% of 1RM with 14 repetitions for three sets and 30 seconds rest interval between exercises and 1.5 min rest between sets, the CRT protocol included three circuits of 10 exercises, at an intensity of 50% of 1-RM, 14 repetitions with a minimum rest (< 15 s) between exercises and 3 min rest between sets, and the IRT group performed two sets of the same exercises with 50% of 1 RM, and 14 repetitions were followed with active rest of 25% of 1RM and 14 repetitions. All resistance training groups performed 60 min per session resistance exercises, 3 days per week, for 12 weeks. Measurements were taken at baseline and after 12 weeks of exercise training. Results: Resistance training (TRT, CRT, and IRT) significantly decreased plasma levels of gremlin (TRT from 231.0 ± 5.8 to 210.0 ± 11.6 ng/ml, CRT from 226.0 ± 7.6 to 188.0 ± 7.7 ng/ml and, IRT from 227.0 ± 6.3 to 183.0 ± 9.0 ng/ml, effect size (ES): 0.50), MIF (TRT from 251.0 ± 7.4 to 260.0 ± 6.5 ng/ml, CRT from 248.0 ± 10.9 to 214.0 ± 9.0 ng/ml and, IRT from 247.0 ± 8.9 to 196.0 ± 6.9 ng/ml, ES: 0.55) and CRP (TRT from 28.4 ± 1.7 to 23.3 ± 2.1 nmol/l, CRT from 28.5 ± 2.2 to 21.1 ± 1.8 nmol/l, IRT from 28.1 ± 1.3 to 20.8 ± 1.3 nmol/l, ES: 0.49) compared to the control group (p < .05), but these reduction were greater in the CRT and IRT groups compared to the TRT group (p < .05). Conclusion: The CRT and IRT protocols had more beneficial improvement in gremlin 1, MIF, body composition, and cardiometabolic risk factors compared to the beneficial changes produced by TRT protocol.
... This might lead to the misconception that it would not be possible to obtain positive results unless several different types of equipment and loads are available, as in traditional facilities. However, variation of external load, methods and exercises do not necessarily translates into greater muscle strength and hypertrophy gains De Souza et al., 2018;Baz-Valle et al., 2019;Damas et al., 2019). In this sense, proper adjustment of RT intensity and volume in order to provide an adequate muscle physiological stimulus might be more beneficial to achieve optimum gains in muscle strength and size, than to vary the RT program per se. ...
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Resistance training (RT) is a popular exercise mode and is considered an essential part of an exercise program. In current pandemic times due to the coronavirus (i.e. COVID-19) outbreak, RT practice has been strongly threatened. However, such threat might not be an inherent problem to RT, but rather to misconceptions related to RT. In the current opinion article, we provide insights to better understand RT. When analyzing current scientific evidence, it seems that RT can be performed in a safe, time-efficient and uncomplicated manner, in many different places and with few resources, which makes it fully feasible within measures adopted to control coronavirus dissemination. RT should not be sacrificed due to consequences of the coronavirus pandemic. However, it might be necessary to sacrifice some old-fashioned thoughts, rooted in beliefs that have already been overturned by science. It would be counter-productive for population health (and countries economy) to avoid RT due to the misconception that specialized equipment, fashioned programs, or resources are needed for effective programs implementation. Therefore, RT can be easily adapted to the new time and logistical challenges brought by the coronavirus outbreak. From a practical standpoint, RT could be performed using body weight, accessible materials (e.g. elastic bands, lights dumbbells and barbell) or even without external load at home or at public spaces and still result in important health benefits.
