Introduction
During the COVID-19 pandemic, many sports events and training courses have peen put on a pause, which meant that athletes got less training. The sudden changes in activity could influence their physical fitness, either positively or negatively, or both to some degree. The purpose of this literature review is to determine the influence of the COVID-19 lockdown on physical training practices implemented by Judo athletes. The review is divided into three topic sections, including Physical Fitness and Physical Activity in Judo Players, Weight Management in Judo Players, and Barriers and Motivators for Maintaining Physical Fitness in Judo Players. The scope of the literature review covers articles published only in peer-reviewed journals such as Journal of Environmental Research and Public Health, International Journal of Sport Nutrition and Exercise Metabolism, Journal of Strength and Conditioning Research, British Journal of Sports Medicine, and others. To ensure that the literature review is relevant to the current context, no studies published later than 2017 were included.
Physical Fitness and Physical Activity in Judo Players
In judo players, the emphasis is placed on achieving high levels of physical fitness and physical activity to guarantee success. In their study, Quintero et al. (2019) discuss aspects of judo sport, such as physical fitness and technical aspects. Even though only 15 subjects were used for the study, other criteria for assessing muscle power, aerobic power, and anthropometric measurements met the criteria of analyzing physical performance and body composition among Judo players. Many World and Olympic male athletes usually have less than 10% body fat (Quintero et al., 2019). These athletes must have a lower body fat percentage than males of similar age and height. A focused Judo athlete must maintain aerobic training and sound nutrition principles to maintain a steady 7 to 10% body fat (Quintero et al., 2019). High intense training causes a decrease in body fat due to intense exercises before the last weeks of the onset of competition.
The findings by Quintero et al. (2019) were supported by Berkovich et al. (2019) who examined the rapid weight loss technique used by many judo athletes. The study also examined the attitude and perception of coaches regarding RWL among judokas. Some judokas undergo weight reduction through calorie reduction to choose a lightweight class to have an advantage over some athletes in a particular weight category. Berkovich et al. (2019) used structured questionnaires and recommended that judokas be supervised under the weight loss program; the athletes should also practice a gradual weight loss program through dehydration and increased physical activity. Based on sex, female judo athletes’ fat percentile in the body is higher than their male counterparts.
Draing from the implications of research by Quintero et al. (2019) and Berkovich et al. (2019), it is possible to suggest that the level of competition can also influence the body fat composition as the national-level judokas have been found to have a higher fat percentage than those competing at the international level. Judokas who performed in the Olympic Games had a lower body fat percentile than those who participated in the competition at the university level. To sum up, the fat percentage decreases among the athletes with increased competition level intensity. Nationality also plays a role in variations observed in body fat weight percentage among the judokas. Quintero et al. (2019) used descriptive statistics using software SPSS 17.0. Researchers concluded that Colombian judokas showed a higher body fat percentile than those in Canada, while those from Turkey showed higher body fat than those from Colombia.
Besides addressing the body fat and muscle percentages in judo athletes, scholars have also paid attention to maximal oxygen uptake (VO2max) as an important measurement in assessing the aerobic capacity of judokas. For example, in their study, Dey et al. (2018) used a population sample of 20 participants to examine young judo players’ aerobic and anaerobic fitness. Dey et al. (2018) study was relevant to judo sport as it helps understand judokas’ aerobic and anaerobic physiology. It showed that male judo professionals have a VO2max of about 57 ml/kg/min while females have an average VO2max of around 47ml/kg/kg. The importance of the measurement was also supported in the study by Antunes et al. (2022) who aimed to determine whether the vasted body oxygen uptake and hemoglobin/myoglobin deoxygenation kinetics at high-intensity exercises were linked to greater upper-body performance. It was found that low and medium-weight judo athletes have a lower VO2max than their heavyweight counterparts.
Besides maximal oxygen uptake, scholars have also investigated maximal strength as the greatest torque that a muscle or a muscle group can produce at a certain velocity. Dalui and Bandyopadhyay’s (2018) study focused on assessing the physical fitness and physiological profile of Indian judokas. Sixty participants were used in the study to determine the maximal strength of Judo athletes (Dalui and Bandyopadhyay, 2018). Male judo athletes wer found to have a higher isometric strength than their female counterparts. Drawing from these findings, it can be hypothesized that higher intensity training of female athletes can help reduce this gap. Moreover, to achieve maximum outcomes, stress management for Judokas is crucial, especially in those who lose weight before the competition.
