Just over 2 days into Apollo 13’s mission to the moon, there was a loud bang caused by an oxygen tank explosion. The loss of this oxygen tank caused several problems and led to the famous line by astronaut Jack Swigert, “Houston, we've had a problem.” As health and fitness professionals, it is time to realize that we too have a problem: a largely sedentary and inactive population. A lack of physical activity has a negative effect on the body similar to how the loss of the oxygen tank affected the Apollo 13 spacecraft. For example, physical activity helps individuals feel more energized (1), much like oxygen was used to power the Apollo spacecraft. However, unlike the Apollo 13 mission that experienced a sudden drop in oxygen levels, the decline in physical activity has occurred gradually over many years and is due to many different factors. Reversing these trends and promoting physical activity will therefore require creative problem solving from numerous individuals of different backgrounds, just like those in Houston who helped the Apollo 13 astronauts get back home safely.
THE (PHYSICAL ACTIVITY) PROBLEM
Daily physical activity can be separated into two categories: exercise and lifestyle. Exercise/leisure-time physical activity is defined as planned physical activity typically performed at a moderate to vigorous intensity and consists of activities such as jogging, lifting weights, and team sports. This exercise category has long been the focus of health and fitness professionals. The lifestyle physical activity category includes all of the physical activity associated with daily life such as performing occupational work tasks, household chores, and transport (2). Lifestyle physical activity is performed at a variety of intensities from light to vigorous. The physical activity accumulated from these two categories is associated with decreased mortality risk, decreased risk of developing cardiovascular disease, and even decreased risk of developing some forms of cancer (1). Regardless of whether it is performed at a vigorous-, moderate-, or light-intensity, physical activity is associated with several other health benefits, including improvements in weight management, glucose and lipid metabolism, and quality of life (1). Despite these well-known benefits of physical activity though, there has still been a gradual decline in overall daily physical activity levels. This decline is largely due to decreases within the lifestyle physical activity category.
Despite these well-known benefits of physical activity though, there has still been a gradual decline in overall daily physical activity levels.
Substantial amounts of time are spent at the workplace. As such, the workplace has traditionally been a significant contributor to lifestyle physical activity levels. However, the workplace has changed with occupational changes. For example, the percentage of workers in agricultural occupations has decreased from 12% in 1950 to less than 2% in the year 2000 (3). Manufacturing occupations within the private sector also have decreased from employing over 30% of the population in 1960 to only 12% in 2008 (4). In place of these agricultural and goods-producing occupations, there has been an increase in service occupations (i.e., professional services, health/education, and hospitality). Although 20% of workers in 1960 were employed in service occupations, by the year 2008, the number had more than doubled to 43% (4).
Occupational changes have led to changes in the physical activity performed at the workplace. In 1950, a greater percentage of individuals were employed in occupations that required high levels of physical activity compared with those requiring only low levels of physical activity. By the year 2000, this trend was reversed with the number of low physical activity occupations double that of those requiring high amounts of physical activity (3). Overall, the percentage of jobs requiring moderate-intensity physical activity has decreased from 48% in 1960 to 20% in 2008 (4). Although some evidence suggests workplace physical activity may not reduce risk of cardiovascular disease (5), others have suggested decreases in workplace physical activity may at least partly explain the increasing rates of obesity (4).
In addition to changes within the workplace, there also have been significant changes to the lifestyle physical activity associated with transportation. Since the 1960s, the proportion of trips taken by private automobile have become greater while the prevalence of active transportation (walking or cycling) has decreased (3). This trend is especially evident with regard to commuting to work. In 1960, 67% of adults commuted to work via car, whereas in the year 2000, the number was 88% (3). Also worrisome is the daily miles traveled by vehicle, which has steadily increased since 1950 (3). Adults now drive an average of 29 miles per day and spend an average of 55 minutes per day in cars (3). These substantial amounts of time spent in the car have replaced physically active forms of transportation and are associated with a greater risk for obesity (6).
