http://www.scientificamerican.com/askexpert/biology/biology64/>
Mark A W Andrews
Muscle cramping is a common problem encountered by athletes and nonathletes
alike. Defined as painful involuntary skeletal muscle contractions, cramps
may be categorized as either nonexercise related or exercise related. The
etiology of the former group may involve hormonal, electrolyte or metabolic
imbalances, or it may result from long-term medication. Diagnostic medical
testing may be required if cramps are a persistent problem. Exercise-related
muscle cramps (ERMC) are much more common. They typically affect the large
muscles of the legs during or immediately after exercise and last for seconds
to a few minutes. These are typically benign but result in intense pain and
may not seem innocuous at the time.
There is little definitive knowledge of the etiology of ERMC. Traditionally,
such cramping was believed to arise from dehydration, electrolyte imbalances
(including magnesium, potassium and sodium), accumulation of lactic acid, or
low cellular energy levels. These proposals, however, have been shown to have
minimal scientific value.
More recent developments indicate that the cause of cramps most likely
involves hyperactivity of the nerve-muscle reflex arc. In this scheme, some
of the normal inhibitory activity of the central nervous system (CNS)
reflexes is lost as a result of CNS fatigue or overuse of feedback
communication with muscles. These spinal reflexes use two receptors, known as
Golgi tendon organs and muscles spindles, found in skeletal muscles. Golgi
tendon organs may become inhibited and muscles spindles can become
hyperactive, leading to sustained activation of the muscle.
It has been suggested that prolonged sitting, poor or abnormal posture or
inefficient biomechanics (all of which may be related to poor flexibility)
predispose these reflexes to malfunctioning. Age also seems to predispose
individuals to cramping--the phenomenon may develop later in life for people
who exercise for years without prior problems. Other factors include
increased body weight and improper footwear. Eccentric muscle contraction and
other musculoskeletal injuries can contribute to the problem.
If a muscle's hyperexcitability is the basis of cramping, then stretching
should attenuate the response. In evidence, it is well recognized that, once
induced, stretching the affected muscle can ameliorate cramping. Stretches
should be held for 15 to 30 seconds or until the muscle relaxes and the cramp
does not recur when the muscle is returned to its normal relaxed position. In
addition, once cramping starts, exercise should be curtailed for at least an
hour, which allows the muscles and the CNS to recover. It is never a good
idea to "run through" these cramps. Applying heat to the area for a few
minutes while stretching may also help the muscle.
Prophylactic stretching of the major muscles of the lower limbs for at least
five to 10 minutes during warm-up and cool-down periods can help prevent
cramps. The importance of flexibility cannot be overstated, particularly for
older athletes. Other recommendations include minimizing running hills and
stairs (limiting eccentric contractions); undergoing a biomechanical
evaluation of your exercise technique; making sure shoes and other equipment
are appropriate and not excessively worn. If, after a few months, cramps do
not respond to these measures, see a qualified sports physician or physical
therapist.
Tuesday, December 8, 2009
Tempo - Tuesday, 8th December 2009
Did a tempo for 25 minutes today, easy warm up for 18 minutes followed by tempo and then cool down for 18 minutes. Built up pace nicely during tempo.
Sunday, December 6, 2009
Aarey Forest - Sunday, 6th December 2009
Did a long run today at Aarey Forest, total time of 92.59 minutes. Ran an inner loop upto the Quality Control laboratory, overall satisfactory, took all the uphill climbs comfortably.
Saturday, December 5, 2009
A Series of Unfortunate Events by Lemony Snicket
Just finished reading the first book of Lemony Snicket's "A Series of Unfortunate Events". The first book is called "The Bad Beginning" involving the unfortunate events surrounding the lives of the Baudelaire children. I think post Harry Potter, children's books have undergone 360 degree change with calamities and disasters being the central theme of any series. Gone are the days of William series books by Richmal Crompton a delightful series involving the danger with which William regularly goes through his life. I guess, the danger part has been upgraded substantially. The first book looked good.
Easy Run - Saturday, 5th December 2009
Did an easy run today of 88.28 minutes, had a good workout followed by some light stretching. First time that Priya was running with me, a decent runner. Wanted to do 90 minutes, satisfied with performance.
Friday, December 4, 2009
The Firm by John Grisham
This is an exciting, throbbing, pulse pounding book "The Firm" by John Grisham. This is one of Grisham's earlier works hence very interesting. Grisham keeps a fast pace throughout, keeping the readers on the edge. It has been made into a movie also starring Tom Cruise, but I feel the book is better than the movie but I believe they have almost true to the story in the movie.