A fundamental task in exercise physiology is to determine and ultimately improve the adaptations that take place in the human body, an integrated network of various physiological systems, for example, muscle, tendon, and bone. Investigating the temporal dynamics (time course) of adaptations in these diverse systems may help us gain new knowledge about the functioning of the neuromotor system in healthy and pathological conditions. The aim of this review was to explore the temporal dynamics of muscular strength adaptations in studies implementing a resistance training intervention. In addition, we categorized these studies under mechanical or metabolic stimuli to identify whether certain stimuli cause faster muscle strength gains. Searches were performed using PubMed and Google Scholar databases. The review comprised 708 subjects from 57 training groups within 40 studies that met the inclusion criteria. The results revealed that the mean time point of first significant increase in muscle strength of all studies was 4.3 weeks, and the corresponding increase was on average about 17%. A plateau in muscle strength increase (∼25%) was found to occur between weeks 8 and 12. Categorization into stimuli groups revealed that performing training in a hypoxic environment is likely to produce a leftward shift (∼25% increase at ∼2.8 weeks) in the dose-response relationship compared with blood flow restriction and supplementation. However, stimuli that cause faster muscle strength gains may also induce imbalanced adaptation between the muscle and the surrounding biological structures, potentially triggering a degradation in some parts of the network (i.e., leading to an increased risk of injury).
This meta-analysis investigated the role of resistance training (RT) moderators on strength and muscle mass gains in untrained young (YG) and older (OG) adults. Electronic databases were searched for randomised controlled trials simultaneously assessing muscle strength and mass. Effect sizes (ES) reflecting improvements in strength and muscle mass were found for all moderators in YG and OG (ES 0.25- to 1.72;p < 0.05), excepting muscle mass in YG after RT was performed with <3 sets/exercise. Strength gains (p < 0.001) were greater in non-periodised vs. periodised RT in YG (ES 1.72 vs. 1.05) and OG (1.40 vs. 0.74). ES in OG was greater (p < 0.04) when RT included non-failure vs. failure repetitions (1.35 vs. 0.96), 3 vs. >3 sets/exercise (1.30 vs. 0.90), ≥3 vs. <3 days/week (1.70 vs. 0.78), and ≥12 vs. <12 weeks (1.48 vs. 0.92). Amoderating effect of RT factors on muscle mass was not detected in YG, while greater ES was found in OG for RT with ≥3 vs. <3 days/week (0.50 vs. 0.25). Concluding, different combinations of RT factors improved strength and muscle mass in YG and OG. In OG, this was favoured by greater frequency and duration, although hampered by excessive volume.
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Summary of the doctoral thesis Introduction: In many sports, strength is considered an important basis for performance. One factor affecting strength is muscle mass. Therefore, it may be necessary to increase muscle mass in athletes through resistance training. However, the most effective strategy to gain muscle mass has not yet been clearly identified. Many methods used in practice are based on anecdotal evidence rather than empirical data. For this reason, different approaches to hypertrophy training were examined in this thesis based on three studies. The methods and most important results of these studies are summarized in the following. Methods: In the first study, adolescent American football players completed a 12-week resistance training program with three total-body training sessions per week using either Block Periodization (BLOCK) or Daily Undulating Periodization (DUP). The aim was to investigate the effects of the different periodization strategies on muscle mass and athletic performance. The second study assessed the impact of a three-week detraining period (DTR) on anthropometric measures and sport performance. In a third study, highly trained male subjects completed a six-week low-intensity calf resistance training intervention either without (noBFR) or with blood flow restriction (BFR). Before and after the intervention, 1-RM calf raise, calf volume, muscle thickness of the gastrocnemius, and leg stiffness were recorded. Results: At the end of the first intervention, both periodization groups showed significantly higher muscle mass and thickness, as well as athletic performance without differences between groups. Following DTR, fat mass increased significantly, and fat-free mass was reduced. All other measures were unchanged after DTR. Both BFR and NoBFR training resulted in significant increases in 1-RM and muscle thickness without differences between groups. Calf volume and leg stiffness remained unchanged in both conditions. Conclusions: In adolescent American football players, the structure of periodization does not appear to have any effect on muscle growth. Furthermore, a three weeks DTR does not result in negative effects. Both results provide new insights that can be helpful when creating training programs as well as for planning training-free periods. The currently frequently investigated BFR training does not show higher effects on muscle growth of the lower extremities than conventional low-intensity resistance training.