Considering the fact that maximum strength is achieved when multiple other factors come into play. Specifically, heart rate at rest could be used as a good indicator of strength. Julio and Franchini’s (2021) study discussed important physicological components in judo sports. They reported a mean heart rate of around 180 bpm during the competition, approximately 90% of HRmax. HRmax of males in the contests is about 190 bpm, slightly less than that recorded in females (Julio & Franchini, 2021). Heartrate has often been used to quantify exercise intensity in judo training. A physically fit Judo player must have cardiac efficiency to maintain the high cardiac output required during a Judo match. There should be a proficient exchange of air at the capillary alveolus to reduce the lethargy that the athlete may be prone to. Drawing from the findings of Julio and Franchini (2021) and Dalui and Bandyopadhyay (2018), it can be stated that regular involvement in training usually enhances the cardiorespiratory efficiency of an athlete.
Hall (2021) supported the findings of Kumar (2018) by showing that judo training could significantly help burn cholesterol, which can get deposed in the blood vessels. Fat deposition in intima has a high potential risk, especially in coronary and cerebral vessels, leading to myocardial infarction and stroke (Hall, 2021). Judo players have a reduced risk of suffering from hypertension because of a reduction in the blood vessels’ luminal narrowing, leading to increased blood pressure. Increased body fat is associated with reducing insulin sensitivity; thus, Judokas exercising to reduce their body fat percentile decreases their risk of suffering from diabetes mellitus, a finding consistent with Kumar (2018). Athletes metabolize the glucose they consume, and therefore, they have improved control of blood sugar through expanding in high-intensity exercise.
Therefore, after reviewin the literature, it can be concluded that judo exercising has a positive the physical fitness and physical activity in athletes. Drawing from the studies, it can be hypothesized that training judo players significantly reduces the percentile of body fat percentage. Specifically, it was found that in Caucasian Judo athletes, the percentil of muscle was whigher while the percentile of fat was lower compared to non-athletes. Moreover, to achieve maximum outcomes, stress management for Judokas is crucial, especially in those who lose weight before the competition. The regular involvement in training usually enhances the cardiorespiratory efficiency of an athlete. Attaining fitness in judo sports is also crucial in preventing an individual from getting lifestyle-associated diseases such as diabetes and hypertension. Judo exercising reduces the risk of an individual suffering from lifestyle-associated diseases by assisting in regulating blood glucose and cholesterol.
Weight Management in Judo Players
Before each tournament, Judo athletes undergo several weight-loss interventions to find the most appropriate competitive category. The study by Lakicevic et al. (2020) examined the possible effects of RWL among judokas. The study recommended that it was crucial to determine the minimum athletes’ weight to participate in sport to avoid the detrimental effects of RWL. The process of weight control has been developed to ensure that everyone gets an equal chance to compete against athletes with similar parameters. Most judo athletes use tactics that cause rapid weight loss (RWL) preceding a competition. Higher chances of success have been detected in athletes who can los more weight during RWL. Weight-loss strategies have become prevalent among the Judokas, ranging from 53% to 100% (Lakicevic et al., 2020). According to Lakicevic et al. (2020), 90% of males and females were already on RWL practices before the commencement of the official weight-loss sessions. Because most judokas cannot maintain their body weight after the competition, they often regain it; thus, they must reduce it to re-enter the match later.
The Judokas use many methods to make them lose significant weight in short duration to achieve the desired weight. Such strategies can include but are not limited to missing meal time, decreasing the intake of fluid, using rubber suits for training, as well as increasing the intensity of exercises. Beyond the recommended guidelines, these athletes also drastically use illegal pharmaceutical drugs to lose weight. These athletes are weight cyclers because of weight loss and weight gain patterns. On the greater scale, the Judokas often lose approximately 2 to 10% of their body weight preceding a competition, primarily in 2 to 3 days preceding the weight-in session (Lakicevic et al., 2020). When it comes to the influence on RWL on the endocrine system, a positive relationship between dehydration levels and the concentration of cortisol was found. Still, a negative correlation is established between dehydration and testosterone level.
