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Abstract

The purpose of this study, it has been aimed to examine the effects of zinc supplementation applied with weight trainings on the testosterone levels in sedentary individuals and athletes. Materials and Methods. As methods of work it was selected 40 male, 20 sedentary male and 20 male who do physical exercises regularly, participated in the study. The participants are divided equally into 4 groups. The groups are constituted in that way: 1st Group: Control Group (S), 2nd Group: Sedentary Group which is supplied with Zinc (Z), 3rd Group: Training Group which is supplied with Zinc (ZT) and 4th Group: Athletes’ Group who performs the weight training (T). The total testosterone and free testosterone values of the participants were measured from the blood samples which were drawn from the participants at the beginning and at the end of the 6-week training period. Results. Like results, has been asserted that the total and free testosterone values of the groups which are supplied with Zinc and perform weight training have increased depending on training and supplementation. Conclusion. In conclusion consequently it has been determined that 6-week zinc supplementation and weight training increase the testosterone levels. Accordingly, it may be said that this implementation contributes to the performance
Human. Sport. Medicine
2017, vol. 17, no. 4, pp. 58–63
58
Introduction. Zinc is one of the significant
and fundamental minerals for organisms. Zinc is
the second most common trace element in human
body after iron. It does not accumulate exces-
sively in tissues though it is consistently taken
through nutriment [12]. Although zinc is found in
small quantities in human body, it takes on tasks
with protein in every organ. Zinc has importance
particularly in growth and development, repro-
duction and immune system [3].
Total zinc content in body is approximately
1,5 gram in women while it is 2,5 gram in men
[18]. Zinc moves in and out of the cells through
transport proteins. These transport proteins takes
zinc and protects cells from zinc toxicity and
enables sufficient amount of zinc to be obtained.
Common zinc transporting proteins are ZIP pro-
teins, ZnT4 proteins and metallothionein [19].
While testosterone is produced by main testis
in male, its primary source is the adrenal gland
and ovaries in female. In male, approximately
7 mg testosterone is produced daily under the
control of hormonal feedback [23]. Although tes-
tosterone is swung regularly in young men, it has
been asserted the testosterone levels decrease
with increasing age in male [17].
Testosterone is a steroid-type hormone pro-
duced out of cholesterol. Steroid hormones that
can be produced in adrenal glands, gonads and
placenta play a significant role in the growth,
development and maturation of the brain [5, 20].
In conclusion, it has been demonstrated that
testosterone has regulatory effects in sexuality,
aggression, sleeping control, cognitive functions,
visual spatial skills, endurance and mood in male
[14, 17]. It is known that androgens which have
growth and virilization stimulating effect are
widely used illegally in order to increase the
muscle structure and accordingly the perfor-
mance of the athletes because of their anabolic
effects occurring when its primary therapeutics
usage forms the therapy of hormone replacement
[2]. However, its dosage used in order to develop
muscles and improve performance of the athletes
may be higher than required dosage [10].
Testosterone is a hormone that has effects on
DOI: 10.14529/hsm170407
THE EFFECTS OF THE ZINC SUPPLEMENTATION
AND WEIGHT TRAININGS ON THE TESTOSTERONE LEVELS
V. Çınar1, cinarvedat@hotmail.com, ORCID: 0000-0003-4883-3995,
L.G. Talaghir2, gtalaghir@ugal.ro, ORCID: 0000-0002-3133-9192,
T. Akbulut1, akbuluttaner23@gmail.com, ORCID: 0000-0003-2500-1117,
M. Turgut3, minetrgt@gmail.com, ORCID: 0000-0002-8556-3114,
M. Sarıkaya4, mucahit.sarikaya@hotmail.com
1Firat University, Elazig, Turkey,
2Dunărea de Jos University, Galati, Romania,
3Bartin University, Bartin, Turkey,
4Van Yuzunciyıl University, Van, Turkey
Aim. The purpose of this study, it has been aimed to examine the effects of zinc supplemen-
tation applied with weight trainings on the testosterone levels in sedentary individuals and ath-
letes. Materials and Methods. As methods of work it was selected 40 male, 20 sedentary male
and 20 male who do physical exercises regularly, participated in the study. The participants are
divided equally into 4 groups. The groups are constituted in that way: 1st Group: Control Group (S),
2nd Group: Sedentary Group which is supplied with Zinc (Z), 3rd Group: Training Group which is
supplied with Zinc (ZT) and 4th Group: Athletes’ Group who performs the weight training (T).
The total testosterone and free testosterone values of the participants were measured fro
m
the blood samples which were drawn from the participants at the beginning and at the end of the
6-week training period. Results. Like results, has been asserted that the total and free testoste-
rone values of the groups which are supplied with Zinc and perform weight training have
increased depending on training and supplementation. Conclusion. In conclusion consequently i
t
has been determined that 6-week zinc supplementation and weight training increase the testoste-
rone levels. Accordingly, it may be said that this implementation contributes to the performance.
Keywords: exercise, zinc supplementation, testosterone.
