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A single set of low intensity resistance exercise immediately following high intensity resistance exercise stimulates growth hormone secretion in men

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Abstract

The purpose of the present study was to examine the effects of an additional set immediately following high intensity resistance exercise on growth hormone (GH) response. Subjects (n=8) performed 4 resistance exercise protocols (bilateral knee extension exercise) on separate days. The protocols were categorized into 2 types of protocol, namely "Strength-up type (S-type)" and "Combination type (Combi-type)". The S-type was resistance exercise which consisted of 5 sets at 90% of 1 repetition maximum (RM) with 3-min rest periods between sets, whereas the Combi-type is a training protocol which adds an additional set (either 50% of 1 RM [C50-type], 70% of 1 RM [C70-type] or 90% of 1 RM [C90-type]) to the S-type. Serum GH concentration and blood lactate concentration were determined pre-exercise and at 0-60 min postexercise. Relative changes in thigh girth and maximal unilateral isometric strength were determined pre-exercise and immediately postexercise. The increasing values of GH concentration (DGH) in the S-type was the lowest of all protocols. On the other hand, DGH in the C50-type showed a significantly (p<0.05) higher increase than in the S-type and C90-type, and a relatively higher increase than in the C70-type. These results suggests that a high intensity, low volume training protocol to induce neural adaptation resulted in little GH response, but GH secretion was increased by performing a single set of low intensity resistance exercise at the end of a series of high intensity resistance sets.
Growth Hormone Response
International Journal of Sport and Health Science Vol.2, 111-118, 2004
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111
1. Introduction
Regimens in resistance exercise training have been
generally categorized into two major types according
to objectives: "strength-type" and "hypertrophy-type".
The former consists of high-intensity exercises [1-8
between sets (approximately 2-5 min), and is used
to increase maximal muscular strength. The latter
consists of moderate-intensity exercises (8-15 RM)
with short rest periods between sets (approximately
0.5-2 min), and has been thought to be effective
in gaining muscle size and muscular endurance
[Kraemer et al. (1987); Fleck & Kraemer (1997);
Choi et al. (1998)].
The mechanism for the speci c training effects of
the "strength-type" and "hypertrophy-type" regimens
involves many factors,; i.e., mechanical, metabolic,
neural and endocrine factors. Among endocrine
factors, actions of anabolic hormones such as growth
hormone (GH) and testosterone (TES) have been
clearly shown to stimulate protein synthesis and to
promote muscle hypertrophy [Florini (1987)]. From
this viewpoint, a number of studies have investigated
acute anabolic hormone responses in males and
females [Kraemer et al. (1990, 1993)], and young
and elderly subjects [Häkkinen & Pakarinen (1995)].
These studies show that many types of resistance
exercise appear to stimulate secretions of anabolic
hormones, but the responses of hormones, especially
Growth Hormone Response to Training Regimen with
Combined High-and Low-Intensity Resistance Exercises
Kazushige Goto
*
,
Naokata Ishii
**
,
and
Kaoru Takamatsu
***
*
Institute of Health and Sport Sciences, University of Tsukuba, Japan Society for the Promotion of Science
1-1-1 Tennodai, Tsukuba, Ibaraki 305-8574 Japan
gotoh@ tness.taiiku.tsukuba.ac.jp
**
Department of Life Sciences, Graduate School of Arts and Sciences, University of Tokyo
Komaba, Meguro-ku, Tokyo 153-8902 Japan
***
Institute of Health and Sport Sciences, University of Tsukuba
1-1-1 Tennodai Tsukuba, Ibaraki 305-8574 Japan
[Received November 7, 2003 ; Accepted April 6, 2004]
We had previously shown that performing a single set of resistance exercise at 50% of 1
repetition maximum (RM) added after a high-intensity, low-repetition exercise (strength-type
regimen) greatly enhanced growth hormone (GH) secretion [Goto et al. (2003)]. The present
study aimed to investigate the effect of an additional set at 50% to 20% of 1RM after a
strength-type regimen on anabolic hormone secretion. Eight male subjects performed
bilateral knee extension exercises using a strength-type regimen (5 sets at 90% of 1RM, with
3-min rests), and other 3 types of regimens, in which 1 set of exercise at either 50%, 30% or
20% of 1RM was added immediately after the strength-type regimen (de ned as C50-type,
C30-type and C20-type regimens, respectively). Concentrations of serum GH, testosterone
and blood lactate were measured before and after exercises. The number of repetitions in the
added set showed a signi cant dependence on the exercise intensity: 82.3 times in C20-type >
46.1 times in C30-type > 22.6 times in C50-type (
p
46.1 times in C30-type > 22.6 times in C50-type (p46.1 times in C30-type > 22.6 times in C50-type (
0.05). Post-exercise GH concentrations
were signi cantly (
p
were signi cantly (pwere signi cantly (
0.05) higher in C50- and C30-type regimens than in the strength-type
regimen, whereas no signi cant difference was observed between C20- and strength-type
regimens. Testosterone did not change in any types of regimen. These results indicated that
performing a single set of exercise at low intensity added after a strength-type regimen caused
a signi cant increase in GH concentration. However, such an effect might be diminished
when the intensity of the additional exercise was extremely low (below 20% of 1RM).
Keywords:
blood lactate, muscular strength, muscular hypertrophy
Paper : Coaching and Training
[International Journal of Sport and Health Science Vol.2, 111-118, 2004]
International Journal of Sport and Health Science Vol.2, 111-118, 2004
Goto, K., Ishii, N., and Takamatsu, K.
http://wwwsoc.nii.ac.jp/jspe3/index.htm
112
GH, are relatively small after high-intensity and
low-repetition exercises such as those used in the
"strength-type" regimen [Kraemer et al. (1990, 1993);
Häkkinen & Pakarinen (1993); Goto et al. (2003b)].
Because some earlier studies indicate a positive
correlation of the magnitude of GH or TES responses
with either strength impr oveme nt [kkinen et
al. (2001); Hansen et al. (2001)] or muscle ber
effects can be expected if secretion of these hormones
is separately stimulated after a "strength-type"
regimen.
We had previously evaluated the GH concentrations
after varied exercise regimens, in which a single set of
exhaustive exercise at either 90% 1RM, 70% 1RM or
50% 1RM was added after a "strength-type" regimen.
Our results indicated that performing an additional
set of exercise at 50% of 1RM immediately after a
"strength-type" regimen caused a marked increases
in blood lactate and serum GH concentrations [Goto
et al. (2003a)]. Moreover, we had shown that this
type of exercise regimen increased maximal muscular
strength and cross sectional area (CSA) more than a
conventional "strength-type" regimen in a periodized
training period [Goto et al. (in press)].
As mentioned above, the acute and long-term
effects of an exercise regimen with combined high-
and low-intensity (50% of 1RM) resistance exercises
were investigated, and we were curious to know
whether a single set of extremely low intensity (below
50% of 1RM) exercise added to the "strength-type"
exercise following a "strength-type" regimen
might cause a greater hormonal secretion due to
augmentations of the number of repetition and total
work volume. However, blood in ow through the
artery would not be suppressed by the force exertion
at below 20% of maximal isometric strength [Edwards
et al. (1972)], and no great changes in metabolic
condition could be expected in the working muscle
by the added low-intensity exercise. Since it has
been suggested that a local accumulation of metabolic
subproducts (e.g., lactate, proton) would stimulate
secretion of GH through hypothalamic-pituitary
axis [Takarada et al. (2000); Stokes et al.(2002)],
the effects of additional exercise with extremely low
intensity on hormonal secretions might be little.
