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The Health Benefits of Exercise

Why should we exercise? People who exercise regularly have a lower death rate than sedentary people, regardless of their weight.[1,4,5]  Exercise stretches and contracts the muscles and stimulates breathing thereby improving blood circulation and lung function. Exercise has also been shown to improve insulin sensitivity for healthy persons and those with non-insulin dependent diabetes mellitus (Type II diabetes).[2] Weight-bearing exercises also strengthen bones and may help decrease the risk of osteoporotic fractures.[7]

Walking is good exercise 
Walking can burn
300 Calories/hour 

Don't expect to lose a lot of weight by exercising. Many people believe that exercise is a good way to lose weight. This is not so. Fifteen minutes of moderately vigorous exercise will only burn approximately 100 calories, which is equivalent to 2 teaspoons of olive oil or two-thirds of a can of soda. One hour of walking at a brisk pace will burn about 300 calories, which is equivalent to a 3.5 oz. (100g) plain croissant. Running a 20-mile marathon does not burn enough calories to lose one pound of fat. You need 10 hours of moderate exercise to burn the calories equivalent to one pound of fat, but you cannot selectively burn only fat. Most of the weight lost by exercising is due to dehydration (sweat or perspiration), and this weight is regained as soon as you drink water.

The best way to lose body fat weight is through diet as discussed in the Weight Control section. Dieting alone reduces fat and bone mass, whereas dieting in combination with exercise stimulates muscle growth, shifts the ratio of fat to muscle in the body, and helps maintain bone density during weight loss.[6]  Regular exercise lowers the risk of developing or dying from heart disease, stroke and diabetes. Exercise builds bones, strengthens muscles, expands lung capacity and helps prevent gain of excess weight. In addition, exercise induces the release of endorphins which improve mood and produce a feeling of well-being. Approximately 30 minutes per day of vigorous aerobic exercise has been shown to be an efficacious treatment for mild to moderate major depressive disorder (MDD).[9]  The objectives of exercise are:

Don't Overdo It. Excessive or improper exercise may damage the body. In their eagerness to get fast results, many people set unrealistic fitness goals and, by overtraining, suffer injuries which worsen their health instead of improving it. Lifting heavy weights or doing too many repetitions of an exercise can be harmful. We don't need to look further than President George W. Bush to learn what NOT to do. After years of running three miles in 21 minutes, his knees were ruined from the high impact exercise. In 1997, he had arthroscopic surgery to repair cartilage damage to his left knee and in 2003, at age 57, the White House reported that President Bush had "post-traumatic degenerative changes" of his right knee and had to switch to lower impact exercises. Professional athletes usually have short careers due to injuries suffered by trying to perform at the limits of their capacity and end up with chronic pains and injuries that diminish the quality of life.  Almost daily, there are newspaper stories about players who are sidelined because of sport injuries. According to a U.S. Consumer Product Safety Commission report, sports injuries among baby boomers increased by 33 percent from 1991 to 1998.[3]  In 1998, baby boomers suffered more that 1 million sports injuries which cost over $18.7 billion Dollars in medical expenses. The highest numbers of sports-related injuries came from bicycling, basketball, baseball, and running. The most common injuries were due to accidents or overuse, and affected the knees, ankles, lower back, and shoulders.

If you lift weights for fitness, the weights should not exceed 30% to 40% of a normal body weight. Lifting heavy weights compresses the discs of the spine; twisting and turning while lifting or using your back muscles instead of your leg and thigh muscles to lift large, heavy objects can lead to a herniated disk and a lifetime of back pain. If you weigh 150 pounds, you should not exercise with more than 60 pounds of weights because as you age, the spinal discs are not as flexible and the risk of a back injury increases.

Before starting an exercise program, consult a physician. This is particularly important if you have any physical conditions, such as hernias, that may be aggravated by stressing the muscles. Also, any medical problems, like Heart Disease or Diabetes, may require special monitoring by a doctor. Exercise should be done in moderation, not as a competitive sport or as a challenge to find the limits of your stamina or strength because at the limits something always breaks. Heroic efforts should be reserved for when you need to save a life or escape from danger.

To be effective, moderate exercise must be a permanent part of your life. It has to be done every day, or at least five days per week, for the rest of your life. If you don't enjoy exercising, it will be very difficult to have a daily routine that includes it. When you start exercising on a regular basis, you will notice that you have more energy, you can breathe better, and you will actually feel healthier. Once you feel the benefits of exercise, it will be easier to see the wisdom of establishing a workout routine as part of your daily life. A good way to stay in shape is to use elliptical machines because they exercise the legs and the torso while avoiding impacts to the joints.

