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Background The aim of the present study was to analyse the effects of placebo on bench throw performance in Paralympic weightlifting athletes. Methods The study involved four Paralympic weightlifting male athletes (age: 40.25 ± 9.91 years, weight: 60.5 ± 8.29 kg, height: 1.60 ± 0.15 m) that visited the laboratory in three occasions, separated by 72 h. In the first session, the athletes were tested for bench press one repetition maximum (1RM). The other two sessions were performed in a randomized counter-balanced order and involved bench throw tests performed either after taking placebo while being informed that the capsule contained caffeine or without taking any substance (control). The bench throw tests were performed with loads corresponding to 50, 60, 70 and 80% of the bench press 1RM. Results According to the results, mean velocity (∆: 0.08 m/s, ES 0.36, p < 0.05) and mean propulsive velocity (∆: 0.11 m/s, ES 0.49, p < 0.05) at 50% of 1RM were significantly higher during placebo than control (p < 0.05). However, there were no difference between control and placebo for 60, 70 and 80% of 1RM (p > 0.05). Conclusion Our results suggest that placebo intake, when the athletes were informed they were taking caffeine, might be an efficient strategy to improve the performance of explosive movements in Paralympic weightlifting athletes when using low-loads. This brings the possibility of using placebo in order to increase performance, which might reduce the risks associated with ergogenic aids, such as side-effects and positive doping testing.
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R E S E A R C H A R T I C L E Open Access
Effects of placebo on bench throw
performance of Paralympic weightlifting
athletes: a pilot study
Gustavo De Conti Teixeira Costa
, Luan Galvão
, Martim Bottaro
, João Felipe Mota
Gustavo Duarte Pimentel
and Paulo Gentil
Background: The aim of the present study was to analyse the effects of placebo on bench throw performance in
Paralympic weightlifting athletes.
Methods: The study involved four Paralympic weightlifting male athletes (age: 40.25 ± 9.91 years, weight:
60.5 ± 8.29 kg, height: 1.60 ± 0.15 m) that visited the laboratory in three occasions, separated by 72 h. In the
first session, the athletes were tested for bench press one repetition maximum (1RM). The other two sessions were
performed in a randomized counter-balanced order and involved bench throw tests performed either after taking
placebo while being informed that the capsule contained caffeine or without taking any substance (control). The
bench throw tests were performed with loads corresponding to 50, 60, 70 and 80% of the bench press 1RM.
Results: According to the results, mean velocity (Δ: 0.08 m/s, ES 0.36, p< 0.05) and mean propulsive velocity
(Δ:0.11m/s,ES0.49,p< 0.05) at 50% of 1RM were significantly higher during placebo than control (p<0.05).
However, there were no difference between control and placebo for 60, 70 and 80% of 1RM (p>0.05).
Conclusion: Our results suggest that placebo intake, when the athletes were informed they were taking caffeine,
might be an efficient strategy to improve the performance of explosive movements in Paralympic weightlifting
athletes when using low-loads. This brings the possibility of using placebo in order to increase performance, which
might reduce the risks associated with ergogenic aids, such as side-effects and positive doping testing.
Keywords: Nutritional supplements, Sports performance, Psyching up
The intake of nutritional supplements are a common
practice among physical activity practitioners and
athletes; however, few actually have scientific evidence
for their efficacy [1]. Among them, caffeine is one of the
most consumed substances by athletes [2] and is consid-
ered to positively impact physical performance [3]. In
this regard, previous studies suggested that caffeine may
be ergogenic, sparing muscle glycogen improving pain
tolerance, reducing rate of perceived exertion, increase
maximum voluntary contraction, strength and power in
high-intensity activities besides of stimulating central
nervous system [410]. However, there are specific
controversies about its effects, mainly when the studies
compared the acute effects of caffeine vs placebo intake
showed inconsistent conclusions [1117].
While genetic factors might explain a large portion of
the variance associated with the caffeine effects such as
pain tolerance, anxiogenic and alert effects [1820],
there are important psychological responses to ingesting
a substance that should be considered. The placebo
effect [21] can influence the physiological aspects to
physical exercise performance [3]
one of the all factors
that might influence the effects of caffeine is the placebo
effect [22]. In agreement with this, Saunders et al. [23]
found an improvement in the cycling time to exhaustion
in trained cyclists who ingested placebo believing to
have ingested caffeine. Similarly, in a previous study,
* Correspondence:
Faculdade de Educação Física e Dança, Universidade Federal de Goiás,
Goiás, Brazil
Full list of author information is available at the end of the article
© The Author(s). 2019 Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0
International License (, which permits unrestricted use, distribution, and
reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to
the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver
( applies to the data made available in this article, unless otherwise stated.
Costa et al. Journal of the International Society of Sports Nutrition (2019) 16:9
Beedie et al. [24] reported that when competitive male
cyclists ingested placebo believing to have ingested caf-
feine there were increases in aerobic power at VO2max
test and 10-km time trials, with no difference in oxygen
uptake, heart rate, and blood lactate. Such placebo ef-
fects do not rule out a true effect of caffeine supplemen-
tation. Although these studies suggested that aerobic
performance improves following placebo intake when in-
dividuals believed that they are ingesting caffeine, we are
not aware of studies that measured the placebo effect in
powerlifting. Moreover, Paralympic athletes have been
shown to have psychological particularities that might
make them especially vulnerable to the placebo effect,
such as, concerns about having to perform consistently
well throughout training and difficulties in coping with
negative results [25]. Therefore, it seems important to
perform specific studies in these group despite the diffi-
culty to select subjects with these characteristics.
