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8
Revisiting ‘‘How Many Steps Are Enough?’’
CATRINE TUDOR-LOCKE
1
, YOSHIRO HATANO
3
, ROBERT P. PANGRAZI
2
, and MINSOO KANG
4
1
Walking Behavior Laboratory, Pennington Biomedical Research Center, Baton Rogue, LA;
2
Physical Education, Arizona
State University, Mesa, AZ;
3
Kyushu University of Health and Welfare, Kyushu, JAPAN; and
4
Department of Health and
Human Performance, Middle Tennessee State University, Murfreesboro, TN
ABSTRACT
TUDOR-LOCKE, C., Y. HATANO, R. P. PANGRAZI, and M. KANG. Revisiting ‘‘How Many Steps Are Enough?’’ Med. Sci. Sports
Exerc., Vol. 40, No. 7S, pp. S537–S543, 2008. With continued widespread acceptance of pedometers by both researchers and
practitioners, evidence-based steps/day indices are needed to facilitate measurement and motivation applications of physical activity
(PA) in public health. Therefore, the purpose of this article is to reprise, update, and extend the current understanding of dose–response
relationships in terms of pedometer-determined PA. Any pedometer-based PA guideline presumes an accurate and standardized
measure of steps; at this time, industry standards establishing quality control of instrumentation is limited to Japan where public health
pedometer applications and the 10,000 stepsId
j1
slogan are traceable to the 1960s. Adult public health guidelines promote Q30 min of
at least moderate-intensity daily PA, and this translates to 3000–4000 steps if they are: 1) at least moderate intensity (i.e., Q100
stepsImin
j1
); 2) accumulated in at least 10-min bouts; and 3) taken over and above some minimal level of PA (i.e., number of daily
steps) below which individuals might be classified as sedentary. A zone-based hierarchy is useful for both measurement and motivation
purposes in adults: 1) G5000 stepsId
j1
(sedentary); 2) 5000–7499 stepsId
j1
(low active); 3) 7500–9999 stepsId
j1
(somewhat active);
4) Q10,000–12,499 stepsId
j1
(active); and 5) Q12,500 stepsId
j1
(highly active). Evidence to support youth-specific cutoff points
is emerging. Criterion-referenced approaches based on selected health outcomes present the potential for advancing evidence-based
steps/day standards in both adults and children from a measurement perspective. A tradeoff that needs to be acknowledged and
considered is the impact on motivation when evidence-based cutoff points are interpreted by individuals as unattainable goals.
Key Words: PEDOMETER, CRITERION-REFERENCED, NORM-REFERENCED
Defining and promoting precise dose–response rela-
tionships in terms of physical activity (PA) and
health are among the most important public health
pursuits in this era of increasing obesity rates. Traditionally,
health-related PA recommendations have focused on multi-
ple elements of frequency, intensity, duration, and mode of
PA; widely accepted adult public health guidelines promote
Q30 min of at least moderate-intensity daily aerobic PA,
such as brisk walking (47). This PA can be accumulated in
brief bouts (i.e., minimally 10 min in duration) during the
course of a day (24,53).
The ability to track daily accumulated PA has recently
improved with the advent of body-worn motion sensor
technology, including accelerometers and pedometers. Of
the two motion sensors, pedometers are generally consid-
ered the more practical (i.e., simple to use, affordable)
alternative for individual- and population-level applications
(14,37). Although pedometers are not able to discriminate
PA intensity on their own, they do provide a simple and
affordable means of tracking daily PA (especially walking)
expressed as a summary output of steps/day. In addition,
their output correlates highly with that of different acceler-
ometers (45). Because the most commonly reported PA is
walking (7,28), researchers and practitioners require steps/
day indices associated with important health-related out-
comes (e.g., obesity, hypertension, etc.) and/or health-related
levels of PA (i.e., translations of public health recommenda-
tions) in terms of walking (36). Therefore, the purpose of this
article is to reprise, update, and extend the current under-
standing of ‘‘how many steps/day are enough?’’
