Why pain killers can stop muscle growth


New member
some info i found on pain killers

Why pain killers can stop muscle growth
Over-the-counter pain killers (such as ibuprofen) are a popular way to ease the
pain and soreness that manifests itself 24-48 hours after a tough workout.

However, what most people don't realize is that high doses of these pain killers
can "blunt" the normal rise in protein synthesis that occurs after exercise. In
other words, while they can control the pain, regular use of these pain killers
could put the brakes on muscle growth.

Pain killers
Protein synthesis is one important factor controlling the rate of muscle growth.
In simple terms, your muscles grow larger when protein synthesis is greater than
protein breakdown.

Think of your muscles like a bath. Water coming into the bath is known as
protein synthesis. Water leaving the bath is known as protein breakdown. When
there's more water coming into the bath than there is going out, you'll end up
with bigger muscles.

One of the ways that pain killers such as ibuprofen work is to suppress the
synthesis of substances known as prostaglandins. However, these very same
prostaglandins also have a profound effect on muscle growth.

Some evidence linking prostaglandins to a reduced rate of protein synthesis
comes from a trial published in the Journal of Clinical Endocrinology and

A group of male subjects with an average age of 25 were assigned to one of three
groups. All groups performed 10-14 sets of 10 eccentric repetitions for the
muscles on the front of the thigh.

* After completing the workout, group one received the maximal over-the-counter
dose of ibuprofen (1200 milligrams daily).

* Group two was given acetaminophen (4000 milligrams daily).

* The third group received a placebo (a "dummy" supplement) that contained no
active ingredients.

When muscle samples were analyzed 24 hours after exercise, levels of a
prostaglandin called PGF2 increased by an average of 77% in the group using the
placebo. This represents the normal response to exercise. However, PGF2 levels
dropped by 1% and 14% in the ibuprofen and acetaminophen groups respectively.

Of course, this was only a short-term study. The extent to which the prolonged
use of pain killers affects muscle growth over a period of several weeks or
months is open to debate.

However, while the occasional use of pain killers isn't likely to cause a
problem, they're certainly not something you should use too often.

If you do want to avoid feeling sore after exercise, the best way is simply to
ease your way into a new training program gradually.

[Source: thefactsaboutfitness.com]
Very interesting info adida. I've been taking painkillers (ibuprofen and diclofenac) for almost 2 months due to my shoulder tendonitis and I think I almost stopped gaining muscle. Fortunately tomorrow is my last day.