The Use of Nicotine, Painkiller and Cannabidiol Products

The Use of Nicotine, Painkiller and Cannabidiol Products and the Effects They Have on Sporting Performance

Abstract

The usage of Nicotine Products, Cannabidiol (CBD) and pain killers among the athletes of professional sports has reportedly increased. The research focused on an in depth investigation regarding usage, its reason, benefits and limitation associated with the aforementioned drugs. To internalize diversified variables associated with the usage of drugs among the athletes, the research integrated the usage of narrative literature review that focused on effects of nicotine, painkillers and CBD on athletes’ performance. The inclusion of diversified literature, from a variety of sources on athletes, the research concluded that nicotine absorbed through combustion e.g. smoking, was found to have negative effects on sporting performance. Whereas snus, another nicotine product was not found to carry these effects but instead aided in concentration and alertness. Painkillers showed effects of aiding sporting performance however, could be argued ethically and whether they just prolong the diagnosis of injury or not. Cannabidiol also was found mainly to aid sporting performance with little argument against other than potential drowsiness.

Key Words: Nicotine, Cigarettes, Vapes, E-cigarettes, Painkillers, NSAIDs, Sporting performance, effects, Cannabidiol (CBD).

Acknowledgements

I would like to thank my family and parents especially for always going out of their way to support me in anything I desire. 

1. Introduction

1.1 Background

In the domains of sports science and medicine, the use of drugs like nicotine, cannabidiol (CBD), and painkillers by athletes has generated a lot of discussion and interest (Kasper and Close, 2021). Even though these drugs are frequently used for their alleged advantages, there are possible side effects involved and ethical issues that need to be carefully considered. The inclusion of nicotine among the archery or shooting professionals is found to be common due to its ability to enhance motor skills and increase focus of the users. However, Bravo-Gutierrez et al. (2021) argued that the reduced lung capacity from nicotine has readily negated the aforementioned advantage with compromised stamina among the athletes. Similarly, CBD is widely known for improvement in sleep quality, alleviation of pain, and recovery from physical exercise. Contrarily, Leyk et al. (2023) argued that usage of CBD can disturb digestive system, appetite of an individual and cause a lower blood pressure; each of which are vital for maintenance of athletes’ health. 

The perception of usage of nicotine, pain killers, and CBD has readily enabled the performance of athletes to increase in an unnatural manner (Sansone et al., 2023). The usage of CBD is critically evaluated against high occurrence of positive doping results among the athletes (Williams and Nutbrown, 2021). Contrarily, Gustavsen et al. (2021) stated that the lack of information on CBD leads to their overdose without the consultation of a health practitioner. However, sporting industry is highly competitive with scientific advancements that has demanded elongated careers of sporting athletes. Meanwhile, each of the additive material incorporated in this research is scrutinised to shorten the span of career for an athlete resulting in performance depreciation in the long run. Zandonai et al. (2023) determined that a 22.7% of athletes used nicotine, from a sample size of 13804. Therefore, it is analysed that the use of nicotine is increasingly common among the athletes, with no particular method of nicotine consumption on focus. Contrarily, sporting boards are also concerned about the usage of the drugs which has formulated anti-doping agencies in all form of sports which regulates the environment of illicit consumption of drugs among the athletes.

1.2 Problem Statement

The existing researches have been increasingly focused to be against the usage of nicotine and painkillers while presenting a mixed review regarding the usage of CBD for athletes due to marginalising in athletes’ performance when analysed with a longer time interval (Zandonai et al., 2023; Sansone et al., 2023). However, the studies have widely ignored the perception of athletes in consuming the drugs and the factors associated with the benefit of consumption of nicotine, painkillers and CBD. Thus, it is important that a research in incorporated in which the benefits and limitation of each of the preceding drug is readily incorporated and the impact on athletes’ performance and longevity of their career is critically analysed for disruptive findings that can motivate or discourage the athletes from consumption of such substances. 

1.3 Research Objectives

The purpose of this piece of writing is to present a thorough analysis of the literature on the use of these drugs in sports, examining their properties, reasons for use, potential side effects and possible effects on sporting performance. Furthermore, the following objectives were formed to address the problem statement of the research:

1. To critically evaluate the usage of nicotine products and their side-effects on sporting performance. 
2. To critically investigate different types of pain killers along with their effects on sporting performance.
3. To critically understand the role of cannabidiol and its side effects on sporting performance.

1.4 Research Significance 

The study can readily enable coaches and athletes to learn about the advantages and limitations of usage of performance enhancement drugs which include painkillers and CBD, along with the habitual usage of nicotine among the athletes. The coaches can form an intervention for the athletes in case they develop addiction of nicotine, CBD or painkillers; otherwise, strategize an alternative method for athletes’ replacement to ensure standardisation of their respective team’s performance. Atakan (2012) identified that the athletes are widely unaware of the downside of CBD and are oversold on the advantages they perceive on the open sources. However, overuse of Tetrahydrocannabinol (THC) has shown increased involvement with positive doping results that leads to temporary or permanent ban on the athletes due to usage of performance enhancement drugs. Furthermore, limited involvement of health practitioners in prescribing CBDs has readily limited the approach of athletes in getting the drugs in a formalised manner that may not impact their long-term performance in sports. Therefore, the research can play a pivotal role as a foundational study for the use of nicotine, painkillers and CBD among the athletes.