In the present study, we investigated the effects of
a single set of exercise with an intensity ranging from
50% to 20% of 1RM added after a "strength-type"
low-intensity enhanced hormonal secretion.
2. Methods
2.1. Subjects
Eight healthy male subjects (age: 24.9 ± 0.7 years,
height: 175.8 ± 1.2 cm, body mass: 71.3 ± 2.5 kg,
% fat: 18.9 ± 0.9 %) participated in this study. The
subjects were graduate students and had a minimum
resistance training experience for several years. They
did not take part in regular training program at the
beginning of the present study. They were informed
about the experimental procedure to be utilized as
well as the purpose of the present study, and their
written informed consent was obtained. The study
was approved by the Ethics Committee for Human
Experiments, Institute of Health and Sport Sciences,
University of Tsukuba.
2.2. Experimental design and exercise protocol
Bilateral knee extension with an isotonic machine
was used as the resistance exercise. The same
equipment used in our previous studies was prepared
in the present study. The range of the movement was
from 90˚ to 180˚ (180˚ was de ned as full extension).
Prior to the testing, the subjects participated in a
familiarization period consisting of a total of 2 visits,:
one visit to familiarize with the exercise protocol, and
the other to measure 1RM of bilateral knee extension
exercise.
All subjects performed 4 regimens of resistance
exercise in a random order. The time interval between
each exercise was more than 6 days.
Figure 1
shows
protocols for each type of exercise regimen.
The
Set
Strength-type
(S-type) 1 2 3 4 5
3-min
90 90 90 9090
90 50
30-s
3-min
90 90 9090
1 2 3 4 5 6
C50-type
C30-type
C20-type
90 30
90 90 9090
1 2 3 4 5 6
90 20
90 90 9090
1 2 3 4 5 6
Fig. 1. Protocols for resistance exercise. Exercise intensity (% of
1RM) is denote d in each column repres ent ing each s et. The
exe rcises in every set of e very protocol were lasted until the
subjects failed to continue the movement.
Figure 1
Protocols for resistance exercise. Exercise
intensity (% of 1RM) is denoted in each column
representing each set. The exercises in every set of every
protocol were lasted until the subjects failed to continue
the movement.
Growth Hormone Response
International Journal of Sport and Health Science Vol.2, 111-118, 2004
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113
strength-type (S-type) regimen consisted of ve sets
at 90% 1RM with 3-min rest periods between sets.
This protocol was designed to gain maximal muscular
strength. A single set of exercise at 50%, 30% and
20% of 1RM was added following the last set of the
S-type regimen with a rest period of 30-s. These
C20-type regimens, respectively. In the added set,
the subjects were instructed to lift and lower the load
at a constant velocity and frequency (approximately
40 times/min). This type of regimen is similar to
an S-type regimen, and an additional set of exercise
was performed in order to increase anabolic hormone
concentrations of blood [Goto et al. (2003a)]. The
exercises in every set of every protocol were lasted
until the subjects failed to continue the movement.
These exercise regimens were based on our previous
study using additional sets at 90-50 % of 1RM. The
subjects were allowed to drink water
ad libitum
until
the resting blood sample was obtained.
2.3. Measurements of blood sample
Venous blood samples were obtained from the
antecubital vein of the subjects in a seated position
(10 ml for each point of measurements) before and
15-min after each exercise. This sampling timing was
determined based on the observation of our previous
study, in which the maximal GH concentration was
observed 15-min after the exercise when the blood
samples were consecutively obtained until 60-min
after similar type of exercise [Goto et al. (2003a)].
Moreover, because many studies have shown that
the highest concentrations of serum GH and TES are
seen from 0 to 30 min after various types of exercise
the post-exercise concentrations in the present study
(15 min after exercise) appeared to be near the peak
level. All blood samples were collected at the same
time of the day to reduce the effects of any diurnal
variations of the hormonal response [Thuma et al.
(1995)]. Following the overnight fast, the subjects
came to the laboratory at 8:30 – 9:00 a.m., and took a
blood samples were centrifuged at 3000 rpm for 10
min to obtain serum, and serum samples were stored
at
-85
C
C
C
until analysis. To eliminate variances among
the measurements, all the samples were analyzed by
the same kits used in our previous study. In addition,
as many samples as possible were assayed in the same
run. The concentration of serum GH was measured
through radioimmunoassay (RIA) using kits from
Daiich Radioisotope Lab (Tokyo, Japan). The limit
of detection for GH assay was 0.05 ng/ml. The
inter-assay coef cient of variation (CV) was 3.6%,
and the intra-assay CV was 3.4 %. The concentration
of total testosterone (TES) was measured through
RIA using kits from DPC Corporation (Chiba, Japan).
The limit of detection for TES assay was 5.0 ng/dl.
The inter-assay CV was 5.3 %, and the intra-assay
CV was 5.8 %. Blood samples from ngertip for
measurement of lactate concentration were also
obtained before and 5-min after each exercise.
Blood lactate concentration was determined using an
automatic lactate analyzer (YSI 1500 sport, Yellow
Springs Instruments, OH).
Some previous studies have shown that plasma
volume acutely decreases following a resistance
exercise [Ploutz-Snyder et al. (1995); Raastad
et al. (2000)], and this in uences the hormone
concentrations of blood. However, in the present
study, hormone concentrations were presented as
non-corrected values due to the fact that tissues were
exposed to an absolute molar concentration [Kraemer
et al. (1992)].
2.4. Measurements of muscular strength and
thigh girth
Maximal isometric strength (MIS) of the unilateral
knee extension exercise was measured before and
immediately after exercises, to assess muscular
fatigue. The subjects sat on a dynamometer
(COMBIT, MINATO Instrument, Tokyo, Japan) with
keeping the knee angle at 100˚ (180˚ was de ned as
full extension) and were instructed to exert maximal
isometric strength for 3-s. The highest value among
2-3 trials was adopted as the MIS value. Intra-class
correlation coef cient (between measurements) was:
= 0.84 for measurement of MIS.
The thigh girth of the left leg was also measured
before and 3-min after each exercise. Measurement
of the thigh girth was performed twice at the midpoint
of the thigh (a middle point between the trochanter
major and the lateral epicondylus of bula), and the
mean value was adopted as the thigh girth value.
Acute exercise-induced changes in the thigh girth
indicated the increased water content in the activated
International Journal of Sport and Health Science Vol.2, 111-118, 2004
Goto, K., Ishii, N., and Takamatsu, K.
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114
muscle caused by local accumulations of metabolites
[N ygren et al . (20 00)]. Intr a-class co rrelation
coef cient (between measurements) was:= 0.98 for
measurement of thigh girth.
2.5. Statistical analysis
Data are expressed as means ± SE. Differences
among the regimens were assessed using a two-way
analysis of variance (ANOVA) with repeated
measures and Fisher’s post hoc comparison.
Differences for paired data were examined using
student’s paired t-test. Selected bivariate relationships
were investigated using a peason product moment
correlation coef cient. P values of less than 0.05
were considered to be statistically signi cant.
3. Results
3.1. Weight, the number of repetition, work
volume, and average power in the additional set
The number of repetitions from 1st to 5th sets
in all regimens showed similar values (range from
3 to 8 times), and no signi cant difference was
seen among the regimens. Weight, the number of
additional set (the 6th set) are shown in
Table 1
. The
data were consistent with experimental conditions of
the additional set using 50% to 20% of 1RM. The
absolute values of the weight were signi cantly
greater in the C50-type regimen than in the C30-type
and C20-type regimens, whereas the number of
Consequently, the work volume (weight × repetition)
of the additional set showed a signi cantly greater
value in the C20-type regimen than in the C50-type
and C30-type regimens. Average power output (work
volume / exercise duration) of the additional set was
signi cantly greater in the C50-type regimen than in
the C30-type and C20-type regimens.
