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BACKGROUND: Flexibility is an important component of physical fitness. However, to date, there is no comparative study between men and women concerning the influence of RT on flexibility. OBJECTIVE: To analyze the effect of RT on flexibility in young adult men and women. METHODS: Twenty-eight men and 30 women underwent progressive RT for 16 weeks, 3 times per week. Anthropometric and flexibility measurements were performed at pre-training, mid-training, and post-training. The flexibility measurements were obtained using a fleximeter. RESULTS: There was no significant sex by time interaction (P>0.05) for any outcomes. Both sexes increased flexibility similarly from baseline to mid-training in shoulder extension (10.4-11.1%) and lateral trunk inclination (2.4-3.4%). Shoulder flexion increased at same magnitude in men and women from baseline to post-training (1.3-2.8%). Hip flexion and trunk flexion scores increased from baseline to mid-training (hip flexion= 3.7-3.9%, trunk flexion= 2.7%), however, a decrease was observed from mid- to post-training (hip flexion= -2.4 - -2.6%, trunk flexion= -1.4%) with values returning to baseline with no difference between men and women. CONCLUSIONS: The results suggest that regardless of sex, RT improves or at least preserves the flexibility of different joint movements in young adult men and women.
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Isokinetics and Exercise Science 25 (2017) 149–155 149
DOI 10.3233/IES-170658
IOS Press
Effect of resistance training on flexibility in
young adult men and women
Alex S. Ribeiroa,b,, Marçal G.A. Campos-Filhob,AdemarAvelar
c, Leandro dos Santosb,
Abdallah Achour Júniorb, Andreo F. Aguiara, Steven J. Fleckd, Hélio Serassuelo Júniorband
Edilson S. Cyrinob
aCenter for Research in Health Sciences, University of Northern Parana, Londrina, Brazil
bStudy and Research Group in Metabolism, Nutrition and Exercise, Londrina State University, Londrina, Brazil
cMaringa State University, Maringa, Brazil
dAndrews Research and Education Foundation, Gulf Breeze, FL, USA
Received 1 July 2016
Accepted 27 December 2016
BACKGROUND: Flexibility is an important component of physical fitness. However, to date, there is no comparative study
between men and women concerning the influence of resistance training (RT) on flexibility.
OBJECTIVE: To analyze the effect of RT on flexibility in young adult men and women.
METHODS: Twenty-eight men and 30 women underwent progressive RT for 16 weeks, 3 times per week. Anthropometric
and flexibility measurements were performed at pre-training, mid-training, and post-training. The flexibility measurements were
obtained using a fleximeter.
RESULTS: There was no significant sex by time interaction (P>0.05) for any outcomes. Both sexes increased flexibility
similarly from baseline to mid-training in shoulder extension (10.4–11.1%) and lateral trunk inclination (2.4–3.4%). Shoulder
flexion increased at same magnitude in men and women from baseline to post-training (1.3–2.8%). Hip flexion and trunk flexion
scores increased from baseline to mid-training (hip flexion =3.7–3.9%, trunk flexion =2.7%), however, a decrease was observed
from mid- to post-training (hip flexion =2.4 −−2.6%, trunk flexion =1.4%) with values returning to baseline with no
difference between men and women.
CONCLUSIONS: The results suggest that regardless of sex, RT improves or at least preserves the flexibility of different joint
movements in young adult men and women.
Keywords: Strength training, physical fitness, range of motion, muscle mass
1. Introduction
Flexibility is important for postural stability and bal-
ance with low levels of flexibility possibly increase the
risk of osteoarticular injury, back pain, and difficult
performing activities of daily life [1]. Stretching exer-
cises are recommended for the maintenance and/or de-
Corresponding author: Alex Silva Ribeiro, Carmela Dutra Street
862, Jataizinho, 86210-000, Brazil. Tel.: +55 4332593860; E-mail:
velopment of flexibility [1]. However, resistance train-
ing (RT), in addition to muscular strength and body
composition benefits [2], has been shown as a viable
alternative for increasing flexibility in various popula-
tions [314]. Changes induced by RT on muscle archi-
tecture, density of myofilaments, and structure of con-
nective tissue, may improve flexibility by a reduction
in passive tension and stiffness of the tissues surround-
ing a joint. Thus RT may be a time saving strategy to
increase flexibility and so may aid adherence to an in-
tervention program among some populations. In fact,
ISSN 0959-3020/17/$35.00 c
2017 – IOS Press and the authors. All rights reserved
150 A.S. Ribeiro et al. / Flexibility and resistance training
there is evidence that regular RT serves as an active
form of flexibility training and can improve range of
motion to a similar extent as typical static stretching
protocols [8].
Despite the growth in the number of studies in-
vestigating the influence of RT on flexibility, the ma-
jority of previous investigations have evaluated short
to medium length training durations, between 4 to
12 weeks [6,810,13,15,16]. Thus the chronic effects
of RT on flexibility are largely unknown. Moreover,
men and women present different levels of flexibil-
ity [17], and therefore the chronic adaptations of flexi-
bility due to RT may be different between the sexes.
Given the above background and considering that, to
our knowledge, there is no comparative study between
men and women concerning the influence of RT on
flexibility, it seems relevant to investigate the chronic
effects of RT on flexibility between sexes.
2. Methods
2.1. Participants
Participants were recruited from a university popu-
lation and though local advertisement. All volunteers
(47 women and 42 men) completed a detailed health
history questionnaire. Inclusion criteria were the fol-
lowing: no signs or symptoms of any disease or ortho-
pedic injuries, inactive (defined as performing physical
activity less than twice a week), and no participation
in any RT for at least six months before the beginning
of the study. Twenty-eight men and 30 women finished
the study and therefore were included in the final anal-
ysis. The reasons for subject dropout included insuf-
ficient attendance of training sessions (<85% of the
total sessions) and voluntary abandonment for various
personnel reasons.
