This is a fear that stops many would-be runners in their tracks and lurks in the back of the mind of even the most experienced runners. Running and injuries go together like shin splints and ice, so it's entirely reasonable to wonder about the prospects of long-term damage.
These fears should be put to rest by a pair of long-term studies due to be published this year.
In next month's Skeletal Radiology, a team of Austrian radiologists presents knee MRIs of seven runners who had taken part in a previous MRI study before running the Vienna marathon in 1997. The use of MRIs offers a significant diagnostic advantage compared to earlier studies that relied on X-rays.
The results were clear: no new damage in the knee joints of the six subjects who had continued running in the intervening decade. "In contrast, the only person who had given up long-distance running showed severe deterioration in the intra-articular structures of his knee," the authors note.
An even more long-term study at Stanford University has been following 45 runners and 53 non-runners since 1984. All had been taking regular X-rays. The latest results, which will appear in a future edition of the American Journal of Preventive Medicine, show that after 18 years, 20 per cent of the runners had developed osteoarthritis in the knee, compared with 32 per cent of non-runners.
These studies raise a possibility that several earlier studies have proposed: Running may help preserve the joints. But that's not a conclusion that can be drawn at this point, says Eliza Chakravarty, lead author of the Stanford study.
"I don't think I would strongly recommend running for the purpose of protecting the knees."
One drawback with both studies is selection bias. The runners in both cases were committed recreational runners who had a history of being able to run without serious problems.
Data for non-runners who are considering taking up running are harder to come by - a gap that was partly addressed by a large-scale study that appeared last year in the journal Arthritis & Rheumatism, involving 1,279 subjects from the famously long-running Framingham Heart Study.
Rather than studying "runners" versus "non-runners" the researchers examined the general study population, looking for associations between exercise (including running) and the development of knee osteoarthritis over a nine-year period. They found no link, suggesting even overweight non-runners can start exercising without putting their knees at risk.
In sharp contrast, though, the American College of Sports Medicine recently reported that each additional pound of body mass puts four extra pounds of stress on the knee, so packing on a pound a year for about a decade increases your chances of developing arthritis by 50 per cent - a fairly powerful argument for running to keep off weight and protect your knees.
Of course, the decision doesn't have to be strictly utilitarian. As one of the Vienna study participants (who was preparing to run his 37th marathon) put it in a recent e-mail to lead author Wolfgang Krampla, "Even if minor aches and pains occur over the years, the gain in joie de vivre far outweighs them."
Alex Hutchinson is a former member of Canada's long-distance running team, and has a PhD in physics.
Source: GlobeandMail.caDrug maker Merck & Co. said Wednesday that the U.S. Food and Drug Administration has rejected expanding the use of the cervical cancer vaccine Gardasil to include women ages 27 to 45.
The federal agency cited "issues that preclude approval" within the expected time frame for a review, Merck said.
Gardasil was approved in 2006 for girls and women between nine and 26 years old to prevent cervical cancer caused by the human papillomavirus, or HPV. The agency's current action does not affect this population's use.
The FDA decision bars Merck from marketing Gardasil to women ages 27-45, but does not prevent those women from getting the vaccine from their doctors.
Merck said that the agency identified several issues related to the application in a "complete response" letter, including stating that the data submitted does not support extending Gardasil's use to include non-vaccine HPV types.
Merck also reaffirmed its goal of attaining compound annual growth in its businesses of between four per cent and six per cent from 2005 through 2010.
Gardasil is the only cervical cancer vaccine approved for the lucrative U.S. market. It is outselling another vaccine, Cervarix, from GlaxoSmithKline PLC, in worldwide sales, analysts said, garnering over $1 billion in sales since its June 2006 U.S. launch.
"This is clearly not what Merck wanted. It reflects the painstakingly slow process that the FDA has in approving anything," WBB Securities analyst Steve Brozak said. "I think this is one where they would rather err on the side of getting another 23 pounds of documents."
New Jersey-based Merck said it has already had discussions with the FDA and plans to respond next month.
In afternoon trading Wednesday, its stock was down eight cents, or 0.2 per cent, to $36.95 US in New York.
Gardasil is approved in Canada for use in women aged nine to 26.
Source: CBC.caHealth Canada has issued a warning about adverse neuropsychiatric effects linked to Champix, a drug intended to help smokers butt out for good.