Changes in transportation are not limited to adults. A decrease in physically active transport also have been observed for children. In 1969, nearly 50% of elementary school children walked or rode a bicycle to school, but by 2009, the number decreased to 13% (7). Even outside of traveling to school, many children and adolescents do not travel in a physically active manner. Currently, 62% of children and adolescents 12 to 19 years old do not report performing any form of active transportation in a week (8). Some of the reasons for the decreased levels of active transportation are increased urban sprawl, traffic safety concerns, and safety from child predators. Only 57% of households with children younger than 13 years reported having a public school within 1 mile of their house (3). The greater travel distances children and adolescents now face reduces the potential to travel in a physically active manner (8). The result is a greater reliance on automobiles to get to various destinations, representing another missed opportunity to include physical activity in the regular day.
Reductions in lifestyle physical activity levels also have occurred due to changes within the home. Various devices/appliances have been invented that reduce the physical activity associated with performing household chores. For example, sweeping requires moderate-intensity physical activity but can now be replaced with an autonomous robotic vacuum cleaner (e.g., Roomba® vacuums). Other examples of labor-saving inventions include dishwashers, clothes washers and dryers, microwaves, and even disposable plates and dishes. These inventions are not only labor saving but also time saving and have significantly decreased the time spent on household chores. Most readers are probably happy to spend less time on household chores. However, light- to moderate-intensity physical activity is beneficial for weight control as well as reducing risk for chronic disease (1), meaning reductions in these forms of physical activity are problematic.
Various devices/appliances have been invented that reduce the physical activity associated with performing household chores. For example, sweeping requires moderate-intensity physical activity but can now be replaced with an autonomous robotic vacuum cleaner (e.g., the "Roomba").
Although the time spent on chores has decreased, there has been an increase in sedentary screen time. In 1950, only 10% of households had a television. By 2005, 98% of households had at least one television (3). With an increase in the number of televisions, there also has been an increase in time spent watching television. Since 1950, time spent watching television has increased roughly 1% each year (3). U.S. adults now watch an average of 2.8 hours per day, which accounts for over half of all leisure-time activities (9). An additional 0.5 hours per day is spent on a computer or playing games for leisure (9). Children and adolescents also have experienced drastic increases in screen time as a growing number have personal computers and/or cell phones. Since 2003, the percentage of high school students reporting they spend more than 3 hours per day on the computer or other screens has nearly doubled to 43% (10).
Although lifestyle physical activity has decreased over the years, the percentage of adults participating in exercise/leisure-time physical activity has actually increased (3,11) with one study showing a 2% increase from 1990 to 2000 (3). The widespread promotion of exercise as a tool to prevent chronic disease has contributed to these increasing levels. Current levels are still problematic though and contribute to the inadequate levels of daily physical activity. In the latest Centers for Disease Control and Prevention report (12), only 52% of adults met the minimum recommendation of 150 minutes per week of moderate-intensity physical activity and only 32% of adults met the higher recommendation of 300 minutes per week. With regard to muscle strengthening guidelines, only 29% of adults met the recommendation of performing two or more strengthening routines per week. The percentage of adults meeting both the aerobic and strength recommendations is even lower, with only 21% of U.S. adults meeting the guidelines (12). Age plays a significant role in whether individuals meet recommendations as the percentage of adults meeting recommendations decreases with age. A greater percentage of adults 18 to 44 years old met both aerobic and muscle strengthening recommendations (28%), compared with those 45 to 64 years (19%) and those over 65 years (13%) (12). This is especially problematic because regular exercise is important for decreasing the risk of chronic diseases that often occur in older individuals (1).
Similar to adults, the percentage of children and adolescents currently meeting physical activity recommendations is low. For children 6 to 11 years old, only 43% currently meet recommendations. The percentage drops dramatically for those 12 to 15 years old (8%) and remains low for those 16 to 19 years old (5%) (8). Conflicting trends have led to these low percentages. Since the 1970s, participation in team sports has remained fairly constant for boys, whereas participation for girls has actually increased after the implementation of Title IX (13). However, participation is still low as only an approximate 55% of children and adolescents report participating in some form of team sport within the last year (8). Even lower is the percentage of children and adolescents participating in a school physical education class (30% in 2017), which has not changed over the past 2 decades (10). By contrast, the time spent in unstructured outdoor play has decreased. In 1997, 16% of children 6 to 12 years old spent time outdoors compared with only 10% in 2003 (8).