2. Method and Search Strategy

2.1 Data Collection Method

For this research, collection of data from secondary sources was prioritised in the research in pursuit to ease the data collection process as the athletes are readily concerned about their public image and can raise significant ethical concerns for the study. Bell, Bryman and Harley (2022) determined that the secondary data collection strategy is incorporated by the studies which are reliant on already collected data to ensure an extensive dataset. The study incorporated use of secondary data which allowed the research to integrate extensive dataset and findings regarding the athletes and their usage of the aforementioned products. Nicotine products, painkillers and CBD are rarely used by athletes at the same time; therefore, usage of secondary data in this research enabled the study to have an acceptable approach towards data collection method which assisted the researcher in achieving the identified objectives of the study. 

2.2 Electronic Search Strategy

The electronic search strategy was extensively diversified for this research due to a highly specific field of interest, which were athletes’ usage of CBD, painkillers and nicotine. Since the results on Pubmed were limited in terms of specific research on athletes’ and nicotine; therefore, the research also incorporated the use of Google Scholar to ensure that a wide variety of dataset can be integrated into the research. Furthermore, advanced filters on Pubmed, Google Scholar and CINAHL were used to incorporate desired level of data set in this research. Boolean operators including “and”, “or”, and “not” were integrated in the electronic search strategy to narrow down the results of research papers according to the requirements of objectives of the research. It primarily enabled the research to have a focused search of articles which significantly eased the electronic search process for the researcher. Since Google Scholar is depicted as a fundamental researching tool for published articles, the results presented without usage of Boolean operators are readily diversified resulting in significant discrepancy for the researcher. Therefore, usage of Boolean operators was imperative for the researcher to continue with electronic search. 

Boolean operators were found to be significantly useful in searching through PubMed where search with term “Nicotine Usage” resulted in 357 results from 2020-2024. However, after adding a Boolean operator in the preceding term with “Nicotine usage and athletes”, the search results were limited to two articles only which enabled extensive efficiency for electronic search strategy. Similarly, search of “CBD performance enhancement” showcased results that amounted to 119 results from 2020-2024; however, after addition of “and” operator to incorporate the filter of athletes, the search result was narrowed down to 7 results which enabled the research to shortlist efficiently. Furthermore, a similar search strategy was incorporated for painkiller as well where the initial results that were incorporated in search of painkillers using “painkillers side effects” yielded 24759 results, meanwhile the search with Boolean operator “and” to filter side effects on athletes resulted in 235 results. 

2.3 Inclusion and Exclusion Criteria

The following table showcased the inclusion and exclusion criteria incorporated in this research to standardize and collect data:

3. Literature Review

3.1 Introduction

Usage of substance is highly common among the athletes to enhance their performance and longevity of their careers. However, the abuse of substance has led to marginalization of career spans of athletes resulting in abrupt ending of their career due to irrecoverable injuries. As a result, the following literature review, in line with the objectives of the research, is focused on secondary data’s finding regarding the impact of nicotine, CBD and painkillers on athletes’ performance while establishing an understanding regarding the forms of their usage in modernized environment. Furthermore, the literature review also displays the conclusive finding through evidence of studies regarding usage of aforementioned products. 

3.2 Nicotine Products

3.2.1 Understanding Nicotine and Nicotine-Products 

The usage of nicotine is commonly associated with chewable form of nicotine, cigarettes and cigar which are prevalently normalized by the society and has conditioned the individuals to embrace its acceptability despite the extensive research on negative impacts associated with unnatural release of dopamine through use of nicotine based products (Joseph & Pearl, 2024). Nicotine is the main psychoactive agent found in tobacco leaves and is highly addictive which has led to over 1 billion smokers across the world (Read et al., 2024). An estimated 1.3 Billion people use some form of tobacco product worldwide, making it the third most popular drug in the world behind general medicine and alcohol according to the World Health Organization (2024). Conventionally, athletes were fond of nicotine and were ambassadors of nicotine based products to enhance their acceptability. However, through disruptive research on the health outcomes of the individuals, specially the athletes, the acceptance of nicotine based products was significantly marginalised. Furthermore, increased marketing and perceived quality of nicotine products has also enhanced the prevalence of usage of nicotine products among athletes. 

Cigarette smoking is the main cause of preventable death amongst developed countries (Ren & Lotfipour, 2019); however, this does not mean that all forms of nicotine consumption will have the same physical effects on the human body. The use of snus is seen to be very popular among Scandinavian athletes across all sports, this may be due to the culture which embraces the use of snus (Sæbø, 2017; Zandonai et al, 2019). Football, as a sporting division, has been aggressively against the use of nicotine based products that they have banned the consumption of the product to facilitate the standardisation of advantage for all teams (Johnson, 2023). Since snugs are reported to calm the nerves of users and control their anxiety, it was determined as a performance enhancement drug. Whereas studies of Zandonai et al. (2019) and Joseph and Pearl (2024) have also been found to achieve the same results through an experimental research. Fixtures between Aston Villa and Arsenal along with Liverpool against Newcastle caught the act of 2 footballers, Bertrand Traore and Mark Gillespie inserting the snus pouches into their mouth while the cameras were on them (Taylor, 2023). However, the association of football across different states have failed to implement ban on a unanimous scale due to interference in personal life of the athletes. Contrarily, their main objective is to eliminate the usage of such products during the game. Meanwhile, private teams have been eagerly monitoring athletes’ consumption of harmful drugs by handing them a pre-agreed contract regarding their consumed item list. 

