Three Common Swimming and SCUBA Myths in the News Again

On Monday July 7, a news show Troubled Waters featured a story of two scuba divers who floated 19 hours overnight after they and their dive boat did not connect after a dive on the Great Barrier Reef in Australia.

In their television interview, the two divers told various points of the situation. Three of the concerns were common myths often repeated in scuba training.

1. They mentioned they experienced signs of hypothermia. Technically, not any chilling is hypothermia. Being uncomfortably cold does not mean you have hypothermia. Shivering and teeth chattering does not mean you have hypothermia. You can even become incapacitated by cold before becoming hypothermic. In informal conversation, the two terms of hypothermia and chilling are often used interchangeably.

2. The woman of the pair stated she had read in a book, which had a section about progression of hypothermia, that exercise is not good and can be counterproductive. They were worried that body movement would, "send blood to the muscles away from your core, and your organs" and for that reason, make them colder.

I have read the book they mention. It is a book of wonderful stories and great writing, interesting medicine, but the physiology is frequently off. As a physiologist, I notice these things. When I teach medical students in their classes, I often see that they do not want to learn physiology, they only want to learn what medicine to give and where to cut. I tell them that without understanding the reasons for how the body resulted in the situation in the first place, they will only repeat the mistakes of their teachers by giving medicines and cutting.

Back to the shivering divers floating all night, waiting for rescue. It is not always the case that exercise in the cold must only make you colder. Exercise in cold water can generate enough heat to match or surpass the large thermal drain, depending on water temperature, work load, duration of exposure, your body composition, what you are wearing, and other factors. It is true that exercise in cold water increases heat loss, but it is an important point that it does not mean that you will always cool. Whether you stay comfortable or get cold depends how much heat you keep and how much you lose. If you generate more heat than you lose, you will be warmer than when you started. When I worked on cold water immersion for the Navy, we studied body cooling in pilots downed in cold water, and how long they could survive (all volunteers, really they loved my studies). We also studied divers. Some divers sent for underwater missions during the Gulf War were overheating underwater and had to wear ice vests with their scuba gear.

3. The last myth is a popular one. I am a scuba instructor and have heard this one repeated often. The two divers mentioned that the woman of the pair was menstruating and that there were sharks in the water. The woman said, "I'm shark bait is what I'm thinking." Diver researcher Dr. Carl Edmonds found that Australia's shark attack tracking system reported nine times more shark attacks on men, even though there was an even number of male and female swimmers.

Menstrual blood does not attract sharks. Neither does menstrual blood attract grizzly bears during camping trips, cause wine to sour as stated in ancient religious writings, or cause wings to snap off airplanes, as pilots insisted in the 1920's. The term man-eating shark, for now, remains.

I explain these myths and more about swimming and diving physiology, underwater and in heat and cold, in the book Diving Physiology in Plain English.

Labels: cold, myths, scuba, swimming

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Summer Olympics 2008 Coming

The summer Olympics will begin this August. The Olympics are an international cooperative athletic contest held every two years, alternating winter and summer Games. Before 1992, the summer and winter games were held in the summer and winter of the same year, so that four years passed between each Olympic year, called an Olympiad.

Estimates on the date of the first recorded Olympic Games in ancient Greece vary around the early 800's BC, with indications of regular games held far earlier. The first events were foot races. Soon wrestling and the pentathlon (five events by one athlete) were added. More events followed.

The games and ceremonies emphasized reverence to heaven, ability of body and mind, plus nakedness and deliberate gore for the ratings (popularity). Olympics continued in Greece every four years for about a thousand years. After the Romans gained power in Greece, Emperor Theodosius I outlawed the Olympics in the year 393 AD because they weren't Christian.

Fifteen hundred years passed. In 1894 the International Olympic Committee (IOC) was founded to rekindle the Olympic games. In 1896, the first modern Summer Olympics was held in Athens Greece. Fourteen nations participated track and field, fencing, weightlifting, rifle and pistol shooting, tennis, cycling, swimming, gymnastics, and wrestling. No women were allowed to compete. The IOC director stated that including women would be, "impractical, uninteresting, unaesthetic, and incorrect."

The following Olympics in Paris in 1900 allowed eleven women to compete in lawn tennis and golf. This August, it is projected that athletes will compete in 302 events in 28 different sports. At the 2006 Winter Olympics in Turin Italy there were 84 events in 7 sports. Currently, 203 countries participate in the Olympics. This is higher than the 193 countries who presently belong to the United Nations.

There are debates whether countries or heads of state should boycott Olympics to make influential political statements. Several boycotts have been held by various countries over several Olympics. In many Olympic years, different political topics from war, to the interpersonal war of apartheid, to the status of the country of Taiwan, have been focus for boycott. This year it is position of the country of Tibet in relation to the host country of China. As one of the swimmers who felt the impact of the 1980 boycott because of events in Afghanistan, I know it is a difficult thing to decide either way. Consider this: today, Olympics are boycotted over wars. In ancient Greece, wars were postponed and ceasefires called to observe and honor the Olympics.

