Cross-training for fitness

Every time you exercise vigorously your muscles are injured, and the harder you exercise, the longer it takes for your muscles to heal. You are not supposed to exercise vigorously again until your muscles stop hurting. You can exercise hard on one day and easy on the next few days, or you can train in two sports. This is called cross-training, and it can make you very fit and help to prevent injuries.Each sport stresses specific muscle groups. Cycling stresses the upper legs, while rowing stresses your back and upper body. If you cycle and row on the same day, you stress your upper legs and upper body on the same day. To reduce your chances of injuring yourself, you should take the next day off, or at least exercise at a very low intensity....

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Pedal faster to ride better

All cyclists should learn to pedal at a fast cadence, whether you are an experienced racer or a novice recreational rider. Muscle fatigue and damage are caused by excess pressure on the pedals, not by how fast you pedal. Pedaling at a faster cadence with less pressure allows you to pedal longer and harder. However, several researchers have expressed concern that pedaling very fast could decrease blood flow to muscles and thus decrease athletic performance. A study from Kansas State University shows that pedaling fast does not decrease a muscle's flow of blood or ability to extract oxygen from the blood (European Journal of Applied Physiology, March 2006). Once again athletes and coaches find new training and competing methods and years later,...

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Diabetes risk screening tests

The best predictor of diabetes is a test called Hemoglobin A1C (HBA1C), which measures the amount of sugar stuck on cell membranes. At the American Diabetes Association meeting in June 2006, Dr. Peter Baginsky of Santa Rosa, California showed that HBA1C can be used not only to identify people who already have diabetes, but also as a screening test to predict which people are likely to develop diabetes in the future. This allows doctors to treat pre-diabetes before people suffer their heart attacks, strokes and other side effects that can be the first sign that the person has diabetes.He also showed that people who have HBA1Cs above 5.8 have a 92 percent chance of being diabetic as determined by a fasting glucose tolerance test. The HBA1C test...

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Should you restrict all fats?

Almost 50,000 women in the Women's Health Initiative Dietary Modification Trial from Harvard Medical School were given dietary counseling to reduce their fat intake to less than 20 percent of their daily calories (Clinical Diabetes, July 2006). This intense dietary counseling did not reduce the incidence of heart attacks, strokes, or cancers even though the women reduced their intake of fat by 8.2 percent.Their data from the eight-year follow up show that it is difficult to reduce total fat intake, and that dietary counseling to reduce total fat intake does not reduce the risk of heart attacks or cancers. It lowered weight only an average of three pounds and diastolic blood pressure only slightly. However, other studies have shown that reducing...

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How to do sit-ups

Sit-ups can strengthen your belly muscles, but doing them incorrectly can hurt your back. Sit-ups should be done while you lie on your back with your knees bent enough for the soles of your feet to touch the floor. Place both hands on your chest and slowly raise your head off the ground. Raise your shoulders about one foot and then lower them to the ground. Do this slowly ten times, rest a few seconds and then do two more sets of ten. After a week or two this exercise will feel easy, so add a light weight held behind your neck or on your chest. As you become stronger, you can use heavier weights.There's no need to do more than 30 sit-ups in one workout. To strengthen your belly muscles, you increase the resistance, not the number of repetitions....

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Children's exercise

Children need at least 90 minutes of exercise a day to avoid heart disease when they are older, according to a new study reported in Lancet (July 23, 2006). The old guidelines recommending 30 minutes of exercise three times a week, or even an hour a day do not appear to be adequate for preventing obesity and heart disease. Researchers used heart rate monitors to measure the activity of 1700 nine- to-fifteen-year-olds in Denmark, Estonia, and Portugal. They then calculated a heart-attack risk score consisting of blood pressure, cholesterol, insulin resistance, and skinfold thickness.They compared physical activity from the heart rate monitors with the heart attack risk-factor score and found that the more active the child, the lower the heart...

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Sports Drinks or Water?