The analysis of the placebo effect might be of great
practical importance since it could provide an alternative
for improving performance through the intake of an
inert substance, with no risk of testing positive for dop-
ing or adverse effects, either due to the direct use of pro-
hibited substances, or by the possible contamination of
nutritional supplements [10,2630]. Based on this, the
present study aimed to evaluate if muscle performance
during explosive movements would change in Paralympic
weightlifting athletes after the intake of placebo when the
participants were informed that they were taking caffeine.
Materials and methods
Four Paralympic weightlifting male athletes were
recruited to participate in this study (age: 40.25 ± 9.91 y,
weight: 60.5 ± 8.29 kg, height: 1.60 ± 0.15 m). One had
dwarfism, one myelomeningocele and hydrocephalus
and two poliomyelitis. Athletes trained regularly five
times a week aiming to compete, and all had previous
experience with caffeine use, but have not taken any
caffeine supplements in the previous six months. Two
athletes had won medals in at least two phases on the
national circuit. They were only allowed to participate if
they had no orthopaedic or cardiometabolic problems
that could be aggravated by the study protocol, as
attested by a physician. This study was approved by
Federal University of Goias committee (2.058.322) and
all the participants signed a written informed consent
form before participation (Table 1).
The study is a randomized, double-blind, crossover
study. The athletes attended the laboratory three times,
with an interval of 72 h between visits. During the first
visit, they were submitted to the one repetition
maximum test (1RM) in the bench press, as previously
recommended [31]. The second and third visits involved
the bench throw tests. The athletes were randomly
assigned to ingest a capsule of placebo or no capsule on
the second and third visits, in a cross-over design.
During the placebo situations, the athletes received one
capsule containing maize starch one-hour prior the test
and were informed that it contained 6 caffeine.
The athletes were oriented to avoid caffeine containing
beverages and foods one week prior to the beginning of
the study.
Data collection
Muscular performance was measured in the bench
throw, using an isoinertial indicator (T-Force, Dynamic
Measurement System; Ergotech Consulting S.L., Murcia,
Spain). The exercise was performed on a smith machine
and the athletes were instructed to perform three repeti-
tions with maximum intended velocity in all repetitions.
The tests were performed with 50, 60, 70 and 80% of
1RM, with 5 min of rest between each load condition.
The movement started with elbows fully extended and
then the bar was get down until touching the sternum.
A linear position transducer was attached to the bar.
The bar position data were sampled at 1000 Hz using a
computer, as recommended by the manufacturer. The
finite differentiation technique was used to calculate the
velocity and acceleration of the bar, presenting an
associated error of < 0.25%, while the displacement was
accurate to ±0.5 mm [32].
Statistical analysis
Data were analysed using the Statistical Package of
Social Science software (SPSS 20.0, Chicago, IL, USA).
Factorial ANOVA with a within-within design was used
to compare the performance between placebo vs control
situation at different loads. When necessary multiple
comparisons were used as post hoc. Data were consid-
ered statistically significant when p< 0.05. Effect size
(ES) of the mean differences was determined using
Cohens d. The magnitude of the ES was determined by
Hopkins scale as follows: < 0.1 (trivial), 0.10.3 (small),
0.30.5 (moderate), 0.50.7 (large), 0.70.9 (very large)
and > 0.9 (perfect) [33].
Table 1 Characteristics of the participants
Mean Minimum Maximum
Age (years) 40.25 ± 9.91 26 54
Weight (kg) 60.6 ± 8.36 49.0 71.2
Height (m) 1.61 ± 0.16 1.36 1.78
Body mass index (kg/m
) 23.83 ± 4.48 19.38 30.82
1 repetition maximum load (kg) 69 ± 19.46 40 92
Costa et al. Journal of the International Society of Sports Nutrition (2019) 16:9 Page 2 of 6
Tabl e 2shows the results relative to the absolute velocity
values as a function of the load lifted. Although the mean
velocity to peak and peak velocity were not different be-
tween situations, the mean velocity at 50% RM was signifi-
cantly higher in placebo vs control (Δ: 0.08 m/s), with
moderate effect size (0.36; p< 0.05). Similarly, mean
propulsive velocity at 50% RM was significantly higher in
placebo vs. control (Δ: 0.11 m/s) with moderate effect size
(0.49; p< 0.05) as shown in Fig. 1.
To the best of our knowledge, this was the first study to
analyse the placebo effects of caffeine on bench throw
performance of Paralympic weightlifting athletes. Accord-
ing to the results, the ingestion of placebo significantly
increases mean velocity and mean propulsive velocity at
50% of 1RM. These findings may be particularly interest-
ing, since this intensity is in the recommend range for
maximum power output in the bench throw [34].
Moreover, considering that the tests involved highly trained
athletes, the differences might be relevant to training and
competition. It is important to note that, whilst they did
not reach significance, the differences with higher loads oc-
curred in the opposite direction, with a trend for a detri-
mental effect with placebo. The reason for this is not
known, but there are two hypotheses to consider. First, the
tests were incremental, so it might be possible that the
higher performance in the earlier sets with lower loads lead
to fatigue in the later sets, performed with higher loads.
Second, when the load increased and becomes more chal-
lenging, the participants might have expected to have an
improved performance perform. However, since there was
not physiologic enhancement due to the supplementation,
a negative psychological influence might have occurred.
Although the deception used in the present study is
not common in scientific literature, it is closer to what
happens in real world, where many athletes take nutri-
tional supplements believing on a true physiological
effect, which might affect the results [22]. Besides that,
uptake placebo was able to improve performance on
bench throw with no reports of adverse effects already
shown to caffeine supplementation before [10]. In this
regard, Hurst et al. suggested that the intention to im-
prove performance by the athletes when taking placebo
can make a difference in the final performance; there-
fore, in order to take full advantage of this intervention,
the athletes should believe in the benefits of the ingested
substance [35].
