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High Prevalence of Cannabidiol Use Within Male Professional Rugby Union and League Players: A Quest for Pain Relief and Enhanced Recovery


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Rugby is characterized by frequent high-intensity collisions, resulting in muscle soreness. Players consequently seek strategies to reduce soreness and accelerate recovery, with an emerging method being cannabidiol (CBD), despite anti-doping risks. The prevalence and rationale for CBD use in rugby has not been explored; therefore, we recruited professional male players to complete a survey on CBD. Goodness of fit chi-square (χ ² ) was used to assess CBD use between codes and player position. Effects of age on use were determined using χ ² tests of independence. Twenty-five teams provided 517 player responses. While the majority of players had never used CBD ( p < .001, V = 0.24), 26% had either used it (18%) or were still using it (8%). Significantly more CBD use was observed in rugby union compared with rugby league ( p = .004, V = 0.13), but player position was not a factor ( p = .760, V = 0.013). CBD use increased with players’ age ( p < .001, V = 0.28), with mean use reaching 41% in the players aged 28 years and older category ( p < .0001). The players using CBD primarily used the Internet (73%) or another teammate (61%) to obtain information, with only 16% consulting a nutritionist. The main reasons for CBD use were improving recovery/pain (80%) and sleep (78%), with 68% of players reporting a perceived benefit. These data highlight the need for immediate education on the risks of CBD, as well as the need to explore the claims regarding pain and sleep.
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High Prevalence of Cannabidiol Use Within Male Professional
Rugby Union and League Players: A Quest for Pain Relief
and Enhanced Recovery
Andreas M. Kasper
Liverpool John Moores University
S. Andy Sparks
Edge Hill University
Matthew Hooks, Matthew Skeer, Benjamin Webb, Houman Nia,
James P. Morton, and Graeme L. Close
Liverpool John Moores University
Rugby is characterized by frequent high-intensity collisions, resulting in muscle soreness. Players consequently seek strategies
to reduce soreness and accelerate recovery, with an emerging method being cannabidiol (CBD), despite anti-doping risks.
The prevalence and rationale for CBD use in rugby has not been explored; therefore, we recruited professional male players to
complete a survey on CBD. Goodness of t chi-square (χ
) was used to assess CBD use between codes and player position.
Effects of age on use were determined using χ
tests of independence. Twenty-ve teams provided 517 player responses. While
the majority of players had never used CBD (p<.001, V= 0.24), 26% had either used it (18%) or were still using it (8%).
Signicantly more CBD use was observed in rugby union compared with rugby league (p= .004, V= 0.13), but player position
was not a factor (p= .760, V= 0.013). CBD use increased with playersage (p<.001, V= 0.28), with mean use reaching 41% in
the players aged 28 years and older category (p<.0001). The players using CBD primarily used the Internet (73%) or another
teammate (61%) to obtain information, with only 16% consulting a nutritionist. The main reasons for CBD use were improving
recovery/pain (80%) and sleep (78%), with 68% of players reporting a perceived benet. These data highlight the need for
immediate education on the risks of CBD, as well as the need to explore the claims regarding pain and sleep.
Keywords:CBD, cannabis, DOMS, supplement
Rugby is a high-intensity collision sport that involves low-
intensity aerobic activities (e.g., standing, walking, and jogging)
combined with frequent periods of intermittent, intensive anaerobic
activities (e.g., sprinting, side stepping, passing, and collisions;
Austin & Kelly, 2013;Twist et al., 2014). In 1895, the game of
rugby was split into two variations—“leagueand union”—and,
despite differences in laws, the two games share many common
modalities with both based around frequent high-speed collisions.
As a consequence of these repeated collisions, players from both
codes of rugby experience increased markers of inammation
(Cunniffe et al., 2011) and muscle soreness (Twist et al., 2012).
The muscle soreness in rugby is particularly pronounced, given it is
a combination of both exercise- and impact-induced muscle dam-
age (Naughton et al., 2017). This pain is often debilitating, affect-
ing everyday function, and can last several days postgame and
remain throughout the entire season (Fletcher et al., 2016). Players
and support staff, therefore, constantly strive to improve recovery
strategies and reduce pain with an emerging method being the use
of cannabidiol (CBD).
It is important to appreciate the fundamental difference
between cannabis and CBD. The cannabis plant contains over
100 cannabinoids, with the two most well-known being CBD and
tetrahydrocannabinol (THC). Although the exact nomenclature
has been argued (Piomelli & Russo, 2016), broadly speaking, the
cannabis plant has two major strainsCannabis indica and
Cannabis sativa.TheCannabis sativa L-strain, more commonly
referred to as hemp, must contain less than 0.20.3% dry weight
THC, whereas other strains can contain up to 30% dry weight
THC and are often referred to as marijuana. Many European
countries have recognized the commercial value of hemp, and
a legal limit of 0.20.3% Δ
-THC is usually applied (Pellati et al.,
2018). This difference in THC concentration is crucial, given that
THC is the major psychotropic substance in cannabis, and it is
often the primary reason why marijuana is grown, whereas hemp
is grown for a variety of reasons, including clothing, shoes, rope,
insulation, biofuel, protein supplementation, and to produce CBD
as a nutritional supplement and/or medicine. While there are
country to country variations in the legality of CBD, in the United
Kingdom, CBD can be legally sold, providing that it does not
contain more than 1 mg of the controlled drug (or 1 μg, in the case
Kasper, Hooks, Skeer, Webb, Nia, Morton, and Close are with the Research Institute
for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool,
United Kingdom. Sparks is with the Sport Nutrition and Performance Research
Group, Department of Sport and Physical Activity, Edge Hill University, Ormskirk,
United Kingdom. Close ( is corresponding author.
International Journal of Sport Nutrition and Exercise Metabolism, 2020, 30, 315-322
© 2020 Human Kinetics, Inc. ORIGINAL RESEARCH
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of lysergide or any other N-alkyl derivative of lysergamide) in the
nal container,that is, in the bottle or packet that it is sold in
(United Kingdom Government Home Ofce, 2020). Almost all
other cannabinoids, except CBD, remain subject to the Misuse of
Drugs Act 1971. There are a variety of forms of CBD that are
commercially available for sale, including oils, capsules, sprays,
tinctures, and gummies. From an athletic perspective, numerous
claims have been made to suggest the possible benets for athletic
It has been reported that CBD possesses anxiolytic, anti-
inammatory, anti-oxidative, and analgesic properties(Bergamaschi
et al., 2011;Mechoulam & Hanus, 2002), as well as suggested that it
improves sleep quality (Russo et al., 2007). Importantly, it has also
been suggested that CBD has a relative safe adverse effects prole
(Bergamaschi et al., 2011), with side effects including tiredness and
changes in appetite and weight (Ifand & Grotenhermen, 2017). The
majority ofresearch into CBD and inammation has been performed
in rodent models (Xiong et al., 2012), and therefore the evidence
supporting its practical application with athletes, at present, remains
weak (Close et al., 2019). Moreover, CBD research is usually
performed in combination with other cannabinoids, commonly THC
(van de Donk et al., 2019), in something referred to as the entourage
effect (Russo, 2019), raising doubts over the efcacy of pure CBD
supplementation for athletes.