Thursday, December 3, 2009
How to Beat Stress Fractures
http://well.blogs.nytimes.com/2009/12/01/phys-ed-how-to-prevent-stress-fractures/
Phys Ed: How to Prevent Stress Fractures
By GRETCHEN REYNOLDS
MIXA/Getty Images
Stress fractures are one of the more pernicious injuries in sports, afflicting the experienced and the aspiring, with no regard for competitive timing. Last year, Tiger Woods managed to win the U.S. Open despite suffering from stress fractures in his left leg (as well as other leg and knee injuries), while the great British marathoner Paula Radcliffe struggled through the Beijing Olympics Marathon on a leg barely recovered from a stress fracture, one of several she’s suffered. The International Association of Athletics Federations, the world governing body for track and field, recently described stress fractures, with a kind of grim resignation, as “the curse of athletes.”
But studies published in this month’s issue of the journal Medicine & Science in Sports & Exercise offer hope that, at least for runners, simple alterations in their stride or in the strength of their legs might reduce their risk for the most common type of stress fracture.
In one of the studies, undertaken at the University of Minnesota, researchers recruited 39 competitive women runners, ages 18 to 35, and started measuring them. In particular, the scientists wanted to examine the size and shape of their shinbones, or tibias. About half of all stress fractures occur in the tibia, studies show. When you run or jump, that bone is pulled and bent. Sometimes, microscopic fissures form. In most cases, these tiny cracks heal quickly. But, sometimes, continued activity overwhelms the bone’s capacity to recover. The cracks grow and combine into a fracture.
The Minnesota researchers wanted to see whether the shinbones of the runners with a history of stress fractures were weaker than those without. Earlier studies suggested that this would be the case. But few studies have examined the size of the runners’ calf muscles. Bones tend to adapt to the muscles around them; puny muscles can mean puny bones. The Minnesota scientists, using a new machine that examines bone in three dimensions and measuring the runners’ leg muscles, found that, surprisingly, the injured runners’ bones were as strong, in relation to their muscle size as the bones in the uninjured runners. But the injured runners had significantly smaller calf muscles and therefore also slighter bones. The primary difference, the researchers concluded, between the women who suffered stress fractures and those who hadn’t was the size (and presumably strength) of their calf muscles.
This finding should be encouraging to anyone who has had a tibial stress fracture or would prefer not to. “It does seem as if strengthening the calf muscles may be a very easy way” to reduce fracture risk, says Moira Petit, an associate professor of kinesiology at the University of Minnesota and an author of the study. In addition, she said, “our data suggest that you don’t have to strengthen the muscle by much.” A small increase of bulk, achievable by, for instance, rising up on to your toes and sinking back to the floor 10 or 12 times every day, might be enough. Adding even a small amount of calf muscle “serves two purposes,” Ms. Petit says. First, “the strength of the bone will usually increase” in response to the added muscle. And, as a bonus, the new muscle “can absorb more” of the forces generated when you run. So even as the tibia strengthens in response to the new muscle, it also is subjected to less shock. “Really, there’s no downside to this,” Ms. Petit says.
Her results, though, may apply primarily to women; she’s studying male runners, but so far, she says, isn’t seeing the same relationship between their calf-muscle size and bone strength. The other study in the current Medicine & Science in Sports & Exercise, however, did focus on men and their stress fractures, although, in this case, the lead researcher suggests that the findings would be true in women as well. In the work, from Iowa State University in Ames, computer modeling was used to predict what would happen to stress fracture risk if runners changed their strides. The researchers attached reflective markers to the bodies of 10 former or current collegiate-level cross-country runners and had them run repeatedly down a runway nearly 30 meters long, making sure to step onto a force plate that measured how hard they were striking the ground. During successive runs, the men were asked to shorten their natural strides, while maintaining their pace. The scientists entered the data into computer programs that calculated just how much force was being applied to the shinbone under different striding conditions. The researchers determined that reducing stride length by about 10 percent seemed to reduce the stress on the tibia enough to lower the risk of a stress fracture.
Why, though, should shortening your stride affect your tibia at all? “Think of it this way,” says Brent Edwards, lead author of the study and now a post-doctoral research fellow in the Department of Kinesiology and Nutrition at the University of Illinois, in Chicago. “If you spend less time in the flight phase of running” — meaning in the air — “you’ll hit the ground with less force.” On the other hand, you’ll hit the ground more often. But in Mr. Edwards’s models, the reduction in pounding from an abbreviated stride outweighed the shock from a few additional strides per mile.
Even for those of us without a biomechanical expert in the house, gauging a 10 percent reduction in stride is not difficult, Mr. Edwards says. “Ten percent is about as much as you can shorten your stride without it beginning to feel quite uncomfortable,” he says. And absolute precision isn’t necessary. “Seven or eight or nine percent is fine,” he says.
Neither Ms. Petit nor Mr. Edwards suggests, of course, that any, single prevention approach will end all tibial stress fractures. “There are so many elements involved,” Ms. Petit says. Training, hormones, genetics, diet and shoe choice probably all play a role. “But if there’s something easy and benign that you can do to lessen the risk,” she asks, “why not?”
