Weight class divisions exist so the matches are more equitable in terms of body size, strength and agility. However, many athletes in different combat sports acutely reduce body mass in an attempt to get an advantage by competing against lighter, smaller and weaker opponents.
In modern MMA, cutting weight for many athletes has seemingly become more of a strongly advised requirement than an advantage. This is due to that in modern MMA most athletes cut weight to get into a lower weight class, especially when the athletes neutral weight lays right between two weight divisions or just slightly above one.
There are also other factors such as the potential energy loss from cutting weight that can directly affect performance. Therefore, in most cases the advantage of weight cutting becomes less prevalent and balances itself out. Although there are successful cases of athletes gaining weight to get into a higher weight class this section of the paper will more focus on the methods used in weight cutting and the potential benefits and harms of them.
In professional MMA weigh-in (where the athlete’s weights are taken to make sure they are within their weight category) happens around 24 hours before the fight itself This potentially changes the degree of how much an athlete can cut weight before the fight compared to an amateur combat sport event that can have the weigh – in on the same day of the event.
Weight cutting strategies have been in literature usually divided into two categories; Neutral/Gradual Weight Loss (NWL or GWL) and Rapid Weight Loss (RWL) (Franchini et al. 2012a, Coswig et al. 2015). RWL has been characterized by reductions of 5 to 10%+ of body weight in less than a 3-7 days.
Many methods have been utilized by athletes during a weight cut week including; reduced liquid/energy (Carbohydrates & fat) ingestion, saunas, heat suits/bag or fasting.
Aggressive methods like specific diuretics, laxatives and vomiting have also been reported but are rare. It is important to note that diuretics are forbidden by the World Antidoping Agency.
The scientific community seems to lean more towards that RWL methods are very likely to cause some form of negative implications on physical performance. The negative effects that have been demonstrated in studies include: decreased short-term memory, concentration, lower lactate levels (less efficient anaerobic system), decreased testosterone/cortisol ratio, specific muscle damage markers and dehydration.
One study on 40 MMA athletes looked at the effects of RWL on hydration markers 22 hours after weigh-in and 2 hours before the bout. At this point the MMA athletes had gained approx. 4.4% of their body mass back (around 2 – 2.5 kg). Urine specific gravity markers (used to measure dehydration) significantly reduced in 39% of participants indicating serious dehydration just before the bout (Jetton et al. 2013).
It is important to note that unfortunately this study did not report the average amount of weight dropped during the RWL process, so strong conclusions are hard to draw. Another study on MMA athletes showed that using RWL methods to drop around 10% of mass increased the risk of muscle damage markers and catabolic expression pre- and post-bout.
One study on 7 experienced Judo athletes showed no effect on anaerobic performance markers (Wingate test) after a 5% reduction in weight within 5-7 days using own selected RWL methods. The even more intriguing fact was that weigh in was only 4 hours before performance tests. It was also reported that the test group consumed large amount of carbohydrates and food after weigh – Another study with nearly the exact same set up (5 % reduction, 4-hour recovery window) with 18 combat sport athletes showed no effect on high intensity performance with own
selected RWL methods. This study also found no difference between experienced and unexperienced athletes.
In regard to the magnitude of weight loss, Franchini reported that in Judo and Wrestling a considerable amount of athletes (40%) reduce 5-10% of body weight and many athletes reported more than 10% weight cuts.
There seems to be adequate evidence on positive recovery markers with athletes dropping 5% of their mass using RWL methods (Artioli et al. 2010, Mendes et al. 2013), but no studies yet to my knowledge have looked at how a 10% weight cut effects performance markers. Plenty of studies are needed in this area to confirm details, but it seems that many of the negative effects of RWL can be avoided with appropriate guidelines.
From the research made, we can conclude that, if we desire to have organic growth in performance is best too:
1) If possible use gradual weight loss (easier to imply if the athlete has to reduce under 5%).
2) Athletes should aim to maximize body fat loss and minimize muscle wasting and dehydration when adjusting weight.
3) An athlete who needs to cut weight then the body fat should not be reduced under 5% for men and 12% for women.
4) During the weight loss period, strength training and BCAA supplementation (basically getting enough quality protein) will help preserve muscle mass
5) During the recovery period after weigh-in, athletes are encouraged to consume high amounts of carbohydrates, fluids and electrolytes. Creatine monohydrate supplementation may also be of use if the athlete will recover for a long period after weighing-in.
And the coach should always take into consideration each athlete separately in how they react to cutting weight.