3.2. Changes in growth hormone, testosterone
and blood lactate
Changes in GH concentration after exercise are
shown in
Figure 2
. The pre-exercise data showed
no signi cant difference in the GH values among
the regimens. Serum GH concentration in all the
regimens increased after exercise, and signi cant
changes were seen after the C50-type (pre: 1.4 ±
0.9 ng/ml, post: 7.9 ± 3.4 ng/ml) and C30-type
regimens (pre: 0.3 ± 0.1 ng/ml, post: 7.2 ± 3.0 ng/ml).
Post-exercise GH concentrations were signi cantly
higher in the C50-type and C30-type regimens than in
the S-type regimen, but no signi cant difference was
Table 1
Weight, the number of repetitions, work volume and average power in the additional set.
Weight (Kg) Number of repetition Work volume (J) Average power (W)
C50-type 57.1 ± 1.9C30, C20 22.6 ± 1.3 1298.8 ± 102.2 38.1 ± 1.3C30, C20
C30-type 34.1 ± 1.2C20 46.1 ± 3.9C50 1574.1 ± 155.0C50 22.7 ± 0.8C20
C20-type 22.9 ± 0.9 82.3 ± 5.9C30, C50 1907.5 ± 200.0C30, C50 15.3 ± 0.6
C20-type regimens, respectively.
Table 1. Weight, the number of repetitions, work volume and average power in the
Values are
means SE. Work volume was calculated as training
weight the number of
duration. C50, C30, C20;p0.05, compared to corresponding values of C50-type, C30-type and
repetition. Average power was calculated by dividing the work volume by the exercise
additional set.
Figure 2
Changes in serum growth hor mone concentration after
exercise of each regimen. S, C50, C30 and C20 indicate S-type,
C50 - t y pe, C30 - t y pe and C20-t y p e r egi m ens , r esp e ctively.
Values are means ± SE. *;
p
0.05, compared to pre-exercise
value. #;
p
≤ 0.05, compared to corr espond ing value of the
S-type regimen.
0
2
4
6
8
10
12
Serum growth hormone
S C50 C30 C20
(ng/ml)
Pre-exercise
Post-exercise
*
#
*
#
Fig. 2. Changes in serum growth hormone concentration after
exercise of each regimen. S, C50, C30 and C20 indicate S-type,
C50-type, C30-type and C20-type regimens, respectively. Values
are means ± SE. *; p 0.05, compared to pre-exercise value. #; p
0.05, compared to corresponding value of the S-type regimen.
Growth Hormone Response
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115
observed between the C20-type and S-type regimens
(p=0.14).
Changes in TES concentration after exercise are
shown in
Figure 3
. The pre-exercise data showed no
signi cant difference in TES concentrations among
the regimens. Serum TES concentration in all the
were not signi cant in any types of regimen. In
addition, relative changes of TES were not correlated
with those of GH (S-type: r=-0.14, p=0.75; C50-type:
C20-type: r=0.01, p=1.00).
Ch anges in bloo d lactate co n centrat i on after
exercises are shown in
Figure 4
. Again, the
pre-exercise data showed no signi cant difference in
the blood lactate concentrations among the regimens.
Blood lactate concentration signi cantly increased
after exercise in all the regimens, and post-exercise
values were signicantly higher in the C50-type,
C30-type and C20-type regimens than in the S-type
regimen. However, no signi cant difference was
observed among these 3 types of regimen.
3.3. Changes in maximal isometric strength
and thigh girth
Changes in MIS and thigh girth after exercise
are shown in
Table 2
. MIS signi cantly decreased
after exercise in all the regimens except the S-type
regimen, and post-exercise value in the C30-type
regimen was signi cantly lower than that in the
S-type regimen. However, no signi cant difference
in MIS was observed among the C50-type, C30-type
Figure 3
Changes in ser um testosterone concent ration af ter
exercise of each regimen. S, C50, C30 and C20 indicate S-type,
C50 - t y pe, C30 - t y pe and C20-t y p e r egi m ens , r esp e ctively.
Values are means ± SE.
0
100
200
300
400
500
600
700
S C50 C30 C20
Serum testosterone
(ng/dl) Pre-exercise
Post-exercise
Fig. 3. Changes in serum testosterone c oncentrat ion after
exercise of each regimen. S, C50, C30 and C20 indicate S-type,
C50 -t ype, C30-type and C20-t ype regi men s, respectiv el y.
Values are means ± SE.
Figure 4
Changes in blood lactate concentration after exercise
of each regimen. S, C50, C30 and C20 indicate S-type, C50-
type, C30-type and C20-type regimens, respectively. Values are
means ± SE. *;
p
≤ 0.05, compared to pre-exercise value. #;
p
0.05, compared to corresponding value of the S-type regimen.
0
1
2
3
4
5
6
S C50 C30 C20
Blood lactate
(mmol/l)
Pre-exercise
Post-exercise *
#*
#
*
#
*
Fig. 4. Changes in blood lactate concentration after exercise of
each regimen. S, C50, C30 and C20 indicate S-type, C50-type,
C30-type and C20-type regimens, respectively. Values are means
± SE. *; p0.05, compared to pre-exercise value. #; p0.05,
compared to corresponding value of the S-type regimen.
Table 2
Changes in maximal isometric strength (MIS) and thigh girth after exercise of each regimen.
after exercise of each regimen.
Pre-exercise Post-exercise
Maximal isometric strength (Nm)
S-type 287.7 ± 17.6 272.8 ± 16.4 C30
C50-type 295.5 ± 12.7 249.5 ± 13.7*
C30-type 300.0 ± 16.3 236.8 ± 15.1*
C20-type 296.5 ± 16.2 244.2 ± 17.4*
Thigh girth (cm)
S-type 52.9 ± 1.4 53.2 ± 1.4*
C50-type 53.0 ± 1.4 53.8 ± 1.4*
C30-type 52.8 ± 1.3 53.6 ± 1.3*
C20-type 53.0 ± 1.3 53.5 ± 1.4*
C30;p 0.05, compared to corresponding value of the C30-type regimen.
Table 2. Changes in maximal isometric strength (MIS) and thigh girth
Values are means ± SE. *; p 0.05, compared to pre-exercise value.
International Journal of Sport and Health Science Vol.2, 111-118, 2004
Goto, K., Ishii, N., and Takamatsu, K.
http://wwwsoc.nii.ac.jp/jspe3/index.htm
116
and C20-type regimens.
Thigh girth consistently increased after exercise
in all the regimens, indicating that uid was shifted
from the vascular space into the activated muscle
[Ploutz-Snyder et al. (1995)]. However, the
post-exercise data showed no signi cant difference
among the regimens.
4. Discussion
Although many types of resistance exercise
appear to stimulate secretions of anabolic hormones
(e.g., growth hormone, testosterone), the type of
training regimen has been shown to greatly affect
the magnitude of hormone responses, especially that
of GH [Häkkinen & Pakarinen (1993); McCall et al.
(1999)]. According to Kraemer et al. (1990, 1991,
1993), regimens using moderate exercise intensity,
moderate repetitions (10RM) and short rest periods
between sets (1-min) considerably enhance GH
secretion, whereas those using higher intensity, lower
sets (3-min) do not. Our results showed that the
GH response to only the S-type regimen was small
(
Figure 2
), which was consistent with the results of
Kraemer et al. (1990).
