Alex is the perfect guy to do this exercise myth-busting as he is a competitive runner, professional journalist, and has a Ph.D. in physics. His writing is crisp, uncluttered, and bears the understated humor of a Canadian. To be honest, I enjoyed his book so much that I was contemplating blogging about most of his conclusions. However, I don’t want to teeter on the edge of copyright infringement, so I’ll just provide you with some highlights from my favorite sections of the book:
1. Do compression garments help you exercise? I’ve wondered this many times as I jiggled my way down the road on a long run. I’ve always liked the theory behind tight outer-garments, that they reduce unnecessary movement during running, thus making one’s movement more efficient and reducing the bounce and drag on muscles and skin. They may also help with blood return to the heart and reduction in peripheral edema, speeding recovery from exercise. Believing the plausibility of the argument, I have indeed sprung for some rather expensive running tights.
So what does the scientific literature have to say about compression garments’ role in exercise? Apparently there is nothing conclusive yet. Small studies have shown no clear improvement in exercise economy, athletic power or endurance, or recovery from exercise. The only measurable benefits appear to have occurred in those who believed that the compression garments would help their performance. A nice reminder of the importance of the “mind-body” connection in athletic pursuits. Bottom line: if you like how you feel in compression garments, by all means wear them. But don’t expect any dramatic improvements in anything more than your jiggle factor.
2. Will sitting too long at work counteract all my fitness gains? The short answer to this question is: possibly. I was surprised to note that at least one large study found that sitting for more than six hours per day increased one’s risk of death by 18-37% regardless of how much exercise one performed in the other eighteen hours of the day. Long periods of sitting appear to be quite bad for your health, so getting up and moving around every hour or more is important if you have a sedentary job or lifestyle.
3. Does listening to music or watching TV help or hurt my workout? Listening to faster-tempo music can result in increased exercise effort (in many cases completely unconsciously), while TV-watching usually results in a reduced exercise effort. This is because watching videos requires visual attention and subtle changes in balance and movement occur to accomplish it.
4. Will stretching help me avoid injuries? As a person with limited flexibility, I found this section of the book to be quite comforting. As I have blogged previously, stretching has not been shown to reduce the risk of injury or post-exercise soreness. In fact, it can decrease power and speed for certain athletes, though it is important for those who intend to perform great feats of flexibility (such as gymnastics).
5. Should I take pain killers for post-workout soreness? Interestingly, non-steroidal anti-inflammatory drugs (NSAIDs) are not particularly effective in reducing post-exercise pain and can even interfere with muscle repair. NSAIDs block prostaglandins, which are important in collagen synthesis. While NSAIDs are useful in reducing inflammation and swelling in acute injuries (such as an ankle sprain), general muscle soreness isn’t a good reason to pop some ibuprofen.
6. Will drinking coffee help or hinder my performance? I’m one of the few people I know who doesn’t drink coffee, so I was surprised to discover that I may have been missing out on an important exercise enhancer. According to decades of research, caffeine is likely to improve your exercise performance. Studies have shown that pure caffeine (not necessarily in its coffee form) enhances sprint performance as well as endurance activities up to two hours. In 2004 the World Anti-Doping Agency removed caffeine from its list of restricted substances, so expect to see some caffeinated athletes in this summer’s Olympics.
7. What’s the best way to breathe during exercise? If you’ve ever marveled at your own panting, you’ve also probably wondered if there is a more efficient way to breathe – or at least a less embarrassing way. The answer is no. Studies have shown that people who consciously work to make their breathing less labored expend more energy and get less oxygen in the process. So, keep on breathing the way your body wants to… you’re naturally more efficient at it than you think.
I hope that these little tidbits have whet your appetite for more of Alex’s excellent insights. I have fully equipped myself with fast-paced music and a little caffeine, as I move my inflexible, jiggly, panting self down the road on another long run.
If you’re like me, you probably feel guilty about not making stretching a part of your regular exercise routine. I attributed my history of low back pain to lack of stretching, although when I began practicing yoga last year I experienced no lasting benefits. Stretching was uncomfortable and I saw very little improvement in my flexibility for all my efforts. I eventually gave up after one well-meaning yogi told me that I may just be “genetically incapable” of making much progress. I turned to strength training and running with complete resolution of my back pain – though with a continued inability to bend over and touch my toes or sit cross legged for prolonged periods. Oh well. No traditional Japanese dining for me!
And so it was with great surprise that I read the conclusions from a recent analysis (by Alex Hutchinson, Ph.D.) of the science of stretching. I recommend that you read it for yourself (along with the links to the primary source literature). But I’m going to summarize his findings here:
Q: Does stretching reduce the risk of injuries during exercise?
A: Not that we can prove.
Q: Does stretching help you avoid soreness after exercise?
