Researchers from the University of California, San Diego, have found that people over 65 watch three times more TV than younger adults.
Watching six hours or more of TV per day could shorten the average life expectancy by nearly five years, a recent Australian study suggests. Researchers say it's the first study to look at the loss of life associated with this sedentary activity.
"TV viewing time may have adverse health consequences that rival those of lack of physical activity, obesity and smoking," write researcher J. Lennert Veerman, of the University of Queensland, Australia, and colleagues in the British Journal of Sports Medicine. "Every single hour of TV viewed may shorten life by as much as 22 minutes."
Previous studies have already linked sedentary behavior with a higher risk of death, especially from heart attack or stroke. Watching TV is known to account for a large amount of sedentary activity. But researchers say until now its impact on life expectancy has not been measured independently.
TV Watching and Life Expectancy
In the study, researchers used a combination of survey data starting in 1999-2000 until 2008 and death figures for Australia to calculate life expectancies associated with TV watching. The people in the survey answered questions about how much time they had spent in the previous week watching TV or videos.
Based on the results, researchers estimated that Australian adults aged 25 and older watched 9.8 billion hours of TV. Every single hour of television watched after age 25 was associated with a 22-minute reduction in average life expectancy.
Researchers say their calculations show that an adult who spends an average of six hours per day watching TV can expect to live 4.8 years fewer than someone who does not watch TV.
In comparison, previous research has shown that lifelong smoking is associated with a four-year reduction in life expectancy after age 50. The average loss of life from one cigarette is estimated to be 11 minutes, or the equivalent of watching half an hour of TV, according to this study.
Other Health Risks
In the study published in 2011, in the Journal of the American Medical Association, researchers combined data from eight such researches and found that for every additional two hours people spend glued to the tube on a typical day, their risk of developing type 2 diabetes increases by 20% and their risk of heart disease increases by 15%. And, for every additional three hours, the study participants spent in front of the TV, their risk of dying from any cause during the respective studies jumped 13%, on average.
"When put together, the findings are remarkably consistent across different studies and different populations," says Frank Hu, M.D., a professor of nutrition and epidemiology at the Harvard School of Public Health, in Boston, Massachusetts, who coauthored the analysis.
The increased risk of disease tied to TV watching "is similar to what you see with high cholesterol or blood pressure or smoking," says Stephen Kopecky, M.D., a cardiologist and professor of medicine at the Mayo Clinic in Rochester, Minnesota, who was not involved in the research. The new analysis, he adds, "elevates the importance of the sedentary lifestyle" as a risk factor.
The connection between TV and disease isn't a mystery. TV watching eats up leisure time that could be spent walking, exercising, or even just moving around, and it has also been linked to unhealthy diets, including consuming too much sugar, soda, processed food, and snacks -- foods, perhaps not coincidentally, that are often found in television commercials.
What's more, some studies suggest that prolonged sitting, over and above its impact on eating habits and exercise, may cause metabolism changes that contribute to unhealthy cholesterol levels and obesity.
"This is really the couch-potato syndrome," Hu says. "These are extremely sedentary people who spend several hours on a couch watching TV. They're very passive and their energy expenditure is very low, even compared to other sedentary behaviors like sitting and reading, or sitting while driving."
Studies conducted by the Stanford University of Medicine prove that TV viewing is directly linked with mindless eating. You have more chances of eating junk foods while watching TV than in any other activity! It really feels very nice to enjoy burgers, pizzas and French Fries while watching your favorite shows.
The light emitted from the television can prove to be too stimulating to our systems. This can reduce the levels of the brain hormone melatonin, which usually increase in the evening as light levels fall. This may affect the body's natural rhythm, keeping you awake longer and results in irregular sleep and extreme fatigue.
Are there any Benefits?
Not all tube-watching is a big waste of time. In fact, research suggests that certain programs may actually have health benefits for you and your family.
Take nature shows, for instance: In one new study from the University of Rochester in New York, people who watched nature scenes felt more energetic and charitable. Previous studies have found that just looking at still images of nature can lower blood pressure and muscle tension, two markers of unhealthy stress.
How to Minimize the Risks?
If you sit on a couch or chair, watching TV, you can still exercise, lowering the negative consequences of the sedentary lifestyle.
1. Biceps curls (arms)
While seated, take a dumbbell in each hand, or a heavy book in each hand if you don't have weights. Flex your arms at the elbows and pull in an upward arc toward your shoulders, with the palms of your hands facing the ceiling and your elbows close to your waist. Pause for a moment to contract your biceps at the peak of the exercise. Lower and repeat the movement for 10 or more reps.
2. Hand grippers (forearms and wrists)
These little gadgets are great for strengthening your forearms and wrists, and I use them all the time for that reason. What's more, grip strength is a good overall indicator of how fit you are. In fact, clinicians have used grip strength to measure levels of fitness and performance in older adults. You simply grasp the handles in one hand and squeeze them together as closely as you can. Keep squeezing until you can't do another, then switch hands and repeat the exercise.
3. Trunk twists (side abdominals)
Sit with good posture. Bend your elbows and hold them close to the sides of your body. Slowly rotate your trunk to the right as far as you comfortably can, being sure to keep your torso stable. Rotate back to the center and repeat the move to the left. Do this 10 times, with two twists counting as one repetition.
4. Leg lifts (abdominals)
Sit with good posture toward the edge of the couch or chair. Hold on to the sides and extend your legs straight out. Lean back slightly so that your abs feel contracted and engaged. Bend your knees, bringing them in toward your chest. Repeat this move 10 or more times.
5. Leg extensions (front thighs)
Attach some ankle weights to each ankle. Sit toward the edge of the couch or chair. Hold on to the sides. Bend your knees. Then lift your lower legs up to a straight, locked-knee position. Lower and repeat 10 or more times. Do this move slowly, using about 2 to 3 seconds each to lift and lower your legs.
6. Toe lifts (calves)
Sit with good posture toward the edge of the couch or chair, with your knees bent and your feet flat on the floor. Lift your heels up off the floor as high as you can, up on the balls of your feet. Hold for 2 seconds, then lower. Repeat 10 or more times. You can make this exercise more intense by placing a heavy book across the top of your thighs and lifting and lowering your heels with the book in place.
No, these exercises will never replace fitness in the gym, however, they will help you to burn some calories and flex your muscles.
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