Whilst many athletes believe that nutritional supple-
ments are related to performance enhancements [36]
most do not obtain adequate information and do not
even know the active ingredients or mechanism of
action of the substances used [3642]. Therefore,
supplements use seems to rely more on beliefs than on
scientific evidence. Considering our findings that an
inert substance might increase performance when
athletes were deceived to believe it was an ergogenic aid;
this might help to explain the divergence that often
occurs between anecdotal and scientific evidence. On
the other hand, this study had the focus only in placebo
effect and a third group of caffeine was not used aiming
to compare three groups.
Regarding the possible explanation for the placebo
effect, Beedie et al. divided it in four categories: pain
reduction, belief-behaviour relation, attentional changes
and arousal changes. Within these mechanisms, the
improvements found in our study can be explained by
attentional and arousal changes [24]. Besides that, caf-
feine intake also increasing pain tolerance [43], however,
this probably did not happen in this study due to short
duration with just three repetitions of exercise per-
formed. The placebo effect might be associated with
self-directed cognitive strategies and preparatory arousal
(i.e. including imagery and attentional focus), which has
been shown to enhance force production [44,45].
The major limitation of the present study is the low
number of participants. However, due to the characteristics
Table 2 Comparison between the placebo and control group on velocity of displacement of the bar in bench press
Variable 50% 1RM ES 60% 1RM ES 70% 1RM ES 80% 1RM ES
Mean velocity (m/s) Control 0.76 ± 0.08 0.36* 0.70 ± 0.07 0.19 0.61 ± 0.10 0.26 0.47 ± 0.10 0.31
Placebo 0.84 ± 0.12 0.74 ± 0.12 0.56 ± 0.08 0.41 ± 0.08
Mean velocity to peak (m/s) Control 0.79 ± 0.09 0.33 0.72 ± 0.07 0.18 0.61 ± 0.11 0.19 0.48 ± 0.10 0.31
Placebo 0.87 ± 0.13 0.76 ± 0.13 0.57 ± 0.09 0.42 ± 0.08
Mean propulsive velocity (m/s) Control 0.81 ± 0.09 0.46* 0.74 ± 0.09 0.19 0.63 ± 0.12 0.27 0.48 ± 0.10 0.36
Placebo 0.92 ± 0.12 0.79 ± 0.15 0.57 ± 0.09 0.41 ± 0.08
Peak velocity (m/s) Control 1.16 ± 0.11 0.37 1.06 ± 0.13 0.14 0.91 ± 0.19 0.27 0.72 ± 0.19 0.32
Placebo 1.27 ± 0.16 1.11 ± 0.21 0.82 ± 0.11 0.61 ± 0.12
ES effect size, RM Repetition Maximum
*significant difference between placebo and control (p< 0,05)
Costa et al. Journal of the International Society of Sports Nutrition (2019) 16:9 Page 3 of 6
of the participants, it would be difficult to obtain a higher
sample size. It would also be interesting to have a third
situation, with caffeine use. Future research should be con-
ducted on a higher number of athletes, including Paralym-
pic athletes with different limitations. Moreover, it would
be valuable to assess the long-term effects of placebo, in
order to test if the regular increase in performance over
training sessions might bring long-term benefits.
Our results suggest that placebo intake, when the
athletes believe they are taking caffeine, might be an
efficient strategy to improve performance in the bench
throw test in Paralympic weightlifting athletes under
low-loads. This brings the possibility of using placebo in
order to increase performance in plyometric and speed
exercises, reducing the side effects and risks associated
with the use of ergogenic aids. Additionally, it would be
ideal that nutritional strategy was investigated with high
loads before using it in practice. Finally, it might be
suggested that part of the conflict that usually exists be-
tween anecdotal reports and scientific evidence about
nutritional supplementation can be associated to the
psychological effects of ingesting a supplement.
Authors would like to thank to subjects that participated of this study for
their commitment and effort.
This research received no grant.
Availability of data and materials
The datasets used and analyzed during the current study are available from
the corresponding author on reasonable request.
GC participated in the study design, collected data, interpreted the data, and
wrote the article. GC, LG, MB, JFM, GDP, and PG participated in the study
design, and wrote the manuscript. All authors read and approved the final
Ethics approval and consent to participate
Participation in the study was voluntary, with written consent being
obtained from each subject before the initiation of data collection. This
study was conducted after review and approval by the Federal University of
Goias committee. Committees reference number: 2.058.322.
Consent for publication
All the study participants gave their consent to publish the research findings.
Competing interests
The authors declare that they have no competing interests.
Springer Nature remains neutral with regard to jurisdictional claims in
published maps and institutional affiliations.
Author details
Faculdade de Educação Física e Dança, Universidade Federal de Goiás,
Goiás, Brazil.
Faculdade de Educação Física, Universidade de Brasília, Distrito
Federal, Brasília, Brazil.
Faculdade de Nutrição, Universidade Federal de
Goiás, Goiás, Brazil.
Fig. 1 Mean propulsive velocity (m/s)
Costa et al. Journal of the International Society of Sports Nutrition (2019) 16:9 Page 4 of 6
Received: 13 July 2018 Accepted: 12 February 2019
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Costa et al. Journal of the International Society of Sports Nutrition (2019) 16:9 Page 6 of 6
... Três estudos usaram uma célula de carga para determinar a força muscular em SUP (Costa et al., 2019;Dos Santos et al., 2020;Sampaio et al., 2020). Dois estudos de Araujo Mendonça, Fernandes, Orrico & Queiroz, 2020) usaram um sensor de força para determinar o índice de fadiga, força isométrica máxima e taxa de desenvolvimento de força. ...