Although it is possible to produce synthetic CBD, in Europe,
CBD must come from an industrial hemp strain than is European
Union approved or come from outside the European Union. Given
that CBD must come from the hemp plant, it is of no surprise that
traces of THC are usually found in CBD products. While, legally,
theremustbelessthan1mgofTHCinthenal container, recent
reports have suggested that this is not always the case, with
studies suggesting that some commercially available products
contain signicantly higher amounts of THC than stated on the
label, even, in some cases, greater than the legal threshold (Gurley
et al., 2020), along with other illegal cannabinoids (Poklis et al.,
2019). From an athletic perspective, this is worrying not only
from a legal perspective but also in terms of an anti-doping viola-
tion, given that all cannabinoids, except CBD, are currently pro-
hibited substances by the world Anti-Doping Agency (WADA).
Despite CBD being removed from the WADA prohibited list in
2018 (both in and out of competition), its use in professional sport
remains highly contentious and poses a signicant risk to athletes.
This is not only due to the possibility of THC being present in
excess of the legal threshold, but also, to date, there has been no
research to suggest what effects taking varying amounts of legal
CBD has on urine THC concentrations. It is for these reasons
that many sporting bodies currently advise against CBD use;
however, media reports would suggest that athletes are ignoring
this advice and using it to enhance recovery. It is, therefore,
essential that the prevalence and rationale for CBD use is studied
to guide immediate education strategies and highlight areas for
future research.
To this end, the aim of the present study was to establish the
prevalence of CBD use in a large sample (>500) of professional
rugby league and union players. Rugby was chosen as the sport to
study given that media reports have suggested that there are many
players using CBD and because the nature of the sport is one
whereby remedies to alleviate muscle soreness are frequently used.
We hypothesized that CBD use (past and present) would be high
(>20%) in professional players, with an increasing prevalence in
the older players and those players who play in the forward
Overall Study Design
Professional male players from 30 rugby teams competing within
the English Premiership, U.K.-based Pro 14 (Rugby Union) and
Super League (Rugby League) competitions were invited to par-
ticipate in this observational study. Data were collected during the
20192020 season from 25 clubs (from the 30 invited), totaling 517
responses. At the time of data collection, all players were part of the
senior squad and aged 18 years and older. All English Premiership
teams and Scottish Pro 14 teams, 25% of Welsh Pro 14 teams, and
83% of Super League teams participated (Figure 1). Players were
given a short anonymous online multiple-choice survey consisting
of 15 questions surrounding CBD use products, with assumed
consent provided via a consent statement and submission of the
survey. Each team was provided a code, only known by the lead
researcher, to identify teams for relevant feedback where requested
by organizations. Survey responses were coded and entered into
Microsoft Excel prior to analysis. The study was approved by
Liverpool John Moores University Ethics Committee (M20_SPS_
966, 21/02/20).
Survey Design
The survey was designed by the research team, with extensive
experience within the elite rugby environment, to identify the
current use of CBD within elite rugby and to assess athlete under-
standing and knowledge of key areas. A copy of the survey can be
seen within Appendix. In brief, the survey was split into eight
sections: (a) demographics (age, code of rugby, and positional
group), (b) awareness of CBD, (c) use of CBD, (d) rationale for use,
(e) experience of use, (f) efcacy of use, (g) understanding of anti-
doping, and (h) further comments.
Data Analysis
Data were organized based on demographic information for age
group (1823, 2328, and >28 years), rugby code (league and
union), player position (forwards and backs), and team. Data are
presented as percentage of responses, but analysis was conducted
on the frequency data. Goodness of t chi-square (χ
) was used to
assess CBD use in the sample population, between codes and
player position. Effect sizes were calculated using CramersV,
which was interpreted as small (0.10.3), medium (0.30.5), and
large (>0.5). Chi-square tests of independence were used to deter-
mine differences between age groups. Post hoc analysis was
conducted by calculating Bonferroni adjusted pvalues from ad-
justed standardized residuals. A KruskalWallis one-way analysis
of variance was used to assess differences between teams. Effect
sizes were calculated using epsilon square (ε
) and were interpreted
as weak (<0.04), moderate (0.040.16), and strong (0.641.0),
respectively. Statistical signicance was set at p<.05, apart from
Bonferroni adjusted pvalues, which were calculated as the pvalue
from the adjusted standardized residuals divided by the degrees of
freedom. All data were analyzed using SPSS for Windows (version
25; IBM, Armonk, NY).
There were a total of 18 U.K.-based teams that competed within the
English Premiership and Pro 14 rugby union competitions, along
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316 Kasper et al.
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with 12 teams that competed within the Super League rugby league
competition. Out of these, 517 players from 25 teams responded to
the survey (Figure 1).
The mean age of players who responded was 25 (SD = 5, range
1833) years. Sixty-seven percent (of the 517 respondents) came
from rugby union, with the remaining 33% from rugby league.
Of those who responded, 40% identied themselves as backs and
60% as forwards (Figure 1).
Awareness and Use of CBD
Of those responders to the survey, 91% (n= 472) indicated that
they had an awareness of CBD. Awareness came from a variety of
sources: Internet (73%), another teammate (61%), another player/
club (41%), nutritionist (16%), other staff members (4%), family/
friends (2%), the media (1%), and research (<1%; Figure 2a). Of
the 472 players that were aware of CBD (Figure 3a), signicantly
more players had never used it (χ
= 121.9, p<.001, V= 0.24);
however a considerable proportion (26%) were either currently
(8%) or had previously (18%) used CBD. The proportion of
players either using or who had used CBD (Figure 4) varied signi-
cantly across the teams sampled (H= 278.0, p<.001, ε
= 0.59).
A signicantly higher number of players from rugby union
had either used or were using CBD (χ
= 8.29, p= .004, V=
0.13), but there were no observed differences between backs and
forwards (χ
= 0.09, p= .760, V= 0.013). Interestingly, CBD use
was signicantly different across the age groups (χ
= 40.60,
p<.001, V= 0.28), with a lower number of players in the 18
23 years age group (p<.0001) and more than expected players
using CBD in the 28 years and older age group (p<.0001). This
contrasted with the 2328 years age group, which was not
observed to be signicantly different from the expected number
of users (p= .053).
Rationale for Use
Of the 472 players aware of CBD, 339 had never used CBD. The
reasons surrounding this included being concerned about anti-doping
rule violations (ADRV; 64%), not aware of any benet(37%),not
perceiving a need (29%), club advised against taking (23%), too
costly (2%), have not had the chance (1%), concerned about possible
side effects (1%), and lack of scienticevidence(<1%) (Figure 2b).
For the remaining 133 players who previously/currently used
CBD, the reasons were equally varied, including improving recov-
ery/pain (80%), sleep (78%), anxiety (32%), and for other medical
purposes (14%: help with concussion, long-term injury, and che-
motherapy; Figure 2c).
Figure 1 Overview of recruitment for survey. CBD = cannabidiol.