Drinks that contain salt and sugar are better than just plain water during exercise, unless you are also eating foods. A study from the Medical College of Georgia shows that tennis players have lower body temperatures when they drink fluid with electrolytes and sugar, rather than just plain water (British Journal of Sports Medicine, May 2006). Higher body temperatures during exercise slow you down and tire you earlier. More than 80 percent of the energy that supplies your muscles is lost as heat. Less than 20 percent drives your muscles. So during exercise, your heart has to cool your body by pumping hot blood from your muscles to your skin, as well as pumping oxygen-rich blood to your muscles. If you heart has difficulty serving both functions,...

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Second wind

Second wind means that when you run very fast, you reach a point where you gasp for breath, slow down but keep on pushing and after a few seconds, you feel recovered and pick up the pace. Some people think that you just slow down and allow yourself enough time to recover from your oxygen debt, but research from the University of California in Berkeley may give another explanation.When you run fast, your muscles use large amounts of oxygen to burn carbohydrate, fat and protein for energy. If you run so fast that your lungs cannot supply all the oxygen that you need, you develop an oxygen debt that causes lactic acid to accumulate in your muscles to make them burn, and you gasp for air. The muscle burning and shortness of breath caused by the...

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Marathon training

Many runners have the mistaken impression that they have to run a lot of miles every week to be able to run fast in a marathon. Most will find that running too many miles slows them down. To run fast in races, you have to run very fast in practice. However, on the day after you run very fast, your muscles will feel sore. If you run fast while you are sore, you are likely to injure yourself and not be able to run at all. Take easy workouts until your muscles feel fresh again. Most competitive runners set up their programs so that they run fast on Tuesdays and Thursdays and longer on Sundays. The rest of the time they run slowly or not at all.Before you increase the intensity of your running program or any other exercise, check with your doctor....

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Exercise prolongs life

Dr. Todd Manini of the National Institute on Aging reports that older active people who walk, climb stairs, do household chores, or even wash windows are 69 percent less likely to die in a year, compared to people who are far less active (JAMA, June 2006). This study was far more dependable than previous studies because, instead of using a questionnaire, researchers measured how active a person was by measuring the metabolic end products of activity. They used a doubly-labeled water method that directly measures carbon dioxide production over an extended period, the most accurate estimate of energy expenditure. If you are inactive, you should check with a cardiologist who will do a stress test. If you pass, you should start an exercise program....

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Weight lifting helps to prevent diabetes

One third of Americans will become diabetic because they eat too much and exercise too little. A study in Medicine and Science in Sports and Exercise (July 2006) shows that lifting weights can help to prevent and to treat diabetes.Extra fat prevents your body from responding normally to insulin. Before insulin can do its job of driving sugar from the bloodstream into cells, it must first attach to little hooks on cell membranes called insulin receptors. Having extra fat in cells turns these receptors inward, making it far more difficult for insulin to attach to the receptors. This prevents insulin from doing its job of lowering blood sugar levels, even though your body is making plenty of insulin. That’s why anything that makes you fat increases...

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Dizziness on changing position

Athletes and other very fit people may feel dizzy when they rise from lying to standing because of their slow pulse rates. Exercise makes your heart stronger so it can pump more blood with each beat and it doesn't have to beat as often. A slow pulse rate can be good. Since your heart doesn't beat as often, it has more time to rest between beats. Like a low-mileage used car, perhaps this will mean it takes longer to wear out. But a slow heart rate can make you dizzy when you change position. When you raise yourself from lying to sitting, or from sitting to standing, the force of gravity pulls blood down from your brain towards your feet and your blood can't get back to your brain until your next heart beat. If you have a pulse rate of only 50...

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Rosacea: red in the face

Many people develop a red scaly rash on their faces as they age, particularly in the center on the nose and cheeks. They flush or blush and often also have small acne-like bumps on their faces, swollen noses and prominent red blood vessels. Sometimes, this same rash may extend to the shoulders, chest and back. It's called rosacea.Nobody knows what causes rosacea, but most doctors feel that it is a genetic disorder associated with other skin conditions, seborrheic dermatitis and psoriasis. They may also have terrible dandruff, scaly ears, thick big toe nails, and sometimes thick skin on their elbows and knees. The recommended treatment is to take an antibiotic such as doxycycline 100 mg twice a day plus an antibiotic cream such as metronidazole...