... Um estudo (Dos utilizaram um paquímetro antropométrico para mensurar a distância bilateral entre os processos acromiais de cada atleta e assim verificar diferentes larguras de pegada com a realização do SUP. Por outro lado, um estudo (Costa et al., 2019) observaram como o efeito placebo poderia influenciar no desempenho de atletas e nesse sentido, outro estudo (Sampaio et al., 2020) verificaram como a ingestão de creatina influenciou o desempenho, razão pela qual usaram placebo em um grupo amostral. Por fim, um estudo analisou padrões dermatoglíficos por meio de impressões digitais para avaliar a predisposição genética de atletas (Figueira et al., 2012). ...
... No estudo incluído em nossa investigação, os autores (Costa et al., 2019) examinaram o efeito da ingesta de placebo de amido de milho com cafeína, no exercício supino, em diferentes concentrações de carga. Para isso, os atletas visitaram o laboratório três vezes, com intervalo de 72 horas entre cada visita. ...
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RESUMO O objetivo desta pesquisa é apontar os estudos que descrevem variáveis que se associam a um impacto positivo no desempenho competitivo em atletas de para powerlifting. Para desenvolver o estudo foi utilizada as diretrizes Preferred Reporting Items for Systematic Reviews e Meta-Analyses Extension for Scoping Reviews (PRISMA-ScR) e os estudos foram extraídos de bases de dados eletrônicas como Web of Science, PubMed, Scopus, ScienceDirect e EBSCO. Foi realizado um processo de seleção por título, resumo e texto completo, de acordo com os critérios de inclusão e exclusão. Inicialmente foram identificados 154 estudos que após a eliminação de duplicatas e aplicação dos critérios de inclusão, foram selecionados 8 artigos originais para análise qualitativa. Os resultados indicam que existem fatores fisiológicos e biomecânicos relacionados ao desempenho esportivo. A ingestão de placebo, uso de monohidrato de creatina, percentual de massa magra, predisposição genética e diversos métodos de recuperação de curto e médio prazo, como agulhamento seco e imersão em água fria, são fatores fisiológicos relacionados ao desempenho. Em relação aos fatores biomecânicos, foi evidenciado que a mensuração da preensão da barra se relaciona com maior produção de força e velocidade propulsora média.
... In this regard, Pollo et al. (2008) reported a significant increase in leg extension strength and a decrease in perceived fatigue when providing an ergogenic placebo. Similarly, Costa et al. (2019) observed that placebo provision was effective in improving bench press throw performance in Paralympic weightlifters. Moreover, performance in repeated 30-m sprints did not differ significantly between baseline and experimental trials when subjects believe in the effectiveness of a placebo treatment (Beedie et al., 2007). ...
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Although cold water immersion (CWI) is one of the most widely used post-exercise strategies to accelerate recovery processes, the benefits of CWI may be associated with placebo effects. This study aimed to compare the effects of CWI and placebo interventions on time course of recovery after the Loughborough Intermittent Shuttle Test (LIST). In a randomized, counterbalanced, crossover study, twelve semi-professional soccer players (age 21.1 ± 2.2 years, body mass 72.4 ± 5.9 kg, height 174.9 ± 4.6 cm, V ˙ O2max 56.1 ± 2.3 mL/min/kg) completed the LIST followed by CWI (15 min at 11°C), placebo (recovery Pla beverage), and passive recovery (Rest) over three different weeks. Creatine kinase (CK), C-reactive protein (CRP), uric acid (UA), delayed onset muscle soreness (DOMS), squat jump (SJ), countermovement jump (CMJ), 10-m sprint (10 mS), 20-m sprint (20 mS) and repeated sprint ability (RSA) were assessed at baseline and 24 and 48 h after the LIST. Compared to baseline, CK concentration was higher at 24 h in all conditions (p < 0.01), while CRP was higher at 24 h only in CWI and Rest conditions (p < 0.01). UA was higher for Rest condition at 24 and 48 h compared to Pla and CWI conditions (p < 0.001). DOMS score was higher for Rest condition at 24 h compared to CWI and Pla conditions (p = 0.001), and only to Pla condition at 48 h (p = 0.017). SJ and CMJ performances decreased significantly after the LIST in Rest condition (24 h: −7.24%, p = 0.001 and −5.45%, p = 0.003 respectively; 48 h: −9.19%, p < 0.001 and −5.70% p = 0.002 respectively) but not in CWI and Pla conditions. 10 mS and RSA performance were lower for Pla at 24 h compared to CWI and Rest conditions (p < 0.05), while no significant change was observed for 20 mS time. These data suggests that CWI and Pla intervention were more effective than the Rest conditions in recovery kinetics of muscle damage markers and physical performance. Furthermore, the effectiveness of CWI would be explained, at least in part, by the placebo effect.
... A sample data size of 13 subjects per intervention group was estimated (each subject participates in the three intervention groups). Due to the lack of athletes competing at this level, and the COVID-19 pandemic, analysis was carried out with a sample size lower than estimated, including six participants, this number previously being used in a variety of studies with Paralympic athletes [22,42]. ...
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Throughout history a variety of therapeutic tools have been studied as possible enhancers of sports activities. This study proposes the use of Capacitive-Resistive Electric Transfer (CRET) as a performance booster to paralympic athletes, specifically those belonging to the Spanish Paralympic swimming committee. The study was a randomized, single-blind, and observer-blind, crossover clinical trial. Six athletes were randomly assigned to three groups: one treated with CRET (A); a placebo group (B) and a control group (C). The CRET group attended a twenty-minute session before being subjected to pool trials at distances of 50 and 100 m at maximum performance. Measurements were in two dimensions: time in seconds and the Borg scale for perceived exertion. Comparisons between groups were made with respect to distance and the main variables. In the case of perceived exertion, no significant changes were observed in any of the distances; however, in the case of the time variable, a significant difference was observed between Group A vs. Personal Record at 100 m distance (76.3 ± 6.8 vs. 68.4 ± 3.3). The proposed protocol and level of hyperthermia applied suggest refusal of CRET use for the 100-m distance a few minutes before sports practice. Our analysis suggests the need to modify the presented protocol. identifier under NCT number: NCT04336007.