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Over the past several decades, periodization has been widely accepted as the gold standard of training theory. Within the literature, there are numerous definitions for periodization, which makes it difficult to study. When examining the proposed definitions and related studies on periodization, problems arise in the following domains: (1) periodization has been proposed to serve as the macro-management of the training process concerning the annual plan, yet research on long-term effects is scarce; (2) periodization and programming are being used interchangeably in research; and (3) training is not periodized alongside other stressors such as sport (i.e., only resistance training is being performed without the inclusion of sport). Overall, the state of the literature suggests that the inability to define periodization makes the statement of its superiority difficult to experimentally test. This paper discusses the proposed definitions of periodization and the study designs which have been employed to examine the concept.
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The purpose of this paper was to conduct a systematic review of the current body of literature and a meta-analysis to compare changes in strength and hypertrophy between low- versus high-load resistance training protocols. Searches of PubMed/MEDLINE, Cochrane Library and Scopus were conducted for studies that met the following criteria: 1) an experimental trial involving both low- (≤60% 1 RM) and high- (>60% 1 RM) load training; 2) with all sets in the training protocols being performed to momentary muscular failure; 3) at least one method of estimating changes in muscle mass and/or dynamic, isometric or isokinetic strength was used; 4) the training protocol lasted for a minimum of 6 weeks; 5) the study involved participants with no known medical conditions or injuries impairing training capacity. A total of 21 studies were ultimately included for analysis. Gains in 1RM strength were significantly greater in favor of high- versus low-load training, while no significant differences were found for isometric strength between conditions. Changes in measures of muscle hypertrophy were similar between conditions. The findings indicate that maximal strength benefits are obtained from the use of heavy loads while muscle hypertrophy can be equally achieved across a spectrum of loading ranges.
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Background Periodization is an important component of resistance training programs. It is meant to improve adherence to the training regimen, allow for constant progression, help in avoiding plateaus, and reduce occurrence and severity of injuries. Previous findings regarding the effects of different periodization models on measures of muscle hypertrophy are equivocal. To provide a more in-depth look at the topic, we undertook a systematic review of the literature and a meta-analysis of intervention trials comparing the effects of linear periodization (LP) and daily undulating periodization (DUP) resistance training programs on muscle hypertrophy. Materials and Methods A comprehensive literature search was conducted through PubMed/MEDLINE, Scopus, Web of Science, SPORTDiscus, Networked Digital Library of Theses and Dissertations (NDLTD) and Open Access Theses and Dissertations (OATD). Results The pooled standardized mean difference (Cohen’s d) from 13 eligible studies for the difference between the periodization models on muscle hypertrophy was −0.02 (95% confidence interval [−0.25, 0.21], p = 0.848). Conclusions The meta-analysis comparing LP and DUP indicated that the effects of the two periodization models on muscle hypertrophy are likely to be similar. However, more research is needed in this area, particularly among trained individuals and clinical populations. Future studies may benefit from using instruments that are more sensitive for detecting changes in muscle mass, such as ultrasound or magnetic resonance imaging.
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Background Periodization is a logical method of organizing training into sequential phases and cyclical time periods in order to increase the potential for achieving specific performance goals while minimizing the potential for overtraining. Periodized resistance training plans are proposed to be superior to non-periodized training plans for enhancing maximal strength. Objective The primary aim of this study was to examine the previous literature comparing periodized resistance training plans to non-periodized resistance training plans and determine a quantitative estimate of effect on maximal strength. Methods All studies included in the meta-analysis met the following inclusion criteria: (1) peer-reviewed publication; (2) published in English; (3) comparison of a periodized resistance training group to a non-periodized resistance training group; (4) maximal strength measured by 1-repetition maximum (1RM) squat, bench press, or leg press. Data were extracted and independently coded by two authors. Random-effects models were used to aggregate a mean effect size (ES), 95% confidence intervals (CIs) and potential moderators. ResultsThe cumulative results of 81 effects gathered from 18 studies published between 1988 and 2015 indicated that the magnitude of improvement in 1RM following periodized resistance training was greater than non-periodized resistance training (ES = 0.43, 95% CI 0.27–0.58; P < 0.001). Periodization model (β = 0.51; P = 0.0010), training status (β = −0.59; P = 0.0305), study length (β = 0.03; P = 0.0067), and training frequency (β = 0.46; P = 0.0123) were associated with a change in 1RM. These results indicate that undulating programs were more favorable for strength gains. Improvements in 1RM were greater among untrained participants. Additionally, higher training frequency and longer study length were associated with larger improvements in 1RM. Conclusion These results suggest that periodized resistance training plans have a moderate effect on 1RM compared to non-periodized training plans. Variation in training stimuli appears to be vital for increasing maximal strength, and longer periods of higher training frequency may be preferred.
