Weight Cutting in Combat Sports, An Open Debate.

A vital point to start this article is that there is no general consensus on how weight cutting affects a combat sport athlete. However, what is being projected to you here is the range of data based on some very good evidence. Combat sports refers to the class of contact sports where competitors engage in one-on-one combat with a specific set of rules with respect to the sport. Combat sports are typically divided into grappling, striking and mixed-style disciplines. In an effort to ensure competitors of a similar size, competition organisers divide competitors by their body weight. The presence of weight-cutting is almost omnipresent in modern combat sports as it is now common practice for athletes to attempt to gain a competitive edge and be paired with a smaller opponent by losing significant body weight in the days and weeks leading up to being weighed.

Methods of Weight Cutting
There are many different weight loss methods taken up by athletes before being weighed in for competition. The type of strategy employed is often dependent on a plethora of factors including the significance of the event, age and even the time between the weigh-in and the competition itself. The various types of methods include:

1. Energy intake restriction (gradual dieting and fasting)
2. Total body fluid reduction (restricting fluid intake, increasing sweat response - heated wrestling, plastic suits, saunas and spitting)
3. Pseudoscientific extreme/abusive medical practice (laxatives, diet pills, diuretics, enemas, sporting bulimia (vomiting)

Gradual dieting and establishing a caloric deficit is common among all combat sports. Various reports suggest that athletes utilise carbohydrate restriction more commonly than fat restriction. For shorter periods of time (less than 24hours) body mass reduction by athletes is usually taken up by body fluid manipulation. 45 to 75 percent of the average human’s body weight is made up of water. This is what allows for the manipulation of body fluid mass to accomplish losses of over 5 percent of an athlete's body weight in 24hrs. Here, the restriction of fluid ingestion and an increase in thermal strain to induce sweating appear to be commonplace in a wide range of combat sports. The potential methods that athletes use to induce thermal strain is important here. Further, there is another practice known as water-loading wherein athletes reduce sodium and overdrink water in an effort to trigger a ‘flushing mode’ of excessive urine production to maximise weight loss.

Weight Cutting and Athlete Performance
It needs to once again be brought into attention that there is no common consensus and there are arguments that favour both sides of the topic which is introduced next - the effect of weight cutting on the athlete's performance. The relationship between weight cutting and performance is murky at best. There is research suggesting that weight-cutting practices negatively influence repeat-effort performance while at the same time, other research indicates no impact on repeat-effort, aerobic, and anaerobic performance. Among these levels of gray, however, it is clear that when larger magnitudes of weight are lost rapidly with thermal strain, high-intensity exercise performance is impaired and the similar magnitude of weight cut over multiple days using a combination of methods such as food restriction and body fluid manipulation does not show the same negative effects.

Mechanisms by which Weight-Cutting affects Athletic Performance
Reduction in energy intake reduces glycogen levels in the body. This lowered level of muscle glycogen results in impaired excitation–contraction coupling in the muscle cells that induces easy muscle fatigue. When taken up for longer periods of time the body's carbohydrate and lipid metabolism is affected. The body becomes more reliant on ketone sources of energy. This adaptive response makes the body reduce the expression of aerobic glycolysis enzymes. This is seen to affect high-intensity exercise. With respect to dehydration as a strategy of weight cutting, different physiological changes are observed. Dehydration via sweat loss leads to a reduction in blood plasma and thus total blood volume as blood plasma makes up 55 percent of blood volume. This change would impair cardiovascular function, muscle blood flow and thermoregulatory capacity. Further, acute dehydration alters the body's electrolyte concentration and this influences the cell’s fluid balance, metabolism and even impairs neuromuscular functions and the maintenance of the electrochemical potential. Despite this, there are no relevant sources of information that investigate whether combat athletes are fighting in a state of complete ketosis. Similarly, given the recovery period between weigh-in and competition can be as long as 24 h it is unclear if a reduction in blood plasma will remain. Lastly, research investigating dehydration and its effect on membrane electrochemical potential has been mixed with studies observing a negative, or no impact.

Conclusion
As mentioned earlier, by competing in a lighter weight class, the athletes are at a theoretical size advantage. The present problem today is that almost everyone takes up weight cutting. So now the interesting predicament is that athletes have to lose weight to participate in a lower weight class to be able to participate with competitors the same size as them. This makes the process a vicious necessity now. Hence, in my opinion, the actual sport is only one part of the challenge and the weight cutting is an extra facet that the athletes must overcome to be successful in their sport.