... Thus, 17 full-text articles were read. Nine studies were excluded, most commonly because they did not provide isolated caffeine supplementation or did not evaluate ballistic throwing performance [23][24][25][26][27][28][29][30][31]. As a result, nine articles [11][12][13][14][15][17][18][19][20] were found to satisfy the inclusion criteria in the primary search. ...
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Ballistic exercise is characterized by high velocity, force, and muscle activation. Typical examples of ballistic exercise are jumping and throwing activities. While several studies explored caffeine's effects on throwing performance, the between study findings varied. Therefore, we performed a meta-analysis exploring caffeine's effects on throwing performance (e.g., shot put, medicine ball throw, bench press throw). Seven databases were searched for eligible research. Ten studies (n = 151) were included. In the main meta-analysis, there was a significant ergogenic effect of caffeine on throwing performance (standardized mean difference [SMD]: 0.19; 95% confidence interval [CI]: 0.05, 0.33; p = 0.007). There was a significant ergogenic effect of caffeine in the subgroup analysis for studies that evaluated throwing velocity (SMD: 0.24; 95% CI: 0.10, 0.37; p = 0.0006) and used caffeine doses ≤3 mg/kg (SMD: 0.18; 95% CI: 0.05, 0.31; p = 0.006). There was no significant difference between caffeine and placebo in the subgroup analysis for studies that evaluated throwing distance (SMD: 0.15; 95% CI: −0.09, 0.40; p = 0.22) and used caffeine doses >3 mg/kg, (SMD: 0.17; 95% CI: −0.08, 0.41; p = 0.19). However, after one outlier study was excluded as part of a sensitivity analysis, an ergogenic effect was also observed for throwing distance and caffeine doses >3 mg/kg. Based on the results of this review, we conclude that individuals interested in the acute enhancement of throwing performance may consider caffeine supplementation.
... Regarding the variables of maximum velocity and mean propulsive velocity, it is noticeable a greater slowness in carrying out the lifting of the bar in the higher relative loads. The same trend occurred in the study [26] when comparing the velocity-load during bench press relationship in athletes performing the movement with the back in a natural lumbar arch and moderate scapular retraction vs. the back with a lumbar arch pronounced and scapular retraction and, in the study [27] when analyzing the velocity of displacement of the bar in the bench press in a tied vs. untied condition. ...
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The bench press is performed in parapowerlifting with the back, shoulders, buttocks, legs and heels extended over the bench, and the use of straps to secure the athlete to the bench is optional. Thus, the study evaluated muscle activation, surface electromyography (sEMG), maximum velocity (MaxV) and mean propulsive velocity (MPV), and power in paralympic powerlifting athletes under conditions tied or untied to the bench. Fifteen experienced Paralympic powerlifting male athletes (22.27 ± 10.30 years, 78.5 ± 21.6 kg) took part in the research. The sEMG measurement was performed in the sternal portion of the pectoralis major (PMES), anterior deltoid (AD), long head of the triceps brachii (TRI) and clavicular portion of the pectoralis major (PMCL). The MaxV, MPV and power were evaluated using an encoder. Loads of 40%, 60%, 80% and 100% 1RM were analyzed under untied and tied conditions. No differences were found in muscle activation between the tied and untied conditions; however, sEMG showed differences in the untied condition between AD and TRI (F (3112) = 4.484; p = 0.005) in the 100% 1RM load, between PMCL and AD (F (3112) = 3.743; p = 0.013) in 60% 1RM load and in the tied condition, between the PMES and the AD (F (3112) = 4.067; p = 0.009). There were differences in MaxV (F (3112) = 213.3; p < 0.001), and MPV (F (3112) = 248.2; p < 0.001), between all loads in the tied and untied condition. In power, the load of 100% 1RM differed from all other relative loads (F (3112) = 36.54; p < 0.001) in both conditions. The tied condition seems to favor muscle activation, sEMG, and velocity over the untied condition.
... Previous studies have used relative loads to assess kinetics and kinematics in supine exercise [8]. In the study by Costa et al. [9], the mean velocity, mean propulsive velocity, and mean peak velocity were greater at 50% 1 RM when compared to 60%, 70%, and 80% 1 RM. Furthermore, relative loads of 25 to 45% of 1 RM have been good parameter settings for the assessment of training velocity and movement patterns in supine [10]. ...
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(1) Background: Paralympic Powerlifting (PP) is a Paralympic modality that is predominantly about developing maximal force, as there are athletes who lift three times their body weight. Our objective was to evaluate the averages of the velocity for 30% and 50% of 1 Maximum Repetition (1 RM) on different amplitudes of the footprint in PP athletes; (2) Methods: The intervention happened over two weeks, with the first being devoted to the familiarization and testing of 1 RM, while in the second week, through the use of a linear Encoder, tests of velocity average (VA), velocity average propulsive (VAP), and velocity peak (VP) were carried out with loads of 30% and 50% of a maximum repetition 1 RM for 1× of the biacromial distance (BAD) 1.3 × BAD, 1.5 × BAD; (3) Results: There was a significant difference in the average velocity of 1 × BAD (1.16 ± 0.14 m/s, 1.07–1.26 IC; η2p 0.20) when compared to 1.3 × BAD (1.00 ± 0.17 m/s, 0.90–1.09 IC; η2p 0.20) over 30% of 1 RM. For the other velocity variables for 30% and 50% of 1 RM with different grip amplitudes, there were no significant differences; (4) Conclusions: In PP, the 1 × BAD footprint contributes significantly to VA at 30% of 1 RM when compared to the 1.3 × BAD and 1.5 × BAD footprints. For loading at 50% of 1 RM the VA, VAP and VP decreased when compared to 30% of 1 RM, to the extent that the VAP and VP generated with the 1.3 × BAD and 1.5 × BAD footprints were higher than those with 1 × BAD, other than for VA 50% of 1 RM, where the 1 × BAD footprint was superior to the others.