Following are the types of nicotine products that are widely consumed by athletes from a variety of sports:

• Cigarettes: A cigarette is a cylinder shaped rolled piece of tobacco which is consumed through lighting one end and inhaling the smoke through the other (Martin, 2023). From 2011 to 2022 the number of people who smoke cigarettes of all ages under 65 has dramatically decreased while the number of 65 year olds and above has remained relatively the same in the United States (Meza et al, 2023). 
• E-Cigarette and Vape: E-cigarette use has now surpassed standard cigarette use as the most popular way to smoke tobacco globally (Bravo-Gutierrez et al, 2021). Manufacturers claim that e-cigarettes are a safer alternative to smoking cigarettes and they are marketed as a way of cutting down on or quitting smoking (Rom et al., 2014). With the decrease in cigarette smokers this has largely contributed to the number of e-cigarette or vape users increasing. This was explained in a study carried out by Bandi et al (2023) who found that the number of e-cigarette users in the United States was largely made up of those who were formally cigarette smokers. In the same study it was found that 53% of e-cigarette users were people who had never smoked cigarettes before. 
• Snus and Nicotine Pouches: The overall research surrounding snus is a lot less than that around both cigarettes and e-cigarettes due to snus being a lot newer and not as popular. Snus, originating from Sweden and Norway, is a small pouch of smokeless tobacco which is usually placed under the lip against the gums (Clarke, 2019). The use of snus has been said to be another form of nicotine product which people use when trying to quit smoking as it is argued to have less side effects especially on the respiratory system as nothing is being inhaled into the lungs (Lund et al, 2010). 

3.2.2 Side-effects on Athlete’s Health

The negative effects of smoking have been thoroughly researched due to the long period of time which cigarettes have been around. Cigarette smoking is understood to cause diseases globally, specifically cardiovascular which is the leading cause of death worldwide and lung disease is also a risk due to the toxicity of the smoke inhaled (Munzel et al, 2020). Furthermore, tobacco smoke contains chemicals which harm the linings of the blood vessels causing an accumulation of plaque to build up which then can lead to atherosclerosis (Howard, 1998). The preceding condition can cause further problems as it restricts blood flow which can then increase the risk of peripheral artery disease, heart attacks and strokes which can directly impact athletes’ functionality and motor movements (Read et al., 2024). Furthermore, nicotine pouches and other products have also been found to increase both a person's heart rate and blood pressure which puts a higher demand on an individual’s cardiovascular system (Felber Dietrich et al, 2007). The study explains how the nicotine products contains mutagens and carcinogens which cause genetic changes and cancerous cell development. Lung cancer is not the only cancer associated with cigarette smoking however, others include cancer of the mouth, esophagus, pancreas, kidney bladder and cervix (Khani, 2018). 

Bravo-Gutierrez et al (2021) reviewed 79 studies conducted on the use of electronic cigarettes and found the results very similar to those of the persistent use of standard cigarettes. With negative effects on oral health involving oral cancer which led them to advise that these products be avoided. Although it is suggested that e-cigarettes have the same negative side effects as standard cigarettes this is not completely accurate. When analysing the effects of smoking versus vaping on the respiratory system, Darabseh et al (2020) discovered that the irritation of the bronchial tubes which cigarette causes was not present in the use of e-cigarettes. Furthermore, the same study did express how the prolonged use of e-cigarettes could lead to a lack of oxygen delivery around the body due to the increased levels of carbon monoxide leading to an increase in muscle fatigue. For the athletes, circulation of oxygen is vital for their movements and ability to have strong presence of mind regarding their game awareness (Dawkins et al., 2016). The preceding study revealed that the responsiveness level of athletes with active nicotine usage was slow compared to athletes with natural diet and healthier preferences. Furthermore, the mental health issues have become apparent, the rate of them involved with e-cigarettes is still not as high as those associated with standard cigarette smoking (Masaki et al, 2022). 

The use of snus has been promoted further in the nicotine industry as safer than using cigarettes and e-cigarettes due to the product not being a product of combustion however, that does not mean the product is completely risk free (Lee, 2013). Snus is a nicotine product which means it can be highly addictive similar to cigarettes, however, the main danger which has been discovered in the use of snus is the negative effect on an individual’s oral health (Hellqvist, 2012). Snus is consumed through places a pouch of nicotine against your gum usually under a person's upper lip, meaning long term snus use can result in gum recession and tooth discoloration along with an increased risk of leukoplakia (Ford and Rich, 2021). This constant exposure to the gums can also lead to an increased risk of oral cancer although the risk of cancer from snus is still greatly lower than those associated with smoking (Janbaz et al, 2014). Similar to cigarettes and e-cigarettes the content of nicotine within snus pouches can lead to an increase in a person’s blood pressure and heart rate allowing for them to become at risk from heart disease. However, this correlation between snus and heart or cardiovascular disease has been found to be very low (Hanson et al, 2009). 

