Potential health problems resulting from secondhand smoke include: lung cancer, heart attacks, low infant birth weight, SIDS, bronchitis, pneumonia, asthma, chronic respiratory problems, eye and nasal irritation, and middle ear infections (otitis media). And unfortunately, children are particularly vulnerable to these conditions.
Secondhand smoke contains twice as much tar and nicotine as is inhaled smoke from a cigarette. In addition, secondhand smoke contains three times the amount of "3,4 benzpyrene" (cancer-causing), five times more carbon monoxide, and possibly 50 times as much ammonia. And second-hand smoke from pipes and cigars is as bad as or worse than that from cigarettes.
Cigarette smoke is ubiquitous; the April 24, 1996, issue of the Journal of the American Medical Association reported that serum cotinine (a breakdown product of nicotine) was found in nine out of every 10 nonsmokers in a large nationally representative sample. It was also found that more than 40% of children between the ages of two months and 11 years live at home with a smoker.
The National Academy of Sciences, The U.S. Surgeon General, the Environmental Protection Agency, and a number of professional medical associations have declared that secondhand smoke causes lung cancer in nonsmokers.
In the case of heart attacks, a study of 32,000 nurses revealed that exposure to secondhand smoke doubles a woman's risk of having a heart attack; published in the medical journal Circulation, in May 1997.
Harmful affects on children include:
There is what I think is a myth about water intake. That is that "warm" water is best. Water (fluids in general) serves many purposes in the body, but in an exercising body, cooling is of significant importance. Cooling is best done by water near 40-41° F. Cold water results in gastric emptying faster than water at body temperature, and without causing stomach cramps as is sometimes thought. The temperature of fluids for purposes other than cooling may be at a much warmer temperature.
The effects of exercise on mitochondria (energy storehouses, as you remember) does not seem to be really well known- especially the effects of strength training.
Few studies have concentrated on the effect of resistance training on mitochondria, but similar to the effect on capillarization, mitochondrial density decreases with heavy weight training (like power lifters). Body builders, who use lighter weight and more reps, actually have an increase in capillarization and an increase in a mitochondrial enzyme. Whether this applies to mitochondrial density or not seems to be an open question. To date, the effects of resistance training on mitochondria seems to be somewhat of a mystery, the result of too little study.
In the case of endurance training, mitochondrial adaptation manifests itself in an increase in mitochondrial enzyme activity. Detraining results in reduced enzyme activity, and in a big way. The half life of the mitochondrial enzyme is 12 days, which means that 12 days of detraining requires at least 36 days of retraining to return to previous levels. The restoration of earlier adaptations is about 3:1. Clearly, complete cessation of training results in a severe setback.
Unfortunately, my original question - what are the effects of resistance training on mitochondria remains unanswered - it is still ambiguous in my mind.
Just after this article was completed, W.J. Evans, the Director of the Nutrition, Metabolism, and Exercise Division of the University of Arkansas for Medical Sciences, responded to a question posed to him about strength training's effects on mitochondria. His response was as follows: We found that high intensity resistance training increases capillary density, a mitochondrial enzyme, and maximal aerobic capacity in older men. [His statement is based on the paper "Strength training and determinants of VO2 max in older men. J Appl Physiol 68(1):329-333, 1990; authored by Frontera, Meredith, O'Reilly, and Evans. Since Dr Evans is known to have been involved in research on sarcopenia (strength loss due to aging), I suspect that the above identified paper came from said research.]
Another reference just surfaced: the book "Exercise Physiology" by McArdle, Katch, and Katch says that anaerobic training increases resting levels of anaerobic substrates and key glycolitic enzymes. Usually accompanied by increases in maximal exercise performance. Aerobic training increases mitochondrial size and number as well as activity of aerobic enzymes, increased capillarization of the trained muscle, and enhanced oxidation of fat and carbohydrate. The result is a greater aerobic production of ATP [the ultimate source of energy ].
We have some answers to our question, but the book is not closed in my mind.
Is weight loss best accomplished by aerobic or anaerobic exercise?
A few days ago I saw a brief exchange of e-mail messages about exercise mode and weight loss. The first person said, more-or-less, that weight loss could be best achieved by lots of aerobic exercise, with some weight training. [And dietary changes, but I don't remember if that was included or not.] Number 2 came along and said, more-or-less, not to discount anaerobic exercise's contribution to weight loss. Intense anaerobic exercise burns calories during exercise, and continues to burn more afterward ("afterburn"), which amounts to about a 15% boost in BMR/RMR for up to about 16 hours depending on length and intensity of the exercise session. It was also mentioned that a high number of calories can be burned doing things like skiing (not cross country) or other primarily anaerobic activities done at high intensity. Athletes, even weekend warriors) might need to consume thousands more calories than normally just to keep up their energy, BUT someone who is looking to trim some bodyfat isn't likely to use high intensity anaerobic sports activities to do it. He or she will logically choose aerobic activities that can be maintained regularly and for a longer duration. [And yes, I know skiing or whatever can be done all day long, but not commonly continuously or daily.]