Bench press training seems to be the most common exercise for increasing upper-body strength and control among athletes, fitness enthusiasts, and wellness buffs. Bench presses are usually done by lying down on the bench with the back, shoulders, and buttocks in touch. The bench press training surveillance systems with technical advancements are rarely seen in the research domain. Therefore, this paper presents a novel bench press training monitoring method (BPTMM) by evaluating mechanical joint rotational friction using Internet of Things (IoT) sensors. The bench press is a common upper body strength-building and muscle-building conditioning exercise. The bench press and the squat and deadlift are the three primary lifts performed in powerlifting competitions. Artificial intelligence aids in risk prediction and suggests possible positions. There is a 96.8% accuracy rate in surveillance and categorization, according to the findings of the experiments.
The present study aimed to validate the perceived exertion scale based on the repetitions in reserve (RIR) of Paralympic Powerlifting (PP) athletes. Twenty-one PP athletes were assessed in the one-maximum repetition test (1RM) of the bench press exercise, maximum repetition strength tests with loads corresponding to 90%, 85%, 80%, and 75% of 1RM, and 4-repetitions strength tests (4-repST) with 100%, 90%, 85%, 80%, and 75% of the 1RM. The RIR scale was assessed after each set of the 4-repST and compared to the 1RM and maximum strength tests. For criterion validity, the total estimated repetition was significantly lower compared to the maximum strength test repetitions in the lower scores of the RIR scale (median=7.0 vs. 9.0 for 75% of 1RM). The total estimated repetition correlation with maximum strength was very high and significant (ICC=0.91). Using the Bland and Altman method, the difference between means was 0.9 reps, and the interval around differences was 6.4 reps. For construct validity, and the RIR scale presented high correlation with 1RM intensities (rho=0.86, p≤0.05). The RIR scale was validated and coaches and sports trainers can use this monitoring tool to ensure submaximal loads when improving lift technique, which is extremely rigorous in PP.
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In the last few years, a plethora of studies explored the effects of caffeine on resistance exercise, demonstrating that this field of research is growing fast. This review evaluated and summarized the most recent findings. Given that toxic doses of caffeine are needed to increase skeletal muscle contractility, the binding of caffeine to adenosine receptors is likely the primary mechanism for caffeine’s ergogenic effects on resistance exercise. There is convincing evidence that caffeine ingestion is ergogenic for: (i) one-repetition maximum, isometric, and isokinetic strength; and (ii) muscular endurance, velocity, and power in different resistance exercises, loads, and set protocols. Furthermore, there is some evidence that caffeine supplementation also may enhance adaptations to resistance training, such as gains in strength and power. Caffeine ingestion is ergogenic for resistance exercise performance in females, and the magnitude of these effects seems to be similar to those observed in men. Habitual caffeine intake and polymorphisms within CYP1A2 and ADORA2A do not seem to modulate caffeine’s ergogenic effects on resistance exercise. Consuming lower doses of caffeine (e.g., 2 to 3 mg/kg) appears to be comparably ergogenic as consuming high doses of caffeine (e.g., 6 mg/kg). Minimal effective doses of caffeine seem to be around 1.5 mg/kg. Alternate caffeine sources such as caffeinated chewing gum, gel, and coffee are also ergogenic for resistance exercise performance. With caffeine capsules, the optimal timing of ingestion seems to be 30 to 60 minutes pre-exercise. Caffeinated chewing gums and gels may enhance resistance exercise performance even when consumed 10 minutes before exercise. It appears that caffeine improves performance in resistance exercise primarily due to its physiological effects. Nevertheless, a small portion of the ergogenic effect of caffeine seems to be placebo-driven.
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This study aimed to determine if belief in caffeine's ergogenic potential influences choice reaction time (CRT) and/or running performance. Twenty‐nine healthy individuals (23.7 ± 5 years, 16 males) completed two trials (one week apart). Before the trials, participants indicated their “belief” in caffeine's ergogenic effects and previous “experience” using caffeine for performance. On arrival, participants randomly received either sham “Low (100mg; LD)” or “High (300mg; HD)” dose caffeine capsules 30‐min before commencing the CRT test, followed by a 10km run. Paired samples t‐tests determined differences between trials for CRT latency (Ex‐Gaussian analysis; μ‐, σ‐ and τ‐) and running performance using the entire cohort and sub‐groups exhibiting strong “beliefs”+/−“experience”. Sham caffeine dose did not influence CRT (μ‐, σ‐ and τ‐respectively, LD: 400 ± 53ms vs. HD: 388 ± 41ms; LD: 35 ± 18ms vs. HD: 34 ± 17ms; LD: 50 ± 24ms vs. HD: 52 ± 19ms, all p's > 0.05). Neither belief (n = 6), nor belief + experience (n = 4), influenced this effect. Furthermore, caffeine dose did not influence run time (LD: 49.05 ± 3.75min vs. HD: 49.06 ± 3.85min, p = 0.979). Belief (n = 9) (LD: 48.93 ± 3.71min vs. HD: 48.9 ± 3.52min, p = 0.976), and belief + experience (n = 6) (LD: 48.68 ± 1.87min vs. HD: 49.55 ± 1.75min, p = 0.386) didn't influence this effect. A dose‐response to sham caffeine ingestion was not evident on cognitive or endurance performance in healthy individuals, regardless of their convictions about caffeine's ergogenicity.
