Why 30 minutes a day for at least 5 days a week was chosen for adults 18 and over?

There is a wealth of scientific evidence that as little as 30 minutes of moderate physical activity (equal in intensity to brisk walking) done on most, if not all, days of the week has substantial benefits to health (Pate 1995; SGR 1996). The President’s Council on Physical Fitness and Sports, the Surgeon General’s Office, the Centers for Disease Control and Prevention (CDC), the American Heart Association, and the American College of Sports Medicine are only a few of the many groups who have endorsed the 30-minute guideline. The thirty-minute standard was chosen because, if done regularly, it will result in significant reduction in risk of chronic disease incidence (e.g., heart disease, cancer, stroke, high blood pressure, diabetes). Also, 30 minutes of moderate activity is an amount that is reasonable for people who have not been regularly active. Five days a week was chosen as an acceptable amount even though daily activity is recommended. This allows people who may miss activity one or two days a week, but who are doing more than they normally do, to have a chance to earn the award.

Why do I have to do my activity in time blocks of 5 minutes or more?

Research (SGR 1996) has shown that benefits to health are best if your 30 minutes of activity is done in time blocks of 10 minutes or more. Because the goal of Active Lifestyle Program is to promote activity, time blocks of five minutes or more were chosen. This encourages people to add activity to their normal daily routine. Whenever possible, you are encouraged to try to do your activities for periods of 10 minutes or more. But if you park farther away in the parking lot so you can take a walk, even if it takes only five minutes, it will count.

Why was six weeks chosen for the program?

The health benefits of physical activity are realized through regular participation. Consequently, the goal is to be active throughout your lifetime. Six weeks was chosen to “get you started” and to encourage you to become a lifelong exerciser. You are allowed to accumulate your six weeks of activity over an eight-week period because factors out of your control may hinder your compliance. Ideally, your activity would be accumulated in a six-week period, but if an obstacle limits your activity for a short period of time you need not give up. You have eight weeks to accumulate your six weeks of activity.

Is 30 minutes daily really enough activity?

There is little doubt that more than 30 minutes of physical activity provides additional health benefits (SGR 1996; Pate 1995). Increasing the duration of moderate activity beyond 30 minutes can provide additional reductions in risks for chronic diseases and can be of extra value in controlling body fatness (IOM 2002; Saris, et al. 2003; Erlichman, et al. 2002; ACSM Position Stand on Weight 2001). There is little doubt that performing regular vigorous activity in addition to moderate activity has added benefits (Pate 1995; ACSM Position Stand 1998). The PALA is intended for people who are not regularly active so the national standard of 30 minutes of moderate activity was chosen. As you gradually increase your activity over time (performing activity above 30 minutes a day), including some vigorous activity is encouraged. Prior to dramatically changing your activity patterns, especially if you plan to do more vigorous activity on a regular basis, it would be wise to make sure your medical doctor confirms you are medically ready to participate.

Why was 60 minutes a day for at least 5 days a week chosen for youth less than 18 years of age?

The National Association for Sports and Physical Activity established a
standard of 60 minutes and up to several hours a day of moderate to vigorous
physical activity for youth ages 5-12 (NASPE 2004). More recently a panel of
experts commissioned by the Centers for Disease Control and Prevention (CDC)
reviewed the evidence and came to a similar conclusion.  They recommended
that school-aged youth ".... participate daily in 60 or more minutes of
moderate to vigorous physical activity that is developmentally appropriate,
enjoyable, and involves a variety of activities" (Strong et al., 2005). The
60-minute standard is also consistent with the amount of activity
recommended for British youth (1998). The CDC panel of experts based its
recommendation on evidence related to many different health factors.  An
abbreviated list includes adiposity, type-2 diabetes, cardiovascular health
and fitness, bone health, metabolic syndrome, mental health, and asthma.
Because young people do not typically have the same incidence of chronic
diseases as adults, neither the NASPE nor the CDC standards are based solely
on disease risk. Other benefits of activity were considered such as academic
achievement, improved self-concept, altered injury potential, fitness
improvement, caloric expenditure, promotion of normal growth and
development, and learning skills that will encourage lifetime activity. The
60-minute standard is designed to encourage both moderate and vigorous
physical activity. For further information you are referred to the Physical
Activity for Children: A Statement of Guidelines for Children Ages 5-12
(NASPE 2004) and Evidence Based Physical Activity for School-Aged Youth
(Strong et al., 2005).