3.2.3 Reason for Proactive Usage among Athletes

There are many reasons why people still smoke cigarettes despite understanding many of the negative side effects associated with the act. A study conducted by Ho, (1989) identified 4 main reasons for why people smoked cigarettes which included: social acceptance, addiction, pleasure and boredom. Smoking for social acceptance was touched upon by Masaki et al (2022) when they explained how both men and women aged between 17 and 24 thought smoking made them appear more acceptable, sophisticated and mature due to branding and prevalent misconception of the society. However, it is the acceptance aspect that leads to athletes frequent consumption of nicotine products with their existing mental state that does not allow to maintain required level of calmness for in-game decision making. Shiffman et al. (2015) discovered a distinct pattern among intermittent smokers (people who did not smoke daily). This pattern was that the intermittent smokers would rarely smoke in the morning and were more likely to smoke in the evenings of the weekend, amongst other people and including the presence of alcohol. This trend can be associated with social acceptance. 

For athletes, use of smoking was defended by being a stress reliever during pressure situations; however, Benowitz (2009) readily dismissed the stress alleviation capability of cigarettes by analysing the placebo effect a cigarette had on human mind. Fiddler and West (2009) conducted a survey where they found that enjoyment and stress relief were the 2 biggest factors that people gave as to why they smoked, with enjoyment making up 51% of the reasons and stress relief being 47%. Women gave the answer of weight control and stress relief more than men who gave the reasoning enjoyment more often. As mentioned, weight control can also be a reason for individuals wanting to smoke. Tomeo et al (1999) researched the use of tobacco amongst youth in America. The findings identified that both girls and boys contemplate smoking as a method of controlling their weight with the thought of experimentation being positively related to weight controlling behaviours.

Similar to vaping, the use of snus is seen as a less harmful way of consuming nicotine as opposed to smoking, which can be seen as a big factor in why people use it, especially those who are younger and have not smoked before (Tjora et al, 2020). A further reason for why people use snus is due to their addiction for nicotine, snus acts in the same way as smoking where the nicotine creates chemical releases of dopamine which is associated with making someone ‘feel good’ or ‘happy’ (Peloquin, 2018). Another similarity between snus and vaping which can cause people to use the product is the flavours in which it is available. Vedoy and Lund (2020), conducted research into whether flavours of snus should be limited in Norway. Their findings allowed them to come to the conclusion that flavours should be limited as the variety of flavours mixed with the nicotine can create a huge problem of addiction. 

3.2.4 Impact of Nicotine Product’s on Sporting Performance of Athletes

Smoking is massively discouraged in the sporting world due to its negative impact on athletes’ stamina. Through Tetelepta et al (2019) research, it was discovered that athletes who trained more frequently had a greater VO2 max; however, when comparing athletes who smoked, their V02 max results were significantly lower, regardless of how often they were training. Thus, smoking has a negative impact on athletes V02 max which is imperative for elite athletes as they need to be able to produce and use oxygen efficiently in pursuit to perform well for the duration of their sport (Daniels, 1974). The preceding study generated the results from secondary researches where data of diversified physiological differences were identified for athletes. Reduced pulmonary function has been found among smokers compared to non-smokers, according to Patersen et al. (2007) which supports findings of Tetelepta et al (2019) that smoking can reduce athlete’s ability to perform at high intensities for long periods of time. Telepatha et al. (2019) reached a conclusion through the incorporation of young athletes from the age of 18 to 25-year-old which is of high relevance for majority of athletes across various range of sports. 

Smoking has been found to negatively impact a person’s ability to build muscle due to it impairing the muscle protein synthesis and increasing the effect of myostatin which is the regulator of hypotrophy within the muscles of the body (Patersen et al, 2007). Similarly, to muscle growth smoking has also been found to negatively correlate with muscular strength (Kok et al, 2012). These 2 findings allow us to understand that smoking does not help athletes to grow the muscles they may need to perform in their sport, for example, trying to gain size to compete in rugby. It also impacts the maximal exertion in which an athlete can produce, for example, an Olympic weightlifter would not be able to lift the same amount of weight as they would if they were a non-smoker. Overall, smoking has a hugely negative effect on athlete’s with no evidence supporting any positive effects on athlete’s sporting performance.