     

Fifteen Minutes -- Twice a Day.

Exercising fifteen minutes in the morning and fifteen minutes in the evening can improve the way that you feel. It is better if you exercise when your stomach is not full, such as before breakfast and one hour before going to sleep. Some people believe that the only way to exercise properly is by jogging outdoors or by going to a gymnasium or club. This way of thinking only makes it easier to skip exercising when the weather is bad or when you don't feel like changing into suitable attire. You can exercise effectively at home with very simple equipment in the time that it would take you just to go to a gym. All that you need is a set of dumbbells, a foam rubber mat, and a towel. Place the rubber mat on the floor and cover it with the towel. The towel keeps the rubber mat clean and can be washed when necessary.

Dress comfortably when you exercise. Your clothing should give you complete freedom of movement. It should not pull or chafe, and it should allow perspiration to evaporate to keep you from getting soggy. Your shoes and socks should be soft and fit properly to avoid blisters when you walk or run. When you exercise at home, you don't need to impress anybody. An old T-shirt and some gym shorts will work just as well as the latest fashion from Nike or Adidas.

   

Breathe deeply! One of the purposes of exercise is to circulate oxygenated blood through all the organs of the body. Breathe deeply when you exercise. Don't smoke and don't exercise in areas with heavy air pollution; your body will absorb a larger dose of noxious contaminants when you breathe dirty air deeply. The airways of the lungs are lined with mucus membranes and with tiny hairs called cilia that sweep out the mucus along with trapped particles. Breathing fresh air deeply stimulates the body to clean the respiratory passages properly.

Listen to your body when you exercise. If you are thirsty, drink water. If you sweat a lot, drink water with a little bit of salt to replenish the electrolytes lost through perspiration. If something hurts, stop exercising. If your muscles are sore from exercising the previous day, reduce the number of repetitions. Soreness will often go away as your muscles warm up when you exercise. If you run out of breath, stop exercising but continue breathing deeply. You run out of breath when your cardiovascular or pulmonary system cannot keep up with your muscular activity. Continue exercising after you can breathe normally. Your circulatory system and lungs will adapt to service your muscles more effectively when you exercise regularly.

Here are some calisthenic exercises that avoid exposing your joints to harmful repetitive impacts and help to strengthen the major muscles of the body. These typical exercises add up to 11 minutes. Rest one minute breathing deeply between each different exercise.

If you are not strong enough to do the pushups, try a less strenuous pushup by pivoting from your knees. Your arms lift approximately 50% of your body weight for this type of pushup. When you build up your strength, you can start doing the regular pushups. Similarly, if you cannot complete all the repetitions of one exercise, do as many as you can and stop. Over time you will gain strength and you will be able to increase the number of repetitions.

Aerobic Training vs. Resistance Training. Aerobic training, also called cardio training, is any exercise that repetitively contracts large muscles and raises the heart rate above normal resting levels for 15 minutes or longer. Resistance training or strength training is any technique that uses resistance to increase muscular strength. This can be accomplished by the use of exercise equipment, weights, or by lifting your body against the force of gravity. A circuit-training strategy of doing various strength training exercises for different muscle groups in quick succession meets all of the criteria of aerobic training. The sequence of exercises described above places a prolonged increase demand on the heart, lungs and vascular network which is aerobic in nature and also provides strength-training stimulus for all of the muscle groups involved.

Target Heart Rate Calculation
To get a good workout while avoiding overexertion requires monitoring the heart rate. An estimate of the appropriate target heart rate can be obtained using the Karvonen formula.[8]

Maximum Heart Rate = 220 - Age
Heart Rate Reserve = Maximum Heart Rate - Resting Heart Rate
Training Heart Rate = Intensity × Heart Rate Reserve + Resting Heart Rate

The Resting Heart Rate is determined by taking your pulse and counting the number of heart beats in one minute prior to getting out of bed in the morning. The average of three days should be used to get a representative value (add the counts for three days, and divide the total by three). A person with an average fitness level should use intensity levels of 60 to 70 percent of the Heart Rate Reserve.