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Caffeine used as a supplement has been shown to improve physical and cognitive performance in several sport modalities due to its effects on the central nervous system. This review assesses the direct effects of caffeine supplementation on performance in combat sports. Using the PRISMA (Preferred Reporting Items for Systematic Review and Meta-Analysis) guidelines, relevant studies were identified through the Medline, Scopus and SPORTDiscus databases. Of 1053 search results, only 9 articles fulfilled the inclusion criteria. Of these, three studies detected no ergogenic effect of caffeine supplementation, while six studies did observe a significant positive effect. Supplementation with 3–6 mg/kg of caffeine was found to increase the glycolytic contribution to energy metabolism during the execution of real or simulated combats, as indicated by elevated blood lactate concentrations. Caffeine intake was also noted to improve levels of strength, power and upper arm muscular endurance. These effects were not paralleled by an increase in the exertion perceived by the athlete.
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Nutrition usually makes a small but potentially valuable contribution to successful performance in elite athletes, and dietary supplements can make a minor contribution to this nutrition programme. Nonetheless, supplement use is widespread at all levels of sport. Products described as supplements target different issues, including (1) the management of micronutrient deficiencies, (2) supply of convenient forms of energy and macronutrients, and (3) provision of direct benefits to performance or (4) indirect benefits such as supporting intense training regimens. The appropriate use of some supplements can benefit the athlete, but others may harm the athlete’s health, performance, and/or livelihood and reputation (if an antidoping rule violation results). A complete nutritional assessment should be undertaken before decisions regarding supplement use are made. Supplements claiming to directly or indirectly enhance performance are typically the largest group of products marketed to athletes, but only a few (including caffeine, creatine, specific buffering agents and nitrate) have good evidence of benefits. However, responses are affected by the scenario of use and may vary widely between individuals because of factors that include genetics, the microbiome and habitual diet. Supplements intended to enhance performance should be thoroughly trialled in training or simulated competition before being used in competition. Inadvertent ingestion of substances prohibited under the antidoping codes that govern elite sport is a known risk of taking some supplements. Protection of the athlete’s health and awareness of the potential for harm must be paramount; expert professional opinion and assistance is strongly advised before an athlete embarks on supplement use.
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Studies show mixed results for the effects of caffeine on performance, warranting further investigation. The purpose of this study was to examine the acute effects of a caffeine-containing supplement on anaerobic power and subjective measurements of fatigue during resisted sprinting on males. Fourteen recreationally-active males [N=14; (mean±SD), age: 21.0±0.7 yrs., height: 178.5±5.1 cm, weight: 77.3±9.6 kg, percent body fat: 12.6±4.8%] participated in a double-blind, placebo controlled, within-subjects crossover design study. The first visit required each participant to complete three sets of practice sprints on a non-motorized treadmill ranging from 10-20 seconds. During the second visit, participants completed five more practice sprints ranging from 15-25 seconds. During the third and fourth visits, participants ingested one serving of a caffeine-containing or placebo beverage (the opposite beverage was consumed during the fourth visit), rested for 20-minutes, and completed a dynamic warm-up prior to sprinting. Anaerobic power was assessed using a counter-movement vertical jump and non-motorized treadmill sprint test. Psychological variables were scored using a 5-point Likert scale. No significant (p<0.05) differences were observed between conditions for average (p=0.22) or peak power (p=0.43). Both conditions resulted in a significant increase in fatigue, though the increase was less for the caffeine condition (caffeine [INCREMENT]=0.93; placebo [INCREMENT]=1.71). These findings indicated that the caffeine-containing supplement improved perceived measures of fatigue but not power indices assessed through vertical jump or non-motorized treadmill sprinting. The consumption of a caffeine beverage may be beneficial for reducing perceived fatigue during acute anaerobic exercise, particularly when repeated sprints are utilized.
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The aim of this study was to determine the effect of caffeine intake on overall basketball performance in experienced players. A double-blind, placebo-controlled, randomized experimental design was used for this investigation. In two different sessions separated by one week, 20 experienced basketball players ingested 3 mg of caffeine/kg of body mass or a placebo. After 60 min, participants performed 10 repetitions of the following sequence: Abalakov jump, Change-of-Direction and Acceleration Test (CODAT) and two free throws. Later, heart rate, body impacts and game statistics were recorded during a 20-min simulated basketball game. In comparison to the placebo, the ingestion of caffeine increased mean jump height (37.3 ± 6.8 vs. 38.2 ± 7.4 cm; p = 0.012), but did not change mean time in the CODAT test or accuracy in free throws. During the simulated game, caffeine increased the number of body impacts (396 ± 43 vs. 410 ± 41 impacts/min; p < 0.001) without modifying mean or peak heart rate. Caffeine also increased the performance index rating (7.2 ± 8.6 vs. 10.6 ± 7.1; p = 0.037) during the game. Nevertheless, players showed a higher prevalence of insomnia (19.0 vs. 54.4%; p = 0.041) after the game. Three mg of caffeine per kg of body mass could be an effective ergogenic substance to increase physical performance and overall success in experienced basketball players.
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Introduction: The use of dietary supplements is increasing among athletes, year after year. Related to the high rates of use, unintentional doping occurs. Unintentional doping refers to positive anti-doping tests due to the use of any supplement containing unlisted substances banned by anti-doping regulations and organizations, such as the World Anti-Doping Agency (WADA). The objective of this review is to summarize the presence of unlabeled doping substances in dietary supplements that are used in sports. Methodology: A review of substances/metabolites/markers banned by WADA in ergonutritional supplements was completed using PubMed. The inclusion criteria were studies published up until September 2017, which analyzed the content of substances, metabolites and markers banned by WADA. Results: 446 studies were identified, 23 of which fulfilled all the inclusion criteria. In most of the studies, the purpose was to identify doping substances in dietary supplements. Discussion: Substances prohibited by WADA were found in most of the supplements analyzed in this review. Some of them were prohormones and/or stimulants. With rates of contamination between 12 and 58%, non-intentional doping is a point to take into account before establishing a supplementation program. Athletes and coaches must be aware of the problems related to the use of any contaminated supplement and should pay special attention before choosing a supplement, informing themselves fully and confirming the guarantees offered by the supplement.