Чунар В., Талагир Л.Г., Акбулут Т., Влияние потребления цинка
Тургут М., Сарукайя М. и силовых тренировок на уровень тестостерона
Человек. Спорт. Медицина
2017. Т. 17, 4. С. 58–63
59
the skeletal muscle. The most prominent effect of
testosterone is the increase in muscle mass and
glycogens concentration. In a study conducted on
that issue, it has been set forth that short term
high-intensity tiring training enables increase in
total testosterone levels of the athletes and this
increase is observed to continue more distinctively
and significantly in cyclists than the football
players. That demonstrates that cyclists may be
affected by the maximal resistance exercises [1].
Similarly, in the study of [22], the male and
female subjects perform 6 sets squat exercises for
10 times in order to identify the muscle andro-
genous and glucocorticoide receptors of the acute
resistance exercises. While free testosterone
levels increase significantly in both genders
through exercises, total testosterone levels in-
crease in only male subjects. The [8] subjects
624 voluntary male ranging in age from 25 to 85
to a short term highly heavy exercises in cycle
ergometer and state that the serum testosterone
levels of the participants are not affected.
In parallel with this information, in this
study it has been aimed to examine the effects of
6-week zinc supplementation applied with weight
trainings on the free and total testosterone levels.
The paper is equal contribution of all authors.
Materials and Methods. The Subjects: 40
healthy male subjects ranging in age from 18 to
22 participate in the study. The subjects are
equally divided into 4 groups. The pre-test and
post-test model is used. The population of the
study comprises of the students of Adıyaman
University who do physical exercises actively in
different branches and the ones who do not do
sports. All of the subjects stay in the dormitory of
Adıyaman University and are liable to the same
diet.
1st Group: Control Group (S)
2nd Group: Sedentary Gorup which is only
supplied with Zinc (Z)
3rd Group: Training Group which is supplied
with Zinc (ZT)
4th Group: Athletes’ Group who performs the
weight training (T)
The 2nd and 3rd group are supplied with zinc
(2,5–3 mg /kg /day) in addition to the normal diet
for 6 weeks. In addition, the 3rd and 4th group per-
form weight training for 90–120 minutes throu-
ghout 6 weeks and the 1st group, the control
group, are not given zinc supplementation and
do not perform weight trainings.
Examination of the Testosterone. The blood
samples are centrifuged at 3000 rpm³ for 10 mi-
nutes and the blood plasma fractionation is done.
The measurement of the plasma parameters is
carried out at the Biochemistry laboratory of Özel
Işıl Kardiyoloji Dalı Merkezi (Private Işıl Cardio-
logy Center) which operates in Diyarbakır.
The analysis of Testosterone level is done through
the Enzymatic Colometric method by using
the scientific brand BT3000 biochemistry auto
analyzer.
The Statistical Analyses. Variance analysis
is used to identify the differences between
the values of the groups obtained through mea-
surements; and the Duncan’s Multiple Range
Test is used to determine in which groups diffe-
rentiations are observed. The comparison of
the groups is done through t-test in order to iden-
tify the differentiations between the values of
the groups obtained through measurements the
statistical analyses are conducted via SPSS 22.0.
Results. When the bodyweight values given
at (Table 1) is examined, it has not been found
any differences between the pre-test and post-test
values of the 1st group (p > 0.05). It is identified
statistically significant differences between the
pre-test and post-test values of the 2nd, 3rd and
4th groups. It has been determined that zinc sup-
plementation and weight training enables indi-
viduals to lose weight (p < 0.05). It is observed
differences between the groups when the weight
loss of the groups is compared with the control
group and other groups (p < 0.05).
The total and free testosterone values of
the groups are given at (Table 2). As the total
testosterone values are considered, it is deter-
mined that values of both training and supple-
mentation groups increase after the implementa-
tion (p < 0.05). When the pre-test and post-test
values are examined, it has been identified statisti-
cally significant differences in zinc supplementa-
tion, exercise, and zinc supplementation + exercise
groups (p < 0.05). Considering the free testoste-
rone values, it has been observed differences be-
tween the pre-test and post-test values and also
the values increase at the end of the implementa-
tion (p < 0.05).
Discussion. In this study which aims to
examine the effects of 6-week zinc supplementa-
tion applied with weight trainings 4 times a week
on the free and total testosterone levels in seden-
tary and athletes, the total testosterone and free
testosterone values of the participants were
measured from the blood samples which were
drawn from the participants at the beginning and
at the end of the 6-week training period. When
Спортивная тренировка
Human. Sport. Medicine
2017, vol. 17, no. 4, pp. 58–63
60
these measurements are compared, it is identified
that zinc supplementation applied with weight
trainings create positive changes in both free and
total testosterone levels. It is confirmed that these
changes are seen in both groups supplied with
zinc and training and zinc supplementation +
training groups.
In a study conducted on a similar issue,
it is asserted that ZMA (a synthesis of zinc, mag-
nesium and B6 vitamin) which is thought to in-
crease the testosterone levels and given to the
individuals doing regular exercises for 8 weeks
have not created any differences in serum free
and total testosterone values of the participants
[9]. It is thought different findings may result
from implementing different training programs
and usage of a combination of supplementation.
In another study in which it has been obtained
findings parallel to ours, [15] examine the effect
of 4-week zinc and selenium supplementation on
the post exhaustion exercise testosterone and
plasma lactate levels in cyclists. In conclusion,
it is determined that total testosterone is higher in
the group supplied with zinc than the values of
the groups supplied with selenium; and free tes-
tosterone levels are higher in the zinc group than
the values of the other groups. They argue that
zinc and selenium supplementation do not create
any change in rested values at the end of 4 weeks.