THE 10,000 STEPSId
j1
SLOGAN IN JAPAN
A value of 10,000 stepsId
j1
is often associated with a
healthful level of PA (8,21,34,35) and is commonly
promoted despite any authoritative endorsement; a simple
Google search of the terms ‘‘10,000 steps’’ and ‘‘pedometer’’
returns more than 113,000 hits (based on a December 27,
2005 search). This increasingly popular index can be traced
to the 1960s when Japanese walking clubs embraced a
pedometer manufacturer’s (Yamasa Corporation, Tokyo,
Japan) nickname for their product: manpo-kei (literally
translated, ‘‘ten thousand steps meter’’) (15). Subsequently,
Dr. Yoshiro Hatano studied typical steps per day of various
lifestyles and established that 10,000 stepsId
j1
translated to
approximately 300 kcalId
j1
(or 300 METsImin
j1
)foran
Address for correspondence: Catrine Tudor-Locke, Walking Behavior
Laboratory, Pennington Biomedical Research Center, 6400 Perkins Rd,
Baton Rogue, LA 70808; E-mail: Catrine.Tudor-Locke@pbrc.edu.
0195-9131/08/407S-S537/0
MEDICINE & SCIENCE IN SPORTS & EXERCISE
Ò
Copyright Ó2008 by the American College of Sports Medicine
DOI: 10.1249/MSS.0b013e31817c7133
S537
Copyright @ 200 by the American College of Sports Medicine. Unauthorized reproduction of this article is prohibited.
8
average middle-aged Japanese man (15). Dr. Hatano has
tracked habitually active walkers (i.e., intentional walking for
70 minId
j1
,7dIwk
j1
) and found that they achieve ;8500
stepsId
j1
over incidental, miscellaneous daily activities
amounting to 1000 to 3500 stepsId
j1
, for a total of 9500
to 12,000 stepsId
j1
. Regardless of the target value, the
concept of tracking pedometer-determined PA has been
given credence by the Japanese Ministry of Health and
Public Welfare. Health Nippon 21 by the Japanese Ministry
of Health and Public Welfare (public health objectives
similar to the US Healthy People 2010) set a national goal
to increase 1000 steps over the 1998 baseline values (7200
and 8200 stepsId
j1
for females and males, respectively).
The Japanese have long recognized that any discussion of
‘‘how many steps/day are enough’’ presumes an accurate
and standardized measure of steps. Japanese industry
standards have been set to regulate pedometer quality to
within 3% error of miscounting during normal walking (i.e.,
80 mImin
j1
) (15). Dr. Hatano has stated that this speed of
walking is approximately equivalent to a stepping rate of
120 stepsImin
j1
. Pedometer accuracy is typically reported
to fall off dramatically at speeds of less than 54 mImin
j1
,
where generated vertical acceleration forces are less likely
to be detected (1,13,20). In Japan, this selective ability to
detect steps taken is considered an attribute that censors
those movements unlikely to contribute to health, while
simultaneously reinforcing participation in more forceful
(i.e., higher intensity) walking. To emphasize, every step
does not count; a greater value is placed on ‘‘healthy’’ steps,
and this is reflected in instrument-sensitivity thresholds.
Unfortunately, pedometer quality is not regulated outside
Japan, and instrument accuracy can vary greatly (44). A
more thorough discussion of these issues is outside the
purview of this article.
HOW MANY STEPS ARE ENOUGH FOR
ADULTS?
