In the last few years, non-steroidal anti-inflammatory drugs (NSAIDs) and acetaminophen have received a ‘black eye’ for their detrimental effect on muscle hypertrophy. Many studies have reported that the maximum dose of NSAIDs can inhibit muscle hypertrophy, while a minimum dose may not have the same detrimental effect. NSAIDS topped a recent poll of the most commonly-abused over-the-counter drugs for pain among athletes. Whether NSAIDs will inhibit muscle hypertrophy remains to be determined, as more research needs to be conducted, but one must also take into consideration the long-term effect that NSAIDs have on kidney health.

A new study was published in a peer-reviewed scientific journal that may give weightlifters an alternative to using NSAIDs. In September’s Medicine and Science in Sports and Exercise, a new protease supplement was found to enhance muscle recovery after strenuous weightlifting. Proteases are by definition, enzymes that break down proteins. Proteases are involved in numerous physiological processes, such as digestion of food to highly-regulated bodily procedures such as blood clotting and immune function. Two previous studies found that the use of a protease supplement was able to reduce muscle soreness and enhance muscle recovery after a damaging bout of eccentric exercise. However, their exact role in reducing muscle soreness remains largely a mystery.

NSAIDs work by reducing muscle inflammation. Generally, after intense exercise, damage occurs to muscle tissue and there is an increase in inflammatory mediators such as leukocytes, macrophages, etc. The inflammatory response seems to be a necessary component of the muscle hypertrophy response.

Researchers from the University of Waco in the Exercise and Biochemistry Laboratory decided to revisit this concept, and study the role of protease supplementation and muscle recovery more closely. They had young men consume a protease supplement (44.7 grams of papain, 99.9 milligrams of bromelain, 5.593 grams of fungal enzymes with endopeptidase/exopeptidase activity, and 86.4 milligrams of calcium citrate) for 21 days. After that, they performed a grueling exercise bout of downhill running for 45 minutes, which is one of the most damaging forms of exercise one can perform. Subjects received either a protease supplement or a placebo during this time.

The results of protease supplementation were quite impressive. In the days after a bout of damaging exercise, the protease supplement was able to improve muscle function.

It has been suggested that protease supplementation can enhance muscle recovery via interaction with the immune system. In the placebo group, significantly higher levels of interleukin-6 and interleukin-12 were observed. But the protease group had blunted levels of the pro-inflammatory mediators IL-6 and IL-12.

Another interesting finding was that the protease group had blunted levels of COX-2 enzyme expression. Celebrex is a commonly-used COX-2 inhibitor for the relief of arthritis. The researchers speculated that the protease supplement, through inhibition of the inflammatory response, might enhance muscle recovery.

It seems there was an alteration in circulating inflammatory response, as noted by the reduced macrophage response to the damaged muscle. Blunted IL-6 and COX-2 expression were also observed after protease supplementation. As for inflammation and muscle hypertrophy, remember this is an intricate process. Too much inflammation can inhibit muscle growth, just as too little can be just as detrimental— so don't be overly concerned about the reductions in COX-2 and interleukin-6 production. Thus, protease supplementation may be a new way to enhance muscle recovery without the damaging effects of NSAIDs.



Reference:

Buford TW, Cooke MB, Redd LL, Hudson GM, Shelmadine BD, Willoughby DS. Protease Supplementation Improves Muscle Function after Eccentric Exercise. Med Sci Sports Exerc, 2009 Sep 2.