The [6] has examined the effect of 4-week zinc
supplementation on the thyroid and testosterone
levels in wrestlers. At the end of the study, it has
been determined 4-week zinc supplementation
(3 mg/kg/day) generates significant increases in
rested total and free testosterone levels. In another
study in which similar findings have been ob-
tained, [7] has examined the changes zinc sup-
plementation applied with tiring cycling ergo-
meter exercise create in the thyroid and testoste-
rone levels of the sedentary individuals. At the end
of 4 weeks, it has been found out the zinc sul-
phate supplementation (3 mg/kg/day) increases
the thyroid hormone and free and total testoste-
rone levels in sedentaries after exercises.
In the study which examines the effect of
doing exercises on the testosterone, [16] have
asserted that high-intensity endurance exercises
done in cycling ergometer create significant in-
creases in the levels of testosterone. In another
study which has set forth doing exercises do not
affect the testosterone levels, [5] have examined
the physical, muscular and endocrine responses
arisen 24 hours after the acute weight and ma-
ximal speed exercises. Consequently, it has not
been determined any changes in creatine kinase,
testosterone, cortisol and muscle injury consi-
dering the blood samples drawn from the partici-
pants 24 hours after the acute and high-intensity
exercises done. It is thought that these findings
confronting with our results may arise from
implementing acute exercises. In a study con-
ducted on subject animals, [24] have examined
Table 1
The Age, Height, Weight and Fat Values of the Research Groups
Values Measurement 1st Group (Cont) 2nd Group (Zn) 3rd Group (Tra + Zn) 4th Group Training
Age (year) I. Measurement 20.04 ± 2.20x 21.02 ± 3.10x 20.89 ± 2.06x 20.44 ± 3.02x
Height (cm) II. Measurement 174.52 ± 7.56x 175.40 ± 8.25x 175.08 ± 7.15x 176.02 ± 7.20x
Weight (kg) I. Pre test
II. Posttest
76.60 ± 5.42ax
75.32 ± 6.90ay
75.22 ± 5.70ax
77.71 ± 5.57bx
75.84 ± 5.92ax
78.22 ± 6.12bx
74.63 ± 5.86ax
77.42 ± 6.08bx
Note: a, b; the differences in measurements that carry different letters at the same column are important
(p < 0.05); x, y, z; the differences between the groups that carry different letters at the same line are important
(p < 0.05). I. Measurement: Pre-Supplementation (Pre Test). II. Measurement: Post-Supplementation (Post Test).
Table 2
Total and Free Testosterone Values of the Research Groups
Values Measurements 1st Group (Cont) 2nd Group (Zn) 3rd Group (Tra + Zn) 4th Group Training
Total
Testosterone
(uIU/mL)
I. Pretest
II. Post test
596,20 ± 52ax
605,40 ± 0.88ax 604,30 ± 0.87ax
638,60 ± 0.74by
612,60 ± 0.96ax
654,20 ± 0.92by
616,50 ± 0.90ax
658,30 ± 0.92by
Free
Testosterone
I. Pre test
II. Post test
14,8 ± 3.76ax
14,6 ± 3.70ax
15,7 ± 3.50ax
18,8 ± 4.18by 16,8 ± 4.48ax
22,5 ± 4.36by
16,6 ± 3.44ax
21,3 ± 3.88by
Note: a, b; the differences in measurements that carry different letters at the same column are important
(p < 0.05); x, y, z; the differences between the groups that carry different letters at the same line are important
(p < 0.05). I. Measurement: Pre-Supplementation (Pre Test). II. Measurement: Post-Supplementation (Post Test).
Чунар В., Талагир Л.Г., Акбулут Т., Влияние потребления цинка
Тургут М., Сарукайя М. и силовых тренировок на уровень тестостерона
Человек. Спорт. Медицина
2017. Т. 17, 4. С. 58–63
61
the effects of regular exercises on the blood glu-
cose and testosterone in diabetic rats. They have
determined that moderate exercises implemented
for 9 weeks decrease the blood glucose and en-
hance the testosterone levels. In a study con-
ducted on human subjects, [21] have studied the
serum anabolic and catabolic effects of the acute
exercises performed close to the anaerobic thre-
shold in antrene and sedentary young males.
In conclusion, the cortisol levels of both sedenta-
ry and athlete groups decrease below the basal
level in 24 hours following the exercise. Addi-
tionally, anabolic hormones (testosterone, growth
hormone and insulin-like growth factor-1) have
increased significantly in both groups but particu-
larly in the antrene group. In a similar study,
it has been determined that short-term high-
intensity tiring exercise enables total testosterone
levels of the athletes to increase considerably [1].
Similarly, [13] has examined the serum adipo-
nectin and testosterone concentration of 12-week
endurance training in young obese males. 21 obese
male participants are divided into two groups as
control group and experimental group. At the end
of the study, it has been confirmed that endurance
training implemented 3 times a week for 12 weeks
has increased the serum adiponectin and testoste-
rone concentration. The [11] studied the effect of
increased exercises and decreased caloric intake
on the testosterone levels. They have ascertained
that 12-week aerobic exercise and caloric intake
restriction have increased significantly the serum
testosterone levels.