A number of patients taking Champix (varenicline tartrate) have experienced unusual feelings of agitation, depressed mood, hostility, changes in behaviour or impulsive or disturbing thoughts, such as ideas of self-harm or of harming others, Health Canada said Friday in an advisory.
The medication acts on sites in the brain affected by nicotine. The drug helps ease withdrawal symptoms and blocks the effects of nicotine if users resume smoking.
Champix, made by Pfizer Inc. and sold under the brand name Chantix in the United States, has been sold in Canada since April 2007. In the year following its approval, 226 Canadian cases of neuropsychiatric adverse events have been reported. In that period, more than 708,500 prescriptions for the drug have been filled across the country.
Health Canada issued the following guidelines to the public:
"Quitting smoking can also be associated with changes in mood and behaviour, with or without taking medication to help quit," said the federal department in its advisory. "A doctor or pharmacist should be consulted should these symptoms or those described above be experienced, since guidance has been provided to health-care professionals on how to use Champix in patients, including those patients who may also have mental health problems."
Health Canada, which published an article concerning Champix in the Canadian Adverse Reaction Newsletter in April, said any case of serious change in mood or behaviour or other serious or unexpected adverse reactions in patients receiving Champix should be reported.
Source:CBC.ca
The province already bans smoking in workplaces and public areas, such as bars and restaurants. The new ban will also protect kids under the age of 16 who are being exposed to dangerous levels of second-hand smoke, said Health Promotion Minister Margarett Best.
"This is about protection of our most vulnerable citizens — children who do not have a voice," Best told the legislature.
Premier Dalton McGuinty once dismissed a province-wide ban as a slippery slope that infringed too much on people's rights, but changed his tune in March and threw his government's support behind the private members' bill.
Offenders will also face much lighter fines than originally envisioned by Liberal backbencher David Orazietti, who championed the ban. Drivers and passengers who don't butt out in vehicles carrying children won't be fined more than $250 for each offence, rather than being penalized up to $1,000.
Nova Scotia and British Columbia have already outlawed the practice, which critics liken to child abuse. Prince Edward Island and New Brunswick are also considering a similar ban.
Police will be expected to enforce the law once it takes effect, but the province is counting on most people abiding by the law, said Best.
Ontario Provincial Police have said the ban won't make their job more onerous, as they are already inspecting for seatbelts and child car seats.
The province says kids are exposed to up to 27 times the toxins when they're in enclosed spaces like a car, which can worsen asthma and lead to other respiratory illnesses.
Mychoice.ca, a smokers' rights group financed in part by the tobacco industry, has raised concerns that the ban will eventually extend to private homes, but Mr. McGuinty said that's not under considerationCan I get fit by exercising just a few minutes a week?
The answer
Breathless claims about exercise regimens that produce near-instant results with minimal effort are generally the domain of late-night infomercials and their ilk.
So it may seem surprising that one of the hot topics at last month's American College of Sports Medicine annual meeting in Indianapolis was research on "high-intensity interval training" (HIT), suggesting that many of the benefits of traditional endurance training can be achieved with a few short bouts of intense exercise totalling as little as seven minutes a week.
The latest research on the topic, from a group at
The McMaster group has produced a series of remarkable studies on HIT over the past few years, led by exercise physiologist Martin Gibala.
Their subjects cycled as hard as they could for 30 seconds, then rested for four minutes, and repeated four to six times. They did this short workout three times a week.
"The gains are quite substantial," Dr. Gibala says. When compared with control subjects who cycled continuously for up to an hour a day, five times a week, the HIT subjects showed similar gains in exercise capacity, muscle metabolism and cardiovascular fitness.
Similar studies by
The results are no surprise to elite cyclists, runners and swimmers, who have relied on interval training for decades to achieve peak performance. To break the four-minute mile in 1954, Roger Bannister famously relied on interval sessions of 10 60-second sprints separated by two minutes of rest, because his duties as a medical student on clinical rotation limited his training time to half an hour a day at lunch.
Such time constraints are the main reason Dr. Gibala advocates HIT, since studies consistently find that lack of time is the top reason that people don't manage to get the 30 to 60 minutes of daily exercise recommended by public health guidelines.
"We're not saying that it's a panacea that has all the benefits of [traditional] endurance training," he says. "But it's a way that people can get away with less."
High-intensity exercise is generally thought to carry some risks, so sedentary or older people should check with a doctor before trying HIT. Interestingly, though,
There is a catch - the disclaimer at the end of the infomercial, if you will. To cram the benefits of an hour-long workout into a few short minutes, you also have to compress the effort you would have spent.