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CBD Use in Professional Rugby 317
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Experience and Efcacy of CBD Use
Thirteen different CBD brands were being used by athletes, all
of which were oils or capsules. There was a disparity in reported
dose with athletes quoting percentages, drops, mgs, sprays, and
rice-sizedquantities. Indeed, there was also diversity in the con-
centrations of CBD reportedly taken, ranging from 400 to 3,000 mg/
510% solutions in forms of drops (310 drops), tablets (10 mg), and
rice-sizedquantities (one grain). A number of players (6%) were
either unsure of the brand they were using or mixing multiple brands,
with a further 39% unsure of the dose they were taking.
Despite the disparity in dose taken, many of the players
currently or previously taking CBD (n= 133) anecdotally perceived
abenet (67%), including improved sleep (41%), recovery/pain
(14%), mood (6%), anxiety (3%), and other various medical pur-
poses (8%: concussion, chemotherapy, and long-term injury). No
player reported any perceived adverse effects (Figure 2d).
Understanding of Anti-Doping and Further
Of the players (n= 133) who had taken or were currently taking CBD,
52% were not concerned of committing an ADRV, with a further
79% believing the product they use to be batch tested for banned
substances and 21% unsure or aware that the product is not tested.
Of the 107 players that included additional commentary, 14%
used this space to indicate that they would try CBD in the future,
with 13% still unsure of the legality in and out of sport.
The aim of the present study was to establish the prevalence
and reasons for CBD use in an extensive sample of elite rugby
players. To this end, we recruited 517 professional rugby players to
Figure 2 Sources of information (a), reasons against (b), reasons for (c), and perceived benets (d) of taking cannabidiol oil. ADRV = anti-doping
rule violations.
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complete an online survey. We report, for the rst time in elite
rugby players, that despite warnings from clubs and national
governing bodies against CBD use, >25% of all athletes surveyed
have either used or continue to use CBD. Moreover, in the older
players (>28 years old), almost 40% have or continue to use CBD,
with the major reasons cited including pain relief/recovery and to
improve sleep quality. These data suggest that many rugby players
are willing to accept the risks associated with CBD use in an
attempt to accelerate recovery and/or improve sleep. In addition
to the denitive requirement for immediate player education with
regard to the safety and risks of CBD supplementation, future
research should now also assess the efcacy of CBD supplements
on factors inuencing recovery (e.g., pain, soreness, inamma-
tion, sleep).
Rugby match play has been shown to result in both exercise-
and impact-induced muscle damage (Twist et al., 2012) that lasts
for several days postgame and persists throughout the entire
playing season (Fletcher et al., 2016). Daily muscle pain, especially
nerve pain, has been shown to have both physical (Cheung et al.,
2003) and psychological consequences that negatively affect daily
quality of life and even family life (Duenas et al., 2016). It is,
therefore, of little surprise that athletes have been shown to have
four times the use of painkillers compared with the general public
(Alaranta et al., 2006). Although research from other sports has
documented a high prevalence of painkiller use (Taioli, 2007;
Tsitsimpikou et al., 2009), data on rugby players are lacking. This
is despite the suggestion, both in academic literature (Gibbison
et al., 2014) and multiple reports in the mainstream media, that
rugby players are particularly reliant on the use of painkillers, such
as non-steroidal anti-inammatory drugs, and opiates such as
Tramadol. The side effects associated with the chronic use of non-
steroidal anti-inammatory drugs include gastric injury, gastric
ulceration, and kidney damage (Bertolini et al., 2001). Importantly
for rugby, increased risks also include bleeding and/or intracranial
hemorrhage post minor head injury (Sakr & Wilson, 2005).
Tramadol, which has been suggested to be widely used in rugby
players in the media, is effective in treating neuropathic pain
(Bravo et al., 2017); however, it is also not without serious side
effects, including nausea, headaches constipation, sleep distur-
bances (Walder et al., 2001), and withdrawal effects, as well as
drowsiness, which can signicantly impair training and perfor-
mance. Given the muscle damage induced by rugby match play and
training (Hudson et al., 2019), combined with the side effects of
traditional pain medication, rugby players are now seeking alter-
nate pain relief strategies and ways to improve sleep.
We report that 78% and 80% of players used CBD to improve
sleep and pain/recovery, respectively. Interestingly, in the present
study, although the mean use of CBD was 26%, there was
increasing prevalence of use with increasing age, with the mean
usage reaching 39% in the players aged 28 years and older
category. Although it was not possible to assess the reason for
this, one could speculate that it is the older players who have
residual pain through a longer playing history, and that they are
more likely to be seeking pain relief medication. Of all the players
who have used CBD, 67% reported a perceived benet of use, with
41% reporting improved sleep and 14% improved pain/recovery.
Interestingly, no athletes reported any adverse side effects,
although it must be considered that players may have taken a
negligible dose of CBD and/or taken a product with far less CBD
than stated on the label (Gurley et al., 2020), and therefore this
study should not be used as evidence that CBD does not cause side
effects. Future research should now be performed to explore the
veracity of such claims, which could have important consequences
for future advice and guidance offered to players.
Although the mean current/previous use of CBD was 26%, it
was interesting to observe that there was a signicant difference
between teams with current/previous use ranging, from 5% to 70%.
Figure 3 Varying usage (%) of CBD oil across (a) all surveyed
players, (b) different ages, (c) different codes, and (d) different playing
position. Bars represent data from those who currently (black), previously
(gray), or have never (white) taken CBD oil. CBD = cannabidiol.
Figure 4 Individual team usage of CBD oil ranked lowest to highest
for previous/current use of CBD. Bars represent data from those who
currently (black), previously (gray), or have never (white) taken CBD oil.
CBD = cannabidiol.
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Alarmingly, the players reported that the major source of CBD
information was either the Internet (73%) or a teammate (61%). It
is, therefore, possible that the interteam range could be related to
some players within a club having a major inuence, although this
suggestion could not be fully explored in the present study and
should now be investigated further. This suggestion is, however,
further supported by the fact that only 16% and 4% sourced their
information from the team nutritionist or other staff member,
respectively. This low reliance on the team nutritionist could be
due to most clubs and governing bodies advising against CBD use
and, as a consequence, players not feeling comfortable to discuss
the potential use of CBD with internal staff members. Indeed, 23%
of players who did not use CBD cited their main reason not to use
was that the club had advised against it. In the free comments
section of the survey, 14% of players stated that they would like to
try CBD in the future. It is, therefore, crucial that players feel
comfortable discussing CBD with qualied staff rather than relying
on the Internet and/or other team members for their information
(Maughan et al., 2018).