Labels: mind, Olympics, spirit

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Fast Fitness - Freedom for All on the 4th of July

Here is Friday Fast Fitness - Remember freedom for all people and for Earth on America's Independence Day.

1. Reduce toxic waste from discarded batteries. Jacqueline Meier of Switzerland is creator of the Clean Planet Association. Part of this work is the Clean Kaïlash Project.
2. Donate blood - Blood Hero.
3. Build a school - Three Cups of Tea.

Click Independence Day for Fitness for ideas for personal freedom from bad foods, drugs, injuries, and physical and mental pain.

The Fitness Fixer wishes everyone a happy 4th of July.

Labels: fast fitness, holiday, mind, spirit

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Fixing Posture - No Exercises Needed

A widespread myth is that to fix posture you must strengthen sets of muscles.

After spending time and money on strengthening exercises, people often wind up as stronger people with the same poor body position. The fallacy is that strengthening does not create movement. You do that yourself.

A physician wrote me that he has hyperlordosis from surfing, and is "working" to fix it. He had spent much time waiting for the exercises to "work." What he missed is that surfing does not cause it, and how you stand can be fixed there and then by deliberately, volitionally changing how you stand. How? Try Friday Fast Fitness - Neutral Spine in 5 Seconds.


In the comments to the post Prevent Main Factor in Back Pain After Running and Walking, a Division I athlete wrote:

"Thank you. I am a D1 athlete and have been struggling with back pain/extreme tightness when lifting and playing in the same day. I have known I had bad posture while running/walking for about 4 years, went to physical therapy for it, and still haven't changed it. I kept waiting for a certain exercise to suddenly "fix" me. Duh, what fixes me is ME CHANGING IT. Shocking."

When certain muscles are tight, it can feel normal to stand badly. Even though it is popular to talk about tight hamstrings changing posture, that is mostly an issue when sitting. When standing, two tight areas are most common, chest and front hip:

• Tight front chest muscles make round-shouldered position feel normal. Round-shouldered positioning keeps the front muscles shortened, in a cycle of shortening and tightening. The upper back muscles over-lengthen. This is why the most common stretch of pulling an arm over the front of the body is usually counterproductive. To fix anterior (front) tightness start with understanding and doing the pectoral stretch, described in Fixing Upper Back and Neck Pain and stop promoting an already overstretched posterior shoulder with The Stretch You Need The Least.
  

• Tight front hip muscles make standing badly feel normal. The front of the hip is pulled downward, tipping the backside outward in back. The lower back increases in inward curve in a painful posture called swayback or hyperlordosis. Many people stand this way without knowing it because they think standing with the hip tilted forward in front is normal or "cute." Much of modern conventional "fitness" encourages this unhealthy, unattractive bad posture.

Hyperlordosis is a major hidden factor in lower back pain. People may undergo months, even years of treatments, adjustments, shots, medicines, therapies for discs, sciatica, facet pain, and other pain without knowing or changing the cause - allowing a too large an inward curve to the lower back.

The photo at right demonstrates an over-arch in the lower spine, the hip tilted forward in front, and a forward head while doing an activity supposed to be for health. It seems impractical to do "fitness" in unhealthy ways. Moreover, tilting the hip forward reduces the Achilles stretch and reinforces bad movement habits. For a more functional Achilles stretch try Better Achilles Tendon Stretch.

Hyperlordosis is not a medical condition or unchangeable anatomy. It is simple bad posture that you can allow or change right as you stand. Neutral spine is not pushing the hip forward, just moving it enough to make it level. See a short movie in the post Friday Fast Fitness - Neutral Spine in 5 Seconds. To stretch the front hip, try these:

1. Fast Fitness - Quick Relaxing Hip Stretch.
2. Change the common ineffective way to stretch the front of the thigh and hip with Instantly Better Hip and Quadriceps Stretch
3. and Stretch While You Strengthen Legs.
   

Watch other people when they exercise, walk, and run. See how often you can spot the unhealthy overarched lower spine. See what to look for in the post Spotting Back Pain During Running and Walking - What Do Abs Have To Do With It?

Remember that stretching the hip and shoulder, and anywhere else, will not automatically make you stand right. You do that yourself using your own muscles and brain. Free exercise. Free fix.

Labels: fix pain, lordosis, lower back, posture, stretch

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Thank You IPhone 3G Grand Rounds

Thank-you to MyThreeShrinks at Shrink Rap for hosting Grand Rounds volume 4.40 last week with an IPhone 3G theme.

They included my post Is Your Drinking Hurting Your Neck? among their votes for the best medical posts of the week. The post shows how to prevent neck pain from drinking, eating, and talking on the phone, and healthier, range of motion and use of neck muscles.

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