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This study investigated the effects of different reduced strength training (RST) frequencies on half-squat 1 RM and quadriceps cross-sectional area (QCSA). Thirty-three untrained males (24.7±3.9 years; 1.73±0.08m; 74.6±8.4kg) underwent a 16-week experimental period (i.e. eight weeks of strength training [ST] followed by additional eight weeks of RST). During the ST period, the participants performed 3–4 sets of 6–12 RM, three sessions/week in half-squat and knee extension exercises. Following ST, the participants were randomly allocated to one of three groups: reduced strength training with one (RST1) or two sessions per week (RST2), and ceased training (CT). Both RST1 and RST2 groups had their training frequency and total training volume-load (i.e. RST1 = 50.3% and RST2 = 57.1%) reduced, while the CT group stopped training completely. Half-squat 1 RM (RST1=27.9%; RST2=26.7%; and CT=28.4%) and QCSA (RST1 = 6.1%; RST2 = 6.9%; and CT = 5.8%) increased significantly (p < .05) in all groups after eight weeks of ST. No significant changes were observed in 1 RM and QCSA for RST1 and RST2 groups after the RST period, while the CT group demonstrated a decrease in half-squat 1 RM (22.6%) and QCSA (5.4%) when compared to the ST period (p < .05). In conclusion, different RST frequencies applied were able to maintain muscle mass and strength performance obtained over the regular ST period. Thus, it appears that RST frequency does not affect the maintenance of muscle mass and strength in untrained males, as long as volume-load is equated between frequencies. THIS MANUSCRIPT IS PROTECTED BY COPYRIGHT.
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PurposeDuring resistance training, volume and load can be altered either gradually (traditional periodization: TP) or with frequent changes between subsequent sessions (daily undulating periodization: DUP). We hypothesized that the periodization model employed would not impact upon training-induced adaptations when exercise variables are equated. Methods Nineteen females (22.0 years, moderate resistance training experience of 27.9 months) performed 6 weeks of knee extensor training with 3 weekly sessions exercising one leg using TP and the contralateral leg using DUP. Training load varied between 40, 60, and 80% of one repetition maximum (1RM). Volume, range of motion, and time under tension were equated for each leg with a biofeedback software. Dynamometry, surface EMG and ultrasonography were used to determine temporal changes of knee extensor maximum voluntary strength (MVC), neural drive of the M. quadriceps femoris (QF) and vastus lateralis (VL) and rectus femoris (RF) muscle architecture. ResultsSignificant (P < 0.05) gains for isometric (TP 15%, DUP 13%) and isokinetic-concentric (TP 8%, DUP 10%) MVC and knee extensor 1RM (TP 18%, DUP 24%) occurred post training. VL and RF-muscle thickness showed significant (P < 0.05) increases ranging from 12 to 20% for TP and from 13 to 19% for DUP. Furthermore, significant (P < 0.05) increases in VL-pennation angle and VL-fascicle length occurred in both legs while QF EMG remained unchanged. No significant temporal differences were found between both models, displaying similar small to large effect sizes. Conclusion Periodization is no adaptation trigger during short-term resistance training with equated exercise variables.