Although the actual effects of circulating GH on
muscular adaptation are poorly understood, McCall
et al. (1999) and Häkkinen et al. (2001) have reported
that acute changes in GH are positively correlated
with changes in the muscle ber cross sectional area
and muscular strength after a prolonged training.
Furthermore, Hansen et al. (2001) have recently
shown that an increase in elbow exor strength was
greatly enhanced when GH release was stimulated
by performing an additional leg press exercise
immediately after the arm curl exercise. These
studies suggest that exercise-induced increase in
blood GH concentration plays, in part, a role in the
muscular adaptation to resistance exercise.
The aim of the present study was to investigate
the magnitude of GH and TES responses to different
exercise regimens, in which a single set of exercise
at 50% to 20 % of 1RM was added after an S-type
which the intensity of the additional single set of
exhaustive exercise ranged from 90% to 50% of 1RM.
In this range of intensity, 50% of 1RM exercise gave
addition, a similar type of regimen with an additional
set at approximately 50 % of 1RM had been shown
to increase muscular strength more than the S-type
regimen [Goto et al. (in press)]. In the present study,
the concentration of GH was signi cantly increased
by adding a set of exercise with a low-intensity
ranging 50% to 30% of 1RM to an S-type regimen.
This suggested that an additional set of low-intensity,
high-repetition exercise was practically important for
enhancement of GH secretion, even if the exercise
intensity in the additional set was lower than 50%
of 1RM. It was also observed that relative changes
in serum GH concentration after the C50-type and
C30-type regimens were greater than those after the
C20-type regimen with larger work volume, although
the differences were not signi cant (
Table 1
and
Figure 2
). The reason for this was unclear, and larger
work volume would not be necessarily a crucial
factor for the enhancement of GH secretion in this
type of exercise regimen. In addition, our previous
and present results suggested that an additional set
of exercise with approximately 50% of 1RM had a
greater effect on the increase of GH concentration.
Post-exercise values of blood lactate and serum
GH were not signi cantly different among the
regimens with additional set (
Figure 2
and
Figure
4
). In addition, relative changes in thigh girth and
MIS immediately after exercises were similar in these
regimens. A rapid increase in working muscle size is
primarily caused by increased water content within
the muscles because of metabolite accumulation
[Ploutz-Snyder et al. (1995)], and this leads to
muscular fatigue and concomitant acute decrease in
MIS [Häkkinen & Pakarinen (1995)]. Therefore, the
present results implied the lack of marked differences
in exercise-induced metabolite changes and muscular
fatigue among the regimens with an additional set.
TES production is thought to be involved in the
anabolic process in both the human and animal
muscles [Pearlman & Crepy (1967); Volek et al.
(1997)]. It has been shown that TES concentration
elevates after resistance exercises with moderate
intensity, short rest periods and suf cient exercise
duration, even though changes in its concentration
are much smaller than those in GH concentration
[Kraemer et al. (1990); Häkkinen & Pakarinen
(1995)]. However, the magnitude of TES responses
after all exercise regimens was small and not
signi cant. Exercises using larger muscle groups
(e.g., bench press, deadlift, squat, leg press), and
Growth Hormone Response
International Journal of Sport and Health Science Vol.2, 111-118, 2004
http://wwwsoc.nii.ac.jp/jspe3/index.htm
117
those with larger work volume might be required to
make serum TES level fully elevate.
In conclusion, although meaningful GH increase
was not observed after an S-type regimen, the
secretion of GH was signi cantly enhanced by
performing an additional set of low intensity, high
S-type regimen. However, secretion of GH would
not be induced, when the intensity of the additional
exercise was extremely low (below 20% of 1RM).
There were several limitations in interpreting the
present results. Investigations with the larger number
of subjects, and more frequent measurements of
establish the effectiveness of the present training
mechanism of this training regimen to stimulate GH
secretion might need further elucidation.
References
Choi, J. Y., Masuda, K., Muraoka, M., Shimojo, H., & Takamatsu,
K. (1998). The difference between effects of "power-up type"
and "bulk-up type" strength training exercises (2) – with special
reference to muscle ber characteristics and capillary supply.
Japanese Journal of Physical Fitness and Sports Medicine, 47,
189-198 (in Japanese).
Edwards, R. H., Hill, D. K., & McDonnell, M. (1972).
Myothermal and intramuscular pressure measurements during
isometric contractions of the human quadriceps muscle. Journal
of Physiology, 224, 58P-59P.
Fleck, S.J., & Kraemer, W.J. (1997) Resistance training and
exercise prescription. In Designing resistance training programs
(2nd ed.). (pp. 81-179). Champaign: Human Kinetics.
Florini, J. R. (1987). Hormonal control of muscle growth. Muscle
Nerve, 10, 577-598.
Goto, K., Sato, K., & Takamatsu, K. (2003a). A single set of
low intensity resistance exercise immediately following high
intens ity res istan ce exer ci se stim ulate s growt h hor mone
secretion in men. Journal of Sports Medicine and Physical
Fitness, 43, 243-249.
Goto, K., Choi, J., Ohyama, K., & Takamatsu, K. (2003b).
Differences in characteristic between Strength-up type and
Bulk-up type of resistance exercise: with reference to EMG
activity and growth hormone secretion. Japan Journal of
Physical Education, Health and Sport Sciences, 48, 383-393 (in
Japanese).
Goto, K., Nagasawa, M., Yanagisawa, O., Kizuka, T., Ishii, N., &
Takamatsu, K. (in press). Muscular adaptations to combinations
of high- and low-intensity resistance exercises. Journal of
Strength and Conditioning Research.
Häkkinen, K., & Pakarinen, A. (1993). Acute hormonal responses
to two different fatiguing heavy-resistance protocols in male
athletes. Journal of Applied Physiology, 74, 882-887.
Häkkinen, K., & Pakarinen, A. (1995). Acute hormonal responses
to heavy resistance exercise in men and women at different
ages. International Journal of Sports Medicine, 16, 507-513.
Häkkinen, K., Pakarinen, A., Kraemer, W. J., Häkkinen,
A., Valkeinen, H., & Alen, M. (2001). Selective muscle
hypertrophy, changes in EMG and force, and serum hormones
during strength training in older women. Journal of Applied
Physiology, 91, 569-580.
Hansen, S., Kvorning, T., Kjaer, M., & Sjogaard, G. (2001). The
effect of short-term strength training on human skeletal muscle:
the importance of physiologically elevated hormone levels.
Scandinavian Journal of Medicine and Science in Sports, 11,
347-354.
Kraemer, W. J., Noble, B. J., Clark, M. J., & Culver, B. W. (1987).
Physiologic responses to heavy-resistance exercise with very
short rest periods. International Journal of Sports Medicine, 8,
247-252.
Kra em er, W. J ., M architelli, L., Gordon, S. E., Harma n, E .,
Dziados, J. E., Mello, R., Frykman, P., McCurry, D., & Fleck,
S. J. (1990). Hormonal and growth factor responses to heavy
resistance exercise protocols. Journal of Applied Physiology,
69, 1442-1450.
Kraemer, W. J., Gordon, S. E., Fleck, S. J., Marchitelli, L. J.,
Mello, R., Dziados, J. E., Friedl, K., Harman, E., Maresh, C., &
Fry, A. C. (1991). Endogenous anabolic hormonal and growth
factor responses to heavy resistance exercise in males and
females. International Journal of Sports Medicine, 12, 228-235.
Kraemer, W. J., Fry, A. C., Warren, B. J., Stone, M. H., Fleck, S.
J., Kearney, J. T., Conroy, B. P., Maresh, C. M., Weseman, C.