Target Heart Rate Calculator
 Age
 Resting Heart Rate
 Intensity
   

Maximum Heart Rate   
Heart Rate Reserve   
Training Heart Rate  

Bodybuilding? The exercises suggested here are more like warm-up exercises rather than military fitness or bodybuilding exercises. Military fitness requires approximately double the number of repetitions indicated here, plus running two miles in about 16 minutes. Bodybuilders normally exercise to exhaustion with heavy weights and then allow the muscles to rest one or more days. The muscle exhaustion stimulates muscle growth during the periods of rest if the intake of protein and essential fatty acids is regular, frequent, and sufficient. Bodybuilders may set schedules to exercise specific muscles, e.g., Monday: chest and shoulders, Tuesday: legs, Wednesday: back, Thursday: arms, Friday: abdomen, calves, and forearms, Saturday and Sunday: rest. The curls to build the biceps, for example, are done with dumbbells heavy enough to be able to do a maximum of ten repetitions per set, and the sets are repeated three or four times with short rests in between. The workouts may last from one to two hours. Strenuous exercise or mishandling heavy weights may cause permanent injuries or injuries that take a long time to heal. Bodybuilding should be done only with the help of a qualified personal trainer and a nutritionist.

Bodybuilding and fitness magazines are filled with advertisements of performance enhancement supplements. Besides the beneficial protein and essential fatty acid products, there is a wide array of fat burners, energy boosters, anabolic/androgenic steroid "poppers", and combinations of drugs or herbal products called "stacks". The advertisements usually show pictures of bodybuilders with outstanding musculature or endorsements by famous people to convince you to buy these products. However, for natural bodybuilding and optimal health, avoid the steroids and stimulants. Use only the protein and fatty acid supplements, but read the list of ingredients carefully because some bodybuilding protein powders include steroids (chemical names with "...androst..." or "...estran...", although trade names may be used). Newspapers frequently carry stories about athletes who were disqualified for using banned substances which they unknowingly consumed through nutritional supplements. Read the labels!

Muscular bodybuilders generally have a Waist-to-Height ratio (waist size divided by height) of less than 0.5, and their Body Mass Index is in the "overweight" category even though their total body fat is 10% or less.

Avoiding injuries. It is a law of nature that anything with moving parts, including our bodies, will eventually wear out or break down. The most common types of injuries related to exercise are sprains, muscle strains, torn ligaments, and fractures in the limbs. These injuries are frequently caused by poor technique, fatigue, structural weaknesses, or repetitive stress. Any exercise that increases the pressure of the abdominal cavity, like crunches or heavy lifting, may contribute to the formation of a hernia if there is a weakness in the abdominal walls. Overuse is the most common cause of muscle or joint injury. Exercising when something hurts just makes the injury worse. Injuries can be reduced by warming up the muscles by exercising them at a relaxed pace for a few minutes before a workout, and by allowing the body to recover for at least 48 hours after intense workouts. People who exercise vigorously on a daily basis, should stress different parts of the body. For serious injuries, seek medical attention and avoid the activity that injured you until healing occurs. During your recovery, you may want to do alternative exercises that do not stress the injured part or cause pain. Think twice before resuming an activity that injured you. Remember that the purpose of exercise is to be healthy, not to get sick. Do not exceed your limits.

Measuring the results.

One of the motivations for making exercise a part of your daily life is that you can feel and actually measure the results. Once per week, as part of your exercise program, you should weigh yourself and measure your waist. If you are physically fit, your waist size divided by your height should be less than 0.5 (Waist-to-Height ratio < 0.5). Your weight should be taken in the morning without clothes after going to the bathroom and before eating or drinking anything. Measure your waist at the navel so that the tape fits snugly but does not compress the skin. Your weight in the evening can be up to three pounds (1-1/2 Kg) heavier than your morning weight. Most of this overnight weight change is due to perspiration and excretion of bodily wastes. One cup of water weighs 1/2 pound (1/4 Kg).

Your physical measurements, the number of repetitions of your exercise program, and the ease with which you can accomplish the exercises can help you to keep track of your progress. Pictures are also useful. Take a picture once a year in a pose that highlights your muscles. In this way you will be motivated to continue your daily exercises.
Click here for my progress report and picture-taking hints.

If you have been sedentary, do not be surprised if you gain weight when you start exercising regularly. Muscle is heavier than fat. It is natural to gain weight when the fat is replaced with muscle. As long as your Waist-to-Height ratio does not change or gets smaller, your weight gain is probably due to increased muscle mass, rather than to fat buildup. Keeping track of your morning weight is also a good criterion for determining whether you need to adjust your diet to increase or decrease the number of Calories that you consume per day.