Conclusions. As a consequence, 6-week
zinc supplementation applied with weight trai-
nings 4 times a week in sedentaries and athletes
has increased the free and total testosterone levels
significantly. Therefore, it may be said the in-
crement of zinc supplementation in human organ-
ism increases the testosterone levels and consti-
tutes positive effects on the physical perfor-
mance.
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Received 17 November 201
7
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УДК 796.015 + 613.2:669.5 DOI: 10.14529/hsm170407
ВЛИЯНИЕ ПОТРЕБЛЕНИЯ ЦИНКА И СИЛОВЫХ ТРЕНИРОВОК
НА УРОВЕНЬ ТЕСТОСТЕРОНА
В. Чунар1, Л.Г. Талагир2, Т. Акбулут1, М. Тургут3, М. Сарукайя4
1Фиратский университет, г. Элязыг, Турция;
2Нижнедунайский университет, г. Галац, Румыния;
3Бартынский университет, г. Бартын, Турция;
4Университет Ван Юзунджул, г. Ван, Турция
Цель. Целью настоящего исследования являлось изучение того, как потребление цин-
ка в сочетании с силовыми тренировками влияет на уровень тестостерона у людей, веду-
щих малоподвижный образ жизни, и у спортсменов. Материалы и методы. В исследова-
нии приняли участие 40 мужчин, 20 из которых вели малоподвижный образ жизни и
20 регулярно занимались физической активностью. Участники были поделены на 4 равные
группы, а именно: группа 1 – контрольная группа (S); группа 2 – участники, ведущие ма-
лоподвижный образ жизни и получающие добавку с содержанием цинка (Z); группа 3
группа спортсменов, занимающихся силовыми тренировками и получающих добавку с со-
держанием цинка (ZT); группа 4 – группа спортсменов, занимающихся силовыми трени-
Чунар В., Талагир Л.Г., Акбулут Т., Влияние потребления цинка
Тургут М., Сарукайя М. и силовых тренировок на уровень тестостерона
Человек. Спорт. Медицина
2017. Т. 17, 4. С. 58–63
63
ровками (T). Уровень общего тестостерона и несвязанного тестостерона измерялся в об-
разцах крови, взятых у участников в начале исследования и шесть недель спустя. Резуль-
таты. Было установлено, что уровень общего и несвязанного тестостерона возрос в груп-
пах, которые получали добавку с содержанием цинка и занимались силовыми тренировками,
в зависимости от потребления цинка и особенностей тренировки. Выводы. Потребление
добавки с содержанием цинка и силовые тренировки на протяжении шести недель ведут к
повышению уровня тестостерона, что, соответственно, оказывает положительный эффект
на результативность.
Ключевые слова: упражнения, потребление цинка, тестостерон.
Чунар Ведат, профессор, доктор наук, факультет спортивной науки, кафедра физической
культуры и спорта, Фиратский университет, г. Элязыг, Турция. E-mail: cinarvedat@hotmail.com.
Талагир Лаурентиу-Габриэль, профессор, доктор наук, факультет физической культуры и
спорта, кафедра одиночных видов спорта и кинезитерапии, Нижнедунайский университет, г. Галац,
Румыния. E-mail: gtalaghir@ugal.ro.
Акбулут Танер, младший научный сотрудник, факультет спортивной науки, кафедра физи-
ческой культуры и спорта, Фиратский университет, г. Элязыг, Турция. E-mail: akbuluttaner23@
gmail.com.
Тургут Мине, младший научный сотрудник, Школа физической культуры и спорта, кафедра
физической культуры и спорта, Бартынский университет, г. Бартын, Турция. E-mail: minetrgt@
gmail.com.
Сарукайя Мюджахит, младший научный сотрудник, Школа физической культуры и спорта,
кафедра физической культуры и спорта, Университет Ван Юзунджул, г. Ван, Турция. E-mail:
mucahit.sarikaya@hotmail.com.
Поступила в редакцию 17 ноября 2017 г.
ОБРАЗЕЦ ЦИТИРОВАНИЯ FOR CITATION
The Effects of the Zinc Supplementation and Weight
Trainings on the Testosterone Levels / V. Çınar, L.G. Ta-
laghir, T. Akbulut et al. // Человек. Спорт. Медицина. –
2017. – Т. 17, 4. – С. 58–63. DOI: 10.14529/hsm170407
Çınar V., Talaghir L.G., Akbulut T., Turgut M.,
Sarıkaya M. The Effects of the Zinc Supplementation and
Weight Trainings on the Testosterone Levels. Human.
Sport. Medicine, 2017, vol. 17, no. 4, pp. 58–63. DOI:
10.14529/hsm170407
... The performance of Pelung chickens is controlled by testosterone, and good performance is highly important in improving the quality of the cocks. The aromatase enzyme can change the testosterone in chickens into estradiol, and consequently, high testosterone levels cannot be maintained [5]. ...
... The administration of aromatase blocker letrozole (lz; 1.5 mg/kg) can increase testosterone content and improve the reproduction performance of cocks after their peak age [11]. The supplementation of Zn at doses of 2.5-3 mg/kg/day for 6 weeks and weight exercise 4 times a week can significantly increase free and total testosterone content and positively impact human physical performance [5]. The administration of aromatase blocker Taxadrol can increase testosterone content [12]. ...