Written informed consent was obtained from all sub-
jects after a detailed description of the study proce-
dures was provided. This investigation was conducted
according to the Declaration of Helsinki, and was ap-
proved by the local University Ethics Committee.
2.2. Anthropometry and skeletal muscle mass
Body mass was measured to the nearest 0.1 kg us-
ing a calibrated electronic scale (Balmak, Laboratory
Equipment Labstore, Curitiba, PR, Brazil), with the
participants wearing light workout clothing and no
shoes. Height was measured to the nearest 0.1 cm with
a stadiometer attached to the scale with participants
standing without shoes. Body mass index was calcu-
lated as body mass in kilograms divided by the square
of height in meters.
Skeletal muscle mass was estimated using the pre-
diction equation of Lee et al. [18], validated by Gobbo
et al. [19]:
SMM (kg)= 0.244 ×BW +7.8×H+6.6×S
0.098 ×A+R3.3
where BW =body weight (kg), H =height (m), S =
sex (male =1, female =0), A =age (years), R =race
(1.2 for Asians, 1.4 for African-Americans and 0 for
2.3. Flexibility measurements
Nine joint movements were evaluated in the follow-
ing order: right shoulder extension, left shoulder ex-
tension, right shoulder flexion, left shoulder flexion,
right hip flexion, left hip flexion, frontal trunk flexion,
right trunk inclination, and left trunk inclination. All
measurements were obtained using a fleximeter (Code,
American do Brazil Ltda, São Paulo, Brazil) with a
degree scale. All measurements were performed ac-
cording to procedures and recommendations described
elsewhere [20].
Briefly, for shoulder extension, shoulder flexion, and
hip flexion measurements, the participants were lying
on a stretching table in a supine position with the upper
limbs parallel to the body line, elbow extended and the
palm of the hand facing the stretching table with the
fleximeter positioned in the medial portion of the par-
ticipants’ arm. For shoulder extension, the upper limb
was lowered below the edge of the stretching table,
while for shoulder flexion the upper limb was moved
above the edge of the stretching table. For hip flexion,
the fleximeter was positioned on the lateral mid-point
of the thigh, the hip was flexed as far as possible with-
out the back elevating off of the stretching table, the
knee remained extended during this movement.
Trunk flexion was measured in a standing position,
the fleximeter was positioned next to the hip just above
the iliac crest, shoulders vertically flexed, elbows ex-
tended, fingers intertwined, and legs together, the sub-
ject then performed forward hip flexion as far as pos-
sible while keeping the knees extended. Lateral trunk
inclination was measured in the standing position with
legs together and the knees extended, the fleximeter
was placed on the medial surface of the thoracic spine,
arms crossed over the trunk and hands on the contralat-
eral shoulder. Participants then performed lateral hip
A.S. Ribeiro et al. / Flexibility and resistance training 151
inclination as far as possible with the heels remaining
in contact with the floor.
For all movements, after attaching the fleximeter
with Velcro straps and setting the zero point of the
fleximeter, the participants executed the movement as
far as possible or until the feeling of tightness or dis-
comfort at the end of the range of motion. At the end
of the range of motion the evaluator recorded the mea-
surement. Subjects remained in the final position until
the measurement was completed. Three measurements
were obtained for each joint movement without any
warm-up. The highest score obtained from the three
measurements in each joint motion was used in the sta-
tistical analysis.
The same evaluator performed all measurements
pre-, mid- and post-training. The evaluator was blinded
to previous scores in successive measurements (pre-,
mid- and post-training). The evaluator had over 2 years
experience in measuring flexibility, and based on test-
retest data, the technical error of measurement and
the intraclass correlation coefficient among the move-
ments was 2.26 degrees and 0.950, respectively.
The maximal technical error among the movements an-
alyzed was 1.19 degrees.
The flexibility measurements were performed in
a University controlled-temperature laboratory room
(22–24C). The experiment was conducted during the
spring and summer seasons.
2.4. Muscular strength
Maximal dynamic strength was evaluated using the
one repetition maximum (1RM) test in the free-weight
bench press (BP), squat on a smith machine (SQ), and
free-weight arm curl (AC), in that order, at baseline
and after 16 of the RT period. In BP the grip was such
that the thumbs were at shoulder width when the bar
was resting on the support standards. Complete range
of motion consisted of lowering the bar until it touched
the chest and pressing it upward until locking the el-
bows at the top of the press; the subjects were not al-
lowed to arch the back and bounce the bar of their
chest. For the SQ, the bar of the Smith machine was
placed at approximately the level of the upper trapez-
ius muscle and rubber padding cushioning the region.
The feet were parallel and placed shoulder width apart.
The complete range of motion consisted of lowering
the body, flexing the knees to a 90angle, then press-
ing forward and upward until the knees were locked.
For execution of AC, the participants stood with their
back against a wall to prevent any assistive motion,
and the knees were positioned with a slight flexion.
From a full arm-extended position, hands in supina-
tion, placed slightly wider than shoulder width and di-
rectly under the bar, AC was executed using the ante-
rior arm flexor muscles through approximately a 120-
deg range of motion or until the full flexion of the el-
The rest periods between exercises ranged from
three to five minutes. The test in each exercise was pre-
ceded by a warm-up set (6–10 repetitions) with 50%
of the estimated load used in the first attempt of the
1RM test. The testing procedure was initiated two min-
utes after warm-up. The subjects were oriented to try
to accomplish two repetitions with the imposed load in
three attempts in each exercise. If the subject was suc-
cessful in the first attempt, weight was added (3–10%
of the first attempt load), a 3–5 min rest was given, and
a second attempt was made. If this attempt was suc-
cessful, a third attempt was given with an increased
load (3–10% of the second attempt load), following a
3–5 min rest. If the subject was not successful in the
first or second attempt, weight was removed (3–10% of
the previous attempt load) and one other attempt was
given. The 1RM was recorded as the last resistance
lifted in which the subject was able to complete one
single full-range maximum execution.