Despite CBD being removed from the WADA prohibited list
in 2018, CBD use still poses a signicant risk to athletes due to the
possibility of THC and other prohibited cannabinoids being present
in quantities sufcient to produce a urine sample greater than the
current threshold. Although 64% of players did not use CBD due
to fears of an ADRV, only 48% of current/previous users were
concerned about such a violation. In the free comments section,
13% of players stated that they were unsure of the legality of CBD
in rugby. The survey also asked athletes if they were aware if their
supplement was batch tested for other contaminants. Alarmingly,
21% of users did not know if their CBD supplement was batch
tested, whereas 79% claimed that the CBD product they were
consuming was tested. This belief that the product was tested was
of particular concern given that of all the CBD products listed, only
one appeared to be tested (tested by BSCG), yet just 39% of the
players reported to be using this specic product. It is, therefore,
likely that some players wrongly assumed that the CBD product
they were taking was batch tested, which could be related to the
lack of qualied advice they had received. Given that rates of
supplement contamination, which could result in an ADRV, have
been reported as high as 1258% (Martínez-Sanz et al., 2017),
combined with the risks associated with CBD, it appears that many
rugby players are prepared to risk an ADRV and subsequent sanctions
in a quest to attenuate their pain and enhance recovery (including
promotion of sleep). This conrms the need for appropriate education
as well as greater efforts to provide appropriate pain relief for players.
The present study is not without its limitations, most of which
are a consequence of collecting data in professional athletes along-
side the collection of data that occurred during the COVID-19 crisis.
Although we managed to recruit more than 500 players, some teams
declined to participate in the research, with reasons cited including
the furlough of players and the potential for confusion, given they
had advised their players against using CBD. It is feasible that
players who had been advised not to use CBD did not take part in the
study, and, likewise, the players who did agree to participate may
have had more of an interest in CBD than those who declined. This
potential for systemic bias could have either overestimated or
underestimated the reported prevalence, which is a common prob-
lem in survey data when the entire population is not recruited.
Nonetheless, we are condent that with 25 teams and a mean of
21 players per team, these data do reect the genuine usage within
elite professional rugby. Moreover, due to the anonymous nature of
the data collection, it was not possible to explore in depth the
rationale for usage and the perceived benets. It was felt that the
anonymous nature was essential, given that the advice from the
clubs was not to use CBD, and, by keeping it anonymous, it would
allow us to collect more robust data. Future research should now
consider a more qualitative approach to fully understand the deci-
sions made by rugby players when it comes to CBD use. Finally,
while players did report benets of CBD use, this could certainly be
a placebo effect, given that, to date, there are no randomized
placebo-controlled trials on the effects of CBD on recovery and
sleep in athletes. Future research must now address this gap in the
literature as well as assess the potential for CBD use to raise THC
concentrations above the current WADA thresholds.
In conclusion, we report, for the rst time, a high prevalence of
CBD use, along with the rationale for its use in elite rugby players.
The data suggest that despite the majority of clubs advising against
CBD use, many players are ignoring this advice in an attempt to
improve sleep and pain management. These data highlight the need
for immediate education for rugby players on the potential con-
sequences of CBD use, as well as highlighting the need for future
research into the efcacy of CBD and the veracity of the anecdotal
claims from the players that it does help alleviate pain, enhance
recovery, and promote sleep.
The study was designed by A.M. Kasper, M. Hooks, M. Skeer, B. Webb,
H. Nia, J.P. Morton, and G.L. Close; data were collected and analyzed by
A.M. Kasper, M. Hooks, S.A. Sparks, and G.L. Close; and data interpre-
tation and manuscript preparation were undertaken by A.M. Kasper, J.P.
Morton, S.A. Sparks, and G.L. Close. All authors approved the nal
version of the article.
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... Participants were recruited from numerous sports, including Australian football (n = 3) [37,54,59], basketball (n = 2) [40,69], cycling (n = 4) [43,56,60,63], multiple individual and team sports (n = 9) [61,68,71,78,[80][81][82][83][84], Paralympic sports (n = 1) [79], rhythmic gymnastics (n = 1) [62], rugby (n = 6), running (n = 2) [65,76], soccer (n = 1) [73], swimming (n = 1) [67], and triathlon (n = 3) [55,63,76], with four studies not specifying their participants involvement in sports [57,58,74,85]. Studies were mostly conducted in Australia (n = 9) [37,54,59,61,63,64,66,71,72], followed by Japan (n = 5) [78,79,[81][82][83], Spain (n = 3) [65,69,73], United Kingdom (n = 3) [56,70,77], and New Zealand (n = 3) [67,68,75]. ...
... These studies were categorized into main themes based on the dietary factor(s) examined; macronutrients, micronutrients and energy, dietary supplements, and dietary patterns. All studies were published between 2010 and 2022, with 83% (n = 29) published between 2018 and 2022 [37,40,43,54,[57][58][59][60][61][62][64][65][66][69][70][71][72][73][74][75][77][78][79][80][81][82][83][84][85]. Females were recruited in 18 studies (51%) [43,54,58,[60][61][62]67,68,71,76,[78][79][80][81][82][83][84][85], with only 23% of studies (n = 8) recruiting females exclusively [54,58,61,62,68,76,82,85], compared to 49% for males [37,40,[55][56][57]59,[63][64][65][66]69,70,[72][73][74][75]77]. ...
... All studies were published between 2010 and 2022, with 83% (n = 29) published between 2018 and 2022 [37,40,43,54,[57][58][59][60][61][62][64][65][66][69][70][71][72][73][74][75][77][78][79][80][81][82][83][84][85]. Females were recruited in 18 studies (51%) [43,54,58,[60][61][62]67,68,71,76,[78][79][80][81][82][83][84][85], with only 23% of studies (n = 8) recruiting females exclusively [54,58,61,62,68,76,82,85], compared to 49% for males [37,40,[55][56][57]59,[63][64][65][66]69,70,[72][73][74][75]77]. Of the 35 studies, 21 were randomized control trials [40,43,[55][56][57][58][59][60][61]63,65,[67][68][69][70][72][73][74][75][76]85], four were prospective cohort studies [37,54,64,66], and ten were cross-sectional survey designs [62,71,[77][78][79][80][81][82][83][84]. ...
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Many athletic populations report poor sleep, especially during intensive training and competition periods. Recently, diet has been shown to significantly affect sleep in general populations; however, little is known about the effect diet has on the sleep of athletically trained populations. With sleep critical for optimal recovery and sports performance, this systematic review aimed to evaluate the evidence demonstrating that dietary factors influence the sleep of athletically trained populations. Four electronic databases were searched from inception to May 2022, with primary research articles included if they contained a dietary factor(s), an outcome measure of sleep or sleepiness, and participants could be identified as ‘athletically trained’. Thirty-five studies were included, with 21 studies assessed as positive quality, 13 as neutral, and one as negative. Sleep or sleepiness was measured objectively in 46% of studies (n = 16). The review showed that evening (≥5 p.m.) caffeine intakes >2 mg·kg−1 body mass decreased sleep duration and sleep efficiency, and increased sleep latency and wake after sleep onset. Evening consumption of high glycaemic index carbohydrates and protein high in tryptophan may reduce sleep latency. Although promising, more research is required before the impact of probiotics, cherry juice, and beetroot juice on the sleep of athletes can be resolved. Athletic populations experiencing sleep difficulties should be screened for caffeine use and trial dietary strategies (e.g., evening consumption of high GI carbohydrates) to improve sleep.