... According to Astuti et al. [14], the Zn contained in the powder of A. granosa shells could play an important role as an aromatase blocker, which subsequently results in the absence of changes of testosterone into estrogen, such that blood testosterone content is consistently high. Some studies have shown that Zn, Mg, and vitamins in shellfish can increase testosterone content [5]. Supplementation with Zn can increase testosterone content in male rats [17]. ...
Article
Full-text available
Background and aim: Pelung chickens make unique, pleasant, and rhythmic sounds in addition to having strong muscle mass. Performance is controlled by testosterone. A natural aromatase blocker is an agent capable of blocking the aromatase enzyme, which consequently prevents testosterone from being changed into estradiol. Such a condition results in consistently high testosterone levels. The aim of this study was to determine the effect of the administration of the shell powder of Anadara granosa on the testosterone level, frequency and quality of sounds, and metabolism of Pelung chickens within set parameters of thyroid hormone levels, the triiodothyronine (T3)/thyroxine (T4) ratio, and weight gain. Materials and methods: This study used four Pelung chickens aged 14 months. Control data consisted of data before treatment (day 0). Shell powder of A. granosa was administered for 56 days. Body weight (BW) was measured, and blood samples were drawn. In addition, the sounds from Pelung chickens were recorded once every 2 weeks on days 14, 28, 42, and 56. The blood samples were analyzed using the enzyme immunoassay method to determine testosterone, T3, and T4 levels. The sounds of Pelung chickens were recorded using the Hagemon touch method and analyzed using the Audacity application. Results: The results showed a significant difference (p<0.05) in the levels of testosterone, BW, and sound frequency after the administration of A. granosa shell powder, but the administration did not have a significant effect on the levels of T4 and T3 hormones (thyroid hormone), T3/T4 ratio, or sound duration. The testosterone content and BW of Pelung chickens increased from day 14 to day 56, whereas T3 was indicative of the same profile as the T4 hormone. However, T3 and T4 levels and the T3/T4 ratio decreased and increased, respectively. The sound frequency of Pelung chickens increased from day 0 to day 14, although sound duration decreased. Conclusion: The administration of A. granosa shell powder at 0.9 mg/kg BW orally could improve the metabolism, testosterone level, BW, and sound frequency of Pelung chickens.
... Changes in zinc content in prostate tissues are also linked to changes in testosterone metabolism. Zinc is regarded as an androgen modulator [27]. It takes part in regulation of the transformation of testosterone into the biologically active compound 5α-dihydrotestosterone by 5α-reductase. ...
... It takes part in regulation of the transformation of testosterone into the biologically active compound 5α-dihydrotestosterone by 5α-reductase. The dihydrotestosterone-cytoplasmic receptor complex is transported to the prostate cell Nutrients 2021, 13, 100 3 of 27 nucleus, where it induces RNA transcription and synthesis of receptor and secretory proteins of the prostate [27][28][29]. Due to the major role of zinc in prostate cells, it has been suggested that dietary supplementation with zinc can be used in the prevention and treatment of prostate cancer [30]. On the other hand, results on the effectiveness of zinc supplementation can be largely dependent on the dose and duration of supplementation [30,31]. ...
... The working conditions of the spectrometer were optimized daily in order to obtain the maximal sensitivity and stability as well as the lowest level of oxides and double-charged ions ( Table 3). 24 Mg, 27 Al, 39 K, 43 Ca, 51 V, 55 Mn, 57 Fe, 59 Co, 63 Cu, 60 Ni, 66 Zn, 78 Se, 88 Sr, 95 Mo, 111 Cd, 208 Pb ...
Article
Full-text available
Prostate cancer (PCa) is the second most frequent cancer in men and the fifth most common cause of death worldwide, with an estimated 378,553 deaths in 2020. Prostate cancer shows a strong tendency to form metastatic foci in the bones. A number of interactions between cancer cells attacking bones and cells of the bone matrix lead to destruction of the bone and growth of the tumour. The last few decades have seen increased interest in the precise role of minerals in human health and disease. Tumour cells accumulate various minerals that promote their intensive growth. Bone, as a storehouse of elements, can be a valuable source of them for the growing tumour. There are also reports suggesting that the presence of some tumours, e.g., of the breast, can adversely affect bone structure even in the absence of metastasis to this organ. This paper presents the effect of chronic dietary intake of calcium, iron and zinc, administered in doses corresponding maximally to twice their level in a standard diet, on homeostasis of selected elements (Ca, K, Zn, Fe, Cu, Sr, Ni, Co, Mn and Mo) in the femoral bones of healthy rats and rats with implanted cancer cells of the LNCaP line. The experiment was conducted over 90 days. After the adaptation period, the animals were randomly divided into four dietary groups: standard diet and supplementation with Zn, Fe and Ca. Every dietary group was divided into experimental group (with implanted cancer cells) and control group (without implanted cancer cells). The cancer cells (LnCaP) were implanted intraperitoneally in the amount 1 × 106 to the rats at day 90 of their lifetime. Bone tissue was dried and treated with microwave-assisted mineral digestation. Total elemental content was quantified by ICP-MS. Student’s t-test and Anova or Kruskal–Wallis tests were applied in order to compare treatment and dietary groups. In the case of most of the diets, especially the standard diet, the femoral bones of rats with implanted LNCaP cells showed a clear downward trend in the content of the elements tested, which may be indicative of slow osteolysis taking place in the bone tissue. In the group of rats receiving the standard diet, there were significant reductions in the content of Mo (by 83%), Ca (25%), Co (22%), Mn (13%), K (13%) and Sr (9%) in the bone tissue of rats with implanted LNCaP cells in comparison with the control group receiving the same diet but without LNCaP implantation. Supplementation of the rat diet with calcium, zinc and iron decreased the frequency of these changes relative to the standard diet, which may indicate that the diet had an inhibitory effect on bone resorption in conditions of LNCaP implantation. The principal component analysis (PCA) score plot confirms the pronounced effect of implanted LNCaP cells and the standard diet on bone composition. At the same time, supplementation with calcium, zinc and iron seems to improve bone composition. The microelements that most often underwent quantitative changes in the experimental conditions were cobalt, manganese and molybdenum.