Prudence dictates that any accepted steps/day guidelines
be congruent with existing PA recommendations to prevent
being perceived as just another source of confusion and
disagreement. As previously stated, adult public health
guidelines promote Q30 min of at least moderate-intensity
daily PA (46). Evidence continues to accumulate that 30 min
of minimally moderate-intensity PA translates directly to
3000–4000 steps (41,43,50,52). Furthermore, Tudor-Locke
et al. (43) have reported that a minimal stepping rate of 100
stepsImin
j1
represents the floor value (i.e., absolute minimal
value) for moderate-intensity walking in adults. It is
important to emphasize here that, to be considered equivalent
to public health guidelines, these 3000–4000 steps should be
of at least moderate intensity (i.e., be Q100 stepsImin
j1
), be
accumulated in at least 10-min bouts, and be taken over and
above some minimal level of PA (i.e., number of daily steps)
below which individuals might be classified as sedentary. As
previously suggested (36,39), total daily values less than
approximately 5000 stepsId
j1
may be an appropriate index
of sedentary activity that is associated with higher prevalence
of obesity, for example. Adding 3000–4000 steps to this
proposed sedentary activity index approximates 8000–9000
stepsId
j1
. In contrast, the 2002 Institute of Medicine (IOM)
report (16) indicated that, although some health benefits
could be attained with commonly promoted amounts and
intensities of PA, 30 min is insufficient on its own to prevent
weight gain. The IOM actually recommended double the
time (i.e., 60 min of at least moderate-intensity daily activity)
previously endorsed by the US Surgeon General (47). An
equivalent steps/day index (i.e., 5000 steps from the
proposed sedentary activity index plus twice the 30-min
steps conversion) would therefore range as high as 11,000–
13,000 stepsId
j1
.
In 2004, Tudor-Locke and Bassett (36) reviewed the
published literature and proposed preliminary pedometer-
determined PA cutoff points for healthy adults: 1) less than
5000 stepsId
j1
(sedentary); 2) 5000–7499 stepsId
j1
(low
active); 3) 7500–9999 stepsId
j1
(somewhat active); 4)
Q10,000–12,499 stepsId
j1
(active); and 5) Q12,500 step-
sId
j1
(highly active). Between the two primary anchors of
5000 stepsId
j1
(sedentary) and 10,000 stepsId
j1
(active),
they reported smoothing the categories to convenient 2500-
stepsId
j1
increments. That being said, the category des-
ignated by 7500–10,000 stepsId
j1
(described as somewhat
active) is gaining credibility as evidence continues to
accumulate that health benefits can be realized (and that
accepted public health guidelines are achievable) within this
level (18,33,40). Working independently, Dr. Hatano has
set a very similar steps/day hierarchy with additional
gradations: 1) less than 1499 stepsId
j1
(no moving); 2)
1500–3499 stepsId
j1
(sedentary); 3) 3500–4999 stepsId
j1
(somewhat sedentary); 4) 5000–7999 stepsId
j1
(moderate);
5) 8000–9999 stepsId
j1
(somewhat active); 6) 10,000–
11,999 stepsId
j1
(active); and 7) Q12,000 stepsId
j1
(special).
On a population level, specific quantitative indices (i.e.,
benchmarks or cutoff points) are required for screening,
surveillance, intervention, and program evaluation. Such
cutoff points permit us to monitor, compare, and track
population PA behavior trends. On an individual level,
echelons produced from these cutoff points can be used to
guide and evaluate behavior change. We must emphasize,
however, that any steps/day cutoff points must be inter-
preted loosely. The overlap in steps/day between sex and
age groups, the variance that has been repeatedly observed,
and the inevitable potential for misclassification dictate that
precision of these cutoff points and associated increments
should not be overstated. It is possible to lose sight of the
utility of such cutoff points in the push to illuminate the
more obvious shortfalls. We therefore advocate a ‘‘zone’’
approach to assessing and promoting pedometer-determined
PA congruent with the categories originally proposed by
Tudor-Locke and Bassett (36). For example, we can both
promote and interpret individual progress through the steps/
day zone hierarchy. From an individual intervention
http://www.acsm-msse.orgS538 Official Journal of the American College of Sports Medicine
Copyright @ 200 by the American College of Sports Medicine. Unauthorized reproduction of this article is prohibited.
8
perspective, it is important to emphasize that any derived
guidelines should be conveyed to the end-users as assistive
rather than prescriptive; any movement upward (or holding
ground at the highest echelons) should be valued as
meritorious.
HOW MANY STEPS ARE ENOUGH FOR
CHILDREN?
