A new study by researchers at the Human Performance Laboratory, Ball State University, has found that taking ibuprofen or acetaminophen in long-term resistance training boosts muscle mass/strength.
In the study, researchers found that taking daily-recommended dosages of ibuprofen and acetaminophen caused a substantially greater increase over placebo in the amount of quadriceps muscle mass and muscle strength gained during three months of regular weight lifting.
Dr. Chad Carroll, a postdoctoral fellow working with Dr. Todd Trappe, and colleagues randomly assigned 36 men and women, between 60 and 78 years of age to daily dosages of either ibuprofen, acetaminophen, or a placebo.
The participants and the researchers did not know who was receiving which treatment until the end of the study.
The study included three months of weight training, 15-20 minute sessions conducted in the Human Performance Laboratory three times per week.
The researchers were aware that training at this intensity and for this time period would significantly increase muscle mass and strength.
And they expected the placebo group to show such increases, as its members did. However, they were surprised to find that the groups using either ibuprofen or acetaminophen did even better.
A previous study from the same researchers, measuring muscle metabolism had looked at changes over a short period of 24 hour.
The study found that both ibuprofen and acetaminophen had a negative impact, by blocking a specific enzyme cyclooxygenase, commonly referred to as COX.
However, Dr. Trappe Over said that over three months, the chronic consumption of ibuprofen or acetaminophen during resistance training appears to have induced intramuscular changes that enhance the metabolic response to resistance exercise, allowing the body to add substantially more new protein to muscle.
Now, the researchers are conducting assays of muscle biopsies taken before and after the three-month period of resistance training, in order to understand the metabolic mechanism of the positive effects of ibuprofen and acetaminophen.
The study was presented at Experimental Biology 2008 in San Diego on April 6.