... Testosterone concentration also impacts sexual behavior, [14] reported that libido characteristics and testosterone concentration have a positive correlation. This is reinforced [15] that a higher concentration of testosterone, is in line with higher libido. However, the concentration of testosterone fluctuates in the body suitable to the mechanism of feedback of LH hormone through the pituitary and GnRH through the hypothalamus [16]. ...
Article
Full-text available
The hormone testosterone is essential in various biological processes, including reproductive function so its presence in the body must remain stable. Low concentrations of testosterone can affect secondary traits and libido in male animals. Testosterone concentrations are usually increased through hormonal induction, but this will harm long-term administration. The alternative offered in this problem is to give aromatase blockers both in the form of commercial drug injection (letrozole) and natural ingredients (shell powder). Aromatase blockers can inhibit the synthesis of estrogen from testosterone at certain doses that are usually different for each animal, administering aromatase blockers has been shown to increase testosterone concentration, in birds and chickens the administration of aromatase blockers did not have any significant side effects.
... Furthermore strength is an important component for performance. Strength training affects some parameters that related to health as well as performance [6,7]. ...
Article
Full-text available
Aim. The objective of this study is to investigate the effectiveness of Crossfit training in order to minimize performance loss of elite wrestlers during 30-day rest period. Materials and Methods. Total 23 elite male wrestlers who competed at the last national championship participated in this study. The participants were divided into two groups as Crossfit and control group. The Crossfit group performed 5 pull-ups, 10 push-ups and 15 squat exercises consecutively (Crossfit-Cindy) for total 20-min, during the 30-day period, 6 days per week. The Control group did not perform any exercise programs during this period. Before and after the 30-day period, athletes were applied anthropometric measurements as well as VO2max (aerobic capacity), bench press and squat (maximal dynamic strength), leg and handgrip strength (isometric strength), pull-up and push-up (strength endurance) tests. Results. After the 30-day period in the control group, body weight and body fat percentage (BF %) increased significantly, whereas all performance variables decreased significantly. Maximal dynamic strength and aerobic capacity values decreased significantly in the Crossfit group, while body weight, body fat percentage, isometric strength and strength endurance values were maintained. Moreover, the decrease in VO2max and bench press tests was higher in the control group than in the Crossfit group. Conclusion: Consequently, the present study showed that 20-min Crossfit training was highly effective in maintaining the form of elite wrestlers during a 30-day rest period
... Zn has also been shown to affect the anabolic hormone testosterone (T) in some, but not all, studies. Cinar et al. [162] demonstrated that high-dose Zn (2.5-3 mg·kg·day 1 ) appeared to increase post-exercise bound and free T (3.1 pg·dL 1 ). However, six weeks of resistance training with and without Zn induced greater changes (~5.7 pg·dL 1 ,~4.7 pg·dL 1 , respectively) compared to no change in the control group (no Zn or training). ...
Article
Full-text available
Minerals and trace elements (MTEs) are micronutrients involved in hundreds of biological processes. Deficiency in MTEs can negatively affect athletic performance. Approximately 50% of athletes have reported consuming some form of micronutrient supplement; however, there is limited data confirming their efficacy for improving performance. The aim of this study was to systematically review the role of MTEs in exercise and athletic performance. Six electronic databases and grey literature sources (MEDLINE; EMBASE; CINAHL and SportDISCUS; Web of Science and clinicaltrials.gov) were searched, in accordance with PRISMA guidelines. Results: 17,433 articles were identified and 130 experiments from 128 studies were included. Retrieved articles included Iron (n = 29), Calcium (n = 11), Magnesium, (n = 22), Phosphate (n = 17), Zinc (n = 9), Sodium (n = 15), Boron (n = 4), Selenium (n = 5), Chromium (n = 12) and multi-mineral articles (n = 5). No relevant articles were identified for Copper, Manganese, Iodine, Nickel, Fluoride or Cobalt. Only Iron and Magnesium included articles of sufficient quality to be assigned as 'strong'. Currently, there is little evidence to support the use of MTE supplementation to improve physiological markers of athletic performance, with the possible exception of Iron (in particular, biological situations) and Magnesium as these currently have the strongest quality evidence. Regardless, some MTEs may possess the potential to improve athletic performance, but more high quality research is required before support for these MTEs can be given. PROSPERO preregistered (CRD42018090502).