A paper by Vincent and Pangrazi (48) was one of the first
studies conducted that examined a large sample of students
aged 6 to 12 yr. Participants (N= 711) wore sealed pe-
dometers for four consecutive days. Pedometer-determined
PA ranged from 10,479 to 11,274 and from 12,300 to
13,989 stepsId
j1
for girls and boys, respectively. Large
individual variability existed among children of the same
sex. Statistical analysis showed no significant differences
between ages, but a significant difference between boys and
girls was found. On the basis of these data, Vincent and
Pangrazi suggested that a reasonable PA standard might be
11,000 stepsId
j1
for girls and 13,000 stepsId
j1
for boys. An
interesting finding in this study was the lack of significance
between age classifications. It has commonly been theo-
rized that youngsters become less active with age, and this
study (followed by others) has shown that there is little
decrease in PA throughout the preadolescent stage of
development.
An oft-quoted standard in recent pedometer studies with
youth is the thresholds set by the President’s Council on
Physical Fitness and Sports (PCPFS). To earn the Presi-
dential Active Lifestyle Award (27), youngsters must
average 13,000 and 11,000 stepsId
j1
for boys and girls,
respectively, over a 6-wk period. Although researchers
often quote these values as aspirational PA goals, in ac-
tuality they are based on a cross-sectional study by Vincent
and Pangrazi (48) that focused on typical PA levels, not
necessarily desirable levels. Although other studies have
shown similar levels of steps/day accumulated by children,
the PCPFS thresholds should not be regarded as criterion-
referenced health standards but rather as award boundaries
that may change if future studies offer more understanding
and insight into healthy PA levels.
US Guidelines established by the National Association for
Sport and Physical Education in 1993 (25) recommended
that elementary school children should be physically active
for at least 30–60 min daily. The UK Health Education
Authority has recommended that all young people accumu-
late at least 1 h daily of PA that is of at least moderate
intensity (4,6). The IOM 2002 report (16) included both
adults and children in its recommendation for at least 1 h
daily of PA (16) if body fat maintenance is the desired
outcome. The most recent revision of the National Associ-
ation for Sport and Physical Education recommendations
actually pushes for even more PA in youth. That is, youth
should accumulate at least 60 min and up to several hours
of moderate-to-vigorous PA (MVPA) daily (26). Although
Scruggs et al. (32) have reported that 6- to 7-yr-old
schoolchildren take approximately 1800 steps in a 30-min
physical education class specifically taught to meet a
minimal standard of achieving MVPA, a more direct
conversion of pedometer-determined PA to time-based
equivalents of MVPA in children has only recently been
published. Specifically, Jago et al. (17) recorded 117
pedometer stepsImin
j1
taken by 78 11- to 15-yr-old Boy
Scouts in timed walking bouts at a pace equivalent to 3
METs (i.e., metabolic equivalents indicative of minimally
moderate-intensity PA) or 3510 steps in a 30-min period.
Because 3 METs is a floor value of moderate-intensity PA
and health recommendations value even higher levels of
intensity, the authors were justified in adjusting and
simplifying the message to recommend 4000 steps in
30 min or at least 8000 stepsId
j1
to meet widely accepted
time-based recommendations (i.e., at least 60 min). The
overall 3000–5000 stepsId
j1
difference between this direct
conversion of minimal time in MVPA and the norm-based
daily values reported by Vincent and Pangrazi (48) likely
also captures residual steps/day derived from incidental,
miscellaneous activities of daily life. In addition, the
estimate of Jago et al. (17) captures only that PA directly
related to general health enhancement and is not focused on
questions of energy balance as reflected by a healthy body
composition.
A study by Tudor-Locke et al. (42) examined body mass
index (BMI)-referenced standards for pedometer steps/day
in preadolescent youth. This study was a secondary analysis
of pedometer data and BMI based on 1954 youth from the
United States, Australia, and Sweden. The contrasting
group method (described below) was used to identify
optimal age- and sex-specific standards for steps/day related
to international BMI cutoff points (12) for normal-weight
and overweight/obese children. In this study, the optimal
cutoff point that separated normal-weight and overweight/
obese students was 12,000 stepsId
j1
for girls and 15,000
stepsId
j1
for boys. In other words, students averaging fewer
daily steps than this cutoff point were more likely to be
labeled as overweight/obese. Mean differences between
normal-weight and overweight/obese boys and girls were as
large as 5000 stepsId
j1
. Although this study is an example
of a criterion-referenced approach to setting pedometer-
determined PA, it is important to emphasize that this is still
based on cross-sectional data and, as such, is of limited use
in inferring causality.