The research surrounding snus shows positive findings in relation to snus use and; increased alertness and focus, reduced anxiety and helping with weight management. Snus has been said to help with weight control due to nicotine acting as an appetite suppressant (Simm, 2021) meaning athlete’s may be able to make weight in boxing for example, with the use of snus to help not over eating. Zandonai et al (2018), discovered that the use of snus during 30 minutes of exercise, increased muscular and cerebral oxygenation significantly, however this did not affect the athletes’ perception of being fatigued or their time till exhaustion results. This study explains that snus may help athletes be more awake and focused throughout their sport however, it will not impact their cardiovascular endurance in any positive way. A further survey conducted by Zandonai et al (2018), found that regular snus users reported a greater effect on their psychological state compared to occasional users. Furthermore, in the same research the results found that regular snus use may cause early cognitive improvement which in sporting terms may help athlete’s in decision making and concentrating under pressure. With the main risk of snus being in regard to people's oral health (Hellqvist, 2012), there is a lack of evidence showing that snus has any negative effects on athletes’ lung capacity or V02 max. This means that evidence shows it does not conclusively come with the risk of athletes not being able to carry out exercise for any less period of time to those who are non snus users, the same way it does with smokers versus non-smokers Zandonai et al (2013). Overall, snus does not provide the same negative effects on sporting performance compared to smoking.

3.3 Painkillers

3.3.1 Understanding Painkillers and their Variations

The use of painkillers is medically defended to overshadow the feeling of pain. However, it does not enable an athlete or user to recover from the pain without a therapeutic intervention. Contrarily, they are proved to be vital in easing the user with calmness and numbness around the injured region. In professional tennis 2.8% of players are reported to use analgesic while 54.2 professional football players used analgesic (Leyk et al., 2023). There are many different types of pain killers including nonsteroidal anti-inflammatory drugs (NSAIDs), acetaminophen, opioids, antidepressants, anticonvulsants, local anaesthetics and corticosteroids (Van Rensburg and Reuter, 2019). The effects of these are all similar in the fact that they are used to reduce the amount of pain people experience through blocking or reducing signals to the brain to reduce the perception of pain (Mischkowski et al, 2016). Leyk et al. (2023) determined that the active usage of muscles, accumulation of lactic acid and other inflammation that causes injury has readily inclined the athletes towards usage of painkillers. 

• Nonsteroidal Anti-inflammatory Drugs (NSAIDs): NSAIDs are better known as painkillers such as ibuprofen, naproxen and aspirin. The prostaglandin synthesis-related enzymes cyclo-oxygenase-1 (COX-1) and COX-2 are inhibited by NSAIDs, which have the analgesic, anti-inflammatory, and antipyretic effects that they do (Day and Graham, 2013). These forms of painkillers are usually used for mild to moderate types of pain, inflammation or fevers such as headaches (Jahnavi et al, 2019).
• Acetaminophen: Acetaminophen is better known as paracetamol and tylenol. These are a form of potent antipyretic and moderate analgesic which is believed to reduce pain through inhibiting the synthesis of prostaglandins in the brain (Toussaint et al, 2010). However, more research is needed to fully understand the way in which these painkillers really work.
• Opioids: Opioids are better in forms such as morphine, fentanyl and codeine amongst others. Opioids work through binding to the opioid receptors in the brain and spinal cord, thus blocking the transmission of pain receptors to the brain which reduces a person’s perception of their pain (Kanjhan, 1995). The use of opioids is usually for moderate to severe pain such as post-surgical pain, injury related pain or even cancer related pain (Levvy et al, 2019).
• Antidepressants: Examples of antidepressants include amitriptyline and duloxetine. Antidepressants work by altering the levels of neurotransmitters in the brain which can help modulate people’s pain perception (Khushboo et al, 2022). Antidepressants are commonly used for more chronic pain, in particular nerve pain (Verdu et al, 2008). 
• Anticonvulsants: Examples of antidepressants include gabapentin and pregabalin. These painkillers work by stabilising nerve activity through biochemical and electrophysiological processes which reduce pain signals (DeLorenzo, 1988). Anticonvulsants are used for neuropathic pain conditions such as post herpetic neuralgia (Backonja, 2002), which is the most common complication of shingles.
• Local Anesthetic: An example of local anesthetic is lidocaine. Local anesthetics can come in the forms of injections, gels, creams or sprays (Kumar et al, 2015). Local anesthetics work by blocking neuronal transmitters and stabilising electrically excitable membranes (French and Sharp, 2012), these work to numb specified areas of the body to reduce the feeling of touch. This form of painkiller is used for localised pain relief for procedures such as dental work, minor surgeries and some chronic pain conditions (Chou et al, 2016). 
• Corticosteroids: An example of this form of painkiller are cortisone injections. These injections have become a very popular form of painkiller which is used by athletes across different sports. Cortisol injections are a form of steroid injection, used to reduce inflammation and accelerate the healing process of injuries and joint pain in conditions such as arthritis or tendinitis (Fadale and Wiggins, 1994).

3.3.2 Side-effects of Painkillers on Athlete’s Health

Although painkillers are useful for short term benefits, misuse of them can lead to potential negative effects on the body (Eric, 2017). The body may also build up a tolerance to the painkillers if they are overused which is also a negative as the painkillers lose their desired effect of reducing pain felt within the body (Lauwerier et al, 2011). The main risks associated with NSAIDs is their gastrointestinal which can lead to issues such as stomach ulcers and bleeding (Laine, 2006). The results of the preceding study were generated through an investigation of patients’ data who actively used NSAIDs to treat their complications. Since athletes share the same physiology, the results of preceding study were implied on athletes as well. Additionally, there are risks which are more associated with the long term use of NSAIDs. These risks include an increased risk of heart attack or stroke (Pisano, 2016). However, the reasons behind NSAIDs and increased risk of cardiovascular events is not completely known and importantly, requires further research due to mortality rate associated with cardiovascular events (Park and Bavry, 2014). 