... In fact, since the World Anti-Doping Agency (WADA) no longer considers CBD as a prohibited substance, 15 CBD use among athletes is emerging. A study in elite rugby players showed a prevalence of 26%, 16 which is a high number driven by a perceived improvement in recovery and a reduction in pain. 16 As athletes are often subjected to strenuous exercise sessions that induce microstructural damage to the skeletal muscle, that is, exercise-induced muscle damage (EIMD), 17,18 they are continuously searching for ergogenic aids to improve their recovery process. ...
... A study in elite rugby players showed a prevalence of 26%, 16 which is a high number driven by a perceived improvement in recovery and a reduction in pain. 16 As athletes are often subjected to strenuous exercise sessions that induce microstructural damage to the skeletal muscle, that is, exercise-induced muscle damage (EIMD), 17,18 they are continuously searching for ergogenic aids to improve their recovery process. EIMD goes along with inflammatory responses and a sensation of delayed onset of muscle soreness (DOMS), and eventually leads to decreased muscle performance. ...
Background: Cannabidiol (CBD), a nonintoxicating constituent of the cannabis plant, recently gained a lot of interest among athletes, since it is no longer considered as a prohibited substance by the World Anti-Doping Agency. The increasing prevalence of CBD use among athletes is driven by a perceived improvement in muscle recovery and a reduction in pain. However, compelling evidence from intervention studies is lacking and the precise mechanisms through which CBD may improve muscle recovery remain unknown. This highlights the need for more scientific studies and an evidence-based background. In the current review, the state-of-the-art knowledge on the effects of CBD on skeletal muscle tissue is summarized with special emphasis on the underlying mechanisms and molecular targets. More specifically, the large variety of receptor families that are believed to be involved in CBD's physiological effects are discussed. Furthermore, in vivo and in vitro studies that investigated the actual effects of CBD on skeletal muscle metabolism, inflammation, tissue regeneration, and anabolism are summarized, together with the functional effects of CBD supplementation on muscle recovery in human intervention trials. Overall, CBD was effective to increase the expression of metabolic regulators in muscle of obese mice (e.g., Akt, glycogen synthase kinase-3). CBD treatment in rodents reduced muscle inflammation following eccentric exercise (i.e., nuclear factor kappa B [NF-κB]), in a model of muscle dystrophy (e.g., interleukin-6, tumor necrosis factor alpha) and of obesity (e.g., COX-2, NF-κB). In addition, CBD did not affect in vitro or in vivo muscle anabolism, but improved satellite cell differentiation in dystrophic muscle. In humans, there are some indications that CBD supplementation improved muscle recovery (e.g., creatine kinase) and performance (e.g., squat performance). However, CBD doses were highly variable (between 16.7 and 150 mg) and there are some methodological concerns that should be considered. Conclusion: CBD has the prospective to become an adequate supplement that may improve muscle recovery. However, this research domain is still in its infancy and future studies addressing the molecular and functional effects of CBD in response to exercise are required to further elucidate the ergogenic potential of CBD.
... Introduction sleep (78%), reduce anxiety (32%), and for "other" medical purposes (14%; e.g. concussion) [16]. ...
... Despite its growing popularity [16], only two interventional studies, both randomised, double-blind, placebocontrolled crossover trials, have so far investigated the effects of CBD on outcomes relevant to athletic performance. The first found no effect of CBD (150 mg·d −1 for 3 days) on non-invasive measures of muscle damage following eccentric exercise [19]. ...
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Background Cannabidiol (CBD) has demonstrated anti-inflammatory, analgesic, anxiolytic and neuroprotective effects that have the potential to benefit athletes. This pilot study investigated the effects of acute, oral CBD treatment on physiological and psychological responses to aerobic exercise to determine its practical utility within the sporting context. Methods On two occasions, nine endurance-trained males (mean ± SD V̇O 2max : 57.4 ± 4.0 mL·min ⁻¹ ·kg ⁻¹ ) ran for 60 min at a fixed intensity (70% V̇O 2max ) (RUN 1) before completing an incremental run to exhaustion (RUN 2). Participants received CBD (300 mg; oral) or placebo 1.5 h before exercise in a randomised, double-blind design. Respiratory gases (V̇O 2 ), respiratory exchange ratio (RER), heart rate (HR), blood glucose (BG) and lactate (BL) concentrations, and ratings of perceived exertion (RPE) and pleasure–displeasure were measured at three timepoints (T1–3) during RUN 1. V̇O 2max , RER max , HR max and time to exhaustion (TTE) were recorded during RUN 2. Venous blood was drawn at Baseline, Pre- and Post-RUN 1, Post-RUN 2 and 1 h Post-RUN 2. Data were synthesised using Cohen’s d z effect sizes and 85% confidence intervals (CIs). Effects were considered worthy of further investigation if the 85% CI included ± 0.5 but not zero. Results CBD appeared to increase V̇O 2 (T2: + 38 ± 48 mL·min ⁻¹ , d z : 0.25–1.35), ratings of pleasure (T1: + 0.7 ± 0.9, d z : 0.22–1.32; T2: + 0.8 ± 1.1, d z : 0.17–1.25) and BL (T2: + 3.3 ± 6.4 mmol·L ⁻¹ , d z : > 0.00–1.03) during RUN 1 compared to placebo. No differences in HR, RPE, BG or RER were observed between treatments. CBD appeared to increase V̇O 2max (+ 119 ± 206 mL·min ⁻¹ , d z : 0.06–1.10) and RER max (+ 0.04 ± 0.05 d z : 0.24–1.34) during RUN 2 compared to placebo. No differences in TTE or HR max were observed between treatments. Exercise increased serum interleukin (IL)-6, IL-1β, tumour necrosis factor-α, lipopolysaccharide and myoglobin concentrations (i.e. Baseline vs. Post-RUN 1, Post-RUN 2 and/or 1-h Post-RUN 2, p ’s < 0.05). However, the changes were small, making it difficult to reliably evaluate the effect of CBD, where an effect appeared to be present. Plasma concentrations of the endogenous cannabinoid, anandamide (AEA), increased Post-RUN 1 and Post-RUN 2, relative to Baseline and Pre-RUN 1 ( p ’s < 0.05). CBD appeared to reduce AEA concentrations Post-RUN 2, compared to placebo (− 0.95 ± 0.64 pmol·mL ⁻¹ , d z : − 2.19, − 0.79). Conclusion CBD appears to alter some key physiological and psychological responses to aerobic exercise without impairing performance. Larger studies are required to confirm and better understand these preliminary findings. Trial Registration This investigation was approved by the Sydney Local Health District’s Human Research Ethics Committee (2020/ETH00226) and registered with the Australia and New Zealand Clinical Trials Registry (ACTRN12620000941965).
... 3 The present use of cannabis in sport is largely determined by peer contact, information on the Internet and other promotional activity. 4,5 Numerous high-profile sporting identities in the United States promote cannabis as an adjunct to training, to improve sleep patterns, prevent neurotrauma or relieve musculoskeletal and other discomforts. These include Ross Rebagliti Olympic snow boarding gold medalist, USA Triathlon partnering with Pure Spectrum CBD and World Surf League appointing cbdMD as official sponsor of the 2019/2020 Jaws Big Wave Championships. ...