Calories Burned in 10 Minutes of Activity
Activity Body Weight
 125 - 174 
pounds
 175 - 250 
pounds
 Sleeping or sitting passively 10 14
 Standing 12 16
 Walking Downstairs 56 78
 Walking Upstairs 146 202
 Walking at 2 miles per hour 29 40
 Walking at 4 miles per hour 52 72
 Running at 5.5 miles per hour  90 125
 Running at 7 miles per hour 118 164
 Running at 12 miles per hour 164 228
 Cycling at 5.5 miles per hour 42 58
 Cycling at 13 miles per hour 89 124
 Light Gardening 30 42
 Mowing Grass 34 47
 Light Office Work 25 34
 Typing 19 27
 Chopping Wood 60 84
 Baseball 39 54
 Basketball 58 82
 Dancing 35 48
 Football 69 96
 Golfing 33 48
 Swimming 40 56
 Tennis 56 80
 Volleyball 43 65

NUTRITION     WEIGHT CONTROL


When evaluating diet advertisements, keep in mind that the Federal Trade Commission has determined that any product claims are false if they state that you can lose more than two pounds per week for more than four weeks without diet and exercise.



References:
  1. Andersen LB, Schnohr P, Schroll M, Hein HO, All-cause mortality associated with physical activity during leisure time, work, sports, and cycling to work, Arch Intern Med. 2000 Jun 12;160(11):1621-8. CONCLUSIONS: Leisure time physical activity was inversely associated with all-cause mortality in both men and women in all age groups. Benefit was found from moderate leisure time physical activity, with further benefit from sports activity and bicycling as transportation. PMID: 10847255
  2. Borghouts LB, Keizer HA, Exercise and insulin sensitivity: a review., Int J Sports Med. 2000 Jan;21(1):1-12. PMID: 10683091
  3. Baby Boomer Sports Injuries, U.S. Consumer Product Safety Comission, April 2000. [PDF]
  4. Oscar H. Franco, et al., Effects of Physical Activity on Life Expectancy With Cardiovascular Disease, Arch Intern Med. 2005;165:2355-2360.
    RESULTS: Moderate and high physical activity levels led to 1.3 and 3.7 years more in total life expectancy and 1.1 and 3.2 more years lived without cardiovascular disease, respectively, for men aged 50 years or older compared with those who maintained a low physical activity level. For women the differences were 1.5 and 3.5 years in total life expectancy and 1.3 and 3.3 more years lived free of cardiovascular disease, respectively.
  5. Petersen AM, Pedersen BK, The anti-inflammatory effect of exercise, J Appl Physiol. 2005 Apr;98(4):1154-62. PMID: 15772055. ABSTRACT: Regular exercise offers protection against all-cause mortality, primarily by protection against cardiovascular disease and Type 2 diabetes mellitus. The latter disorders have been associated with chronic low-grade systemic inflammation reflected by a two- to threefold elevated level of several cytokines.
  6. Villareal DT, Fontana L, Weiss EP, Racette SB, Steger-May K, Schechtman KB, Klein S, Holloszy JO. Bone mineral density response to caloric restriction-induced weight loss or exercise-induced weight loss: a randomized controlled trial. Arch Intern Med. 2006 Dec 11-25;166(22):2502-10. PMID: 17159017
    CONCLUSIONS: caloric restriction-induced weight loss, but not exercise-induced weight loss, is associated with reductions in bone mineral density at clinically important sites of fracture. These data suggest that exercise should be an important component of a weight loss program to offset adverse effects of calorie restriction on bone.
  7. Heinonen A, Kannus P, Sievanen H, Oja P, Pasanen M, Rinne M, et al. Randomised controlled trial of effect of high-impact exercise on selected risk factors for osteoporotic fractures. Lancet. 1996;348:1343-1347. PMID: 8918277 ABSTRACT: High-impact exercises that load bones with a rapidly rising force profile in versatile movements improve skeletal integrity, muscular performance, and dynamic balance in premenopausal women. If done on a regular basis, this type of exercise may help decrease the risk of osteoporotic fractures in later life.
  8. Karvonen J, Vuorimaa T. Heart rate and exercise intensity during sports activities. Practical application. Sports Med. 1988 May;5(5):303-311. PMID: 3387734
  9. Dunn AL, Trivedi MH, Kampert JB, Clark CG, Chambliss HO, Exercise treatment for depression: efficacy and dose response, Am J Prev Med. 2005 Jan;28(1):1-8. PMID: 15626549
    CONCLUSIONS: Aerobic exercise at a dose consistent with public health recommendations (17.5-kcal/kg/week) is an effective treatment for major depressive disorder (MDD) of mild to moderate severity. A lower dose is comparable to placebo effect.

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