Article
Full-text available
The aim of this research is to evaluate the effect of Anadara granosa shell powder as a natural aromatase blocker (NAB) and zinc sulfate (ZnSO4) on the growth of the length comb, width comb, and body weight (BW) of layer chicken. This study used 45 DOC of layer’s chickens with 3 treatments and 15 replications, those are; control (T0), clamshell powder Anadara granosa as NAB 0.036 mg/40 g BW (T1), and ZnSO 4 0.018 mg / 40 g BW (T2). This treatment was given for 35 days. The data on the growth of length comb, width comb, and BW are measured weekly. The data collected was analyzed using one-way ANOVA at the 95% confidence level with the assistance of SPSS. The results of statistical analysis of the length and width of the comb in the same column showed that T0 was not significantly different (p>0.05) from other treatments. The statistical analysis shows that the length and width of the layer’s chicken comb in the same row at T0, T1 and T2 were significantly different (p<0.05). The results of statistical analysis of the BW in the same column showed that T1 was significantly different (p<0.05) from other treatments. It can be concluded that additional NAB 0.036 mg/40 g BW can increase the body weight of male layer chicken after treatment of 35 days. The administration of NAB and ZnSO 4 could not increase the growth of the length and width of layer chicken combs. The growth in length and width of layer chicken combs is very fast in the starter phase.
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The aim of this study was to investigate the effects of eight weeks exercise program on some hematological parameters in obese and overweight children. A total of 44 boys aged 14-16 were included in the study. The obese group was divided into two groups as 22, and overweight group 22. Body mass index (BMI) values were used to determine obesity in the formation of groups. The children who participated in the study were selected activities according to the branches which lasted 60 minutes in 3 days a week for 3 weeks and the walking program was increased. Blood samples taken at rest and at the end of the study; WBC (leukocyte), RBC (erythrocyte), hemoglobin (HGB), hematocrit (HCT), platelet (PLT), mean platelet volume (MPV) and platelet distribution width (PDW) levels were analyzed. SPSS 22.0 statistical program (SPSS Inc., Chicago, Illinois, USA) was used for the statistical analysis of the data. Independent Samples T test for comparison of binary groups; Paired Samples T tests were used to analyze the difference between pre-test and post-test groups. At the end of the exercise, statistically significant differences were found in body weight, MCV, MPV and PDW values between the pre-test and post-test of the measured values of obese subjects (p <0.05). The body weight, BMI, RBC, HGB, HCT, MPV and PDW values of the overweight group were statistically significant (p<0.05). There was no significant difference between the groups in obese and overweight groups (p>0.05). As a result, it can be said that the obese and overweight group caused changes in hematological parameters and the overweight group was more likely to be affected by the exercise than the obese group.
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Objectives: Athletes are often required to undertake multiple training sessions on the same day with these sessions needing to be sequenced correctly to allow the athlete to maximize the responses of each session. We examined the acute effect of strength and speed training sequence on neuromuscular, endocrine, and physiological responses over 24h. Design: 15 academy rugby union players completed this randomized crossover study. Methods: Players performed a weight training session followed 2h later by a speed training session (weights speed) and on a separate day reversed the order (speed weights). Countermovement jumps, perceived muscle soreness, and blood samples were collected immediately prior, immediately post, and 24h post-sessions one and two respectively. Jumps were analyzed for power, jump height, rate of force development, and velocity. Blood was analyzed for testosterone, cortisol, lactate and creatine kinase. Results: There were no differences between countermovement jump variables at any of the post-training time points (p>0.05). Likewise, creatine kinase, testosterone, cortisol, and muscle soreness were unaffected by session order (p>0.05). However, 10m sprint time was significantly faster (mean±standard deviation; speed weights 1.80±0.11s versus weights speed 1.76±0.08s; p>0.05) when speed was sequenced second. Lactate levels were significantly higher immediately post-speed sessions versus weight training sessions at both time points (p<0.05). Conclusions: The sequencing of strength and speed training does not affect the neuromuscular, endocrine, and physiological recovery over 24h. However, speed may be enhanced when performed as the second session.
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Background: Circulating levels of adiponectin and testosterone decrease in obese men and this increases risks of cardiovascular disease and diabetes. Objectives: The purpose of this study was to survey changes of serum adiponectin and testosterone concentrations following twelve weeks resistance training in obese young men. Patients and methods: In a semi-experimental study, twenty one obese young men were randomly placed in two groups: resistance training (26.5 ± 2.8 years) and control (27.4 ± 2.9 years). General characteristics of subjects and serum levels of adiponectin and testosterone were assessed before and after training. Resistance training protocol consisted of twelve weeks weight training (3 sessions per week, 10 exercises, 3 sets of 8 - 12 repetitions in each exercise, intensity 60% - 80% of one repetition maximum, rest between sets 1 minute and between exercises 2 minutes, duration of main training 20 - 40 minutes per each session). Results: Resistance training had no significant effect on body weight and body mass index (P > 0.05), whereas it decreased body fat percent (P = 0.017). Also, serum adiponectin (8.1 ± 1.8 vs. 10.5 ± 2.3 μg/mL) and testosterone concentrations (6.9 ± 2.4 vs. 8.2 ± 1.7 ng/mL) were increased after resistance training (P = 0.033, P = 0.018 respectively), while there were no significant changes in serum levels of these hormones in control group (P > 0.05). Conclusions: Twelve weeks of resistance training increased serum concentrations of adiponectin and testosterone in obese young men. With respect to inverse associations between changes of adiponectin and testosterone with BFP and insulin level variations after resistance training, it is recommended that obese young men do resistance training to benefit useful decreasing/preventive effects of this type of training against the risks of cardiovascular diseases and diabetes.