A., Triplett, N. T., & Gordon, S. E. (1992). Acute hormonal
responses in elite junior weightlifters. International Journal of
Sports Medicine, 13, 103-109.
Kraemer, W. J., Fleck, S. J., Dziados, J. E., Harman, E. A.,
Marchitelli, L. J., Gordon, S. E., Mello, R., Frykman, P. N.,
Koziris, L. P., & Triplett, N. T. (1993). Changes in hormonal
concentrations after different heavy-resistance exercise
protocols in women. Journal of Applied Physiology, 75,
594-604.
McCall, G. E., Byrnes, W. C., Fleck, S. J., Dickinson, A., &
Kraemer, W. J. (1999). Acute and chronic hormonal responses
to resistance training designed to promote muscle hypertrophy.
Canadian Journal of Applied Physiology, 24, 96-107.
Nygren, A. T., Greitz, D., & Kaijser, L. (2000). Changes in
cross-sectional area in human exercising and non-exercising
skeletal muscles. European Journal of Applied Physiology, 81,
210-213.
Pearlman, W. H., & Crepy, O. (1967). Steroid-protein interaction
with particular reference to testosterone binding by human
serum. Journal of Biological Chemistry, 242, 182-189.
Ploutz-Snyder, L. L., Convertino, V. A., & Dudley, G. A.
(1995). Resistance exercise-induced uid shifts: change in
active muscle size and plasma volume. American Journal of
Physiology, 269, R536-R543.
Raastad, T., Bjoro, T., & Hallen, J. (2000). Hormonal responses
to high- and moderate-intensity strength exercise. European
Journal of Applied Physiology, 82, 121-128.
Stokes, K. A., Nevill, M. E., Hall, G. M., & Lakomy, H. K. (2002).
The time course of the human growth hormone response to a 6
s and 30 s cycle ergometer sprint. Journal of Sports Sciences,
20, 487-494.
Takarada, Y., Nakamura, Y., Aruga, S., Onda, T., Miyazaki, S.,
& Ishii, N. (2000). Rapid increase in plasma growth hormone
after low-intensity resistance exercise with vascular occlusion.
Journal of Applied Physiology, 88, 61-65.
Thuma, J. R., Gilders, R., Verdun, M., & Loucks, A. B. (1995).
International Journal of Sport and Health Science Vol.2, 111-118, 2004
Goto, K., Ishii, N., and Takamatsu, K.
http://wwwsoc.nii.ac.jp/jspe3/index.htm
118
Name:
Kazushige Goto
Af liation:
Institute of Health and Sport Sciences,
University of Tsukuba, Japan Society for
the Promotion of Science
Address:
1-1-1 Tennodai, Tsukuba, Ibaraki 305-8574 Japan
Brief Biographical History:
1999 -Mast er’s Progr am in Heal th and P hysic al Educa tion,
University of Tsukuba
2001-Doctoral Program in Health and Sport Sciences, University
of Tsukuba
2003-Research Fellow of the Japan Society for the Promotion of
Science
Main Works:
"A single set of low intensity resistance exercise immediately
following high intensity resistance exercise stimulates growth
hormone secretion in men." Journal of Sports Medicine and
Physical Fitness 43 (2):243-249, 2003.
"Muscular adaptations to combinations of high-and low-intensity
resistance exercises." Journal of Strength and Conditioning
Research (in press).
Membership in Learned Societies:
• American College of Sports Medicine (ACSM)
• National Strength & Conditioning Association ( NSCA)
• Japan Society of Physical Education
• The Japanese Society of Physical Fitness and Sports Medicine
• Japan Society of Exercise and Sports Physiology
• Japan Society of Training Science for Exercise and Spor t
Circadian rhythm of cortisol confounds cortisol responses to
exercise: implications for future research. Journal of Applied
Physiology, 78, 1657-1664.
M. (1997). Testosterone and cortisol in relationship to dietary
nutrients and resistance exercise. Journal of Applied Physiology,
82, 49-54.
... It is suggested that muscle fatigue increases muscle activation (i.e., increase of electromyographical signal [EMG]) to maintain muscle function during RT (30,40). Considering that there is an association between microvascular oxygenation status and muscle activation with muscle hypertrophy (38,43,44), coaches and practitioners use several training techniques (i.e., RT systems) emphasizing/modulating different RT variables (e.g., volume or load) in order to change the microvascular oxygenation status and increase muscle activation (10,16). Albeit RT systems are widely recommended to modulate these mechanisms related to muscle hypertrophy (39), little is known if these RT systems produce a different microvascular oxygenation status and muscle activation from those observed in traditional RT (TRAD; performed with constant load and repetitions). ...
... Furthermore, the study did not compare the effects of DS with TRAD and assessed only one microvascular oxygenation parameter. Additionally, other studies (15,16) concluded that a protocol that most closely resembles DS (i.e., a set performed until muscle failure after a short pause at the end of the training session) produced higher increases in indirect indicators of metabolic stress (e.g., lactate and growth hormone [GH]) compared with TRAD. Therefore, despite no study compared the effects of DS on microvascular oxygenation with TRAD, it is conceivable that higher volume inherent to DS would produce higher microvascular oxygenation changes compared with TRAD. ...
... Accordingly, the DS protocol used herein produced a greater number of repetitions than TRAD and CP (i.e., TRAD = 30 ± 0 reps; DS = 64 ± 7 reps; CP = 24 ± 0 reps), allowed by the load "drops" after a very short rest resulting in greater TTV (Fig. 3), what may explain the greater changes not only in HHb, but also in HbO2 and HbDiff. In fact, studies (15,16) showed higher increases in indirect indicators of metabolic stress (i.e., lactate and growth hormone [GH]) which are speculated be related to changes on microvascular oxygenation status (38) in a protocol that resembles DS (i.e., additional sub-set to concentric failure after reducing load in the last set, resulting in a higher TTV compared with TRAD). Therefore, we suggest that the specificity of the DS protocol (i.e., large number of repetitions resulting in greater TTV than other tested RT protocols) resulted in higher microvascular oxygenation changes compared with TRAD and CP. ...
Article
Metabolic stress is a primary mechanism of muscle hypertrophy and is associated with microvascular oxygenation and muscle activation. Considering that drop-set (DS) and crescent pyramid (CP) resistance training systems are recommended to modulate these mechanisms related to muscle hypertrophy, we aimed to investigate if these resistance training systems produce a different microvascular oxygenation status and muscle activation from those observed in traditional resistance training (TRAD). Twelve volunteers had their legs randomized in an intra-subject cross-over design in TRAD (3 sets of 10 repetitions at 75% 1-RM), DS (3 sets of ∼50-75% 1-RM) and CP (3 sets of 6-10 repetitions at 75-85% 1-RM). Vastus medialis microvascular oxygenation and muscle activation were respectively assessed by non-invasive near-infrared spectroscopy and surface electromyography techniques during the resistance training sessions in the leg-extension exercise. Total hemoglobin area under the curve (AUC) (TRAD: -1653.5 ± 2866.5; DS: -3069.2 ± 3429.4; CP: -1196.6 ± 2675.3) and tissue oxygen saturation (TRAD: 19283.1 ± 6698.0; DS: 23995.5 ± 15604.9; CP: 16109.1 ± 8553.1) increased without differences between protocols (p>0.05). Greater decreases in oxygenated hemoglobin AUC and hemoglobin differentiated AUC were respectively found for DS (-4036.8 ± 2698.1; -5004.4 ± 2722.9) compared with TRAD (-1951.8 ± 1720.0; -2250.3 ± 1305.7) and CP (-1814.4 ± 2634.3; 2432.2 ± 2891.4) (p<0.03). Higher increases of hemoglobin deoxygenated AUC were found for DS (1426.7 ± 1320.7) compared with TRAD (316.0 ± 1164.9) only (p=0.04). No differences were demonstrated in electromyographic amplitudes between TRAD (69.0 ± 34.4), DS (61.3 ± 26.7) and CP (60.9 ± 38.8) (p>0.05). Despite DS produced lower microvascular oxygenation levels compared with TRAD and CP, all protocols produced similar muscle activation levels.
