They may overtax kidneys and reduce muscles’ ability to recover, say studiesTaking ibuprofen and related over-the-counter painkillers could have unintended and
worrisome consequences for people who vigorously exercise. These popular medicines,
known as non-steroidal anti-inflammatory drugs, or NSAIDs, work by suppressing
inflammation. But according to two new studies, in the process they potentially may also
overtax the kidneys during prolonged exercise and reduce muscles’ ability to recover
afterward.
Anyone who spends time around people who exercise knows that painkiller use is common
among them. Some athletes joke about taking “vitamin I,” or ibuprofen, to blunt the pain of
strenuous training and competitions. Others rely on naproxen or other NSAIDs to make hard
exercise more tolerable.
NSAID use is especially widespread among athletes in strenuous endurance sports like
marathon and ultramarathon running.
But in recent years, there have been hints that NSAIDs might not have the effects in athletes
that they anticipate.Some studies have found that those who take the painkillers experience
just as much muscle soreness as those who do not. A few case studies also have suggested
that NSAIDs might contribute to kidney problems in endurance athletes, and it was this
possibility that caught the attention of Dr. Grant S. Lipman, a clinical associate professor of
medicine at Stanford University and the medical director for several ultramarathons.
How they work
NSAIDs work, in part, by blunting the body’s production of a particular group of
biochemicals, called prostaglandins, that otherwise flood the site of injuries in the body.
There, they jump-start processes contributing to pain and inflammation. Prostaglandins also
prompt blood vessels to dilate, or widen, increasing blood flow to the affected area.
Taking NSAIDs results in fewer prostaglandins and consequently less inflammation and less
dilation of blood vessels. Whether these effects are advisable in people exercising for hours
has been uncertain, however.
Study results
So for one of the new studies, published on July 5 in the Emergency Medical Journal, Dr.
Lipman asked 89 participants in several multi-day ultramarathons around the world to
swallow either an ibuprofen pill or a placebo every four hours during a 50-mile stage of their
race.
Afterwards, he and his colleagues drew blood from the racers and checked their levels of
creatinine, a byproduct of the kidneys’ blood filtering process. High levels of creatinine in an
otherwise healthy person are considered to be a sign of acute kidney injury.
The researchers found that many of the ultra runners, about 44%, had creatinine levels high
enough to indicate acute kidney injury after running 50 miles.
But the incidence was particularly high among the runners who had taken ibuprofen. They
were about 18% more likely to have developed an acute kidney injury than the racers
swallowing a placebo. Furthermore, their injuries, based on creatinine levels, tended to be
more severe.
The study did not follow the racers in subsequent days or weeks, but Dr. Lipman believes that
they all recovered normal kidney function soon after the event ended. The experiment also
was not designed to determine why ibuprofen might have increased the risk for kidney
problems in the racers. But Dr. Lipman and his colleagues suspect that, by inhibiting
prostaglandins, the drug prevented blood vessels from widening as they otherwise might
have. Slightly strangling blood flow to the kidneys, he says, might make it harder for those
organs to filter the blood.
The second study, published in May in the Proceedings of the National Academy of Sciences,
raised similar concerns. It found that by reducing the production of prostaglandins, NSAIDs
change how a body responds to exertion, this time deep within the muscles. For that study,
researchers in the department of microbiology at Stanford University looked first at muscle
cells and tissue from mice that had experienced slight muscular injuries, comparable to those
we might develop during strenuous exercise. The tissue soon filled with a particular type of
prostaglandin that turned out to have an important role: It stimulated stem cells within the
muscles to start multiplying, creating new muscle cells that then repaired the tissue damage.
Afterwards, tests showed that the healed muscle tissue was stronger than it had been before.
This microscopic process mimics what should happen when we exercise strenuously,
straining and then rebuilding our muscles.
But when the researchers used NSAIDs to block the production of prostaglandins within the
muscles, they noted that fewer stem cells became active, fewer new cells were produced, and
the muscle tissue, even after healing, was not as strong and springy as in tissues that had not
been exposed to the drug. They saw the same reaction both in isolated muscle cells in petri
dishes and in living mice treated with NSAIDs.
We are not mice, of course. But the findings imply that in people, too, anti-inflammatory
painkillers might slightly impair muscles’ ability to regenerate and strengthen after hard
workouts, says Helen Blau, the director of the Baxter Laboratory for Stem Cell Biology at
Stanford, who oversaw the experiment. “There’s a reason for the inflammation” in the body
after exercise, she says. “It’s part of the regenerative process and not a bad thing.” In fact, at
the cellular level, she says, “it does look as if no pain means no gain.” She suggests that those
of us who exercise might want to consider options others than NSAIDs to relieve the aches
associated with working out and competing.
Dr. Lipman, who is a clinician as well as a distance runner, agrees. “Maybe consider
acetaminophen,” he says, a painkiller found in Tylenol that does not affect inflammation. Or
skip the drugs altogether. “I often tell people, think ice baths,” he says.