The declines in daily levels of physical activity have been gradual, and thus it is difficult to fathom just how much they have decreased. However, the cumulative effect of numerous small changes has resulted in a large overall decline in daily physical activity. This is best illustrated by comparing modern society with a more traditional agrarian society. The Old Order Amish are an agrarian society in the United States and Canada who refrain from using modern technology and live in a way similar to that of the late 1800s. Much of their day is centered around farming, cutting firewood, and maintaining the household (childcare, cooking, laundry, etc.). Performing these tasks without modern technology, Amish adults accumulate an average of 48 hours per week of moderate- to vigorous-intensity physical activity (14). By contrast, adults in modern society with modern technology and numerous labor-saving devices accumulate only 2.7 hours per week of moderate- to vigorous-intensity physical activity (15). Children in these Amish societies also are more active, accumulating 30% to 50% more daily steps than children in modern society (16).
Performing these tasks without modern technology, Amish adults accumulate an average of 48 hours per week of moderate- to vigorous-intensity physical activity.
A SITUATION REQUIRING INGENUITY
The oxygen tank on the Apollo 13 spacecraft exploded with a bang and created a situation that required a considerable amount of creative problem solving. The Apollo 13 mission brought to life the popular idiom of fitting a square peg into a round hole as they had to determine how to remove carbon dioxide from the spacecraft using a square canister and cylindrical socket. Although the current problems with physical activity have developed more gradually, modern society is faced with a similarly difficult task. Modern technologies have strived to improve quality of life by decreasing physical activity, and there is now a need to increase physical activity to improve health. Finding innovative ways to reintroduce lifestyle physical activity into daily life will be important for reversing trends. In addition, a continued push is needed to increase the proportion of the population meeting exercise recommendations. Health and fitness professionals will play an integral role in bringing about these changes.
Numerous publications, campaigns, and programs involving health and fitness professionals have contributed to increasing the percentage of adults participating in exercise/leisure-time physical activity (11). Key components of these programs have been educating the public about the benefits of exercise, creating environments that promote physical activity, and creating physical activity recommendations. This type of concerted effort is now needed for promoting and increasing physical activity within the lifestyle category. A primary aim of these campaigns and programs should be to change the current culture that promotes physical inactivity. An example is presently underway in Australia, which is targeting workplace sitting. The project involves a free online toolkit (BeUpstanding.com.au) with the information and resources required to help reduce sitting and increase physical activity in the workplace. One of the fundamental components of this toolkit is employer and employee participation, which is designed to increase support and ownership of the program and therefore change the existing workplace culture. This type of program is also needed outside of the workplace and should be the focus of future campaigns and programs to further increase levels of daily physical activity.
Novel technologies represent another way to increase physical activity. The recent development of e-bikes is one example of using technology to promote active transportation. E-bikes, specifically pedal assist e-bikes, have an electric motor that provides assistance while pedaling, thereby reducing the physical-intensity level associated with cycling. Although the motor of an e-bike reduces the intensity, it also helps to overcome many of the barriers to cycling as a mode of active transportation (e.g., fitness limitations, work hygiene concerns, and long commuting distances). As a result, e-bikes can increase physical activity by providing a suitable replacement for car trips and making cycling a more enjoyable mode of exercise. The use of e-bikes can still be limited by traffic safety concerns though, highlighting the need for policy and environmental changes to further promote active transport.
Online toolkits and novel technology are just two examples of the many different ways to increase daily physical activity levels. Several other strategies are also needed to address the ways in which physical activity has decreased in daily life, and these are discussed within this issue. In addition to increasing physical activity at the workplace and during transportation, other strategies will need to target leisure-time physical activity as well as increase the percentage of the population participating in exercise. Furthermore, innovative thinking is needed to increase physical activity across the age range from birth through old age. Although this work to increase physical activity may seem daunting, the challenge is no greater than those faced by the Apollo 13 mission. Thus, continued hard work from a variety of individuals, including health and fitness professionals, can give this story a similar happy ending.
BRIDGING THE GAP
Although exercising levels have increased slightly, lifestyle physical activity has decreased at the workplace, school, home, and during transportation. These changes have resulted in historically low levels of overall physical activity. To reverse these trends, innovative strategies from health and fitness professionals are needed to promote both lifestyle physical activity and exercise.
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Keywords:© 2019 American College of Sports Medicine.
Sedentary; Workplace; Active Transportation; Lifestyle; Health Surveys