Execution technique and form of each exercise were
standardized and continuously monitored to promote
reliability in the maximum strength assessment. All
the sessions were supervised by three experienced re-
searchers for greater safety and integrity of the subjects
during tests. Four 1RM sessions were performed sepa-
rated by 48 hours. The highest load among the three fi-
nal sessions was used for analysis in each exercise. The
intraclass correlation coefficients for 1RM in BP, SQ
and AC were 0.98, 0.91, and 0.96 respectively. Dur-
ing all sessions, subjects were allowed to drink water
whenever necessary and were encouraged to remain
hydrated throughout testing.
2.5. Resistance training program
A supervised progressive RT program designed to
induce muscular hypertrophy was performed in 2
phases of 8 weeks each, 3 times per week on noncon-
secutive days (Monday, Wednesday, and Friday) [2].
The RT sessions were conducted at a University facil-
ity. All subjects were individually supervised by expe-
rienced instructors during each training session in or-
der to reduce deviations from the study protocol and to
ensure subject safety. Subjects performed RT using a
combination of free weights and machines, and the ex-
152 A.S. Ribeiro et al. / Flexibility and resistance training
Tab le 1
General characteristics of the sample at baseline
Men (n=28 ) Women (n=30) P
Age (years) 22.1 ±4.3 22.4 ±4.0 0.79
Body mass (kg) 68.4 ±9.2 57.7 ±10.2 <0.001
Height (cm) 174.4 ±6.7 162.3 ±6.4 <0.001
Body mass index (kg.m2)22.5 ±2.4 21.8 ±3.2 0.40
Note: Data are presented as mean and standard deviation.
Tab le 2
Flexibility of different articular movements and skeletal muscle mass at different moments
Men (n=28) Women (n=30) ANCOVA effects P
Skeletal muscle mass (kg)
Pre-training 31.6 ±2.8 21.4 ±3.2 Time 0.04
Mid-training 31.9 ±2.721.7 ±3.2Interaction 0.84
Post-training 32.1 ±2.7∗† 21.9 ±3.3∗†
Right shoulder extension (degrees)
Pre-training 85.4 ±14.0 87.0 ±9.1 Time <0.001
Mid-training 93.3 ±13.398.3 ±9.4Interaction 0.22
Post-training 93.4 ±13.196.4 ±9.2
Left shoulder extension (degrees)
Pre-training 84.3 ±13.3 88.3 ±7.7 Time <0.001
Mid-training 92.6 ±12.598.0 ±11.6Interaction 0.26
Post-training 94.0 ±13.196.6 ±9.6
Right shoulder flexion (degrees)
Pre-training 185.6 ±13.1 185.8 ±23.4 Time <0.001
Mid-training 187.3 ±12.3 184.8 ±26.9 Interaction 0.35
Post-training 189.4 ±14.3∗† 192.3 ±10.1∗†
Left shoulder flexion (degrees)
Pre-training 186.3 ±16.3 190.5 ±11.7 Time <0.001
Mid-training 186.5 ±13.4 189.2 ±12.3 Interaction 0.53
Post-training 190.6 ±11.8∗† 191.1 ±10.7∗†
Right hip flexion (degrees)
Pre-training 94.1 ±13.5 102.8 ±15.9 Time <0.01
Mid-training 98.4 ±12.6106.2 ±15.5Interaction 0.81
Post-training 95.4 ±14.9104.0 ±16.0
Left hip flexion (degrees)
Pre-training 93.4 ±12.9 103.9 ±16.5 Time <0.001
Mid-training 97.1 ±12.3107.5 ±14.0Interaction 0.45
Post-training 95.6 ±12.5104.0 ±14.4
Frontal trunk flexion (degrees)
Pre-training 143.1 ±12.6 144.8 ±18.5 Time <0.001
Mid-training 146.6 ±10.1149.2 ±11.4Interaction 0.23
Post-training 143.8 ±11.3147.9 ±11.0
Right trunk inclination (degrees)
Pre-training 51.5 ±9.3 51.0 ±7.5 Time <0.001
Mid-training 53.8 ±9.152.2 ±6.8Interaction 0.71
Post-training 53.9 ±8.653.0 ±7.2
Left trunk inclination (degrees)
Pre-training 49.1 ±8.8 52.6 ±6.8 Time <0.01
Mid-training 51.1 ±8.353.0 ±7.2Interaction 0.37
Post-training 51.9 ±8.753.0 ±7.4
Note: Data are presented as mean and standard deviation. p<0.05 vs pre-training. p<0.05 vs Mid-training.
ercises included total body and body part exercises of
the upper limbs, trunk and lower limbs. The progres-
sive RT program in the first phase consisted of 9 exer-
cises selected to stress the major muscle groups. The
exercises were performedin the following order: bench
press, leg press 45, wide-grip behind-the-neck pull-
down, leg extension, side lateral raise, lying leg curl,
triceps pushdown, calf press on the leg press machine,
and arm curl.