Hepatotoxicity, chemically driven liver damage is caused by acetaminophen which is found in painkillers (Guggenheimer and Moore, 2011). The preceding study also showed that the dosage amount between therapeutic and toxic doses was a very small margin, which if misused could lead to a drug overdose. Although opioids have been found to be very successful in treating acute pains, research has found that the drugs are very addictive with people becoming very dependent on them especially when exposed to them for a prolonged period of time (Højsted and Sjøgren, 2007). Darnell et al (2012), discovered that long-term opioid use in women came with many risk factors including, reduced fertility, higher cardiac risks and endocrinopathy. Although opioid use is often safe, death by respiratory depression caused from opioid misuse is still regularly reported (Dahan, 2010).

These forms of painkillers have the least known side effects which can be classed as deadly or overly harmful to the body, with potential side effects from use being drowsiness or dizziness (Bet et al, 2013). However, antidepressants have been recently understood to be linked with the potential risk of seizures, although the risk a person is at of experiencing one depends on their predisposing factors along with their dosage (Skowron and Stimmel, 1992). Newer generation antidepressants have also been found to have adverse effects by causing people to experience sweating and sleep disturbances along with nausea, diarrhea and more (Carvalho et al, 2016). Local anesthesia overall is considered to be very safe however, all procedures are never completely risk free so there are some potential risks or side effects which can occur from its use. 

Inconveniences such as pain at the injection side (if a needle is used for delivery), bruising or numbness beyond the desired area are all side effects which may occur from the painkillers use (Lalonde and Wong, 2014). Rarer and more severe risks associated with its use include systemic toxicity which is where if too much anesthetic is injected or the drug is injected into the blood vessel then dizziness and seizures can be caused or in severe cases, cardiac arrest (McCaughey, 1992). Side effects from corticosteroids are common in both short and long term use. Short term side effects include cutaneous effects (affecting skin structure and function), hypertension and hyperglycemia (Buchman, 2001). The long term effects of corticosteroid use include more serious risks such as osteoporosis and gastrointestinal, hepatic, and ophthalmologic problems (Buchman, 2001).

3.3.3 Painkiller Assistance in Athlete’s Performance

The reasons for use across all of the painkillers are the same and that is to reduce the amount of pain which a person feels whether that is due to injury, illness or in preparation for a medical procedure (Mischkowski et al, 2016). Depending on the pain severity or what the painkiller is treating then this will determine which of the products will be provided to an individual. This is a much more generalised reasoning for painkiller use as opposed to athlete specific. In terms of athlete’s, they may use painkillers for many different reasons including injury management. Injury management is where athlete’s will use painkillers in order to manage acute injuries (Overbye, 2021), whether this means a reduction of pain so they can continue or a painkiller to help them deal with the pain while they rest. Painkillers may be used by athletes to treat chronic pains such as arthritis in order for them to reduce the pain and continue to perform to their desired potential (Harle et al, 2018). Post-surgical pain is a further reason why athletes may use painkillers, as this can help reduce the pain during their recovery phase and rehabilitation (Zideman et al, 2018). 

Painkillers are very popular for use across many sports and age groups with even student athletes confirming that they had used painkillers in order to mask their injuries and continue to participate in their sport (Tricker, 2000). Since athletes aim to make most of their career, their reliance on painkillers to continue their run in the game is significantly high (Maurice et al, 2021). This means that the use of painkillers for athlete’s may be the only option they have in order to be able to perform in their sport even when being injured (Young, and White, 1999), this may just be so they can keep their livelihood and cannot afford to risk losing their job. Some people view the use of painkillers as the same behavior as doping where people are seeking a situational opportunity to gain an advantage (Melzer et al, 2022). Athlete’s also have to be very careful when using some painkillers such as opioids and corticosteroids are subject to regulations by some governing bodies (Preuss et al, 2019), which means misuse could result in an athlete receiving a doping ban. The doping bans were found to be on a list of Olympians which popularly included Adrián Annus, Geisa Arcanjo , and Olga Kuzenkova. 

3.3.4 Critical Review of Painkillers and Athlete’s Performance and Practical Application

Painkillers are determined to overshadow the feeling of pain and masking discomfort among the athletes which maybe caused the movement in an injured muscle (Young, and White, 1999). Painkillers can allow athletes to not be distracted by pain during their sport allowing them to fully focus on their task in hand and psychologically be fully invested in their performance outcomes (Taylor and Taylor, 1998). Furthermore, painkillers can help athletes achieve their desired full range of motion as they will not feel as much, if any pain from whatever injury they might have (Schneider et al, 2019). This will allow athletes to play to their full potential and not hinder their performance due to their injury. This is particularly important for athletes with joint pain or specific muscle pain which is required for their sport. For example, reduced knee pain for runners. 