Q: Does stretching make you stronger or faster?
A: No. In fact, there is some evidence that stretching can have the opposite effect. Why? Muscles have spring-like properties, so that when they are stretched out, they become less able to transmit as much force. Imagine the difference between the power of a thick, metal spring and a thin metal spring. Studies have shown that the more flexible you are, the less efficient you are as a runner.
My take away message is that there’s no need to flagellate yourself into stretching if you don’t like it. It really depends on what you need to do with your body – if you’re a gymnast, then stretching will always be a part of your life. If you’re a runner who hates yoga, so be it. You may never win a toe-touching competition, but then again, you can probably crush the Primal Games competition. Wish me luck as I attempt to do just that in two weeks!
Carpal Tunnel Syndrome (CTS) is common and is the result of the median nerve becoming squeezed or “entrapped” as it passes through the wrist down into the palm of the hand. Because this is a sensory nerve, the compression causes tingling, burning and itching numbness in the palm of the hand and fingers. A different nerve goes to the little finger and the lateral half of the 4th finger so the sensation there would feel normal. There is often a sensation of swelling even though there is rarely any true edema that can be seen in CTS.
The symptoms of Carpal Tunnel Syndrome usually start at night when people sleep with flexed wrists. As it progresses, the tingling and numbness can be felt on and off during the day. It can cause decreased grip strength and weakness in the hands.
CTS can be worsened by medical conditions like rheumatoid arthritis, diabetes, pregnancy or wrist trauma. Women are three times more likely to develop CTS than men, and it is rare in children. Most of the time no cause is found. The space that the median nerve traverses is very tiny and it doesn’t take much to compress the nerve. Even small amounts of tissue swelling such as occurs in pregnancy can cause severe symptoms.
The treatment for Carpal Tunnel Syndrome starts with Read more »
For this week’s CBS Doc Dot Com segment, I thought I’d cover something completely non-controversial: what can weekend warriors learn from elite athletes? But I’m starting to believe that in this era of evidence-based medicine, nothing may be truly knowable. I went to the studios of the world famous Ballet Hispanico in New York City and spoke to athletic trainer Megan Richardson. She took me through the motions, emphasizing the importance of warming up and stretching in preventing injury. It sounded good and it felt good. But proving in the medical literature that it’s effective is another thing. An online search quickly produced multiple conflicting reports and advice: stretching definitely works, stretching definitely doesn’t work; stretching only works if you do it my way. Click here for a sampling:
My friend and CBS colleague, Richard Schlesinger, offered his solution. ”I get around it by neither stretching nor exercising.” Had I listened to Richard, my blog post would have ended right here. But I figured I needed at least one more paragraph so I contacted a true expert on the subject, Ian Shrier MD, PhD, a specialist in sports medicine and Associate Professor at McGill University. He has a PhD in physiology and is Past-President, Canadian Academy of Sport Medicine. He’s not a huge fan of stretching right before exercise.
“First, the stretching, whether with or without warmup, does not improve performance. It makes you run slower, jump not as high, and makes you weaker.” And “stretching definitely can hurt people if you overstretch; people do it all the time if they force the stretch.”
He added, “I don’t think it hurts you in general if you do it properly but it doesn’t prevent injury.” He’s more supportive of stretching at other times, including after exercise, saying, “Regular stretching at other times is beneficial. It makes you stronger, jump higher, etc, and there are three studies suggesting it reduces injuries as well, although the results were only significant in one.” He adds that “stretching is analgesic; it allows you to put your muscle through a wider range of motion without feeling tension. And that may be why ballerinas say that stretching helps them.” Dr. Shrier spells out his take on the subject in detail in a chapter called
“Does stretching help prevent injuries?”
For me, Dr. Shrier’s most interesting advice, especially for weekend warriors, was about the importance of warming up. He explained that muscles need energy to function properly. Energy is mainly produced inside of cells in structures called mitochondria. When you are resting, your mitochondria power down. During exercise, it takes awhile for the cell to rev up the enzymes needed for breaking down fat and carbohydrates for fuel and for using oxygen to make energy from that fuel. If you start running at full speed without warming up, your body will produce lactic acid. Lactic acid can impair muscle function for awhile, preventing you from sprinting efficiently at the end of the race.
So Dr. Shrier suggests gradually warming up. He estimated it takes about 3 to 5 minutes to efficiently go from one level of exercise to the next – for example, going from rest to a ten minute mile or going from a ten minute mile to a seven minute mile. If you go for a jog, “you walk, then jog slowly, and then pick it up. Elite marathoners might go for a fifteen to twenty minute jog before they run a marathon. That allows them to run faster at the beginning of the race. They run the second half of the marathon faster than the first.”
In summary – and I suspect that I am the first person today to tell you this – don’t outpace your mitochondria.
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