In the second phase, the RT program was altered,
and 11 exercises were performed in the following
order: bench press, incline dumbbell fly, wide-grip
A.S. Ribeiro et al. / Flexibility and resistance training 153
Tab le 3
Muscular strength at pre-training and after 16 weeks of resistance training
Men (n=28) Women (n=30) ANCOVA effects P
Bench press (kg)
Pre-training 61.9 ±2.9 29.5 ±1.2 Time <0.001
Post-training 74.8 ±2.838.1 ±1.3Interaction 0.07
Squat (kg)
Pre-training 118.7 ±3.9 75.6 ±2.8 Time <0.05
Post-training 133.8 ±3.887.8 ±3.4Interaction 0.54
Arm curl (kg)
Pre-training 37.2 ±1.3 21.6 ±0.7 Time <0.001
Post-training 42.9 ±1.326.1 ±0.8Interaction 0.27
Note: Data are presented as mean and standard deviation. p<0.05 vs pre-training.
behind-the-neck pulldown, seated cable rows, seated
barbell military press, lying triceps press, arm curl,
leg extension, leg press 45, lying leg curl, and seated
calf raise. After the resistance exercises, the abdominal
crunch exercise was performed on the floor using the
subject’s bodyweight (3 sets of 50–100 repetitions in
both phases).
For both phases, all subjects performed 3 sets of 8–
12 repetitions at a 8–12 repetition maximum resistance
for each of the exercises except for the calf exercises
(3 sets of 15–20 maximum repetitions), and were in-
structed to perform repetitions with a concentric-to-
eccentric phase ratio of 1:2 seconds. The rest period
between sets was 60–90 s, with a 2–3 min rest inter-
val between each exercise. Subjects were encouraged
to perform all sets to voluntary concentric muscular
failure. The training load was consistent with the pre-
scribed number of repetitions for the 3 sets of each ex-
ercise. The load was adjusted weekly using the weight
test of maximum repetitions as described by Ribeiro et
al. [21]. The subjects were instructed not to perform
any other type of exercise during the study period.
2.6. Statistical analyses
For comparisons between sex, two-way analysis of
covariance (ANCOVA) for repeated measures were
used, with baseline scores used as a covariate. In vari-
ables where sphericity was violated as indicated by
Mauchly’s test, the analyses were adjusted using a
Greenhouse-Geisser correction. When an F-ratio was
significant, Fisher’s post hoc test was employed to
identify where significant mean differences existed.
For all statistical analyses, significance was accepted
at P<0.05. The data were stored and analyzed us-
ing STATISTICA software version 10.0 (Statsoft Inc.,
Tulsa, Ok , USA).
3. Results
Table 1 displays the general characteristics of the
participants at baseline. As expected, men had greater
mass and were taller compared to women (P<0.05).
Changes in skeletal muscle mass and flexibility at
the different time points of the study are presented in
Table 2. There was no group (sex) by time interaction
(P>0.05) for any of the outcomes analyzed. A sig-
nificant main effect of time (P<0.05) was observed
for skeletal muscle mass, shoulder extension, shoul-
der flexion, hip flexion, frontal hip flexion, and lateral
trunk inclination. Both sexes presented a similar mag-
nitude of increase in skeletal muscle mass from pre- to
mid-training (+1.2%) and from mid- to post-training
(+0.8%). Both sexes increased similarly in flexibil-
ity from baseline to mid-training in shoulder extension
(10.4–11.1%) and lateral trunk inclination (2.4–3.4%).
Hip flexion and trunk flexion also increased similarly
in men and women from baseline to mid-training (hip
flexion =3.7–3.9%, trunk flexion =2.7%), however,
a decrease toward baseline was observed from mid-
to post-training (hip flexion =2.4 – 2.6%, trunk
flexion =1.4%) without a difference between sexes.
While shoulder flexion increased similarly in men and
women from baseline to post-training (1.3–2.8%).
Changes in muscular strength are presented in Ta-
ble 3. Both sexes showed significant increases in 1RM
scores for BP (men =+20.8%; women =+29.2%),
SQ (men =+12.7%; women =+16.1%), and AC
(men =+15.3%; women =+20.8%) with no statisti-
cal significant difference between sexes.
4. Discussion
The main and novel finding of our study was that
the adaptations in flexibility induced by RT are joint
and time-dependent regardless of the individuals’ sex
154 A.S. Ribeiro et al. / Flexibility and resistance training
since men and women presented similar magnitudes of
change in flexibility. Increases in flexibility due to a
RT program, in some joints trained and not all joints
trained, have been previously reported in untrained
adult women [6,8,9,11,12,15], untrained adult men [8,
12,14,22], older women [3], older men [4,5], resistance
trained individuals [13], and judo athletes [10].
The exact mechanisms responsible for increased
flexibility induced by a RT program are not yet es-
tablished and the outcomes drawn from our study do
not provide mechanistic insight. Nevertheless, we can
speculate on possible causes. Joint movement is related
to morphological elements such as muscle, bone, and
connective tissue. In particular, muscle and fascia are
responsible for 41% of a joint’s resistance to move-
ment [23], suggesting that an RT-mediated reduction
in passive tension and stiffness of these tissues trans-
lates into a greater range of motion [24], however, this
hypothesis requires further study.
Our results indicate a joint-dependent adaptation.
For example, shoulder flexion flexibility increased sig-
nificantly after the second 8-weeks of RT, while the
others joints increased significantly after the first 8-
weeks of RT. A plausible explanation for this outcome
may be related to the characteristics of the movement
and exercise in which a joint was involved. For exam-
ple, in the second 8-week RT period more exercises
that included shoulder movement were performed the
exercise incline dumbbell fly was included in the RT
program, which is an exercise requiring a large range
of motion of shoulder which would potentially re-
sult in increased shoulder flexion flexibility. Our re-
sults concerning increased shoulder flexibility only af-
ter the second 8-weeks of RT agree with a previous
study [15] in which shoulder flexibility did not signifi-
cantly change due to 10 weeks of RT in sedentary adult
women (mean age =37 years). On the other hand,
Saraiva et al. [10] have reported increases in shoulder
flexion of male judo elite athletes after 12 weeks of
RT-period. Two other studies [4,5] observed increases
in shoulder flexibility of older men after 8, 12, and
24 weeks of RT. Collectively these studies indicate that
increases in shoulder flexion due to RT may be time
and/or age-dependent. Future investigations are war-
ranted to confirm this hypothesis.