It is important to emphasize here that, if these apparently
higher steps per day cutoff points are to be touted as PA
recommendations, they should come with the caveat that, at
least according to the recent work of Jago et al. (17),
minimally 8000 of these steps (representing 67% of daily
steps for girls, although no girl-specific step conversion is
yet available, and 53% for boys) should be performed at no
less than moderate to vigorous intensity. Rowlands and
Eston (30) recently reported that, in a small sample (N= 34)
of children, all those who met the Tudor-Locke et al. (42)
HOW MANY STEPS ARE ENOUGH? Medicine & Science in Sports & Exercise
d
S539
Copyright @ 200 by the American College of Sports Medicine. Unauthorized reproduction of this article is prohibited.
8
BMI-referenced cutoff points also accumulated at least
60 min of moderate-intensity PA (as evaluated by Tritrac
accelerometer). However, some children were able to meet
the time-based recommendation without accumulating this
volume of steps/day. That is, these children could still meet
the steps/day associated with health-enhancing recommen-
dations, although still falling short of the BMI-referenced
cutoff points.
The BMI-referenced cutoff points are substantially higher
than PCPFS award threshold step counts. Part of this
elevated standard might be related to a difference in the
students who participated in the study. All the students used
in the Vincent and Pangrazi study (48) were from the
United States, whereas participants in secondary analysis by
Tudor-Locke et al. (42) were from the United States,
Sweden, and Australia. The original analysis of these data
was reported by Vincent et al. (49), and it showed that the
Australian and Swedish children accumulated significantly
higher step counts than children from the United States.
Thus, possibly these cutoff points might be closer to the
PCPFS level if they were limited to American youth.
How do children in other parts of the world compare to
the PCPFS award thresholds? Vincent et al. (49) reported
results on children, aged 6 to 12 yr, living in Australia and
Sweden. Results showed that for boys the mean values
ranged from 15,673 to 18,346 stepsId
j1
for Sweden, 13,864
to 15,023 stepsId
j1
for Australia, and 12,554 to 13,872
stepsId
j1
for the United States. Girls averaged between
12,041 and 14,825 stepsId
j1
for Sweden, between 11,221
and 12,322 stepsId
j1
for Australia, and between 10,661 and
11,383 stepsId
j1
for the United States. Furthermore, the
authors reported that the Australian values did not include a
30-min bout of swimming that these participants did most
days during the duration of the study. This study also
showed that the PA curve (i.e., a visual representation of the
natural history of PA behaviors) remained relatively flat
throughout the preadolescent years, and the rate of increase
in BMI with age was much greater in American children
than in the Swedish and Australian youth.
A study of 871 Swedish children, aged 7 to 14 yr, by
Raustorp et al. (29) showed steps/day values that ranged
from 14,911 to 16,752 for boys and 12,238 to 14,825 for
girls. A large majority of the youth (83% of boys and 82%
of girls) would have been able to reach the PCPFS award
threshold of 11,000 and 13,000 stepsId
j1
on the basis of
their accumulated values. An interesting aspect of this study
showed that there were no significant correlations between
PA level and BMI.
A study of Belgian boys and girls (5) focused on
pedometer data for 92 children aged 6 to 12 yr. Boys in
this study averaged 16,628 stepsId
j1
and girls accumulated
13,002 stepsId
j1
. In contrast to the previous studies
described, these data were gathered during the summer
months as opposed to the school year. In addition, data
were collected during the entire week, and there were no
reported differences between weekdays and weekend days.