RWL was also found to affect important biomarkers of athletes, such as serum total cholesterol, free fatty acids, triglycerides, phospholipids, glycerol, low-density lipoproteins, apolipoproteins, and cholesterol within the human body. In their study, Lakicevic et al. (2020) found the importance of correlating the physicological changes of important biomolecules before, during, and after a judo match. It showed that triglycerides and fatty acids significantly decreased after the RWL, but most of the other biomarkers were unaltered. Ammonia and urea concentration increased dramatically in the follow-up after the RWL program. RWL group also showed a significant decrease in insulin production, and the hormone level increased markedly 10 minutes after the competition (Lakicevic et al., 2020). The levels of glucose in the blood significantly increased only in the weight loss group’s third measurement.
While Lakicevic et al. (2020) suggested that hormone levels influence either weight loss and weight gain, more researchers explored the role of hormones. For example, as found by Roklicer et al. (2020), the increased ACTH was associated with the RWL group; this augments cortisol release, which is crucial in managing the stress induced by weight loss. A significant increase in the serum aldolase was noted during the RWL; however, the increase remains within the normal range, unlike CK and Mb whose increases go beyond the normal ranges (Roklicer et al., 2020). Blood hemoglobin level remains the same during the exercise-only period but considerably increases during the RWL phase.
The relationship between weight loss and the psychological well-being has also been noted by researchers. Brandt et al. (2018) used a population sample of 12 athletes to show the effect RWL had on judokas’ mood changes. The study revealed that RWL in athletes was associated with being more confused 30 days before the competition. Thus, judo athletes reported significant mood alterations in their daily life. In an investigation, RWL athletes were asked to complete a questionnaire prior and befor an intervention with six mood states: confusion, fatigue, anger, vigor, fatigue, depression, and tension. The associated findings were that anger, tension, and confusion were intensified among the judokas who chose the RWL intervention programs (Brandt et al., 2018). Depression remained unchanged, but an associated decrease in vigor was noted. The feelings of anger were highest on the morning of the competition and became insignificant after the match. Importantly, adequate nutrition was found to be crucial for an athlete undertaking an exercise.
RWL is also linked with an increased risk of injuries. Lakicevic et al. (2020) stated that a reduction of 5% of body mass impacts muscle contraction patterns and metabolism. Judokas who eliminated more than 5% of body mass had a greater risk of suffering injuries during the match than those who lost less than 5% of their body weight (Lakicevic et al., 2020). The short-term hypohydration in the weight loss program can cause a disturbance in the body’s homeostasis. It may enhance a shift in the electrolytes between the extracellular and the intracellular fluids. There is also an indication that dehydration affects mental fatigue by enhancing the perceived exertion during exercise and harmfully influencing the mood status. Many studies have that salivary osmolality is a good indicator of assessing the patient’s hydration status.
When athletes deprived themselves of food to lose weight, it was shown to result in adverse consequences for physical wellness. For example, the study by Anyżewska et al. (2018) focused on evaluating the impacts of RWL among athletes by using 62 participants. The body was deprived of carbohydrates, proteins, vitamins, and other essential minerals (Anyżewska et al., 2018). The deprivation of food can cause deficiency in important minerals such as calcium, magnesium, and potassium, which may be associated with muscle problems such as weakness and irregular contractions. Deficient Vitamin D in the body may affect bone strength and cause failure to attain optimum muscle performance; these properties are crucial in judo sports.
The study by Anyżewska et al. (2018) calls for exploring eating disorders among judo athletes. Using the questionnaire method, Maffulli (2017) explored the ways which were appropriate in assessing RWL in different countries. Eating disorders are more prevalent in males than females, and the enhanced risk of acquiring these disorders is undertaking a weight-dependent sport. The prevalence of RWL judokas in England is approximately 84%, while those in Brazil are close to 89 %; these values are high and call for immediate attention (Maffulli, 2017). Maffulli (2017) showed that many athletes lost close to 2.5 kgs about five times in a season in Brazil. Some athletes use severe RWL methods such as diuretics, laxatives, and vomiting agents; this may adversely affect their health status. The findings were consistent with the research by Anyżewska et al. (2018) show that 68% of the athletes examined stated they had ever undergone the RWL, and the athletes could reduce approximately 7% of therir body weight in 3 days. This considerable weight loss is enormous compared to the duration; thus, it causes a health concern. Therefore, in some instances, the weight reduces, but the amount of adipose in the body remains the same, suggesting that the weight loss was a consequence of loss of lean body meat and dehydration.