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Caffeine

Two recent studies show that too much caffeine may cause problems for some people. Researchers at Queens University in Kingston, Ontario report that caffeine, in coffee, tea, chocolate, and most colas, raises blood sugar levels in healthy people and diabetics, which cannot be reversed by exercise or weight loss (1).When you eat, your blood sugar level rises. If it rises too high, sugar sticks to cells, and once stuck on cells, it is converted to sorbitol which destroys the cell to increase risk for heart attacks, strokes, blindness, deafness, kidney failure and other effects of diabetes. Anything that increases blood sugar levels increases risk for diabetes. So, most doctors recommend restricting refined carbohydrates, in sugar and flour. Exercise...

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How to Warm Up

Warming up before you exercise helps to prevent injuries and lets you jump higher, run faster, lift heavier or throw further. Your warm-up should involve the same muscles and motions you plan to use in your sport. For example, before you start to run very fast, do a series of runs of gradually-increasing intensity to increase the circulation of blood to the muscles you will be using. Muscles are made up of millions of individual fibers, just like a rope made from many threads. When you start to exercise at a very slow pace, you increase the blood flow to muscle fibers, increase their temperature, and bring in more oxygen, so the muscles are more pliable and resistant to injury. When you contract a muscle for the first time, you use less than...

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Bonking: low blood sugar

Yes, I know the word has another meaning. But in sports, bonking is running out of blood sugar. If you watch a major bicycle race on TV, you have to be impressed by how the riders can eat enough to sustain them through races that require more than five hours of near maximum effort. If a rider does not get enough food during his or her ride, he can fall off the bikes, lie on the ground unconscious and start to shake all over in a in a massive convulsion. This is called bonking, or passing out from low blood sugar. Your brain gets almost all of its fuel from sugar in your bloodstream. When your blood sugar level drops, your brain cannot get enough fuel to function properly, you feel tired and confused and can pass out. There is only enough...

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Belly fat: why it's dangerous

Storing fat primarily in your belly increases your chances of suffering heart attacks and diabetes. When you take in more calories than your body needs, your liver turns them into fat. Fat cells in your belly are different from those in your hips. The blood that flows from belly fat goes directly to your liver, whereas the blood that flows from your hips goes into your general circulation. The livers of those who store fat in their bellies are blocked from removing insulin by the extra fat and therefore do not remove insulin from the bloodstream as effectively as the livers of those who store fat in their hips and have less fat in their livers.People who store fat primarily in their bellies are called apples, while those who store fat primarily...

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Interval training

To become stronger and faster, athletes use a technique called interval training, in which they exercise very intensely, rest and then alternate intense bursts of exercise and rest until their muscles start to feel heavy. Intervals are a fixed number of repeats of a fixed distance at a fixed pace with a fixed recovery time. There are two types of intervals: long and short. A short interval takes less than 30 seconds and does not build up significant amounts of lactic acid in the bloodstream, so an athlete can do lots of repeat short intervals in a single workout.Long intervals take two minutes or more and are very tiring. In interval training, a runner may run a quarter mile 12 times, averaging 1 minute, with a 110-yard slow jog between each....

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Warm up your heart

Most people know that you have to warm up skeletal muscles to help protect them from injury, but many do not know that warming up the heart muscle also helps to prevent heart attacks in people with blocked arteries leading to the heart.Before you try to run very fast, you can protect your muscles from injury by performing a series of runs of gradually-increasing intensity to increase the circulation of blood to your muscles. The same principle applies to the heart. Angina is a condition in which the blood vessels leading to the heart are partially blocked so the person has no pain at rest, but during exercise, the blocked arteries don't permit enough blood to get through to the heart muscles, causing pain. A study from the Quebec Heart Institute...

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