Participants in this study were asked to fill out a PA diary
with the aid of one parent to determine the number of
minutes of MVPA they had accumulated each day. On the
basis of regression equations, 60 min of MVPA was
equivalent to 15,340 stepsId
j1
in boys and 13,130 stepsId
j1
in girls. A moderate correlation (r= 0.39, PG0.001) was
found between pedometer-determined PA and reported
minutes of MVPA. However, the authors suggested that
using steps/day to predict MVPA should be used with
caution because of a number of weak statistical indices. A
study of schoolchildren in Cyprus (23) was undertaken to
see if there was a difference in PA levels living in rural or
urban settings. The study sample included 256 Greek
Cypriot children, aged 11 and 12 yr, from two schools
representing urban areas and three schools representing
rural areas. PA levels were assessed for 4 weekdays in the
summer and 4 weekdays in the winter. Results showed that
urban schoolchildren (13,583 stepsId
j1
) were significantly
more active than their rural counterparts (12,436 stepsId
j1
)
during the winter season. However, rural schoolchildren
were significantly more active (16,450 vs 14,531 stepsId
j1
)
in the summer months. Results of this study showed that
there is a need to consider seasonal and geographical
location differences that impact PA levels of youth.
MEASUREMENT ISSUES
Steps/day guidelines have been typically established on
the basis of the norm-referenced approach, which compares
an individual’s performance to that of others. For example,
Tudor-Locke and Myers (38) reported that healthy adults
can be expected to average between 7000 and 13,000
stepsId
j1
on the basis of a simple expression of ranges of
published values at the time. As stated in the previous
sections, the PCPFS award thresholds are based on the
Vincent and Pangrazi (48) reported normative values for
children. This approach to setting cutoff points is necessa-
rily based on the average score of each targeted group.
Therefore, the guidelines may vary among different groups
of individuals, as can be seen from the discussion in the
previous section, comparing varying normative values
between geographies, climates, and seasons, to name but a
few factors. In the norm-referenced approach, an individual’s
health status is not considered in determining the guideline.
A criterion-referenced approach to setting cutoff points
considers a specific health outcome or a health risk factor as
the decisive factor. The criterion-referenced approach has
been successfully applied by several national fitness testing
programs (e.g., FITNESSGRAM). These tests have set
guidelines on the basis of the minimum level of perfor-
mance related to good health (51).
A key element of the criterion-referenced approach in
establishing pedometer-based guidelines is its link to spe-
cific health risk factors (e.g., obesity, cardiovascular disease,
diabetes). The derived cutoff point is a score on a scale
corresponding to the accepted health-related threshold of
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8
the selected health risk factor (19). As such, the cutoff
point represents an absolute protective level related to the
specific health outcome. Several methods using the criterion-
referenced approach have been introduced in the mea-
surement literature for setting standards (9,10,22). The
borderline group method and the contrasting group method are
both widely used. To establish a cutoff point using the
borderline group method (22), researchers (or practitioners)
identify ‘‘borderline’’ individuals from the sample, whose
health level approaches the intended guideline. The median
score (or other measure of central tendency) for the distribu-
tion of the borderline individuals’ performance reflects the
cutoff point. Applying this approach, researchers might
establish a steps/day cutoff point related to osteoporosis
defined by bone mineral density. Specifically, a criterion
measure of bone mineral density (i.e.,using a DEXA machine)
could be used to identify a borderline group considered
osteopenic, and the median steps/day of this group becomes
the associated pedometer-determined PA cutoff point.
To establish a cutoff point using the contrasting group
method (2,3), researchers determine two different levels of
groups from the sample (e.g., nonhealthy and healthy). The
cutoff point is then identified from the threshold between
the two groups’ distributions, that is, the point which
discriminates between the two contrasting group. For
example, to determine a steps/day cutoff point related to
osteoporosis, researchers would classify individuals into
one of two groups on the basis of their bone mineral density
level: the osteoporosis group (i.e., nonhealthy) and the
normal group (i.e., healthy). The cutoff point is the steps/
day threshold that best defines the likelihood of classifica-
tion as nonhealthy versus healthy. As discussed above,
Tudor-Locke et al. (42) provide an example of setting
pedometer-based steps/day guidelines related to healthy
body composition in children using the criterion-referenced
approach. A series of cutoff points can also be set using a
modification to the contrasting group method. Instead of
classifying individuals into two groups from the sample,
multiple groups are formed depending on the desired
number of cutoff points.
To set a defensible cutoff point, a relatively large sample
size is required for the contrasting group method (11).