Education would significantly reduce the health effects among judo athletes as most engage in RWL practices because of a lack of knowledge. In the current study of Maffulli (2017), an average knowledge score of approximately was obtained, indicating that the judokas have a moderate understanding of the consequences of RWL. Current literature data provides the fundamental basis that the RWL procedures may affect the patient acutely and chronically (Lakicevic et al., 2020). Carbohydrate intake must be stressed, and most of the weight loss should originate from fat substrates. Evidence shows that intermittent fasting can help lose body weight while maintaining muscle mass. Because RWL is performed in other combat sports such as boxing and wrestling, more literature reviews should be published to determine the impact of RWL in these sports. RWL could have considerable health impacts on an individual, and thus, athletes must be discouraged from engaging in unrecommended weight-loss strategies.
From the review of literature on the weight management among judo athletes, several important findings should be noted. Because most judokas cannot maintain their body weight after the competition, they often regain it; thus, they must reduce it to re-enter the match later. Beyond the recommended guidelines, these athletes also drastically use illegal pharmaceutical drugs to lose weight. Importantly, adequate nutrition was found to be crucial for an athlete undertaking an exercise. There is also an indication that dehydration affects mental fatigue by enhancing the perceived exertion during exercise and harmfully influencing the mood status
Inadequate food intake in RWL causes a deprived consumption of minerals while hormone levels fluctuations also played an important role in weight fluctuations.
Barriers and Motivators for Maintaining Physical Fitness in Judo Players
Personal and environmental barriers may prevent one from actualizing and sustaining physical fitness. There are multiple individual barriers, such as psychological feelings by an athlete that he has insufficient time to undertake the sporting activity. Hickey and Mason (2017) provided an extensive literature analysis of the population’s factors that determine exercise rates. They argued that age influences the rate of exercising as older athletes may develop a reduced tendency to exercise because of easy fatiguability. Athletes may also feel that the exercise is inconvenient, as some exercise training machines require heavy capital to purchase.
Still, injuries may hinder attaining or maintaining physical fitness under personal factors. Judo is a highly intense game; injuries may easily result. Chang et al. (2019) focus on important mental and psychological issues that affect athletes. The literature is relevant to the judo sport as it helps the athletes note how different psychological issues impact their performance. An athlete who has suffered multiple injuries may quickly leave playing the sport, preventing him from achieving and maintaining physical fitness (Chang et al., 2019). COVID-19 disease affected many people globally, including athletes, as the lockdown was enforced in many countries. Lim and Pranata (2020) help individuals understand the impact of COVID-19 on sporting activities. The athletes were forced to stay indoors, which negatively affected their level of physical fitness (Lim & Pranata, 2020). Their mental health was adversely affected as they could not participate in exercise activities because of these restrictions.
Congenital and acquired deformities may also play a role in preventing one’s participation in judo. Moore et al. (2020) is an embryology textbook relevant to all medical practitioners and interested individuals to explain different congenital abnormalities. For instance, a person with congenital talipes equinovarus may not have a chance to participate in the sport even if he is interested in the game (Moore et al., 2020). A person born with a deformity of the hands or an amputation may be compromised to participate in the game effectively. The above individuals may get it hard to match the demands of the physical exercises during training, and thus they have a greater risk of being poorly fit. They may thus have an associated risk of suffering from associated lifestyle disorders such as diabetes and hypertension because of little or no exercise.
Drug and substance abuse may negatively impact the attainment of physical fitness among the judokas. McDuff et al. (2019) is an appropriate literature journal that can help sports personalities understand the impact of drug abuse among athletes. The authors use the existing evidence on drug abuse to explain its impact on athletes. The drugs directly affect the body system by causing injuries to many organs (McDuff et al., 2019). For example, cigarette smoking negatively alters lung function, and thus these athletes may develop obstructive and restrictive lung diseases or lung cancer. The lung and heart are vital organs in a person undertaking high-intensity exercises. Therefore an individual with lung function disorders may discover it hard to cope with the demands of these exercises.
An individual’s health status is one of the most significant barriers, as some diseases may impede one from performing physical exercises. Hall (2021) can help an individual effectively understand the physiological determinants of exercising. Cardiorespiratory disorders may hinder the performance of specific physical activities (Hall, 2021). A person with myocardial infarction may not perform some exercises because of angina pain in the chest. An athlete suffering from an acute respiratory disorder may find it hard to actively participate in the high-intensity activities undertaken during judo training and gaming sessions. A diabetes mellitus athlete may prefer to withdraw from the training because of the fear of injury, as the condition is associated with poor wound healing.