So, what about those sprinters, body builders, whatevers, that are lean and muscular and do no aerobic training to speak of - mostly anaerobic? They look the way they do, I think, because they choose their sport mainly based on thir genetic attributes - those with small frames and abundant slow twitch muscle fibers aren't likely to choose to be body builders or sprinters; just like a big-boned wellmuscled (lots of fast twitch muscle fibers) individual isn't likely to choose to be an endurance athlete.
Anyway, my point is that aerobic training should be the first choice for most people looking to decrease body fat. Anaerobic training works for some people that don't need to lose 50 or 100 pounds. Their high number of calories burned must be replaced to maintain an energy level that will sustain intense workouts. Calories burned during anaerobic exercise, in addition to afterburn, is usually enough to maintain already lean athletes; but isn't a great way to lose excessive body fat. I'm not saying that it can't be done, but that it would be a rare exception.
Olestra: is it all that we hope it might be? Maybe not. In a report contained in the 13 Aug 1998, Kansas State University Health and Fitness News, the headline read Olestra is a Double-Edged Sword: Cuts Fat But Also Vitamins.
It went on to state that Olestra did reduce fat, as it was designed to do; but it can also decrease vitamins and cancer-fighting caratenoids in your body.
Chemically, Olestra is a sucrose polyester. The "ester" components are oils extracted mainly from soybean and cottonseed oils. What we have is essentially a fat molecule that can't be absorbed in the GI tract (it is too big), and therefor passes right through the digestive tube.
Some previously known side effects of Olestra are abdominal cramping and diarrhea - uncomfortable, but not normally particularly serious. However, in the long term, overconsumption of Olestra-containing products are potentially much more serious.
The long term effect is unknown, but because of the large size of Olestra molecules, as they pass through the body they carry along some of the fat soluble vitamins (A,D,E, and K), and possibly some other nutrients like alpha and beta carotine and lycopene (antioxidants - potential cancer fighters).
Olestra containing foods (chips, for example) are fortified with vitamins A, D, E, and K, but nothing else. [So, the problem is seemingly recognized, but only partially fixed.]
In addition to the potential nutrient loss due to the use of Olestra, there is the fact that people tend to OD on fat free products (fat free, but not calorie free), so it may provide a double-whammy - nutrient loss, and a rise in the fattening of America.
So, you need to top off your calcium intake. Try some figs. That's right, three or four of them supply about 100 milligrams of calcium. I don't recommend getting your daily allotment from this source - you wouldn't get out of the bathroom all day - but figs are just one more item that can be added to milk and dairy products, soy products, rice milk, brocolli, sardines, etc. Figs are also high in phosphorus which, along with vitamin D, aids calcium absorption.
Exercise and osteoporosis has long been linked. Research has shown that exercise can help to prevent osteoporosis, as well as treat it. Osteoporosis can cause the vertebrae in your spine to compress, potentially resulting in "stooped" posture and greater risk of bone fractures (commonly of the hip). Hip fractures are known to cause falls, which may result in any number of unpleasant eventualities - even death.
To prevent osteoporosis, exercise, consume adequate calcium, and vitamin D, and don't smoke, and for women, consider some form of hormone replacement therapy during and after menopause.
Exercise is a strong weapon in the battle against osteoporosis by minimizing mineral loss, but also by strengthening muscles to promote good posture and improving general fitness, all of which help to mitigate against falls.
A proper exercise regimen includes 1) weight-bearing activities like walking, jogging, and stair climbing; 2) weightlifting, alternately called resistance training or strength training; and 3) back-strengthening exercises.
Weight-bearing exercise
Weight-bearing exercise, like walking, jogging, or stair climbing, stresses the hips, legs, and lower spine; and tends to minimize bone loss; and if you already have osteoporosis, this exercise mode can help to minimize bone loss. And walking at least a mile a day is highly recommended - it is effective, but with limited jarrng of bones/joints.
Weightlifting
Weightlifting contributes to healthy bones by strengthening muscles and bones of the upper and lower body, and the spine, especially the upper spine.