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Although a large body of evidence exists documenting the ergogenic properties of caffeine, most studies have focused on endurance performance. However, findings from endurance sports cannot be generalized to performance in ball games where, apart from having a high level of endurance, successful athletic performances require a combination of physiological, technical and cognitive capabilities. The purpose of this review was to critically evaluate studies that have examined the effect of a single dose of caffeine in isolation on one or more of the following performance measures: total distance, sprint performance, agility, vertical jump performance and accuracy in ball games. Searches of three major databases resulted in 19 studies (invasion games: 13; net-barrier games: 6) that evaluated the acute effects of caffeine on human participants, provided the caffeine dose administered, and included a ball games specific task or simulated match. Improvements in sprint performance were observed in 8 of 10 studies (80%), and vertical jump in 7 of 8 studies (88%). Equivocal results were reported for distance covered, agility and accuracy. Minor side effects were reported in 4 of 19 studies reviewed. Pre-exercise caffeine ingestion between 3.0 and 6.0 mg/kg of body mass appears to be a safe ergogenic aid for athletes in ball games. However, the efficacy of caffeine varies depending on various factors, including, but not limited to, the nature of the game, physical status and caffeine habituation. More research is warranted to clarify the effects of caffeine on performance measures unique to ball games, such as agility and accuracy. It is essential that athletes, coaches and practitioners evaluate the risk-benefit ratio of caffeine ingestion strategies on an individual case-by-case basis.
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We investigated whether caffeine ingestion before submaximal exercise bouts would affect supramaximal oxygen demand and maximal accumulated oxygen deficit (MAOD), and if caffeine-induced improvement on the anaerobic capacity (AC) could be detected by different methods. Nine men took part in several submaximal and supramaximal exercise bouts one hour after ingesting caffeine (5 mgkg⁻¹) or placebo. The AC was estimated by MAOD, alternative MAOD, critical power, and gross efficiency methods. Caffeine had no effect on exercise endurance during the supramaximal bout (caffeine: 131.3 ± 21.9 and placebo: 130.8 ± 20.8 s, P = 0.80). Caffeine ingestion before submaximal trials did not affect supramaximal oxygen demand and MAOD compared to placebo (7.88 ± 1.56 L and 65.80 ± 16.06 kJ vs. 7.89 ± 1.30 L and 62.85 ± 13.67 kJ, P = 0.99). Additionally, MAOD was similar between caffeine and placebo when supramaximal oxygen demand was estimated without caffeine effects during submaximal bouts (67.02 ± 16.36 and 62.85 ± 13.67 kJ, P = 0.41) or when estimated by alternative MAOD (56.61 ± 8.49 and 56.87 ± 9.76 kJ, P = 0.91). The AC estimated by gross efficiency was also similar between caffeine and placebo (21.80 ± 3.09 and 20.94 ± 2.67 kJ, P = 0.15), but was lower in caffeine when estimated by critical power method (16.2 ± 2.6 vs. 19.3 ± 3.5 kJ, P = 0.03). In conclusion, caffeine ingestion before submaximal bouts did not affect supramaximal oxygen demand and consequently MAOD. Otherwise, caffeine seems to have no clear positive effect on AC. © 2017 Arcoverde et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Although the use of nutritional supplements by adult athletes has been extensively studied, information on supplements consumption by adolescent athletes is still limited. The present study reports on the use of nutritional supplements contaminated with banned doping substances among 170 recreational adolescent athletes from eleven, randomly selected, gym centres, in Athens, Greece. Nutritional supplements consumption was reported by almost 60% of the study population, with proteins/amino acids and vitamins being the most popular. Nine per cent of the users were found to consume nutritional supplements contaminated with anabolic steroids, prohormones, selective androgen receptor modulators (SARMs) and aromatase inhibitors, all pharmacological substances with endocrine modulating properties not stated on the label. None of these individuals had previously consulted a physician or a nutritionist. A representative sample (ca 15%) of the protein/aminoacids and creatine preparations used by the study population were also tested and found free from doping substances. The majority (63%) of adolescents purchased products from the internet. In conclusion, exercising adolescents can have easy access to contaminated nutritional supplements and "black market" products, which could constitute a risk for public health. Low level of awareness and low involvement of medical care professionals among recreational adolescent athletes is also observed.
Context: With the increasing use of unregulated dietary supplements, athletes are at continued risk from adverse medical events and inadvertent doping. Evidence acquisition: A review of Clinical Key, MEDLINE, and PubMed databases from 2012 to 2017 was performed using search terms, including dietary supplement, contamination, doping in athletes, inadvertent doping, and prohibited substances. The references of pertinent articles were reviewed for other relevant sources. Study design: Clinical review. Level of evidence: Level 3. Results: Poor manufacturing processes and intentional contamination with many banned substances continue to occur in dietary supplements sold in the United States. Certain sectors, such as weight loss and muscle-building supplements, pose a greater threat because they are more likely to be contaminated. Conclusion: Athletes will continue to be at risk for adverse events and failed doping tests due to contaminated dietary supplements until legislation changes how they are regulated. In the interim, there are several steps that can be taken to mitigate this risk, including improved education of medical staff and athletes and use of third party-certified products.