OBESITY & EXERCISE
Written by Slawomir (“Swavak”) Gromadzki, MPH
Regular physical activity is one of the most effective ways of attaining a negative energy balance. It should be undertaken in accordance with your overall health and mobility.
Anyone suffering from coronary heart disease, hypertension, and physical impairment, such as severe osteoarthritis or extreme obesity, should consult a healthcare practitioner before starting an exercise routine.
It has been shown that one of the causes of obesity is the variation of the so called obesity gene which may increase the risk of obesity by over 20%. However, the good news is that according to the 2011 study even moderate physical activity such as walking is able to reduce the negative influence of this obesity-related gene variation by more than 25%!
A 2012 study by Prof. Qibin Qi demonstrated that, “a sedentary lifestyle marked by watching television four hours a day increased the genetic influence by 50 percent.” On the other hand, “a brisk one-hour daily walk reduced the genetic influence towards obesity, measured by differences in BMI by half.”
In addition, it is a well-known fact that exercise greatly improves mood and metabolism, and according to Professor McArdle, energetic physical activity keep on improving the metabolic rate even for up to 15 hours after the exercise is finished! Also the 2011 study by a group of scientists from North Carolina Research Campus demonstrated that, “A 45-minute vigorous exercise bout increases metabolic rate for 14 hours.”
Increased physical activity reduces appetite at least in the short term by increasing the body’s sensitivity to hormones that control appetite. It may also protect against the insulin resistance associated with obesity. Everybody knows that exercise burns calories and improves metabolism, but it has other very important benefits. One of them is the ability to improve insulin sensitivity in our skeletal muscles which lowers insulin levels in the blood thus reducing our appetite especially in between meals.
Physical activity helps to control stress and, therefore, reduces stress-induced eating. According to the 2012 study by Prof. Gary S. Goldfield and his colleges exercise boosts obese teens’ mental health. Overweight or obese adolescents who were engaged in aerobic exercise tend to feel better about themselves, even in the absence of weight loss. He also stated that, “Improved aerobic fitness from the exercise was a much better predictor of psychosocial benefits than weight loss or reductions in body fat… Throw away the scale and get out there and start moving, and the activity can improve your emotional well-being even if it does not lead to any measurable change in weight or body fat.”
As far as exercise is concerned fast walking outside seems to be the best type of exercise. If the weather is bad exercise at home. You can use exercise bike, mate, treadmill, Xbox Kinect games, etc. But please remember that aerobic exercises (outside in the open air) are the best. You need a minimum of 30 to 60 minutes of physical activity four to five times a week. Recently I’ve read the following testimony by ‘Nayo’ which should encourage you to walk and improve your diet: “My boss lost 40 pounds in just months, by walking 5 times a week 4 miles a day. He said he just changed his diet and walked”.
Although jogging burns 30 to 40 % more calories than brisk walking, yet walking should be more effective than jogging or running because it burns more fat. Strenuous exercise such as running requires fast type of energy (which is sugar) thus stimulating your body to burn more sugar than fat. Apart from that, walking is safer for your heart and it greatly reduces the risk of injury. Runners are about 15 times more likely to be hurt than walkers. The Mayo Clinic health professionals say that brisk walking is the best type of exercise which leads to a “higher level of health” and other numerous benefits. It is effective in burning calories, strengthens your immune system, manages stress, lower blood cholesterol, and helps you to stay strong and active by increasing energy levels. In addition to that, energetic exercise such as fast walking regulates blood pressure, reduces risk of stroke and heart attack, and lowers the risk of diabetes.
If you still prefer to run instead of walk make sure it is just a gentle jogging, Always start with walking and slowly increase the speed, then switch to gentle jogging and end up with walking again. Remember that if you exercise too hard you will trigger stress reaction in your body thus releasing stress hormones which weaken your immune system making you more prone to diseases. That’s why it was shown that strenuous physical activity makes people five or six times more likely to catch the flu! Also Dr. Dean Ornish recommends brisk walking over jogging, suggesting that some people are seven times more likely to die while jogging.
You must be very careful with any form of physical activity if you suffer from Coronary Heart Disease (CHD) or any other condition involving heart muscle. Although research show that individuals with CHD who exercise appropriately have very low risk of experiencing heart attack or death while exercising (only one heart attack for every 300,000 hours, and one death for every 800,000 hours of exercise), yet it is still wise to consult your physician before you start to exercise on a regular basis. Walking at a brisk pace for at least 30 minutes a day will promote heart health but you should start with slow walking and every day increase the pace and the duration of walking a little bit. Never exceed your safe heart-rate speed. If possible and recommended in your case, try to exercise with a friend and always carry a mobile phone. If prescribed, remember to have nitroglycerine while exercising. If you are able to keep on talking while exercising it means that for you the exercise is of a moderate intensity, but if you are not able to talk, it would mean you are exercising vigorously.
Here is the information concerning the amount of energy (in calories per minute) you should use for different activities: Sleep 1.0, Lying 1.5, Sitting 1.6, Standing 1.9, Ironing 3.0 – 4.0, Walking (2 mph) 3.2, Walking (3.5 mph) 4.5, Cycling 4.5-7.0, Stair climbing 7.5, Tennis 7.0, Swimming 5.0-10.0.
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