The 30-second article
• Pedometers have been used for
decades to measure the number of
steps taken by individuals
• Focus is now switching to ‘step rate’
e.g. steps per minute, rather than
just number of steps
• This study investigated steps rates
in children to gauge whether usual
walking speeds were fast enough to
constitute moderate intensity
exercise
• The self-selected pace of the young
participants was found to be too
slow to elicit the benefits associated
with moderate intensity exercise
• The researchers identified
recommended walking paces for
children of different ages and
weights.
equivalents (A-AMET) for each participant,
where A-AMET = –0.75363 + (step rate ×
–0.02242) + (step rate2 × 0.000277) + (BMI
weight status × 0.849469) + (age × 0.218567).
This equation was necessary as the 3 and
4 A-AMETs have been shown to represent
moderate-intensity activity.
Results: 22 participants completed the
testing. Table 1 illustrates the age-adjusted
METs and the step rate.
The authors concluded from their
findings that the self-selected pace of the
young participants (2.2km/h and 90 steps
per minute) was not adequate to elicit a
moderate intensity of exercise. With regard
to recommendations, they found that in order
to represent moderate intensity exercise,
healthy weight individuals aged 9 and 10
should walk at a pace of between 120 and
140 steps per minute, while 11 and 12-yearolds should walk at a pace of between 110
and 130 steps per minute. If the children were
overweight or obese, the 9 and 10-year-olds
should walk at a pace of 110 to 130 steps per
minute and 11 and 12-year-olds between 100
and 120 steps per minute.
Pros: This was a good, unique study.
Most importantly, the researchers were able
to identify an age- and weight/BMI-specific
A-AMET’s and step rates.
Many children now have smartphones
Table 1: Age-adjusted METs and step rate
A-AMET
Walk speed (km/h)
Step rate (steps/min)
Mean
SD
Mean
SD
• Self-selected
2.2
0.3
90
13
• 4.0
2.9
0.3
112
7
• 4.8
3.4
0.5
121
7
• 5.6
4.0
0.6
131
9
containing apps that allow the phone to be
used as a high-tech pedometer. In fact a
recent (2015) article published in the Journal
of the American, Medical Association (Case
et al., (2015) ‘Accuracy of Smartphone
Applications and Wearable Devices for
Tracking Physical Activity Data’, 313(6):625626) found the smartphones to be more
accurate than the wearable devices.
Although the article used adults as the
participants, there is clearly potential benefit
in using a smartphone.
Given the study objective was to
determine the step rate at moderate-tovigorous
intensity
exercise that is both
ageand
weight/
BMI-specific,
we
would have expected
them to incorporate the use of
a treadmill and/or heart rate using
expired gas analysis. Their approach is
novel, however has some limitations.
Cons: It would have been beneficial for
the researchers to have a larger sample size
and use heart rate monitors and expired
gas analysis to compare to their predicted
results. Fitness professionals should
preference pedometers and smartphone
applications that also provide step rate.
Pedometer companies and app designers
should include step rate functionality, which
should be a simple task given that these
devices have a time function.
Associate Professor Mike Climstein, PhD FASMF
FACSM FAAESS is one of Australia’s leading
Accredited Exercise Physiologists and researchers.
[email protected]
Joe Walsh, MSc is a sport and exercise scientist.
As well as working for Charles Darwin and Bond
Universities, he is a director of Fitness Clinic in Five
Dock, Sydney. fitnessclinic.com.au
NETWORK SPRING 2015 | 25