... Lesser reasons were anxiety (32%) and a small number of 'medical reasons', which included recovery from concussion. 4 A comprehensive adverse reaction profile for CBD in animals and humans has recently been published. CBD was administered to both children and adults in varying doses of up to 1000 mg per day for different periods of time, including approximately 7 weeks in one study of 88 adult patients with treatment-resistant psychoses. ...
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The World Antidoping Agency now allows cannabidiol (CBD) to be taken in elite sport but has retained all other cannabinoids on its banned list. This, together with liberalisation of cannabis laws have led to an increasing interest in its use in sport. This includes commercial sponsorship of sporting events and highlights the need for accurate information to be readily available to athletes and their advisers. This narrative review confirms that CBD and tetrahydrocannabinol (THC) do not enhance performance. CBD possesses anti‐inflammatory and analgesic properties which have not been adequately evaluated in the area of sport. Some formulations of CBD contain THC or other cannabinoids that may result in a positive drug test. This article is protected by copyright. All rights reserved.
... This particular point may be relevant in the supplements studied because in the case of cannabidiol, research in humans is still needed to establish safe consumption protocols [68]. In a study [69] conducted on rugby players, it was concluded that 25% of them had consumed cannabidiol, 40% to relieve pain or improve sleep. What was relevant was that the athletes turned to internet websites (73%) to find out about the use of the supplement, and only 4% consulted with a professional. ...
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The use of supplements containing herbal active ingredients in sport has increased in recent years. Their consumption is explained by the benefits they may provide and because their natural origin do not involve health complications, from the point of view of the consumers. The aim of this study is to analyze the availability of four supplements (caffeine, turmeric, ginseng, cannabidiol) on the internet and understand the nature of these websites. A descriptive, observational, and cross-sectional study design was used. A detailed search was carried out with specifically developed software. The searches and data evaluation took 10 days. The websites consulted correspond to those that sell supplements, or some sport websites in the case of the Spanish ones, whereas those in English belong to pharmacies, parapharmacies, or herbalists. It is concluded that the websites do not provide adequate information to ensure proper consumption and lack advice on the choices of supplements and their administration guidelines.
... 3 Beyond its clinical application, the increasing national and international legalization of CBD has caused a rise in medicinal use for the treatment of pain, sleeplessness, or as a recovery aid after exercise. 4 Recently, we investigated the effect of acute administration of CBD on molecular signaling in skeletal muscle after eccentric exercise in rats. 5 We found that despite a relatively high dose of intraperitoneal CBD, the overall effect on protein levels in skeletal muscle after exercise was modest. ...
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Background: Cannabidiol (CBD) is becoming increasingly popular for the treatment of clinical conditions including as an aid for muscle recovery. Previous work demonstrated that CBD exhibited mild effects on skeletal muscle, with a tendency to increase anabolic signaling and decrease inflammatory signaling. Methods: To gain mechanistic insight and extend these findings, we conducted a set of experiments using C2C12 myotubes. Results: Increasing the dose of CBD (1-5 μM) provided with insulin-like growth factor 1 (IGF-1) showed no effect on anabolic signaling through mTORC1 (S6K1 [Thr389], p=0.27; rpS6 [Ser240/244], p=0.81; or 4E-BP1 [Thr37/46], p=0.87). Similarly, inflammatory signaling through nuclear factor kappa B (NF-κB) (p105, p=0.88; p50, p=0.93; or phosphorylated p65 [Ser536], p=0.84) in response to tumor necrosis factor α (TNFα) was unaffected by CBD (2.5 μM), whereas dioscin, a natural product that blocks NF-κB signaling, reduced p105 and phosphorylated p65 (Ser536) compared with the TNFα and the TNFα + CBD condition (p<0.01 and p<0.05, respectively). Finally, cannabinoid receptor type 1 (CB1) receptor levels were measured in C2C12 cells, murine skeletal muscle, cortex, and hippocampus. Although CB1 was not detectable in muscle cells or muscle tissue, high levels were observed in brain tissue. Conclusion: In conclusion, CBD does not directly modulate anabolic or inflammatory signaling in myotubes in vitro, which can likely be explained by the lack of functional receptors.
... Also, a quarter of university athletes report using cannabisrelated products (Docter et al., 2020). Especially in contact sports like rugby, the use rate of CBD is 28%, increasing with age, and reporting pain relief and sleep quality improvements as perceived benefits (Kasper et al., 2020). ...
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The use of cannabidiol (CBD) among athletes is becoming extensive and frequent. This could be due to its elimination of CBD from the list of prohibited substances by federations and international institutions of sport. Also, CBD legalization, and production and commercialization allowance could rise it intake. This situation, despite the fact that the use and commercialization of cannabinoids has not ceased, has fueled the race to study their properties, benefits and risks for health and performance in athletes. Although there is evidence that suggests some beneficial properties such as anxiolytics, antidepressants, anti-inflammatory, antioxidants among others, the evidence presented so far is neither clear nor conclusive. In fact, there is a great gap in knowledge regarding the physiological pathways that explain the role of CBD in sports performance. This mini-review aims to expose the evidence suggesting that CBD has the potential to be used as part of strategies to recover from fatigue and muscle damage related to physical and cognitive exertion in sport.
Background: Cannabidiol (CBD), one of the major cannabinoids derived from the cannabis plant, is available over the counter. CBD is often used by patients for the management of insomnia, yet research supporting CBDs effectiveness as a treatment for insomnia is inadequate. Objective: The objective of this review was to critically evaluate the literature regarding the therapeutic benefits of CBD in the management of insomnia. Methods: A comprehensive search of the following databases from inception to December 29, 2021, was conducted: Ovid MEDLINE® and Epub Ahead of Print, In-Process & Other Non-Indexed Citations and Daily, Ovid Embase, Ovid Cochrane Central Register of Controlled Trials, Ovid Cochrane Database of Systematic Reviews, and Scopus. The search included randomized controlled trials, nonrandomized experimental studies, cross-sectional studies, cohort studies, case series, and case reports. Risk of bias was assessed with the Agency for Healthcare Research and Quality design-specific recommended criteria. Results: Thirty-four studies were eligible for inclusion. All studies reported improvement in the insomnia symptoms of at least a portion of their participants. Of the 34 studies, 19 studies used CBD predominant therapy and 21 studies used nearly equal ratios of CBD to Δ9-tetrahydrocannabinol (THC). Of the studies that performed hypothesis testing, 4 of 7 studies with a CBD predominant arm and 12 of 16 studies with a nearly equal ratio of CBD to THC arm reported significant improvement in insomnia outcomes. However, only 2 of the 34 studies focused on patients with insomnia, of which 1 study was a case report. Additionally, several studies used nonvalidated subjective measures, and most studies failed to include objective measures for symptom assessment. Conclusions: The results of our systematic review suggest that CBD alone or with equal quantities of THC may be beneficial in alleviating the symptoms of insomnia. Nevertheless, future research assessing CBDs effectiveness in population of patients specifically with insomnia utilizing validated subjective and objective measures is necessary before definitive inferences can be made.