Shoulder extension and lateral trunk inclination in-
creased in the first 8-week training period, but did not
increase further in the second 8-weeks of training. This
adaptation pattern followed the typical adaptation pat-
tern to RT of a large initial adaptation that is dependent
on an individual’s RT training experience [25,26], and
further adaptations after the initial training period be-
come progressively smaller as training experience in-
creases because the so-called “window of adaptation”
decreases during long-term RT [27]. This may explain
the initial significant increase in flexibility in the un-
trained subjects who participated in this study. The
adaptation pattern of initial large increases in flexibil-
ity followed by a plateau of further flexibility increases
may indicate the need for specific flexibility training
after the initial increase due to performing only RT.
After the initial increases in flexibility from baseline
to the end of the first 8-weeks of training, decreases
in flexibility after the first 8 weeks to the end of the
second 8-weeks of training occurred for trunk and hip
flexion. These decreases returned flexibility to baseline
values. The reason for these findingsare not readily ap-
parent and warrant replication in future studies. How-
ever, long-term RT does not decrease flexibility and in-
creases in hypertrophy do not result in decreased flexi-
bility. For example, competitive Olympic weightlifters
have average or above average flexibility [28].
The present investigation has some limitations. The
results cannot be extrapolated to other populations
other than health young adult men and women or to
longer or shorter training durations. A strength of the
study is, to the authors’ knowledge, this study is the
first report comparing changes in flexibility between
the sexes due to performing the same resistance train-
ing program.
5. Conclusion
The results observed in this study suggest that RT
improves or at least preserves the flexibility of differ-
ent joint movements in young adult men and women.
In addition, these changes are dependent on the dura-
tion of the RT program and are not affected by the in-
dividuals’ sex.
Conflict of interest
The authors declare no conflict of interest.
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... However, many of the responses induced by RT appear to be sex-dependent 1-5 due to differences in muscular strength and mass, hormonal regulation, muscular architecture, energy storage, use of energy substrates, the muscular recovery process, and motor unit recruitment patterns, while other adaptive responses manifest themselves regardless of sex. 2,4,[6][7][8][9][10] Salvador et al. 1 revealed the presence of sexual dimorphism in strength endurance in women presenting a better response than men in multiple sets to failure, with 80% of one-repetition maximum (1-RM) after eight weeks of RT. On the other hand, the fatigue index improved similarly in both groups. ...
... The increase in muscular strength caused by RT in men and women under the same RT protocol has already been documented in previous studies, lasting eight 1,6 and sixteen weeks. 2,5,10 Nevertheless, to our knowledge, this is the first study that analyzed the behavior of maximum strength and strength endurance on different body segments based on sex, allowing us to observe the behavior of these variables after eight and sixteen weeks. Therefore, we examined the responses by considering Note. ...
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Introduction Although resistance training (RT) can provide numerous benefits for both men and women, morphological, neuromuscular, metabolic, physiological, and behavioral differences between sexes may influence the magnitude of training responses. Objective To analyze the impact of 16 weeks of progressive RT on strength endurance in untrained men and women. Methods Twenty-eight men and 31 women (18-30 years) underwent a supervised RT program that was divided into two 8-week stages, 3 times per week on nonconsecutive days. The RT program was composed of exercises for different body segments (trunk, upper and lower limbs) that were performed with three sets of 8-12 repetitions maximum (RM), in 10 and 12 exercises, in the first and second stage, respectively. Strength endurance was assessed in 3 exercises (bench press, squat, and arm curl) and in a combination of these exercises through a protocol composed of 4 sets performed to failure with 80% of 1-RM on the baseline, after 8 and 16 weeks of RT. Results Group vs. time interactions (p <0.05) were found for bench press (men = +28.3% vs. women = +32.1%), squat (men = +13.5% vs. women = +32.7%), and arm curl (men = +20.2% vs. women = +24.4%) exercises, as well as in the set of all 3 exercises (men = +18.4% vs. women = +31.2%). Conclusion Our results suggest that 16 weeks of RT can improve strength endurance in both men and women, although higher gains are achieved by women. Level of evidence II; Therapeutic study-Investigating treatment results.
... U některých souborů, resp. intervencí nedošlo ke zlepšení, nicméně opět není reportován snížený parametr flexibility žádné části těla (Leite et al., 2015;Ribeiro et al., 2017). Vše nasvědčuje tomu, že spíše výběr cviků bude mít určující vliv na změny ve flexibilitě. ...
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Cílem textu je poskytnout vědecky podloženou evidenci k teorii tonických a fázických svalů včetně souvisejících vlastností (tendencí) z různých hledisek. Text je členěn na Rozlišení tonických a fázických svalů, Svalová vlákna, Inervace svalu, Zkrácení svalu, Tonus svalu, Oslabení svalu. Pro hledání relevantních zdrojů byly použity databáze PubMed, Semantic Scholar, Scopus. České zdroje byly hledány prostřednictvím Google Scholar,, případně nebo v knihovních systémech.
... It shows that FWT improves the muscles of the back, hip and thigh. Ribeiro et al. (2017) reported that resistance training improves the flexibility of different joint movements in young adult men and women. Also, free weights' training improves lower back flexibility better than other conventional resistance training (Ojo, 2019). ...