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To investigate whether the administration of the zinc-containing nutritional supplement ZMA causes an increase of serum testosterone levels, which is an often claimed effect in advertising for such products; to monitor the urinary excretion of testosterone and selected steroid hormone metabolites to detect potential changes in the excretion patterns of ZMA users. Fourteen healthy, regularly exercising men aged 22-33 years with a baseline zinc intake between 11.9 and 23.2 mg day(-1) prior to the study. Supplementation of ZMA significantly increased serum zinc (P=0.031) and urinary zinc excretion (P=0.035). Urinary pH (P=0.011) and urine flow (P=0.045) were also elevated in the subjects using ZMA. No significant changes in serum total and serum free testosterone were observed in response to ZMA use. Also, the urinary excretion pattern of testosterone metabolites was not significantly altered in ZMA users. The present data suggest that the use of ZMA has no significant effects regarding serum testosterone levels and the metabolism of testosterone in subjects who consume a zinc-sufficient diet.
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The Handbook of Nutrition in Ophthalmology is the first general text on nutrition and eye health created for physicians, nutritionists, and researchers. Dr. Richard D. Semba provides important links between the epidemic of obesity and implications it has for eye disease and blindness. The volume addresses three broad themes throughout. The first is that a healthy diet as a major lifelong habit will likely have an impact on reducing a substantial portion of visual impairment and blindness. The second is that a historical perspective is essential to understanding current challenges in ophthalmology, medicine, and public health. The third theme is that many nutrients play a role in oxidative stress and inflammation, and this theory has emerged as a major underlying hypothesis in the pathogenesis of eye diseases. The volume also includes chapters addressing nutritional aspects of preventing eye disease in diabetes mellitus and other optical neuropathies, making the Handbook of Nutrition in Ophthalmology a unique book for a broad spectrum of physicians and practitioners.
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Platelet-derived growth factor (PDGF)-, epidermal growth factor (EGF)- and insulin-like growth factor I (IGF-I)-stimulated cell proliferation in 3T3 cells was accompanied by increased abundance of labile intracellular pool of zinc (LIPZ). However, the origin and regulation of this cell proliferation-associated increase in the abundance of LIPZ are unknown. Cellular zinc homeostasis involves zinc transporters and metallothionein. The objectives of this study were to determine whether cell proliferation-associated increase in the abundance of LIPZ was a result of an increased zinc uptake and to assess the involvement of zinc transporters and metallothionein in this cell proliferation-associated increase in the abundance of LIPZ in 3T3 fibroblasts. Zinc transporters assessed included both zinc importer (Zip1) and zinc exporters (ZnT1, ZnT2 and ZnT4). Growth factors increased the abundance of LIPZ while total cellular zinc concentration remained unaffected, demonstrating that LIPZ was responsive to the increased needs for zinc during growth factor-stimulated cell proliferation. Growth factors also increased net zinc retention as indicated by higher 65zinc radioactivity and elevated mRNA levels of Zip1, ZnT1 and ZnT4. Although zinc is essential to cell proliferation, excessive cellular zinc accumulation causes cytotoxicity. Collectively, these observations suggest that increase in the abundance of LIPZ during growth factor-stimulated cell proliferation was due to increased net retention of extracellular zinc, which was apparently achieved through a coordinated up-regulation of the expression of transporters involved in both zinc influx and efflux to ensure adequate supply of zinc to sustain cell proliferation, yet to prevent potential zinc cytotoxicity in 3T3 cells.
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The present study aims to investigate how exhaustion exercise affects thyroid hormones and testosterone levels in elite athletes who are supplemented with oral zinc sulfate for 4 weeks. The study included 10 male wrestlers, who had been licensed wrestlers for at least 6 years. Mean age of the wrestlers who volunteered in the study was 18.70 +/- 2.4 years. All subjects were supplemented with oral zinc sulfate (3 mg/kg/day) for 4 weeks in addition to their normal diet. Thyroid hormone and testosterone levels of all subjects were determined as resting and exhaustion before and after zinc supplementation. Resting TT3, TT4, FT3, FT4 and TSH levels of subjects were higher than the parameters measured after exhaustion exercise before zinc supplementation (p<0.05). Both resting and exhaustion TT3, TT4 and FT3 values after 4-week zinc supplementation were found significantly higher than both of the parameters (resting and exhaustion) measured before zinc supplementation (p<0.05). Resting total testosterone and free testosterone levels before zinc supplementation were significantly higher than exhaustion levels before zinc supplementation (p<0.05). Both resting and exhaustion total and free testosterone levels following 4-week zinc supplementation were found significantly higher than the levels (both resting and exhaustion) measured before zinc supplementation (p<0.05). Findings of our study demonstrate that exhaustion exercise led to a significant inhibition of both thyroid hormones and testosterone concentrations, but that 4-week zinc supplementation prevented this inhibition in wrestlers. In conclusion, physiological doses of zinc administration may benefit performance.