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Background: In this study, we investigated the effects of resistance training protocols with different loads on muscle hypertrophy and strength. Methods: Twenty-one participants were randomly assigned to 1 of 3 (n = 7 for each) resistance training (RT) protocols to failure: High load 80 % 1RM (8-12 repetitions) (H group), low load 30 % 1RM (30-40 repetitions) (L group) and a mixed RT protocol (M group) in which the participants switch from H to L every 2 weeks. RT consisted of three sets of unilateral preacher curls performed with the left arm 3 times/week with 90 s rest intervals between sets. The right arm served as control. Maximum voluntary contraction (MVC) of the elbow flexors (elbow angle: 90°) and rate of force development (RFD, 0-50, 50-100, 100-200 and 200-300 ms) were measured. Cross-sectional area (CSA) of the elbow flexors was measured via magnetic resonance imaging (MRI). All measurements were conducted before and after the 8 weeks of RT (72-96 h after the last RT). Statistical evaluations were performed with two-way repeated measures (time × group). Results: After 8 weeks of 3 weekly RT sessions, significant increases in the left elbow flexor CSA [H: 9.1 ± 6.4 % (p = 0.001), L: 9.4 ± 5.3 % (p = 0.001), M: 8.8 ± 7.9 % (p = 0.001)] have been observed in each group, without significant differences between groups. Significant changes in elbow flexor isometric MVC have been observed in the H group (26.5 ± 27.0 %, p = 0.028), while no significant changes have been observed in the M (11.8 ± 36.4 %, p = 0.26) and L (4.6 ± 23.9 %, p = 0.65) groups. RFD significantly increased during the 50-100 ms phase in the H group only (p = 0.049). Conclusions: We conclude that, as long as RT is conducted to failure, training load might not affect muscle hypertrophy in young men. Nevertheless, strength and RFD changes seem to be load-dependent. Furthermore, a non-linear RT protocol switching loads every 2 weeks might not lead to superior muscle hypertrophy nor strength gains in comparison with straight RT protocols.
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Resistance training increases muscle size and strength and is associated with numerous health benefits. For many, periodization serves as the cornerstone of programming for resistance training and is commonly touted in the literature as a superior method of training. Objective: To review the literature on the effects of periodization for those looking to improve muscle size and strength. Design and Methods: Non-systematic review. Research articles were collected using search terms such as linear periodization, non-linear periodization, non-periodized, undulating periodization, and strength training models. Results: Previous research has found no differences in muscle size between periodized and non-periodized training programs. Further, there are conflicting reports on what periodized program is superior for increasing muscle strength. It is our contention that the proposed superiority in strength with periodized programs is often explained by the principle of specificity. Conclusion: The use of a periodized program may be advantageous for an athlete in certain sports due to practice and competi tions throughout the season. However, we wish to suggest that the proposed benefits of periodization for those only interested in increasing muscle size and strength are largely founded in conjecture and that there is little compelling evidence that periodization is a superior method of training.
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Background It remains unclear whether repetitions leading to failure (failure training) or not leading to failure (non-failure training) lead to superior muscular strength gains during resistance exercise. Failure training may provide the stimulus needed to enhance muscular strength development. However, it is argued that non-failure training leads to similar increases in muscular strength without the need for high levels of discomfort and physical effort, which are associated with failure training. Objective We conducted a systematic review and meta-analysis to examine the effect of failure versus non-failure training on muscular strength. Methods Five electronic databases were searched using terms related to failure and non-failure training. Studies were deemed eligible for inclusion if they met the following criteria: (1) randomised and non-randomised studies; (2) resistance training intervention where repetitions were performed to failure; (3) a non-failure comparison group; (4) resistance training interventions with a total of ≥3 exercise sessions; and (5) muscular strength assessment pre- and post-training. Random-effects meta-analyses were performed to pool the results of the included studies and generate a weighted mean effect size (ES). Results Eight studies were included in the meta-analysis (combined studies). Training volume was controlled in four studies (volume controlled), while the remaining four studies did not control for training volume (volume uncontrolled). Non-failure training resulted in a 0.6–1.3 % greater strength increase than failure training. A small pooled effect favouring non-failure training was found (ES = 0.34; p = 0.02). Significant small pooled effects on muscular strength were also found for non-failure versus failure training with compound exercises (ES = 0.37–0.38; p = 0.03) and trained participants (ES = 0.37; p = 0.049). A slightly larger pooled effect favouring non-failure training was observed when volume-uncontrolled studies were included (ES = 0.41; p = 0.047). No significant effect was found for the volume-controlled studies, although there was a trend favouring non-failure training. The methodological quality of the included studies in the review was found to be moderate. Exercise compliance was high for the studies where this was reported (n = 5), although limited information on adverse events was provided. Conclusion Overall, the results suggest that despite statistically significant effects on muscular strength being found for non-failure compared with failure training, the small percentage of improvement shown for non-failure training is unlikely to be meaningful. Therefore, it appears that similar increases in muscular strength can be achieved with failure and non-failure training. Furthermore, it seems unnecessary to perform failure training to maximise muscular strength; however, if incorporated into a programme, training to failure should be performed sparingly to limit the risks of injuries and overtraining.