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The advent in technology makes people to spend less time doing physical work while incidence of sedentariness and musculoskeletal disorders increases rapidly. Since schools students enjoy screen-based activities which is sedentariness, free weights training have the potentials of accommodating such personalities while training the body. Physical performance variables include: arm strength (AS), arm power (AP) and lower back flexibility (LBF) and are required in carrying out daily activities. The study adopted the frequency, intensity, time and type (FITT) principles of fitness training. The pretest-posttest control group quasi experimental design was used. Eighty participants (forty males and forty females) selected from two secondary schools in Ondo town were randomly assigned to free weights training (FWT) and control groups. The treatment lasted for twelve (12) weeks. Data were analysed using descriptive statistics of frequency count and percentages as well Analysis of Covariance to test the hypotheses at .05 level of significance. There were significant main effects of treatment on the physical fitness variables of AS (F (1,77) =136.526; P<.05; η 2 =.639), AP(F(1,77)= 178.091; P<.05; η 2 =.698) and LBF (F(1,77)= 294.186; P<.05; η 2 =.793). The FWT was potent at improving physical fitness variables; AS, AP and F of secondary school students. Therefore, the youth should engage in FWT for health benefits and improved physical fitness regardless of their stature.
... This means that the average male needs more practice to obtain better flexibility. Although, Ribeiro et al. (2017), findings reported that regardless of sex, resistance training improves the flexibility of different joint movements. ...
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This study, therefore, examined the comparative effects of two modes of resistance training viz: Variable Resistance Training (VRT) and Free Weights Training (FWT) on MPS of adolescents. The pretest, post-test, control group quasi-experimental design was adopted. Participants included 179 adolescents (90 males and 89 females) from six secondary schools in Ondo, Nigeria. Standardized instruments used were multi-gym machine, barbells, medicine balls, dumbbells, flex box and hand-grip dynamometer. The experimental group was exposed to VRT and FWT for twelve weeks while the control group was taught the concepts of training. Data analysis employed Analysis of Covariance. Treatment had significant effect on AS with better improvement in FWT group and control group. Gender also had significant effect on AS with better performance by males than females. The interaction effect of treatment and gender was significant on AS. The two modes of training improved the adolescents' motor performance skills to a large extent, therefore, should be adopted by trainers towards improving adolescents motor performance skills.
... These mechanisms are discussed elsewhere [246,247]. Nevertheless, resistance training-a mode of exercise that involves repeated actions of muscle lengthening and shortening against external load through full ROM-increases sit-and-reach scores (10-25%) [224,[248][249][250][251][252][253][254][255] (Table 2) and other measures of ROM equal to stretching [256][257][258][259][260][261] ( Table 3). Other papers also report increased flexibility after resistance training but do not contain explicit statements about the exclusion of supplemental stretching [262][263][264][265][266][267][268]. ...
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Flexibility refers to the intrinsic properties of body tissues that determine maximal joint range of motion without causing injury. For many years, flexibility has been classified by the American College of Sports Medicine as a major component of physical fitness. The notion flexibility is important for fitness has also led to the idea static stretching should be prescribed to improve flexibility. The current paper proposes flexibility be retired as a major component of physical fitness, and consequently, stretching be de-emphasized as a standard component of exercise prescriptions for most populations. First, I show flexibility has little predictive or concurrent validity with health and performance outcomes (e.g., mortality, falls, occupational performance) in apparently healthy individuals, particularly when viewed in light of the other major components of fitness (i.e., body composition, cardiovascular endurance, muscle endurance, muscle strength). Second, I explain that if flexibility requires improvement, this does not necessitate a prescription of stretching in most populations. Flexibility can be maintained or improved by exercise modalities that cause more robust health benefits than stretching (e.g., resistance training). Retirement of flexibility as a major component of physical fitness will simplify fitness batteries; save time and resources dedicated to flexibility instruction, measurement, and evaluation; and prevent erroneous conclusions about fitness status when interpreting flexibility scores. De-emphasis of stretching in exercise prescriptions will ensure stretching does not negatively impact other exercise and does not take away from time that could be allocated to training activities that have more robust health and performance benefits.
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The main purpose of the investigation reported here was to analyze the effect of resistance training (RT) performed at different weekly frequencies on flexibility in older women. Fifty-three older women (≥60 years old) were randomly assigned to perform RT either two (n=28; group "G2x"), or three (n=25; group "G3x") times per week. The RT program comprised eight exercises in which the participants performed one set of 10-15 repetitions maximum for a period of 12 weeks. Anthropometric, body-composition, and flexibility measurements were made at baseline and post-study. The flexibility measurements were obtained by a fleximeter. A significant group-by-time interaction (P<0.01) was observed for frontal hip flexion, in which G3x showed a higher increase than G2x (+12.8% and +3.0%, respectively). Both groups increased flexibility in cervical extension (G2x=+19.1%, G3x=+20.0%), right hip flexion (G2x=+14.6%, G3x=+15.9%), and left hip flexion (G2x=+25.7%, G3x=+19.2%), with no statistical difference between groups. No statistically significant differences were noted for the increase in skeletal muscle mass between training three versus two times a week (+7.4% vs +4.4%, respectively). Twelve weeks of RT improves the flexibility of different joint movements in older women, and the higher frequency induces greater increases for frontal hip flexion.
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The aim of this study was to examine the effects of twelve weeks of resistance training with different exercise orders (upper limbs and lower limbs vs. lower limbs and upper limbs) on flexibility levels in elite judo athletes. Thirty-nine male athletes were randomly divided into 3 groups as follows: G1 (n = 13), G2 (n = 13), and CG (n = 13). The flexibility was assessed on 8 joint movements: shoulder flexion and shoulder extension, shoulder abduction and shoulder adduction, trunk flexion and trunk extension, and hip flexion and hip extension. Two-way repeated measures ANOVAs (time [pre-experimental vs. post-experimental] × group [G1 vs. G2 vs. CG]) were used to compare the differences between pre- and post-test situations and the differences among groups. The results from the within-group (pre vs. post) comparisons demonstrated significant increases (p < 0.05) in the range of motion of 3.93 and 5.96% for G1 and G2 training groups, respectively, in all joints. No significant changes (p > 0.05) were observed for the CG. The results from the between-group comparisons demonstrated no significant differences (p > 0.05) in the range of motion between G1post vs. G2post (1.15%). Although both exercise orders (from upper to lower limbs and from lower to upper limbs) increased flexibility, no significant variations were observed between the different exercise orders. Nevertheless, these findings demonstrate that flexibility gains could be obtained with a resistance training program, and thus, more time can be devoted to sports-specific judo training.