Several environmental factors, such as crime and pollution, determine the adherence to the exercise schedule. Gashaw and Yitayal (2019) extensively researched air pollution’s impact on athletes. It appropriately fits to be used by sports personalities to understand how pollution impacts their health. Environmental pollution may deter people from following the exercise program as pollution may significantly alter their normal health status (Gashaw & Yitayal, 2019). Insecurities within an area where the exercise intervention is undertaken may negatively impact people adhering to the exercise programs. Inaccessible venues will hamper the efforts of those wanting to engage in the sport to attain physical fitness. Good security and minimized environmental pollution will improve the devotion to the exercise program positively correlates with proper physical fitness.
However, an athlete’s health may also positively impact the incorporation of the judo game. An athlete may attend the training sessions of the game if they have the primary goal of staying physically fit. Mohan and Damjanov (2019) is an acknowledged textbook of pathology that can be used to understand various pathological and physiological concepts. A person who began the judo exercises before getting the lifestyle diseases may be motivated to continue gaming to avoid acquiring these diseases (Mohan & Damjanov, 2019). The high-intensity judo exercise is associated with a decreased risk of lifestyle-associated diseases like hypertension and diabetes (Mohan & Damjanov, 2019). The exercises burn excess cholesterol, thus reducing one’s risk of suffering from hypertension and stroke.
Social bonding may be a substantial factor that motivates athletes to follow the training program. Lloyd et al. (2019) discuss extensively various aspects concerning physical exercise among young people. One of the primary reasons athletes enjoy exercising is their social interaction during the training session (Lloyd et al., 2019). This interaction is crucial to their mental health status as it assists them in relieving other psychological stresses they may be having. The reduced psychological stress is correlated with decreased risk of lifestyle diseases such as hypertension. Parental and social support have a significant role in promoting or discouraging participation in judo games.
The level of education may prove to be a significant factor in determining one’s motivation to engage in exercise. Magee et al.’s (2017) relevance in the judo sport is demonstrated as it used 430 participants to assess the knowledge level of appropriate nutrition among the athletes. If one does not exercise, knowledge of the health consequences one faces motivates them to engage in activity to attain optimal fitness (Magee et al., 2017). Ignorance and low knowledge levels are the potential causes of people becoming physically unfit because of lack of exercise. People with good education levels will also be unlikely to engage in unhealthy practices such as RWL, which has detrimental consequences on their health. Good nutrition may also motivate one to aim at achieving physical fitness. After undertaking the exercise intervention, positive results may encourage one to comply with the practice strictly.
To conclude the review of literature on the barriers to physical fitness maintenance in judo players, it should first be mentioned that as with any sport, judo can become boring to some people, thus, they may choose to drop it. Failure to set and achieve goals, whether due to trauma or emergenies such as COVID-19 can cause strain on the players who may have no motivation to continue. Also, judo is a game that requires an athlete to be physically fit without any deformity to thrive in sports effectively. Physical health status, including respiratory well-being, the diagnosis of diabetes mellitus, and environmental factors can also significantly limit atheletes’ capacity to high achievement in judo. From the sociological perspective, the educational status and social skills also help determine success in maintaining success in judo.
Conclusion
To conclude, an athlete with good physical fitness has increased efficiency in performing sporting activities and reduced instances of injuries. Judokas attain physical fitness through their dedicated efforts in training. The current state of literature on the topic is adequate because the issue is quite narrow. There are studies dedicated to both physchological and physical health of judo athletes, suggesting that strong mental health leads to better outcomes in sport. The research gap, however, is associated with the need for more substantial scientific evidence about why the athletes love the practice is lacking. Besides, more research is needed as to the influence of education and social status on helping to maintain judo practice. Some exercise determinants are COVID-19, low knowledge level, individual motivation, athletes’ health, and environmental factors such as pollution and drug and substance abuse.
Despite the findings about the impact of RWL on judokas, the research gap is concerned with determining athletes’ minimal competitive weight for health prioritization. The prevalence of RWL among the judokas, exercise patterns and barriers faced by the athletes, such as the COVID-19 pandemic, leads to the interesting study of the chosen topic. Future studies may encompass more analyses of the relationship between mental health and judo performance after the COVID-19 pandemic because coronavirus has shown to impact the psychological well-being of people.
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