Background Regulation has not kept pace with the growth of the hemp-derived CBD market. We have evaluated the risk of Δ⁹-tetrahydrocannabinol (Δ⁹-THC) contamination in 80 unregulated products with comparison to a regulated control, Epidiolex®. Methods Local and national brands of hemp-derived oil products were purchased online and from local retailers in central Kentucky (which carry both national and local brands). These were extracted by solvent extraction and quantified by liquid-chromatography tandem mass-spectrometry (LC-MS/MS) using a validated method. Results Of the 80 unregulated products and Epidiolex®, Δ⁹-THC was detected above the limit of quantification (LOQ = 0.005 mg/mL) of the assay in 52 samples, ranging from 0.008 mg/mL to 2.071 mg/mL. Twenty-one of the products tested were labelled as “THC-Free”, and 5 of these products contained detectable levels of Δ⁹-THC ranging from 0.015 mg/mL to 0.656 mg/mL. Conclusions Consumers are taking hemp-derived CBD products without understanding the risks of unintentional consumption of Δ⁹-THC. This accidental use of Δ⁹-THC could have adverse effects on health and safety as well as potential legal consequences (e.g., child custody, impaired driving), as Δ⁹-THC drug test findings could impact employment, military, and sport eligibility status.
Full-text available Sport nutrition is one of the fastest growing and evolving disciplines of sport and exercise science, demonstrated by a 4-fold increase in the number of research papers between 2012 and 2018. Indeed, the scope of contemporary nutrition-related research could range from discovery of novel nutrient-sensitive cell-signalling pathways to the assessment of the effects of sports drinks on exercise performance. For the sport nutrition practitioner, the goal is to translate innovations in research to develop and administer practical interventions that contribute to the delivery of winning performances. Accordingly, step one in the translation of research to practice should always be a well-structured critique of the translational potential of the existing scientific evidence. To this end, we present an operational framework (the “Paper-2-Podium Matrix”) that provides a checklist of criteria for which to prompt the critical evaluation of performance nutrition-related research papers. In considering the (1) research context, (2) participant characteristics, (3) research design, (4) dietary and exercise controls, (5) validity and reliability of exercise performance tests, (6) data analytics, (7) feasibility of application, (8) risk/reward and (9) timing of the intervention, we aimed to provide a time-efficient framework to aid practitioners in their scientific appraisal of research. Ultimately, it is the combination of boldness of reform (i.e. innovations in research) and quality of execution (i.e. ease of administration of practical solutions) that is most likely to deliver the transition from paper to podium.
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The topic of Cannabis curries controversy in every sphere of influence, whether politics, pharmacology, applied therapeutics or even botanical taxonomy. Debate as to the speciation of Cannabis, or a lack thereof, has swirled for more than 250 years. Because all Cannabis types are eminently capable of cross-breeding to produce fertile progeny, it is unlikely that any clear winner will emerge between the “lumpers” vs. “splitters” in this taxonomical debate. This is compounded by the profusion of Cannabis varieties available through the black market and even the developing legal market. While labeled “strains” in common parlance, this term is acceptable with respect to bacteria and viruses, but not among Plantae. Given that such factors as plant height and leaflet width do not distinguish one Cannabis plant from another and similar difficulties in defining terms in Cannabis, the only reasonable solution is to characterize them by their biochemical/pharmacological characteristics. Thus, it is best to refer to Cannabis types as chemical varieties, or “chemovars.” The current wave of excitement in Cannabis commerce has translated into a flurry of research on alternative sources, particularly yeasts, and complex systems for laboratory production have emerged, but these presuppose that single compounds are a desirable goal. Rather, the case for Cannabis synergy via the “entourage effect” is currently sufficiently strong as to suggest that one molecule is unlikely to match the therapeutic and even industrial potential of Cannabis itself as a phytochemical factory. The astounding plasticity of the Cannabis genome additionally obviates the need for genetic modification techniques.
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In this experimental randomized placebo-controlled 4-way crossover trial, we explored the analgesic effects of inhaled pharmaceutical-grade cannabis in 20 chronic pain patients with fibromyalgia. We tested 4 different cannabis varieties with exact knowledge on their [INCREMENT]-tetrahydrocannabinol (THC) and cannabidiol (CBD) content: Bedrocan (22.4-mg THC, <1-mg CBD; Bedrocan International BV, Veendam, the Netherlands), Bediol (13.4-mg THC, 17.8-mg CBD; Bedrocan International BV, Veendam, the Netherlands), Bedrolite (18.4-mg CBD, <1-mg THC; Bedrocan International BV, Veendam, the Netherlands), and a placebo variety without any THC or CBD. After a single vapor inhalation, THC and CBD plasma concentrations, pressure and electrical pain thresholds, spontaneous pain scores, and drug high were measured for 3 hours. None of the treatments had an effect greater than placebo on spontaneous or electrical pain responses, although more subjects receiving Bediol displayed a 30% decrease in pain scores compared to placebo (90% vs 55% of patients, P = 0.01), with spontaneous pain scores correlating with the magnitude of drug high (ρ = -0.5, P < 0.001). Cannabis varieties containing THC caused a significant increase in pressure pain threshold relative to placebo (P < 0.01). Cannabidiol inhalation increased THC plasma concentrations but diminished THC-induced analgesic effects, indicative of synergistic pharmacokinetic but antagonistic pharmacodynamic interactions of THC and CBD. This experimental trial shows the complex behavior of inhaled cannabinoids in chronic pain patients with just small analgesic responses after a single inhalation. Further studies are needed to determine long-term treatment effects on spontaneous pain scores, THC-CBD interactions, and the role of psychotropic symptoms on pain relief.
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In the last decades, a lot of attention has been paid to the compounds present in medicinal Cannabis sativa L., such as Δ ⁹ -tetrahydrocannabinol (Δ ⁹ -THC) and cannabidiol (CBD), and their effects on inflammation and cancer-related pain. The National Cancer Institute (NCI) currently recognizes medicinal C. sativa as an effective treatment for providing relief in a number of symptoms associated with cancer, including pain, loss of appetite, nausea and vomiting, and anxiety. Several studies have described CBD as a multitarget molecule, acting as an adaptogen, and as a modulator, in different ways, depending on the type and location of disequilibrium both in the brain and in the body, mainly interacting with specific receptor proteins CB 1 and CB 2 . CBD is present in both medicinal and fibre-type C. sativa plants, but, unlike Δ ⁹ -THC, it is completely nonpsychoactive. Fibre-type C. sativa (hemp) differs from medicinal C. sativa , since it contains only few levels of Δ ⁹ -THC and high levels of CBD and related nonpsychoactive compounds. In recent years, a number of preclinical researches have been focused on the role of CBD as an anticancer molecule, suggesting CBD (and CBD-like molecules present in the hemp extract) as a possible candidate for future clinical trials. CBD has been found to possess antioxidant activity in many studies, thus suggesting a possible role in the prevention of both neurodegenerative and cardiovascular diseases. In animal models, CBD has been shown to inhibit the progression of several cancer types. Moreover, it has been found that coadministration of CBD and Δ ⁹ -THC, followed by radiation therapy, causes an increase of autophagy and apoptosis in cancer cells. In addition, CBD is able to inhibit cell proliferation and to increase apoptosis in different types of cancer models. These activities seem to involve also alternative pathways, such as the interactions with TRPV and GRP55 receptor complexes. Moreover, the finding that the acidic precursor of CBD (cannabidiolic acid, CBDA) is able to inhibit the migration of breast cancer cells and to downregulate the proto-oncogene c-fos and the cyclooxygenase-2 (COX-2) highlights the possibility that CBDA might act on a common pathway of inflammation and cancer mechanisms, which might be responsible for its anticancer activity. In the light of all these findings, in this review we explore the effects and the molecular mechanisms of CBD on inflammation and cancer processes, highlighting also the role of minor cannabinoids and noncannabinoids constituents of Δ ⁹ -THC deprived hemp.