However, painkillers could in fact also have negative effects on athletes' performance. The masking of injuries may be beneficial for athletes short-term but the use of painkillers could in fact hurt them more in the long run due to a delayed diagnosis of their injury (Mar et al, 2009), thus making the original injury worse. This is closely linked with the point that athletes could then have improper recovery due to not feeling as much pain (Goldsmith et al, 2018). This can cause athletes to be out of action for longer recovering from a more severe injury due to them trying to push through one that was less severe, causing more problems.

Some painkillers such as opioids (steroids) may affect a person's cognitive function (Chapman et al, 2002), which is imperative when playing sports. If an athlete's coordination or reaction time is affected, then this may cause them to make wrong decisions or not be able to perform to the best of their ability. Some painkillers can also cause a person to feel drowsiness and fatigue (Zlott and Byrne, 2010). This can hinder an athlete’s performance as they may not be able to perform correct decision making or last the duration of their sport. Similarly, painkillers such as opioids can disturb people's sleep (Onen et al, 2005), making them more restless and unable to get the rest required. Lack of sleep has been found to result in a person having a lower and less accurate cognitive function and performance (Fullagar et al, 2015). In a sporting setting, this again can cause incorrect decision making but also psychologically cause an athlete to not be fully invested in their performance.

3.4 Cannabidiol (CBD)

3.4.1 Understanding CBD and its Variations

Cannabidiol is more commonly known as CBD, is the non psychoactive compound which can be found in the cannabis sativa plant (Martinez et al, 2020). CBD is the non psychoactive compound which means it does not produce the ‘high’ effect which the other compound, tetrahydrocannabinol or THC, is commonly known for (Atakan, 2012). CBD is a disruptive new product which has grown more popular in recent years due to its potential healing and therapeutic benefits which can come in forms of capsules, oils, creams and liquids and more (Sherman and Chin, 2019). For athletes, the usage of CBD has been common for its unique healing process which enables them to recover from their energy faster and get on track again. Following are the types of CBD that are commonly found in the market:

• Cannabidiol (CBD) Oil and Spray: CBD oil is a liquid extract of CBD which is consumed through placing a specified amount of drops underneath your tongue for rapid absorption (Evans, 2020). There are variations to CBD oils as some oils can contain different ingredients. Full spectrum CBD oil contains cannabidiol, terpenes and negligible amounts of tetrahydrocannabinol (THC) (Vigil et al, 2020). 
• Capsules and Gummies: CBD capsules and gummies are edible forms of CBD which are either swallowed with a drink or chewed making for convenient dosing (Grogan, 2020). The effects of CBD gummies and capsules take longer to feel as they are ingested however, once the effects are felt they should then last longer compared to other products (Filipenko, 2022). 
• Cannabidiol (CBD) Vapes: CBD can be vaporized and inhaled with a vaping device, allowing for quick absorption and effects (Spindle et al, 2020). This form of CBD consumption goes straight to the lungs where it can be delivered into the bloodstream and offer fast relief (Varlet et al, 2016). Many types of vaping products are available such as CBD vape pens, CBD e-liquid, disposable CBD vapes and CBD vape cartridges (Choi et al, 2021). 
• Powdered Form: Powdered CBD is also known as CBD isolate and unlike other forms of CBD product, only contains cannabidiol (Marinotti and Sarill, 2020). Powdered CBD can be added to foods or drinks and then ingested through eating or drinking (Evans, 2020). 
• Topical: CBD can come in forms of balms, creams and lotions which can be applied to areas and absorbed through the skin for localized relief (Gomes, 2021).

3.4.2 Side-effects of CBD on Athlete’s Health

CBD oil has not been found to come with many severe side effects. Side effects such as dry mouth have been reported due to the CBD content decreasing the saliva production within the mouth (Scully, 2007). It can cause athletes to unnecessarily hydrate themselves which can increase their weight and restrict their mobility (Gustavsen et al, 2021). During research carried out by Dos Santos et al. (2024) into the adverse effects of CBD, one person withdrew from the group due to the effect of nausea which can happen especially if it is taken on an empty stomach in high doses.

CBD, when ingested has been found to cause a reduction in a person’s appetite, this can cause individuals to lose weight which can directly impact an athlete’s ability to perform as they require sufficient energy to optimize their capability during the time of the game (Pinto and Martel, 2022). This could be a negative or a positive depending on the individual and their goals. All of these ingested forms of CBD have similar side effects with one being the ability to elevate liver enzymes which can cause hepatotoxicity (Lo et al, 2023). People who consume these types of CBD products also have to be wary of the possible clash they can have with medication such as antidepressants. CBD has been found to help with conditions such as anxiety and depression. However, if mixed with antidepressants, it may cause an alter in the drug's efficiency and may also affect liver function (Swank, 2024). 

The side effects of topical CBD products are common with those of all topical, skincare or healing products known. The main potential side effect of topical CBD is the risk of skin irritation, this could be due to the CBD or the additives that may be found within the product not reacting well with the skin (Maghfour et al, 2021). Similarly, it is important to check the ingredients found in the product, in order to make sure there is nothing which may cause an allergic reaction (Baswan et al, 2020), as that can cause further irritation. Overall, the risks from topical CBD are very low (Xu et al, 2020), meaning it is a very safe product to use providing the product does not trigger any allergies. Topical CBD does not have the same potential side effects as other CBD products as it is absorbed through the skin (Makhakhe, 2022).