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Influence of the Number of Sets at a Strength Training in the Flexibility Gains The aim of this study was to investigate the effects of 10 weeks of strength training with different number of sets and their influence on flexibility of young men. Sixty men were divided into three groups as follows: group that trained 1 set per exercise (G1S), group that trained 3 sets per exercise (G3S) and control group (CG). The training lasted 10 weeks, totaling 30 training sessions. The training groups performed 8 to 12 repetitions per set for each exercise. The flexibility at Sit and Reach Test was evaluated pre and post-training. Both trained groups showed significant increase in flexibility when compared to pre-training and the G3S showed significant difference when compared to CG post-training. According to this study, the strength training carried out without flexibility training promotes flexibility gains regardless the number of sets.
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Traditional weight training programs utilize an exercise prescription strategy that emphasizes improving muscle strength through resistance exercises. Other factors, such as stability, endurance, movement quality, power, flexibility, speed, and agility are also essential elements to improving overall functional performance. Therefore, exercises that incorporate these additional elements may be beneficial additions to traditional resistance training programs. The purpose of the study was to compare the effects of an isolated resistance training program (ISO) and an integrated training program (INT) on movement quality, vertical jump height, agility, muscle strength / endurance, and flexibility. The ISO program consisted of primarily upper and lower extremity progressive resistance exercises. The INT program involved progressive resistance exercises, as well as core stability, power, and agility exercises. Thirty subjects were cluster-randomized to either the ISO (n=15) or INT (n=15) training program. Each training group performed their respective programs 2-times per week for 8 weeks. Subjects were assessed before (pre-test) and after (post-test) the intervention period using the following assessments: a jump-landing task graded using the Landing Error Scoring System (LESS), vertical jump height, T-test time, push-up and sit-up performance, and sit-and-reach test. The INT group performed better on the LESS test (pre-test: 3.90±1.02, post-test: 3.03±1.02; P=0.02), faster on the T-test (pre-test: 10.35±1.20s, post-test: 9.58±1.02s; P=0.01), and completed more sit-ups (pre-test: 40.20±15.01, post-test: 46.73±14.03; P=0.045) and push-ups (pre-test: 40.67±13.85, post-test: 48.93±15.17, P=0.05) at post-test compared to pre-test, and compared to the ISO group at post-test. Both groups performed more push-ups (P=0.002), jumped higher (P<0.001), and reached further (P=0.008) at post-test compared to pre-test. Performance enhancement programs should use an integrated approach to exercise selection in order to optimize performance and movement technique benefits.
The rheological properties of the cat”s wrist were found to be similar to those of the human metacarpophalangeal joint. In the intact joint nonlinear elasticity and plasticity accounted for most of the stiffness, elasticity being twice as great as plasticity. Inertia accounted for <6% of the total torque, and viscosity <2%. Frictional torques were immeasurably small, being <0.1% of the total. The joint capsule contributed 47%, passive motion of the muscles 41%, the tendons 10%, and the skin 2% to the total torque required to move the joint in its midrange. Toward the extremes of joint motion the restraining effect of tendons became more important. Submitted on February 8, 1962
The aim of this study was to analyze the strength and flexibility gains after 12 weeks of strength and flexibility training (FLEX), isolated or combined. Twenty-eight trained women (age = 46 ± 6.52 years; body mass = 56.8 ± 5.02 kg; height = 162 ± 5.58 cm; mean ± SD) were randomly divided into 4 groups: strength training (ST) (n = 7), FLEX (n = 7), combination of strength and flexibility (ST + FLEX) (n = 7), and combination of flexibility and strength (FLEX + ST) (n = 7). All groups were assessed before and after training for the sit and reach test, goniometry, and 10 repetition maximum in bench press (BP) and leg press (LP) exercises. The training protocol for all groups included training sessions on alternate days and was composed of 8 exercises performed at periodized intensities. The FLEX consisted of dynamic stretching performed for a total duration of 60 minutes. The results demonstrated significant strength gains in all groups in the LP exercise (FLEX: p = 0.0187; ST: p = 0.0001; FLEX + ST: p = 0.0034; ST + FLEX: p = 0.0021). All groups except the FLEX improved in BP strength (FLEX: p = 0.1757; ST: p = 0.0001; FLEX + ST: p = 0.0017; ST + FLEX: p = 0.0035). Statistical analyses did not show significant differences between groups; however, effect sizes demonstrated slightly different treatment effects for each group. Largest treatment effects were calculated for the ST group (LP: 2.72; BP: 1.25) and the lowest effects in the FLEX group (LP: 0.41; BP: -0.06). Both combination groups demonstrated lower effect sizes for both LP and BP as compared with the ST group. No significant differences in flexibility were seen in any group, in any of the comparisons (p > 0.05). In conclusion, these findings suggest that combining strength and FLEX is not detrimental to flexibility development; however, combined training may slightly reduce strength development, with little influence of order in which these exercises are performed.
