This is an invited research digest contributed by Dr. N. Harasawa of RIKEN Brain Science Institute, Japan.
Are you satisfied with your physical and mental condition? The U.S. Department of Health and Human Services reports 34% of U.S. adults meet criteria of metabolic syndrome . National Institute of Mental Health reports 18% of U.S. adults have experienced a mental illness .
Metabolic syndrome is one of the risk factors for type 2 diabetes and cardiovascular disease . Furthermore, mental health is an important factor in your daily life, because mental health problems affect your behavior and physical health .
Drug treatment is one solution for metabolic syndrome and mental health problems. Physical exercise, including sports, is another that helps control your weight and improve overall mental health .
Among the many forms of exercise, swimming is one of the most preferable choices. It is easy to start for children and elder person. In the following section, I introduce four benefits of swimming, which I hope will help when you start exercising.
1. Efficient in losing weight
The U.S. Centers for Disease control and Prevention (CDC) recommends that adults obtain at least 30 minutes of moderate-intensity physical activity 5 days a week, for a total of at least 150 minutes a week . Perhaps, it is tough to make time to exercise. To make your time effective, you have to choose an efficient activity for consuming calories. CDC has estimated the amount of calories burned doing several activities, as shown in Table 1 .
You can see calories for running and bicycling are high. But please be reminded that running in 5 mph and bicycling over 10 mph is very fast and hard. In contrast, swimming in slow free style is much easier and still consumes high levels of calories: the consumption of calories by swimming is slightly lower than running and bicycling, but higher than aerobics, walking, basketball, and so on.
2. Low risk of injury
Physical activity risks injury and vigorousness increases that risk. Dr. Sheu and colleagues at CDC reported injury risk for various sports . They obtained 8.6 million sports- and recreation-related injury episodes from the 2011-2014 National Health Interview Survey and estimated the injury rate for each sport (see Table 2).
This risk indicates how frequently injury (i.e. bone fracture, muscle strain, bruises) occurred in each sport per 1,000 persons on the average. Of note, the risk of swimming, which is categorized as “water sport”, is lower compared to other vigorous sports such as basketball, football, and bicycling.
3. Boost your optimism and self-confidence
When you feel bad, swimming is one of the most effective sports to cheer you up. A Romanian research group investigated the influence of swimming on subjects’ optimism and self-confidence . Subjects joined an aquatic exercise program three times a week, for four months. Before and after this program, they answered questions evaluating their levels of optimism and self-confidence.
The higher the total score of their answers, the more optimistic they were and the more confidence they had in themselves. It was found that after the program, subjects reported higher scores, indicating subjects became more optimistic after four months of swimming.
4. Live longer
Physical activity reduces the risk of many diseases such as heart disease, cancer, type 2 diabetes, high blood pressure, osteoporosis, and obesity . Dr. Chase and colleagues in the University of South Carolina reported swimming appears to be a healthful alternative to other physical activity .
They collected data of 40,547 men aged 20-90 years who completed a health examination during 1971-2003. After adjustment for several confounding factors such as age, BMI, smoking status, alcohol intake and family history of cardiovascular disease, men who were swimmers had 53%, 50%, and 49% lower all-cause mortality risk than men who were sedentary, walkers or runners respectively. It is not clear why the mortality rate was lower in swimmers than in walkers and runners. However, the results do suggest that swimming is the preferable exercise when it comes to help living longer.
As I have shown above, you can make your body healthy, both physically and psychologically, by swimming. Swimming is one of the most recommended activities that leads to decreased body weight, and has a low risk of injury. You can also boost your optimism and self-confidence with swimming. Furthermore, you can reduce your mortality risk.
In conclusion, swimming is a great activity. A wide range of facilities and activities are available for everyone, whatever your age and ability. So if you want to be happy and healthy, please start swimming!
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