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Unlabelled: This study compared quadriceps muscle cross-sectional area (CSA) and maximum strength (1RM) after three different short-term strength training (ST) regimens (i.e. non-periodized [NP], traditional-periodization [TP], and undulating-periodization [UP]) matched for volume load in previously untrained individuals. Thirty-one recreationally active males were randomly divided into four groups: NP: n = 9; TP: n = 9; UP: n = 8 and control group (C): n = 5. Experimental groups underwent a 6-week program consisting of two training sessions per week. Muscle strength was assessed at baseline and after the training period. Dominant leg quadriceps CSA was obtained through magnetic resonance imaging (MRI) at baseline and 48h after the last training session. Results: The 1RM increased from pre to post only in the NP and UP groups (NP = 17.0 %, p = 0.002; UP = 12.9 %, p = 0.03), respectively. There were no significant differences in 1RM for LP and C groups after 6 weeks (TP = 7.7 %, p = 0.58, C = 1.2 %, p = 1.00). The CSA increased from pre to post in all of the experimental groups (NP = 5.1 %, p = 0.0001; TP = 4.6 %, p = 0.001; UP = 5.2 %, p = 0.0001), with no changes observed in the C group (p = 0.93). Conclusion: Our results suggest that different ST periodization regimens over a short-term (i.e. 6 weeks), volume load equated conditions seem to induce similar hypertrophic responses regardless of the loading scheme employed. In addition, for those recreational males who need to develop muscle strength in the short-term, the training regimen should be designed properly. Key pointsMuscle hypertrophy occurs within six weeks in recreationally active men regardless the ST training regimen employed.When the total volume is similar, training at greater intensities will demonstrate superior gains in the 1RM performance.Some caution should be exercised when interpreting our findings since long-term periodized regimens could produce different training-induced responses.
This study compared traditional (TP) and daily undulating (DUP) periodization on muscle strength, EMG-estimated neural drive and muscle architecture of the quadriceps femoris (QF). 10 non-athletic females (24.4±3.2 years) performed 14 weeks of isometric training for the QF exercising 1 leg using TP and the contralateral leg using DUP. Intensities varied from 60% to 80% of MVC and the intensity zones and training volume were equated for each leg. Knee extension MVC, maximal voluntary QF-EMG activity and vastus lateralis (VL) muscle architecture were measured in both legs before, after 6 weeks and after 14 weeks of training using dynamometry, surface EMG and ultrasonography. Isometric MVC and maximal QF-EMG remained unaltered after 6 weeks of training, but were significantly (P<0.05) enhanced after 14 weeks in both legs (MVC: TP 24%, DUP 23%; QF-EMG: TP 45%, DUP 46%). VL-architecture remained unchanged following 6 weeks of training, but VL-muscle thickness (TP 17%, DUP 16%) and fascicle length (TP 16%, DUP 17%) displayed significant (P<0.05) enlargements after 14 weeks in both legs. Importantly, these temporal neuromuscular alterations displayed no significant differences between the training legs. Therefore, periodization may not act as a key trigger for neuromuscular adaptations. © Georg Thieme Verlag KG Stuttgart · New York.