Why were time blocks of 5 minutes or more chosen for youth?

The physical activity guidelines for youth recommend that the minimum 60-minute of activity be accumulated in several bouts of activity of at least 15-minutes in length (NASPE 2004). This time block, that is longer than the 10-minutes recommended for adults, accounts for the fact that youth are often both moderately and vigorously active in their activity bouts and that their activity is often interspersed with brief periods of rest. However, for the Physical Activity Lifestyle Award (PALA), 5-minute activity blocks were chosen to encourage youth to do activity (either moderate or vigorous) over and above the normal amount. For example, walking to school, playing at recess, playing at lunchtime, walking home from school are all encouraged. When possible, bouts of at least 15 minutes are encouraged.

Is 60 minutes a day really enough for youth?

The NASPE Guidelines call for 60 minutes and up to several hours per day. More than 60 minutes is desirable. This award is designed primarily to promote activity among those who are not currently active, so the minimum standard was chosen. Guidelines for teens recommend both 30 minutes of moderate activity for most days of the week and vigorous activity on at least three days a week (Sallis and Patrick 1994). The 60-minute (moderate and/or vigorous activity) standard was used for both children and teens because it requires the minimum time recommended for children 5 to 12 (NASPE 2004) and it requires teens to perform more activity than adults, consistent with teen guidelines.

Why was 8,500 steps chosen for adults?

Because people have the option to choose either minutes per day in activity or steps per day, it would be desirable to have equivalent standards for the two methods of activity monitoring. The 30-minute standard is well documented, but the equivalent for steps is more elusive. There is a consistent body of evidence to suggest that sedentary adults (on average) accumulate approximately 5,000 steps per day as part of normal daily living (Tudor-Locke and Bassett 2004). Accumulating steps roughly equivalent to 30 minutes of moderate activity (walking at a brisk walk) would add 3,000 to 4,000 steps per day depending on walking speed, stride length, etc. (Tudor-Locke and Bassett 2004). So, 5,000 plus 3,500 was chosen as the adult standard (8,500). A 10,000 step standard has received considerable attention in the popular media but may be too much to expect of a beginner trying to earn the PALA. Just as accumulating activity over and above 30 minutes a day has additional benefits, so does accumulating additional steps. The goal of the PALA is to get sedentary people moving so the more realistic 8,500 step count was chosen.

Why were 11,000 and 13,000 steps per day chosen for youth?

As noted in previous sections, the activity standards for youth are greater than those for adults. Research has consistently shown that youth are more active than adults and that youth need more activity than adults. Youth baseline step counts are considerably higher than for adults (NASPE 2004; Vincent, et al. 2003) so a higher step count is appropriate for young people. Studies indicate that average step counts are about 12,000 per day for youth. While there is variation across grade levels, 11,000 steps for girls and 13,000 steps for boys are typical average step counts (LeMasurier, et al. in press). The 11,000 step count for girls and 13,000 step count for boys were chosen to encourage activity levels that were attainable by beginners but that would be at least roughly equivalent to the standards for minutes in physical activity.

Why are the standards different for boys and girls?

The standard for minutes for boys and girls is the same (60), but the standard for steps is greater for boys than girls. There is evidence that boys accumulate more minutes in activity than girls, but the difference in minutes is not great (Grunbaum, et al. 2004). The 60-minute standard seems attainable for both boys and girls. The studies done to date show that girls accumulate step counts that are approximately 2,000 steps per day less than for boys (LeMasurier, et al. in press). The goal of PALA is to encourage people, especially those who are currently not active, to become more active. More girls are sedentary than boys so setting the standard too high (12,000 or 13,000) could be discouraging for them. Thus the average value for girls was chosen to encourage more girls to participate in PALA and to earn the award. The average value for both girls and boys (as reported in the current literature) was also chosen to allow inactive youth to achieve the standard, but to be challenging as well.

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