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Athletes involved in contact-sports are habitually exposed to skeletal muscle damage as part of their training and performance environments. This often leads to exercise-induced muscle damage (EIMD) resulting from repeated eccentric and/or high-intensity exercise, and impact-induced muscle damage (IIMD) resulting from collisions with opponents and the playing surface. Whilst EIMD has been an area of extensive investigation, IIMD has received comparatively little research, with the magnitude and timeframe of alterations following IIMD not presently well understood. It is currently thought that EIMD occurs through an overload of mechanical stress causing ultrastructural damage to the cellular membrane constituents. Damage leads to compromised ability to produce force which manifest immediately and persist for up to 14 days following exercise exposure. IIMD has been implicated in attenuated neuromuscular performance and recovery with inflammatory process implicated, although the underlying time course remains unclear. Exposure to EIMD leads to an adaptation to subsequent exposures, a phenomenon known as the repeated-bout effect. An analogous adaptation has been suggested to occur following IIMD, however, to date this contention remains equivocal. Whilst a considerable body of research has explored the efficacy of recovery strategies following EIMD, strategies promoting recovery from IIMD are limited to investigations using animal contusion models. Strategies such as cryotherapy and antioxidant supplementation, which focus on attenuating the secondary inflammatory response may provide additional benefit in IIMD and are explored herein. Further research is required to firstly establish a model of generating IIMD and then explore broader areas around IIMD in athletic populations.
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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.
Products containing cannabidiol (CBD) are now available throughout the United States, but their quality is oftentimes questionable. The CBD and Δ⁹-tetrahydrocannabinol (THC) content of 25 commercially available hemp oil products, obtained throughout the state of Mississippi, was determined via gas chromatography/flame ionization detection (GC/FID). These products were also analyzed for the presence of synthetic cannabinoids using full scan gas chromatography/mass spectrometry (GC/MS). Analytical findings were compared to label claims for CBD content. Product label claims for CBD ranged from no claim to 500 mg per serving; however, marked variability was observed between actual CBD content and claimed quantities. Of the 25 products, only three were within ±20% of label claim. Fifteen were well below the stated claim for CBD; two exceed claims in excess of 50%; and 5 made no claims. In addition, THC content for three products exceeded the 0.3% legal limit. Furthermore, four products—primarily marketed for vaping—were adulterated with synthetic cannabinoids. From this small, but diverse, sampling of hemp-derived merchandise, it appears that most product label claims do not accurately reflect actual CBD content and are fraudulent in that regard. Moreover, products that exceed legal THC levels may jeopardize a consumer’s employment status (i.e. failed “drug test”), while those adulterated with synthetic cannabinoids may subject them to serious adverse health effects. These findings argue strongly for further development of current good manufacturing practices for CBD-containing products and their stringent enforcement.
Introduction: Preparation for competitive contact sport has been extensively researched. There are, however, limited data to guide players as to how the demands of their sport affect the energy requirements of recovery. We aimed to provide novel data on changes in resting metabolic rate (RMR) in contact sport athletes and relate these to the physical demands of training and competition. Methods: Twenty-two elite professional Premiership Rugby Union players were recruited to the study. Indirect calorimetry (Vyntus CPX canopy; CareFusion) was used to measure RMR each morning of the competitive game week, in a fasted, rested state. External loads for training and game play were monitored and recorded using global positioning systems (Catapult Innovations, Australia), whereas internal loads were tracked using rate of perceived exertion scales. Collisions were reviewed and recorded by expert video analysts for contacts in general play (breakdown and tackle area) or the set piece (scrum or maul). Results: There were significant (P = 0.005) mean increases in RMR of approximately 231 kcal the morning after (game day [GD] + 1) and 3 d after the game (GD + 3), compared with the day before the game (GD - 1). The players were exposed to internal and external loads during the training week comparable to that of a match day; however, despite the equivocal loads between training and game play, there were no significant increases in RMR after training. Conclusion: The collisions experienced in rugby match play are likely to be responsible for the significant increases in RMR at GD + 1 and GD + 3. Consequently, the measurement of RMR via indirect calorimetry may provide a novel noninvasive measure of the effects of collisions. This study provides a novel insight to the energy requirements of recovering from contact sport.
Electronic cigarettes (e-cigarettes) were developed as an alternative method for nicotine delivery and had a significant surge in popularity. E-liquids are formulations used in e-cigarettes, and consist of a ratio of propylene glycol (PG) and vegetable glycerin (VG), a pharmaceutical and/or herbal remedy and, usually, a flavoring agent. Presented is the evaluation of nine cannabidiol (CBD) e-liquids from a single manufacturer for cannabinoids and other psychoactive compounds by Direct Analysis in Real Time Mass Spectrometry (DART-MS) and Gas Chromatography Mass Spectrometry (GC/MS). The analysis of these products resulted in the detection of CBD in all nine produces and the unexpected detections of 5-fluoro MDMB-PINACA (5F-ADB) in four of the products and dextromethorphan (DXM) in one of the products. The analysis of these products illustrates the potential quality control issues that can occur in an unregulated industry. CBD products are believed by many users to offer heath benefits, but the detection of a dangerous cannabimimetic, 5F-ADB, and DXM in these products illustrates the need for oversight.
The use of dietary supplements is widespread among athletes in all sports and at all levels of competition, as it is in the general population. For the athlete training at the limits of what is sustainable, or for those seeking a shortcut to achieving their aims, supplements offer the prospect of bridging the gap between success and failure. Surveys show, however, that this is often not an informed choice and that the knowledge level among consumers is often low and that they are often influenced in their decisions by individuals with an equally inadequate understanding of the issues at stake. Supplement use may do more harm than good, unless it is based on a sound analysis of the evidence. Where a deficiency of an essential nutrient has been established by appropriate investigations, supplementation can provide a rapid and effective correction of the problem. Supplements can also provide a convenient and time-efficient solution to achieving the necessary intake of key nutrients such as protein and carbohydrate. Athletes contemplating the use of supplements should consider the potential for both positive and negative outcomes. Some ergogenic supplements may be of benefit to some athletes in some specific contexts, but many are less effective than is claimed. Some may be harmful to health of performance and some may contain agents prohibited by anti-doping regulations. Athletes should make informed choices that maximize the benefits while minimizing the risks.