3.4.3 Understanding the Motivation of Athletes to use CBD

All these consumable forms of CBD have the same potential, positive benefits and reasons for use. The first reason athletes may use CBD products is due to its ability to help in relieving pain, whether this be chronic or acute (Boyaji et al, 2020). Another reason people may use CBD products is because they have been proven to help with athlete’s mental health issues such as anxiety along with helping reduce people’s stress levels, making them calmer (Williams and Nutbrown, 2021). Similarly, the preceding study found that CBD can help to create an increase of serotonin in the brain, which effectively can make a person happier and feel better in general. CBD can also be taken to help with a person’s sleep (Kuhathasan et al, 2019; Moltke and Hindocha, 2021). This is due to its ability to cause fatigue which is why many people choose to take the product at night for an undisturbed rest. 

Anti-inflammatory properties have also been found in CBD meaning it can help reduce inflammation and may help with certain illnesses or conditions such as arthritis (Atalay et al, 2019). Although THC has been used to treat seizure sufferers for years, studies suggest that CBD can have the same effects on treating seizures while avoiding the psychoactive effects of THC (Rosenberg et al, 2015). Overall, CBD has been found to have many benefits and there is still research being conducted to find out the full potential of the products as they are still fairly new. Topical of CBD can also be used to treat acute or chronic pain. The effectiveness of the topical CBD was proven by Eskander et al (2020), who found that hemp derived CBD cream provided significant pain and symptom relief for the case study who had chronic back pain. Topical CBD products have also been found to help with skin conditions when applied to such dermatological issues (Sivesind et al, 2022).

3.4.4 Impact of CBD on Athlete’s Performance and Practical Application

As mentioned CBD is still a fairly new product and as it comes from the cannabis plant some athletes may have been skeptical to use it due to not wanting to risk a doping ban, but now CBD has been cleared among professional athletes (Rojas-Valverde and Fellas-Campos, 2023). Many athletes have since been open about using CBD and the benefits they have felt such as Nate Diaz (Mixed Martial Arts), Kieran Kevan (Bodybuilding) and Paul Pierce (Basketball) (Howarth, 2023). CBD’s pain management effects may help an athlete perform without the distraction of pain allowing them to play to their full potential for the duration of their sport (Boyaji et al, 2020). As CBD can help with a person’s sleep (Kuhathasan et al, 2019). 

CBD can help an athlete’s recovery which can reduce their chances of injury and allow them to be fully energized to perform. CBD’s ability to help with stress and anxiety levels (Williams and Nutbrown, 2021), could help with calming athletes of nerves allowing them to make correct decisions and maintain steady breathing. Neuroprotective effects have been found in CBD allowing for better cognitive function (Callejas et al, 2018). This can further help with athlete’s decision making but also help them recover from brain injuries such as concussion quicker. In contrast, the fatigue effects of CBD may cause athlete’s to feel drowsy prior to competition if they take it in high doses (Gustavsen et al, 2021), this could negatively impact athlete’s performance as they could have reduced energy levels therefore, not being able to perform to their full desired standard. 

3.5 Chapter Summary

Despite the advantages portrayed in the literature review regarding usage of CBD, it was depicted that the lack of data and proven case studies regarding CBD has enhanced the commonality of the substance among the athletes. Meanwhile, the literature also criticized the usage of nicotine among athletes where the long-term impact of use of nicotine was found to be harmful for overall health of the athletes. Similarly, painkillers were depicted to be a short-term solution to ensure athlete’s availability at the time of discomfort. Therefore, each of the preceding substances were readily analyzed with their impact on performance of an athlete. 

4. Conclusion

Overall, from this literature review, the findings show that any form of combustion in the process of consuming nicotine has a negative effect on sporting performance due to mainly decreasing an athlete's V02 max and lung capacity. This means athletes cannot perform at high intensities for long periods. Snus however, has been found to not have these negative effects and instead may actually benefit sporting performance through increasing muscular and cerebral oxidation and improving alertness. This can help athletes in correct decision making. Painkillers are mostly good for an athlete’s sporting performance as they can reduce pain distractions allowing athletes to concentrate and provide them with full range of motion to carry out their needs. However, they could cause delays in diagnosis causing them to miss more sport in the long run. CBD can have positive effects on sporting performance, especially on cognitive function, which can help athletes with decision making. However, drowsiness may be a potential risk if taken in high doses, especially close to time of competition, this would negatively impact sporting performance. 

4.1 Areas for Future Research

After the completion of this research, future studies can identify the variables from findings section of the research and continue with: 

• Future research should look at the effects of snus on the cardiovascular and respiratory systems in detail in order to find out if it is really risk free.
• Future research could look at the possible effects of the 2 products working together to aid in pain relief.
• Future research could look at CBD and its impact on longevity of the career of an athlete while analysing the performance enhancement aspect of CBD that may unnaturally gain advantage for athlete. 

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