Adding to this site’s archived safety studies and legal reforms addressing Rapid Extreme Weight Cut practices in MMA and other combat sports, a recent Master’s Thesis paper was published by Oliver Roland Barley at the School of Medical and Health Science EDITH COWAN UNIVERSITY, looking at the effects of Rapid Extreme Weight Cuts in MMA Athletes.
The study, titled “The effects of acute dehydration of 5% body mass on performance and physiology of mixed martial arts athletes” recruited 14 MMA athletes with at least 2 years of competitive experience. These athletes were broken down into a control group and a group who underwent a rapid extreme weight cut via dehydration where 5% of their bodyweight was lost.
After 3 hours of rehydration both groups underwent a series of performance tests, including vertical jump, medicine ball throw, wrist grip and repeated sled push. These were repeated a further 21 hours later after greater rehydration.
Not surprisingly the dehydrated group had compromised performance with the author noting the following results –
As expected, the dehydration observed in this study was associated with a decline in anaerobic and aerobic performance. Indeed, the specific repeat sled push protocol in this study was developed to stress both aerobic and anaerobic metabolism. The present study observed a 19% reduction in average speed over the repeated sled push test alongside a 5% reduction in peak speed. A 6% reduction in average speed of the first five sprints during the repeat sled push test was observed when comparing at 3 h post between conditions. The decrements in repeat sled push test performance were still being observed 24 h post DHY protocol with a 10% reduction in average speed, a 5% reduction in peak sprint time and a 6% reduction in average speed of the first five sprints. Further to these performance changes in the repeat sled push test, an increase in total test time at both 3 h and 24 h post DHY compared with the CONT was observed alongside a significantly larger fatigue index 3 h post DHY protocol. Furthermore, due to exhaustion less athletes were able to complete the repeat sled push test 3 h post DHY
These poor results led the author to conclude that”The observations of this present study indicate that current weight loss practices in MMA and other combat sports may not be conducive to the best physical performance possible. Current practices should be reconsidered since performance was compromised even following 24 h of recovery. Future research should investigate possible physiological mechanisms behind the observed decrement in performance.”
Combat Sports Law 