... A study investigating 13 male participants before, 15 minutes and 30 minutes after leg press exercise reported that the GH concentrations further increased in the higher volume groups with a peak at 15 minutes, while they gradually decreased in the lower volume groups [123]. All studies that employed follow-up measures 60 minutes post-exercise described that peripheral GH decreased towards -or in most cases even below -the resting value [40,45,62,64,65,75,82,95]. ...
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Background: The nervous system integrates the immune system in the systemic effort to maintain or restore the organism's homeostasis. Acute bouts of exercise may alter the activity of specific pathways associated with neuroendocrine regulation of the immune system. Objective: To examine the acute effects of heavy resistance exercise on biomarkers of neuroendocrine-immune regulation in healthy adults. Methods: A systematic literature search was conducted using PubMed, Cochrane Controlled Trials Register, Web of Science and SportDiscus with no date restrictions up to March 2021. Clinical trials in English or German were included if they measured the blood plasma or serum concentrations of specific biomarkers of neuroendocrine-immune regulation (adrenaline, noradrenaline, acetylcholine, vasoactive intestinal peptide (VIP), cortisol, growth hormone, calcitonin gene-related peptide (CGRP), substance p, serotonin, brain-derived neurotrophic factor (BDNF), nerve growth factor (NGF) or glia-derived neurotrophic factor (GDNF)) in a resting state prior to and no later than 60 minutes after an acute bout of heavy resistance exercise in healthy adults. Results: 7801 records were identified through literature search, of which 36 studies, with a total of 58 intervention groups, met the inclusion criteria. Evidence was found that an acute bout of heavy resistance exercise increased the levels of adrenaline (median: 185%), noradrenaline (median: 113%) and GH (median: 265%) immediately after the exercise. Mixed results were found for cortisol (median: 0%), suggesting that its response might be more sensitive to the configuration of the exercise scheme. The limited evidence regarding the effects on BDNF and ACTH allows no firm conclusions to be drawn about their response to heavy resistance exercise. The vast majority of the included studies reported a return of the biomarker concentrations to their baseline value within one hour after the termination of the exercise bout. No studies were identified that investigated the response of acetylcholine, VIP, CGRP, substance p, serotonin, NGF or GDNF to heavy resistance exercise. Conclusions: A bout of heavy resistance exercise alters the circulating concentrations of selected biomarkers of neuroendocrine-immune regulation. Both subject characteristics, such as sex as well as exercise parameters, such as rest intervals appear to have the potential to influence these effects.
... Several studies have investigated the acute hormonal response to advanced training methods. In these studies, forced repetitions and drop set training showed greater post-exercise elevations in growth hormone compared to traditional training (189,190), whereas accentuated eccentric exercise did not (191). However, as previously mentioned, acute systemic elevations do not seem to play much if any role in long-term hypertrophic adaptations (130), making these findings of questionable relevance. ...
Article
Full-text available
Hypertrophy can be operationally defined as an increase in the axial cross-sectional area of a muscle fiber or whole muscle, and is due to increases in the size of pre-existing muscle fibers. Hypertrophy is a desired outcome in many sports. For some athletes, muscular bulk and, conceivably, the accompanying increase in strength/power, are desirable attributes for optimal performance. Moreover, bodybuilders and other physique athletes are judged in part on their muscular size, with placings predicated on the overall magnitude of lean mass. In some cases, even relatively small improvements in hypertrophy might be the difference between winning and losing in competition for these athletes. This position stand of leading experts in the field synthesizes the current body of research to provide guidelines for maximizing skeletal muscle hypertrophy in an athletic population. The recommendations represent a consensus of a consortium of experts in the field, based on the best available current evidence. Specific sections of the paper are devoted to elucidating the constructs of hypertrophy, reconciliation of acute vs long-term evidence, and the relationship between strength and hypertrophy to provide context to our recommendations.
... Medium movement tempo increases time under tension (TUT) during a set, which increases the volume of effort [13]. Higher volume protocols with medium movement tempo and greater metabolic demands lead to increased hormonal responses compared to faster movement tempo [18,19]. Furthermore, the physiological effect of medium movement tempo during resistance exercise can be similar to what occurs during resistance exercise with blood flow restriction [20]. ...
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Background: Resistance training is a significant part of ice-hockey players’ conditioning, where optimal loading should ensure strength development and proper recovery. Therefore, this study aimed to compare the acute physiological responses to fast and medium movement tempo resistance exercises in ice-hockey players. Methods: Fourteen ice-hockey players (26.2 � 4.2 years; 86.4 � 10.2 kg; squat one repetition maximum (1RM) = 130.5 � 18.5) performed five sets of the barbell squat and barbell bench press at 80% 1RM until failure in a crossover design one week apart using either 2/0/2/0 or 6/0/2/0 (eccentric/isometric/concentric/isometric) tempo of movement. The blood samples to evaluate the concentration of cortisol, testosterone, insulin-like growth factor 1 (IGF-1), and growth hormone (hGH) were taken before exercise, 3 min after the last set of the squat exercise, 3 min after the last set of the bench press exercise, and after 30 min of recovery. Results: The 2/0/2/0 tempo resulted in a higher number of repetitions (p < 0.001) and lower time under tension (p < 0.001) in the squat and bench press exercises compared to the 6/0/2/0 movement tempo. The endocrine responses to exercise were significantly higher during the 2/0/2/0 compared to the 6/0/2/0 movement tempo protocol for IGF-1, hGH, and cortisol (p < 0.01). There were no differences in testosterone responses between exercises performed with fast and medium movement tempos. Conclusion: Fast eccentric tempo induced higher cortisol, IGF-1, and hGH responses compared to the medium tempo. Therefore, fast eccentric movement tempo seems to be more useful in eliciting training stimulus than medium eccentric tempo during resistance training in ice-hockey players. However, future studies are needed to confirm our findings.
... The main finding of this study is that the movement tempo did not cause significant differences in the level of the concentrations of the Post-Ex hormones after SQ Goto et al. 2003). These results are consistent with the results obtained in the presented study, where we demonstrated significant Post-Ex increase levels of C, GH, IGF-1, T, compared to Pre-Ex independently for MED and SLO movement tempo. ...