Source: The Hindu
worrisome consequences for people who vigorously exercise. These popular medicines,
known as non-steroidal anti-inflammatory drugs, or NSAIDs, work by suppressing
inflammation. But according to two new studies, in the process they potentially may also
overtax the kidneys during prolonged exercise and reduce muscles’ ability to recover
afterward.
Anyone who spends time around people who exercise knows that painkiller use is common
among them. Some athletes joke about taking “vitamin I,” or ibuprofen, to blunt the pain of
strenuous training and competitions. Others rely on naproxen or other NSAIDs to make hard
exercise more tolerable.
NSAID use is especially widespread among athletes in strenuous endurance sports like
marathon and ultramarathon running.
But in recent years, there have been hints that NSAIDs might not have the effects in athletes
that they anticipate.Some studies have found that those who take the painkillers experience
just as much muscle soreness as those who do not. A few case studies also have suggested
that NSAIDs might contribute to kidney problems in endurance athletes, and it was this
possibility that caught the attention of Dr. Grant S. Lipman, a clinical associate professor of
medicine at Stanford University and the medical director for several ultramarathons.
How they work
NSAIDs work, in part, by blunting the body’s production of a particular group of
biochemicals, called prostaglandins, that otherwise flood the site of injuries in the body.
There, they jump-start processes contributing to pain and inflammation. Prostaglandins also
prompt blood vessels to dilate, or widen, increasing blood flow to the affected area.
Taking NSAIDs results in fewer prostaglandins and consequently less inflammation and less
dilation of blood vessels. Whether these effects are advisable in people exercising for hours
has been uncertain, however.
Study results
So for one of the new studies, published on July 5 in the Emergency Medical Journal, Dr.
Lipman asked 89 participants in several multi-day ultramarathons around the world to
swallow either an ibuprofen pill or a placebo every four hours during a 50-mile stage of their
race.
Afterwards, he and his colleagues drew blood from the racers and checked their levels of
creatinine, a byproduct of the kidneys’ blood filtering process. High levels of creatinine in an
otherwise healthy person are considered to be a sign of acute kidney injury.
The researchers found that many of the ultra runners, about 44%, had creatinine levels high
enough to indicate acute kidney injury after running 50 miles.
But the incidence was particularly high among the runners who had taken ibuprofen. They
were about 18% more likely to have developed an acute kidney injury than the racers
swallowing a placebo. Furthermore, their injuries, based on creatinine levels, tended to be
more severe.
The study did not follow the racers in subsequent days or weeks, but Dr. Lipman believes that
they all recovered normal kidney function soon after the event ended. The experiment also
was not designed to determine why ibuprofen might have increased the risk for kidney
problems in the racers. But Dr. Lipman and his colleagues suspect that, by inhibiting
prostaglandins, the drug prevented blood vessels from widening as they otherwise might
have. Slightly strangling blood flow to the kidneys, he says, might make it harder for those
organs to filter the blood.
The second study, published in May in the Proceedings of the National Academy of Sciences,
raised similar concerns. It found that by reducing the production of prostaglandins, NSAIDs
change how a body responds to exertion, this time deep within the muscles. For that study,
researchers in the department of microbiology at Stanford University looked first at muscle
cells and tissue from mice that had experienced slight muscular injuries, comparable to those
we might develop during strenuous exercise. The tissue soon filled with a particular type of
prostaglandin that turned out to have an important role: It stimulated stem cells within the
muscles to start multiplying, creating new muscle cells that then repaired the tissue damage.
Afterwards, tests showed that the healed muscle tissue was stronger than it had been before.
This microscopic process mimics what should happen when we exercise strenuously,
straining and then rebuilding our muscles.
But when the researchers used NSAIDs to block the production of prostaglandins within the
muscles, they noted that fewer stem cells became active, fewer new cells were produced, and
the muscle tissue, even after healing, was not as strong and springy as in tissues that had not
been exposed to the drug. They saw the same reaction both in isolated muscle cells in petri
dishes and in living mice treated with NSAIDs.
We are not mice, of course. But the findings imply that in people, too, anti-inflammatory
painkillers might slightly impair muscles’ ability to regenerate and strengthen after hard
workouts, says Helen Blau, the director of the Baxter Laboratory for Stem Cell Biology at
Stanford, who oversaw the experiment. “There’s a reason for the inflammation” in the body
after exercise, she says. “It’s part of the regenerative process and not a bad thing.” In fact, at
the cellular level, she says, “it does look as if no pain means no gain.” She suggests that those
of us who exercise might want to consider options others than NSAIDs to relieve the aches
associated with working out and competing.
Dr. Lipman, who is a clinician as well as a distance runner, agrees. “Maybe consider
acetaminophen,” he says, a painkiller found in Tylenol that does not affect inflammation. Or
skip the drugs altogether. “I often tell people, think ice baths,” he says.
Source: The Hindu
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