"That's the trade-off," Dr. Gibala says. "Going all out is uncomfortable. It hurts." But at least with this approach it's over quickly.
How to take a HIT
The guiding principle of HIT is that the shorter the workout, the higher the intensity you need to reap the benefits. "Basically,"
The Street-lighter: For a sedentary person who gets winded walking around the block, HIT can be as simple as walking more quickly than usual between two light poles. Then back off, and repeat after you have recovered.
The Bannister: Go hard for one minute, then recover (either
by slowing down or stopping completely) for one to two minutes. Repeat 10 times. This is a staple workout for a wide range of abilities, suitable for any
cardio activity.
The Timesaver: Dr. Gibala's protocol of 30 seconds of all-out cycling four to six times with four minutes rest is the shortest workout shown to be effective. But achieving the necessary intensity outside the lab is extremely challenging, so it's best suited to experts and those capable of extreme self-punishment.
All these workouts should be preceded by a gentle warm-up of at least five to 10 minutes.
Alex Hutchinson
There are some tantalizing clues that physical activity might spur changes in the brain to do just that. Now the U.S. government is beginning a push for hard research to prove it.
This is not about getting average people to achieve the so-called runner's high, a feat of pretty intense athletics.
Instead, the question is just how regular physical activity of varying intensity - dancing, bicycling, swimming, tae kwan do - might affect mood, academic performance, even the very reward systems in the brain that can get hijacked by substance abuse.
What first caught the attention of National Institute on Drug Abuse chief Dr. Nora Volkow: A study found tweens and teens who reported exercising daily were half as likely to smoke as their sedentary counterparts, and 40 per cent less likely to experiment with marijuana.
Volkow knows - from her own almost 10-kilometre daily runs and from her scientific experiments - that the brain literally likes physical activity. Exercise seems to invigorate neurochemicals that sense and reinforce pleasure"In children, it's innate," she notes. "Children want to move."
But the nation's children are becoming more sedentary, as illustrated by the obesity epidemic, "screen time" replacing outdoor play and a drop in school phys-ed. And as youngsters approach adolescence, the run around the yard that used to be fun too often becomes a chore - the dreaded jog around the school track or the nagging to get off the couch. The sedentary teen turns into the sedentary adult.
"Why do we lose the ability to experience pleasure from physical activity?" asks Volkow.
Last week she brought more than 100 specialists in exercise and neurobiology to a two-day conference to explore physical activity's potential in fighting substance abuse, and announced $4 million in new research grants to help.
Drug treatment programs often include exercise, partly to keep people distracted from their cravings, but there's been little formal research on the effects.
The best evidence: Brown University took smokers to the gym three times a week and found adding the exercise to a smoking-cessation program doubled women's chances of successfully kicking the habit. The quitters who worked out got an extra benefit: They gained half as much weight as women who managed to quit without exercising, says lead researcher Dr. Bess Marcus.
She now is working with the YMCA on a larger, NIDA-funded study to prove the benefit.
Marcus cautions that people trying to kick an addiction have a powerful incentive to exercise. Could that possibly translate into prevention? Among the clues:
-Rats were less likely to ingest amphetamines if their cages had running wheels, suggesting exercise stimulated a reward pathway in the brain to leave them less vulnerable to the drug's rush.
-In people, exercise acts as a mild antidepressant and relieves stress. Depression, anxiety and stress increase risk of alcoholism, smoking or drug abuse.
-Volkow is intrigued that attention deficit disorder and obesity both involve problems with the brain chemical dopamine, one system that drugs hijack to create addiction.
-Baby monkeys who don't play enough in childhood have problems controlling aggression when they're older. The most aggressive tend to have defects involving the feel-good brain chemical serotonin - and binge-drink when researchers offer them alcohol.
-Back to rats, physical activity increases production of growth factors and stem cells in key brain regions important for learning and mood; increases formation of blood vessels; and strengthens communication networks between brain cells.
Together, that's far too little research to know if exercise really matters for substance abuse, scientists at the National Institutes of Health meeting cautioned.
But, a few studies of school-age children suggest physical activity predicts better performance on math, verbal and other tests - and better school performance in turn is linked to lower risk for substance abuse.
And getting sedentary seniors moving improves brain function - research aimed at preventing dementia, not drug abuse, although the improvement is in an area that in younger people is linked to risky decision-making.