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Objective: The squat exercise is one of the most exhaustive one in which different resistance training methods can elicit various changes in the concentration of many metabolites circulating in the blood. Therefore, the aim of this study is to assess the differences between slow (5/0/3/0) and conventional (2/0/2/0) barbell squat movement tempo to concentric failure on acute metabolites and hormonal responses. Materials and methods: Ten experienced powerlifters (24.3 ± 3.2 y; 77.9 ± 7.2 kg; 141 ± 17.5 kg Squat 1RM) who compete at the national and international level performed five sets of the barbell squat exercise (SQ) to failure at load 80% 1RM with two different tempo of movement: a 2/0/2/0 medium tempo (MED) and a 5/0/3/0 slow tempo (SLO) randomly one week apart. Venous blood samples (10ml) were collected from the antecubital vein, to determine acute pre and post-exercise values of testosterone (T), growth hormone (GH), insulin-like growth factor I (IGF-1), cortisol (C), creatine kinase (CK) and lactate acid (LA). Results: The SLO protocol resulted in higher time under tension (p<0.01) and lower number of performed repetition (p<0.01) than MED protocol. Both exercise protocols test showed high increase of T, C, GH, IGF-1, CK and LA between pre and post exercise (p<0.01). Performing 5 sets of SLO squats resulted in higher post exercise increase of LA (p < 0.03) and CK (p < 0.02) than MED protocol. There were no other significant differences in analysed endocrine variables. Therefore, the SLO exercise tempo elicit higher lactate and muscle damage, but not the acute hormonal response. Conclusion: This study demonstrated that in terms of endocrine response, the optimal moderate exercise tempo result in high endocrine response, which is not dramatically increased by longer time under tension resulting from slow exercise execution. On the other hand, slow speed resulting in longer time under tension cause more muscle damage and lactate production, which may play a large role in stimulating muscle growth and tissue regeneration. PMID: 33315342
... Testosterone. Resistance exercise protocols of high volume (3-6 sets; 8-12 reps), moderate load (60-85% 1RM), and short rest intervals (30-90 seconds), which activate large muscle groups, elicit the greatest acute elevations in testosterone (2,8,12,17,39,68,75,96). However, there are no guidelines regarding the tempo of movement in these recommendations. ...
Article
Wilk, M, Tufano, JJ, and Zajac, A. The influence of movement tempo on acute neuromuscular, hormonal, and mechanical responses to resistance exercise—a mini review. J Strength Cond Res XX(X): 000–000, 2020—Resistance training studies mainly analyze variables such as the type and order of exercise, intensity, number of sets, number of repetitions, and duration and frequency of rest periods. However, one variable that is often overlooked in resistance training research, as well as in practice, is premeditated movement tempo, which can influence a myriad of mechanical and physiological factors associated with training and adaptation. Specifically, this article provides an overview of the available scientific literature and describes how slower tempos negatively affect the 1-repetition maximum, the possible load to be used, and the number of repetitions performed with a given load, while also increasing the total time under tension, which can mediate acute cardiovascular and hormonal responses. As a result, coaches should consider testing maximal strength and the maximal number of repetitions that can be performed with each movement tempo that is to be used during training. Otherwise, programming resistance training using various movement tempos is more of a trial-and-error approach, rather than being evidence or practice based. Furthermore, practical applications are provided to show how movement tempo can be adjusted for a variety of case study–type scenarios.
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To examine endogenous anabolic hormonal responses to two different types of heavy resistance exercise protocols (HREPs), eight male and eight female subjects performed two randomly assigned protocols (i.e. P-1 and P-2) on separate days. Each protocol consisted of eight identically ordered exercises carefully designed to control for load, rest period length, and total work (J) effects. P-1 utilized a 5 RM load, 3-min rest periods and had lower total work than P-2. P-2 utilized a 10 RM load, 1-min rest periods and had a higher total work than P-1. Whole blood lactate and serum glucose, human growth hormone (hGH), testosterone (T), and somatomedin-C [SM-C] (i.e. insulin-like growth factor 1, IGF-1) were determined pre-exercise, mid-exercise (i.e. after 4 of the 8 exercises), and at 0, 5, 15, 30, and 60 min post-exercise. Males demonstrated significant (p less than 0.05) increases above rest in serum T values, and all serum concentrations were greater than corresponding female values. Growth hormone increases in both males and females following the P-2 HREP were significantly greater at all time points than corresponding P-1 values. Females exhibited significantly higher pre-exercise hGH levels compared to males. The P-1 exercise protocol did not result in any hGH increases in females. SM-C demonstrated random significant increases above rest in both males and females in response to both HREPs.(ABSTRACT TRUNCATED AT 250 WORDS)
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To examine endogenous anabolic hormone and growth factor responses to various heavy resistance exercise protocols (HREPs), nine male subjects performed each of six randomly assigned HREPs, which consisted of identically ordered exercises carefully designed to control for load [5 vs. 10 repetitions maximum (RM)], rest period length (1 vs. 3 min), and total work effects. Serum human growth hormone (hGH), testosterone (T), somatomedin-C (SM-C), glucose, and whole blood lactate (HLa) concentrations were determined preexercise, midexercise (i.e., after 4 of 8 exercises), and at 0, 5, 15, 30, 60, 90, and 120 min postexercise. All HREPs produced significant (P less than 0.05) temporal increases in serum T concentrations, although the magnitude and time point of occurrence above resting values varied across HREPs. No differences were observed for T when integrated areas under the curve (AUCs) were compared. Although not all HREPs produced increases in serum hGH, the highest responses were observed consequent to the H10/1 exercise protocol (high total work, 1 min rest, 10-RM load) for both temporal and time integrated (AUC) responses. The pattern of SM-C increases varied among HREPs and did not consistently follow hGH changes. Whereas temporal changes were observed, no integrated time (AUC) differences between exercise protocols occurred. These data indicate that the release patterns (temporal or time integrated) observed are complex functions of the type of HREPs utilized and the physiological mechanisms involved with determining peripheral circulatory concentrations (e.g., clearance rates, transport, receptor binding). All HREPs may not affect muscle and connective tissue growth in the same manner because of possible differences in hormonal and growth factor release.
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The growth-promoting actions of a number of hormones on muscle have been studied by a number of investigators during the past two decades, and some reasonably solid conclusions can now be reached. The somatomedins and insulin are major stimulators of anabolic processes in skeletal muscle; the last remaining uncertainty (absence of evidence that the somatomedins could replace growth hormone in stimulating weight gain in hypophysectomized animals) has recently been removed. The situation with growth hormone is less clear. Evidence from studies on isolated diaphragm muscles is consistent in indicating responsiveness to growth hormone, but most of it was obtained using supraphysiological levels of the hormone, and (in contrast to somatomedin and insulin) it has not been possible to demonstrate direct effects of this hormone on isolated muscle cells. There are some similar problems in the case of insulin—it is not clear to what extent the anabolic actions of insulin can be attributed to its cross-reaction with the somatomedin receptor and/or its effects on energy metabolism, but there is recent convincing evidence that this hormone has direct anabolic effects on muscle cells in culture. The effects of androgens are much more apparent in the whole animal than in isolated muscles or cell culture systems, and they have been more difficult to characterize. The thyroid hormones are clearly required for normal growth and development in the intact animal, but there is not much information on their actions on isolated muscle or cultured cells. Surprisingly, Cortisol exhibits some growth-promoting effects, but these may be attributable to maintenance of the cells in a “healthy” state rather than to a direct stimulation of anabolic processes. In no case is there any detailed biochemical information on the mechanisms by which any of these growth-promoting actions occur, although it is reasonable to infer that the presence of a cytoplasmic receptor for testosterone in muscle indicates a typical steroid-induced activation of RNA synthesis and a resultant increase in protein synthesis. Thus, although a good deal of progress has been made in cataloging the hormones most likely to have direct effects on the growth of muscle, much remains to be done in determining just how those hormones act.