Specifically, the shapes of the two distributions must be
large enough to identify the threshold on the scale
representing the boundary between two groups. This may
not be the case for the borderline-group method, in which a
median can be estimated fairly well with a relatively small
sample. The more important issue is whether the sample of
individuals is representative. If not, the resulting steps/day
cutoff point may not be externally valid (i.e., not suitable
for generalizing the guideline to the population).
Regardless of the approach, however, application of
cutoff points derived from the process of standard setting
is not always favorable; misclassification of error always
exists and may be magnified by many factors ranging from
the choice of health outcome measure used to the
participants’ motivation under testing conditions. There
are two possible types of misclassification errors: false-
positive and false-negative (31). False-positive error occurs
when nonhealthy individuals are classified as healthy
individuals. False-negative error reflects healthy individuals
who are classified as nonhealthy individuals. In terms of
pedometer-determined PA associated with a specific health
outcome, a false-positive error may be a more serious
measurement offense than a false-negative error. It may
therefore be prudent to adjust a criterion-referenced cutoff
point to a more conservative value, thereby reducing the
ratio of false-positive to false-negative errors. This strategy
would produce a more stringent steps/day cutoff point.
Although this works well from a measurement perspective,
unfortunately, the tradeoff from an individual intervention
approach may be the perception of an unattainable goal. It
is plausible that such perception, if universal, can under-
mine the well-intentioned act of setting such as public
health PA guidelines.
CONCLUSIONS
There has been increasing interest to linking health-
related outcomes to pedometer-determined PA to establish
steps/day guidelines. Although there is a growing number
of articles presenting habitual steps/day accumulated by
adults and children, little research has provided evidence on
the dose–response relationship between steps/day and
specific health outcomes. The criterion-referenced approach
to setting the steps/day guideline is favorable compared with
the more common norm-referenced approach and may
represent an absolute protective level of specific health
outcomes. A limitation, of course, is that criterion-referenced
approaches are based on cross-sectional data that must be
verified by other study designs. Further investigation is
warranted to provide evidence on the number of steps/day
relative to common health outcomes, such as coronary heart
disease, cancer, and diabetes.
Widespread acceptance of pedometers for PA measure-
ment and motivation requires evidence-based steps/day
indices associated with important health-related outcomes
and/or health-related levels of PA if their simple output is to
be interpreted and compared between populations and
studies. Setting any single cutoff point that meets the
epidemiologist’s need to classify and track populations yet
also instills a sense of achievement in those struggling to
increase their PA is a complex proposition. Although there
is much room for additional research to distill dose–response
questions, both from the validity and health messaging
perspectives, herein we proposed a zone-based hierarchy
that may be used to meet both needs, acknowledging that
the precision of pedometer-determined steps/day should not
be overstated. Bearing these issues in mind, Table 1 presents
the adult zones originally proposed by Tudor-Locke and
Bassett (36) and preliminary schematics of youth zones on
the basis of emerging criterion-based evidence reviewed in
HOW MANY STEPS ARE ENOUGH? Medicine & Science in Sports & Exercise
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Copyright @ 200 by the American College of Sports Medicine. Unauthorized reproduction of this article is prohibited.
8
the previous sections. We chose not to use the same qual-
itative descriptors for the children as used with the adults
in a conscious attempt to recognize that children are not
merely ‘‘small adults’’ and declare the greater value we
place on motivating children’s PA and avoiding untoward
labeling. We anticipate refinement as our science advances.
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Healthy Adults
a
Girls (6–12 yr)
b
Boys (6–12 yr)
b
Steps/day Zone Descriptive Category Steps/day Zone Descriptive Category Steps/day Zone Descriptive Category
Q17,500 Platinum
Q14,500 Platinum 15,000–17,499 Gold
Q12,500 Highly active 12,000–14,499 Gold 12,500–14,999 Silver
10,000–12,499 Active 9500–11,999 Silver 10,000–12,499 Bronze
7500–9999 Somewhat active 7000–9499 Bronze G10,000 Copper
5000–7499 Low active G7000 Copper
G5000 Sedentary
a
Based on the compiled evidence presented in Tudor-Locke and Bassett (36).
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Based on a criterion presented by Tudor-Locke et al. (42).
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