A caveat: If your own youth includes memories of parties with beer-guzzling athletes, well, the research concurs. A major study that tracks adolescent risk behaviours found that by 12th grade, exercise offers no protection against binge-drinking.
"Now the kids who exercise the most actually drink the most," says Dr. Lloyd Johnston of the University of Michigan. It may have to do with the celebratory nature of team sports, or getting revved for college - or, other researchers suggested, even that competition is to blame.
Mercury in dental amalgams may pose health risks to children, fetuses and pregnant women, the U.S. Food and Drug Administration is warning.
The FDA issued a statement, on its website Wednesday, about the potential dangers of dental amalgams.
As part of a legal settlement reached Monday, the federal agency has agreed to release a new ruling on the safety of dental amalgams in July 2009, and alert consumers about potential related hazards. Consumer advocacy groups, including Moms Against Mercury, called for a ban on the fillings in the U.S.
"Dental amalgams contain mercury, which may have neurotoxic effects on the nervous systems of developing children and fetuses," the FDA said.
"When amalgam fillings are placed in teeth or removed from teeth, they release mercury vapour. Mercury vapour is also released during chewing."
The FDA says consumers should not have amalgam fillings removed.
Health Canada says that while amalgam has been shown to release mercury in the body, the levels are not serious enough to cause adverse health effects.
The federal agency says current data does not support hypotheses linking mercury exposure with Alzheimer's disease, amyotrophic lateral sclerosis, multiple sclerosis and Parkinson's disease.
But the federal agency notes patients with kidney disease and pregnant women should avoid dental amalgams given that mercury has been shown to cross the placental barrier and weaken kidney function at sub-clinical levels of exposure.
Sweden and Norway have banned the use of dental amalgams, citing health concerns.
The affected produce was distributed in cartons of six or nine cantaloupes and bears stickers with the following information:
KingFisher Brand
Produce of U.S.A.
UPC 0 33383 11600 6
4050
Fisher Ranch Corp., Blythe, CA, 92225
These cantaloupes were distributed in Ontario and sold between May 16 and June 2.There have been no reported illnesses associated with the consumption of the affected cantaloupes.
Consumption of food contaminated with this bacteria may cause salmonellosis.
In young children, the elderly and people with weakened immune systems, salmonellosis may cause serious and sometimes deadly infections.
In otherwise healthy people, salmonellosis may cause short-term symptoms such as high fever, severe headache, vomiting, nausea, abdominal pain and diarrhea.
The importer, Gambles Ontario Produce Inc. of Toronto, is voluntarily recalling the affected cantaloupes from the marketplace.
The CFIA is monitoring the effectiveness of the recall.
Source: Canadian Press
A consumer advocacy group called on the Food and Drug Administration Tuesday to ban the use of eight artificial colourings in food because the additives may cause hyperactivity and behaviour problems in some children.
Controlled studies conducted over three decades have shown that children's behaviour can be worsened by some artificial dyes, says the Center for Science in the Public Interest. The group noted the British government is successfully pressuring food manufacturers to switch to safer colourings.
Over the years, the FDA has consistently disputed the centre's assertion. The agency's website contains a 2004 brochure that asks the question: "Do additives cause childhood hyperactivity?"
"No. Although this hypothesis was popularized in the 1970s, well-controlled studies conducted since then have produced no evidence that food additives cause hyperactivity or learning disabilities in children," the agency said.
Julie Zawisza, an FDA spokeswoman, said Tuesday that color additives undergo safety reviews before approval for marketing and that samples of each artificial colouring are tested. She said the agency reviewed one of the studies the centre cites in calling for a ban.
"[We] didn't find a reason to change our conclusions that the ingredients are safe for the general population," Zawisza said. "Also note that the European Food Safety Agency has a similar view as FDA's."
Dyes are used in countless foods and sometimes used to simulate the colour of fruits or vegetables. The additives are particularly prevalent in the cereals, candies, sodas and snack foods pitched to kids.
"The purpose of these chemicals is often to mask the absence of real food, to increase the appeal of a low-nutrition product to children, or both," said Michael F. Jacobson, the centre's executive director.
"Who can tell the parents of kids with behavioural problems that this is truly worth the risk?"
The centre's petition asks the FDA to require a warning label on foods with artificial dyes while it mulls the group's request to ban the dyes outright.
The colourings the centre seeks to ban are:
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