Back-strengthening Exercises
These exercises also stress bones, but are important for strengthening muscles that facilitate correct posture, which helps treat osteoporosis by fighting the "stooped" posture tendency that can result in compression fractures of the spine. The following exercises are recommended (By whom I don't know. They are fairly gentle, but stop if they cause any pain.):
Now that what conventional wisdom says about exercise and osteoporosis has been reiterated, let's take a look at a slightly different perspective provided by Christine Snow, an exercise physiologist who is the director of the Bone Research Laboratory at Oregon State University. She talks about athletes who subject their bodies to high amounts of physical stress, like wrestlers or gymnasts who add up to 30% more mass to their hips than, say, competitive runners. Runner's feet hit the ground with about three times their body weight, but gymnasts or wrestlers can shock their bodies with up to 12 to 15 times their body weight, and their bones get much stronger as a result.
Studies show that exercise and sufficient calcium and vitamin D (and maybe estrogen for menopausal/post-menopausal women) will help maintain strong bones throughout a lifetime.
A frightening statistic is that 20% of elderly women who have hip fractures die within a year of the injury. Ms Snow estimates that it takes an impact of at least three times your body weight to make a difference for your hips, which puts jogging/running on the edge of efficacy. Walking, often called the perfect exercise, on the other hand, produces only one-and-a-half times your body weight. Enough to slow down bone loss, but not enough to increase bone density.
But, walking definitely improves cardiovascular fitness, so don't eschoo it. But you could benefit from adding higher impact exercise three to five times a week. An excellent way to upgrade your walking is to add hill training - on trails, if possible. Direction changes, ups-and-downs, moving over obstacles; all increase the stress on your hips, and they get stronger.
Other good alternatives are to incorporate bounding/bouncing activities into your exercise program, and things like step aerobics, stair climbing (use real stairs), volleyball, basketball, or racquet sports. Plain old jumping can be very effective - vertical jumping, jumping rope, maybe some plyometric jumps.
Ms Snow has conducted a study where the subjects started out with five to eight jumps, three to five days a week; and included stretching and strengthening exercises to strengthen the jumping muscles - squats and lunges to prepare the knees for the stress. As time passed, the jumping maxed out at 50 per session. The program that she designed included forward and side lunges, squats and chair raises (Sit on the edge of a chair, with your feet widely spaced; then slowly stand up without using your hands - that's one. And you may stick your arms out to help with balance.), heel and toe raises, and jumps.
In addition, she added some upper body weight training to strengthen the spine. She recommends using some heavy weights, like 70-90% of your maximum. She says that you shouldn't be able to do more than six to eight reps. You should at least sprinkle some heavy sets in your program - vary the heavy sets between different body parts from session-to-session.
(Q) If fiber isn't a nutrient, why do we need it?
M.K., Sunnyvale, CA
(A) Fiber is not a nutrient, but it is an important component of a diet. It comes in two forms - soluble and insoluble. There is evidence to support the idea that soluble fiber lowers blood cholesterol, thereby reducing the risk of heart disease. Insoluble fiber softens stools thereby preventing constipation, and aiding transit of dietary refuse through the digestive tube. There is also evidence that it helps protect against the disease diverticulitis.
(Q) Is there any advantage to using ice massage over an ice bag?
M.N.F., Union City, CA
(A) Ice massage works faster, although both methods eventually reach the same temperature. Many athletic trainers like to use ice made by freezing water in a paper cup, then applying it from the bottom side and peeling away the paper as the ice melts. The idea is that the thin layer of paper at the bottom of the cup might protect the skin; however, I was once told by a physical therapist that applying ice directly to the skin is safe, as opposed to chemical ice, which can damage the skin if applied directly.
(Q) What is a SERM? And what does it have to do with breast cancer?
B.L., Los Altos, CA
(A) A SERM (selective estrogen-receptor modulator) is a synthetic compound that simulates estrogen in certain tissues, but effectively locks it out in others - like breast tissue. It is also effective as an antiosteoporosis agent. The first SERM available is raloxifene (Evista), but some doctors have questions about its pre-FDA-approval-testing, and won't prescribe it without further testing.
(Q) I have shin splints that just won't go away. I have used ice and rest and, have done ankle flexion exercises that have been recommended, but without success. What else can I do?
R.J., Potlatch, ID
(A) Your shin splints might actually be a stress fracture. Shin splints should normally respond to ice therapy, rest, and the exercises that you mentioned. Active rest works for healing a stress fracture. Instead of trying to continue with the sport that resulted in the problem, switch to something like swimming or stationary cycling to maintain fitness.
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