The purpose of this study was to analyze the specific training load during a resistance training (RT) programme designed to increase muscular hypertrophy in men and women. Thirty-four women (22.7 ± 4.1 years, 58.8 ± 11.9 kg, 162.6 ± 6.2 cm and 22.1 ± 3.6 kg.m −2) and 30 men (22.7 ± 4.4 years, 68.4 ± 9.0 kg, 174.5 ± 6.6 cm and 22.5 ± 2.4 kg.m −2) underwent a supervised RT programme that was divided into two phases of 8 weeks each. Training consisted of 10–12 exercises performed with three sets of 8–12 repetitions at repetition maximum resistances performed 3 times per week on nonconsecutive days. There was a significant (P < 0.05) main effect for gender by time interaction for average training load of all the exercises performed in the first 8 weeks of RT with women showing a higher relative increase than men (+43.6% vs. +32.5%, respectively). This result was not observed during the second 8-week phase of the RT programme during which no significant gender by time interaction (P > 0.05) was shown with both genders having a similar relative increase (+28.7% vs. +24.3%, respectively). Women had a higher increase than men in specific average training load of the upper limb exercises during both the first 8 weeks of training (+30.2% vs. +26.6%, respectively) and the second 8 weeks of training (+31.1% vs. +25.3%, respectively). We conclude that the adaptation in specific training load is influenced by gender.
The aim of this study was to analyze the flexibility behavior of different articulations after 10 weeks of resistance training (RT). That is why, 16 inactive men (23.0 ± 2.1 years; 68.0 ± 7.0 kg; 178.8 ± 8.7 cm) apparently healthy were randomly divided into training group (TG, n = 8) and control group (CG, n = 8). The group TG was submitted to 10 consecutive weeks of RT (three weekly sessions in alternated days), whereas for group CG, no systematized program of physical activities was developed in this period. The 11 exercised that composed the RT program were performed in three series of 8-12 RM. The shoulder flexion and extension, trunk flexion, lateral flexion and extension, hip extension and flexion, elbow extension and flexion and knee flexion were used for the analysis of the flexibility behavior. The ANOVA and ANCOVA for repeated measures, followed by the Tukey post hoc test for P < 0.05 were used for data treatment. Significant increase on flexibility between pre and post experiment were found in TG in shoulder flexion movements (right hemisphere, P < 0.05), hip extension (left hemisphere, P < 0.05), trunk extension (P < 0.05), trunk flexion (P < 0.05) and trunk lateral flexion (right hemisphere, P < 0.05; left hemisphere, P < 0.01). Although, the effect of the interaction group vs time was only identified in elbow flexion movements (right and left hemisphere, P < 0.05), hip extension (left hemisphere, P < 0.05) and trunk lateral flexion (left hemisphere, P < 0.01). Thus, the results of the present study suggest that the 10 first weeks of RT practice may contribute effectively for the maintenance or improvement of the flexibility levels observed in the pre-training period, in different articulations.
Many people believe that weight training decreases flexibility. Because of the popularity of weight training today, there are difference types of programs to develop strength, endurance and bulk. There is a need to know more about various weight-training programs and their possible effects on flexibility. The purpose of this ex-post facto study was to compare right shoulder and elbow flexibility in male bodybuilders, college football players, students from an overload conditioning class, olympic-style lifters and students from a control group. All subjects were male volunteers in excellent health. The bodybuilders were members of three weight-training clubs in one county. The football players were both starters and nonstarters from an NAIA college, while the students from an elective overlad conditioning class were involved in a basic weight-training program twice a week and also jogged once or twice a week. The olympic-style lifters were members of the teams involved in any weight-training program and had not been involved for the previous six months. Circumference measurements of the subjects were taken at the right shoulder, upper arm, forearm and chest, and subjects performed the following flexibility tests: right shoulder joint flexion, shouolder joint hyperextension, shoulder joint horizontal flexion, shoulder joint horizontal extension and elbow joint flexion. All measurements were made with a protractor-type goniometer. Percent body fat was estimated from generalized equaltions. Significant differences existed on the five flexibility measurments. Further analyses reveled that the olympic-style lifters and the other groups on all measurements. Finally, selected muscle girths, skinfolds and percent fat were not good predictors of right shoulder and elbow flexibility. (C) 1991 National Strength and Conditioning Association
The aim of this study was to analyze the validity of anthropometric equations to identify changes in skeletal muscle mass (SMM) after resistance training (RT). Anthropometric and dual energy x-ray absorptiometry (DXA) measurements were obtained at baseline and after RT in 15 trained Caucasian college men. Participants performed RT over 8 weeks, consisting of 8-9 exercises of 4 sets with 12/10/8/6 maximal repetitions and 1-2 min interval between sets. The training loads were gradually increased according to gains in muscular strength. 4 anthropometric equations were used for estimation of SMM: EQ1 (SMM, g=height×[0.0553×corrected thigh girth2 + 0.0987×forearm girth2 + 0.0331×corrected calf girth2] - 2445), EQ2 (SMM, g=height×[0.031×medial thigh girth2 + 0.064×corrected calf girth2 + 0.089×corrected arm girth2] - 3006), EQ3 (SMM, kg=height×[0.00744×corrected arm girth2 + 0.00088×corrected thigh girth2 + 0.00441×corrected calf girth2] + 2.4×gender - 0.048×age + race + 7.8) and EQ4 (SMM, kg=0.244×weight + 7.8×height + 6.6×gender - 0.098×age + race - 3.3). EQ1 and EQ2 overestimated the SMM (41.3% and 19.9%, respectively; P<0.05) while EQ3 and EQ4 were similar (P>0.05) to DXA at baseline. Although all equations and DXA revealed a significant increase in SMM after RT, changes were overestimated by EQ1 and EQ2 (P<0.05), but not by EQ3 and EQ4 (P>0.05). In addition, changes in SMM over time between EQ4 and DXA were significantly correlated (r=0.62; P<0.01). Thus, changes in SMM that occur after RT can be detected by EQ4 in trained young men.