Article
In this study, the difference between the effects of "power-up type" and "bulk-up type" strength training exercise was investigated by analyzing parameters such as structural and functional adaptations in the neuromuscular system. Eleven subjects were divided into power-up and bulk-up groups. The power-up group comprised five male subjects who performed 5 sets at 90% of one repetition maximum (1 RM) with a 3-min rest between sets (repetition method). The bulk-up group comprised six male subjects who performed 9 sets at 80-60-50%, 70-50-40%, and 60-50-40% of 1 RM with rest intervals between sets of either 30 s or 3 min (interval method). Both groups performed isotonic knee extension exercise twice a week for 8 weeks. The power-up group showed a lower rate of improvement than the bulk-up group in terms of cross-sectional area (CSA) of the quadriceps femoris at levels 30% , 50% and 70% from the top of the femur, and also in average isokinetic strength (Isok. ave.; 180 deg/s, 50 consecutive repetitions). However, the power-up group showed a greater rate of improvement in 1 RM, maximal isometric strength (Isom. max), and maximal isokinetic strength (Isok. max ; 60, 180, 300 deg/s). Furthermore, the rate of reduction in strength over 50 consecutive isokinetic repetitions decreased in the bulk-up group. On the other hand, the power-up group showed no significant changes in the above throughout the entire training program. These results indicate that the characteristics of the two types of training exercise are as follows:(1) power-up exercise is effective mainly for improving muscular strength and anaerobic power, and (2) bulk-up exercise is effective mainly for improving hypertrophy and anaerobic endurance. These findings support the idea that "power-up type" and "bulk-up type" strength training exercises should be applied appropriately according to the training aim.
Article
A training experiment was carried out to investigate the difference in training effects between power-up type and bulk-up type strength training exercises from the aspects of muscle histochemical properties and capillary supply. The subjects were eleven healthy males. The power-up type group (five males) performed knee extension exercise for 5 sets at 90% of 1 RM (one repetition maximum) with a 3-min rest between sets (repetition method). The bulk-up type group (six males) performed the same exercise for 9 sets at 80-40% of 1RM with a 30-s or 3-min rest between sets (interval method, multi-poundage system). Both programs were carried out twice a week for 8 weeks. The main results were as follows ; 1. Percentages of fiber types showed no recognizable changes in either group. 2. Fiber area was significantly increased for all fiber types (Type I, Type IIA, Type IIB) in both groups. However, the rate of increase was greatest for type IIA fiber, followed by type IIB fiber and then type I fiber. Moreover, the rate of increase for all fiber types in the bulk-up group was higher than that in the power-up group. 3. Percentage of fiber area showed no recognizable changes for any fiber types in the power-up group. However, the percentage area of type II fibers, especially type IIB fiber, was significantly decreased in the bulk-up group. 4. CC (Type I), CC (Type IIA) and CC (Type IIB) (number of capillaries in contact with each fiber type) were significantly increased in both groups. However, in comparison with CC (Type I). CC (Type IIA · Type HB) showed a higher rate of increase in the power-up group. On the other hand, in comparison with CC (Type IIA · Type IIB), CC (Type I) showed a higher rate of increase in the bulk-up group. Also, compared with the power-up group, the bulk-up group showed a significantly higher rate of increase of CC (Type I). 5. C/Fiber area (Type I), C/Fiber area (Type IIA) and C/Fiber area (Type IIB) (number of capillaries supplying each fiber area) were decreased in both groups. The above results show that power-up type exercise leads mainly to hypertrophy of type I, type IIA and type IIB fibers without any change in percentage fiber type or percentage fiber area, whereas bulk-up type exercise leads mainly to hypertrophy of each fiber type with decreases in percentage area of type II fibers, especially type IIB fiber. Also, power-up type exercise leads mainly to an increase in the number of capillaries around type II fibers, whereas bulk-up type exercise leads mainly to an increase in the number of capillaries around type I fiber. However, capillary development around all fiber types did not necessary coincide with muscle hypertrophy in either exercise. The authors reported previously that power-up type exercise is effective mainly for improving muscular strength and anaerobic power, whereas bulk-up type exercise is effective mainly for inducing hypertrophy and anaerobic endurance. The results of this study may help to clarify these effects from the viewpoint of the adaptations of muscle fibers and the capillary supply.
Article
The first part of this series of articles discussed basic concepts of resistance training; parts 2 and 3 continued with a discussion of physiological responses and adaptations that occur as a result of such training. In this fourth and concluding article, the authors discuss resistance training as exercise prescription and outline the program design process. They point out the importance of making preliminary assessments; defining specific goals and expectations; and evaluating the individual needs, goals, and demands of the participants to help them benefit from the program as much as possible.
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To date, no published studies have demonstrated resistance exercise-induced increases in serum testosterone in adolescent males. Furthermore, few data are available on the effects of training experience and lifting performance on acute hormonal responses to weightlifting in young males. Twenty-eight junior elite male Olympic-style weightlifters (17.3 +/- 1.4 yrs) volunteered for the study. An acute weightlifting exercise protocol using moderate to high intensity loads and low volume, characteristic of many weightlifting training sessions, was examined. The exercise protocol was directed toward the training associated with the snatch lift weightlifting exercise. Blood samples were obtained from a superficial arm vein at 7 a.m. (for baseline measurements), and again at pre-exercise, 5 min post-, and 15 min post-exercise time points for determination of serum testosterone, cortisol, growth hormone, plasma beta-endorphin, and whole blood lactate. The exercise protocol elicited significant (p less than or equal to 0.05) increases in each of the hormones and whole blood lactate compared to pre-exercise measures. While not being significantly older, subsequent analysis revealed that subjects with greater than 2 years training experience exhibited significant exercise-induced increases in serum testosterone from pre-exercise to 5 min post-exercise (16.2 +/- 6.2 to 21.4 +/- 7.9 nmol.l-1), while those with less than or equal to 2 years training showed no significant serum testosterone differences. None of the other hormones or whole blood lactate appear to be influenced by training experience.(ABSTRACT TRUNCATED AT 250 WORDS)
Article
This study investigated the effects of concurrent endurances and low velocity resistance training (LVR) on measures of strength and aerobic endurance. One group (ES) performed concurrent endurance training 3 days a week and LVR training on alternate days, 3 days a week for 12 weeks. The other group (S) performed only LVR training 3 days a week for 12 weeks without any endurance training. Measurements and increases in training volume were made every three weeks in both groups. Group ES exhibited increases in submaximal exercise responses after 3, 9 and 12 weeks (p less than 0.05). Knee extension peak torque and total work as well as cross-sectional area of quadriceps femoris were significantly increased after 6 and 9 weeks of training in both groups. These findings indicate that no significant differences in strength gains were observed between subjects performing concurrent endurance and resistance training or resistance training only. However, the time-course of adaptations between groups was somewhat different.
Article
Heavy-resistance exercise utilizing very short rest periods is commonly used by body builders to prepare for competition. The purpose of this study was to compare the acute responses of this type of heavy-resistance exercise protocol in competitive body builders (BB) and power lifters (PL). Nine male BB and eight PL were matched for age, size and experience. A ten-station heavy-resistance exercise protocol was used. Each subject performed three sets of 10 repetition maximum (RM) with 10-s rest between sets and alternated 30-s and 60-s rest periods between exercises. No differences were observed in total work between the groups, but BB used a significantly (P less than 0.05) higher percentage of their 1 RM in the bench press and leg press exercises. Heart rate, ratings of perceived exertion (RPE), and lactate levels were obtained during the exercise protocol; significant (P less than 0.05) increases were observed above rest for these variables. RPE was significantly correlated with lactate levels (r = 0.84). Plasma epinephrine, norepinephrine, dopamine, cortisol, and lactate levels significantly increased from pre- to 5 min post-exercise. Mean plasma volumes were reduced -16.6 (+/- 3.64)% and -20.6 (+/- 8.32)% following the exercise protocol for BB and PL, respectively. Significant (P less than 0.05) decreases in eosinophil counts were observed following exercise. No significant differences were observed between BB and PL for any of the physiologic responses measured. PL exhibited a higher incidence (100%) of clinical symptoms of dizziness and nausea compared to BB (11.1%).(ABSTRACT TRUNCATED AT 250 WORDS)