Phys Ed: How to Prevent Stress Fractures
By GRETCHEN REYNOLDS
MIXA/Getty Images
Stress fractures are one of the more pernicious injuries in sports, afflicting the experienced and the aspiring, with no regard for competitive timing. Last year, Tiger Woods managed to win the U.S. Open despite suffering from stress fractures in his left leg (as well as other leg and knee injuries), while the great British marathoner Paula Radcliffe struggled through the Beijing Olympics Marathon on a leg barely recovered from a stress fracture, one of several she’s suffered. The International Association of Athletics Federations, the world governing body for track and field, recently described stress fractures, with a kind of grim resignation, as “the curse of athletes.”
But studies published in this month’s issue of the journal Medicine & Science in Sports & Exercise offer hope that, at least for runners, simple alterations in their stride or in the strength of their legs might reduce their risk for the most common type of stress fracture.
In one of the studies, undertaken at the University of Minnesota, researchers recruited 39 competitive women runners, ages 18 to 35, and started measuring them. In particular, the scientists wanted to examine the size and shape of their shinbones, or tibias. About half of all stress fractures occur in the tibia, studies show. When you run or jump, that bone is pulled and bent. Sometimes, microscopic fissures form. In most cases, these tiny cracks heal quickly. But, sometimes, continued activity overwhelms the bone’s capacity to recover. The cracks grow and combine into a fracture.
The Minnesota researchers wanted to see whether the shinbones of the runners with a history of stress fractures were weaker than those without. Earlier studies suggested that this would be the case. But few studies have examined the size of the runners’ calf muscles. Bones tend to adapt to the muscles around them; puny muscles can mean puny bones. The Minnesota scientists, using a new machine that examines bone in three dimensions and measuring the runners’ leg muscles, found that, surprisingly, the injured runners’ bones were as strong, in relation to their muscle size as the bones in the uninjured runners. But the injured runners had significantly smaller calf muscles and therefore also slighter bones. The primary difference, the researchers concluded, between the women who suffered stress fractures and those who hadn’t was the size (and presumably strength) of their calf muscles.
This finding should be encouraging to anyone who has had a tibial stress fracture or would prefer not to. “It does seem as if strengthening the calf muscles may be a very easy way” to reduce fracture risk, says Moira Petit, an associate professor of kinesiology at the University of Minnesota and an author of the study. In addition, she said, “our data suggest that you don’t have to strengthen the muscle by much.” A small increase of bulk, achievable by, for instance, rising up on to your toes and sinking back to the floor 10 or 12 times every day, might be enough. Adding even a small amount of calf muscle “serves two purposes,” Ms. Petit says. First, “the strength of the bone will usually increase” in response to the added muscle. And, as a bonus, the new muscle “can absorb more” of the forces generated when you run. So even as the tibia strengthens in response to the new muscle, it also is subjected to less shock. “Really, there’s no downside to this,” Ms. Petit says.
Her results, though, may apply primarily to women; she’s studying male runners, but so far, she says, isn’t seeing the same relationship between their calf-muscle size and bone strength. The other study in the current Medicine & Science in Sports & Exercise, however, did focus on men and their stress fractures, although, in this case, the lead researcher suggests that the findings would be true in women as well. In the work, from Iowa State University in Ames, computer modeling was used to predict what would happen to stress fracture risk if runners changed their strides. The researchers attached reflective markers to the bodies of 10 former or current collegiate-level cross-country runners and had them run repeatedly down a runway nearly 30 meters long, making sure to step onto a force plate that measured how hard they were striking the ground. During successive runs, the men were asked to shorten their natural strides, while maintaining their pace. The scientists entered the data into computer programs that calculated just how much force was being applied to the shinbone under different striding conditions. The researchers determined that reducing stride length by about 10 percent seemed to reduce the stress on the tibia enough to lower the risk of a stress fracture.
Why, though, should shortening your stride affect your tibia at all? “Think of it this way,” says Brent Edwards, lead author of the study and now a post-doctoral research fellow in the Department of Kinesiology and Nutrition at the University of Illinois, in Chicago. “If you spend less time in the flight phase of running” — meaning in the air — “you’ll hit the ground with less force.” On the other hand, you’ll hit the ground more often. But in Mr. Edwards’s models, the reduction in pounding from an abbreviated stride outweighed the shock from a few additional strides per mile.
Even for those of us without a biomechanical expert in the house, gauging a 10 percent reduction in stride is not difficult, Mr. Edwards says. “Ten percent is about as much as you can shorten your stride without it beginning to feel quite uncomfortable,” he says. And absolute precision isn’t necessary. “Seven or eight or nine percent is fine,” he says.
Neither Ms. Petit nor Mr. Edwards suggests, of course, that any, single prevention approach will end all tibial stress fractures. “There are so many elements involved,” Ms. Petit says. Training, hormones, genetics, diet and shoe choice probably all play a role. “But if there’s something easy and benign that you can do to lessen the risk,” she asks, “why not?”
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Zodiac
American true crime mystery movie “Zodiac” (2007) directed by David Fincher and starring Jake Gyllenhaal, Mark Ruffalo, Robert Downey Jr. ...
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