Physical Activity Interventions Review
Physical Activity Interventions Review
DOI: 10.7600/jpfsm.4.187
               Abstract This review summarizes recent findings regarding the status of physical activity
               and introduces effective methods of intervention. Data from our serial cross-sectional study
               between 2003 and 2012 suggested that the decline in step counts over the last decade is mainly
               related to a reduction in non-exercise activity associated with the increased use of cell phones
               or computers and with playing video games. We then examined the effects of lifestyle inter-
               ventions using an activity monitor with computerized game functions or an activity monitor
               and Twitter on physical activity and body composition. These findings suggested that lifestyle
               interventions using both of these strategies increases daily physical activity and reduces body
               fat more effectively than using an activity monitor alone. In addition, changes in physical ac-
               tivity and in body fat were significantly correlated. We also applied a randomized intervention
               to examine an effective method of increasing physical activity levels among college physical
               education students using a pedometer. We found that using a pedometer and inducing friendly
               competition or encouragement from peers increased step counts more effectively during soccer
               classes. These findings therefore have important implications for ensuring compliance with the
               Physical Activity Reference for Health Promotion 2013 and Active Guide.
               Keywords : activity monitor, health, cell phone, personal computer, physical education class,
                            weight loss
  A             Average                                                                                   D                                            
Weekday                 
Weekend
                                                                                                                                     
Steps/day
             
                         
	 
 
 
 
  
 	 
 
	                                                 
                                                              
                           	 
	 	 	    
                                                                                                            *
                                                                                                                                 
                                                                                                                                           
 	      
      
	 
                                                                                                                                                                                  
                                                                                                                                                                            	 		
                                                                                                                                      
             
   B            Weekday
                                                                                                             E
                                                                                                                                     
             
Steps/day
                                                                                                                                                                                            *
                                                                                                                                                                                 **†
             
                                                                                                                                     
   C            Weekend
                                                                            Trend P < 0.01
             
Steps/day
                       		 	 
  
 
 	 
	 
                                                           
                         
   	 	
 
 		 
                                                                      
                      
             
                              	
                                      
                                                      
                                                              
                                                                              
                                              
                                                                                      
                                                                                              
Fig. 1	 Changes in daily step counts and daily behavior records between 2003 and 2012.
	       Average (A), weekday (B), and weekend (C) steps, playing video games per waking hours (D), and cell phone or computer us-
        age during waking hours (E). PC, personal computer. Data are shown as means ± SEM. *P < 0.05 and **P < 0.01 vs. within the
        same category in 2003-2004. †P < 0.05 vs. within the same category in 2007-2008.
	       Average and weekend step counts significantly decreased, and cell phone or computer usage significantly increased during
        weekdays and weekends between 2011 and 2012 (Nishiwaki et al., 2014)9).
computer and played video games more frequently than                                           findings indicate that declining step counts, especially
those with high step counts (Fig. 2A and B). Another                                           among youth, are mainly related to a reduction in non-
recent study found that cell phone usage can disrupt PA                                        exercise activity associated with increased cell phone or
and reduce cardiorespiratory fitness determined as peak                                        computer usage and playing video games. Thus, increases
oxygen consumption14), and that reductions in step counts                                      in daily PA habits17), improvements in PA modes18) and
are associated with increasing Internet addiction levels in                                    better city planning that includes environmental improve-
a dose-response manner (Fig. 2C)15). Screen time is also                                       ments 19,20) are needed to increase the amount of non-
inversely associated with isometric trunk muscle strength                                      exercise activities.                                              	
independently of cardiorespiratory fitness and other con-
founding factors in youth16). Thus, technological devel-
                                                                                               Monitoring physical activity and behavioral modification
opments such as the Internet and cell phones can reduce
daily PA since less energy is needed for non-exercise ac-                                        Pedometers and activity monitors serve as surveillance
tivities. Although current evidence remains limited, these                                     tools to assess step counts or the amounts of PA. How-
                                                                   JPFSM : Physical activity and intervention                                          189
   A                                                     
High steps group         C                              Trend P < 0.05
        Playing video games (%)
                                      
                                                          
Low steps group
                                                                                             
                                                                 P < 0.05
                                                                                   Steps/day
                                      
                                                                                                
                                                                                                
                                                                                                       
	
   
   
      
                                             		                                                                        
                                                                                          
                                                                                                                 
            
                                                                 
                                                                
                      
   B                                                                                                        
        Cell phone or PC usage (%)
ever, a meta-analysis of eight randomized controlled trials                                     reported that activity monitors and rewards such as being
and 18 observational studies found a significant increase                                       able to watch television induce increases in PA among
of 2000 to 2500 steps/day among pedometer users com-                                            children 27). Because participants become absorbed in
pared with control participants or baseline counts21). These                                    playing interactive video games and perceive them as en-
findings suggested that the immediate feedback provided                                         joyable, such games can serve as an additional interven-
by the activity monitor or pedometer is an important mo-                                        tion to encourage compliance with exercise or rehabilita-
tivational feature that serves as a behavioral modification                                     tion programs28-32). Therefore, wearing an activity monitor
tool. Clemes et al. have also found a significant mean in-                                      as a motivational tool and incorporating behavior-based
crease of 1000 to 1800 steps/day when participants wear                                         rewards or a computerized game element might have a
an unsealed pedometer and keep a personal activity log of                                       collective effect on increasing daily PA. Thus, our pilot
their daily step counts, compared with wearing a covert                                         crossover study analyzed the effects of a short-term life-
(uninformed device and measured values) or a sealed (un-                                        style intervention using an activity monitor with comput-
informed measured values) pedometer22,23). That is, being                                       erized game functions on PA33).
aware of wearing an activity monitor or pedometer and                                              Healthy volunteers who participated in the 12-week
confirming the measured values can induce an increase                                           crossover study were randomly assigned to either group
in daily PA or step counts. Therefore, in addition to being                                     A (six-week game intervention followed by a six-week
a surveillance tool, pedometers and activity monitors can                                       normal intervention) or group B (six-week normal inter-
serve as motivational devices that can induce behavioral                                        vention followed by a six-week game intervention). The
modifications. Indeed, many studies have indicated that                                         participants wore both a Lifecorder EX standard activity
lifestyle interventions using activity monitors or pedom-                                                                        	
                                                                                                monitor (Suzuken Co., Nagoya, Japan) and the Yuuhokei
eters can increase regular PA and help to prevent the onset                                     activity monitor with computerized game functions (Ban-
of lifestyle-related diseases24-26).                                                            dai Co. Ltd., Tokyo, Japan) during the game intervention
                                                                                                and only the standard activity monitor during the normal
                                                                                                intervention.
Effects of an activity monitor with computerized game
                                                                                                   Fig. 3A and B shows that significantly more daily steps
functions
                                                                                                were recorded and significantly more PA performed at an
  We aimed to determine more effective methods of using                                         intensity of ≥ 3 METs for the game, than for the normal
activity monitors or pedometers as follows. Others have                                         intervention (both P < 0.01). The mean differences in
190                                                     JPFSM : Nishiwaki M and Matsumoto N
steps and the amount of PA between the game and normal                    of daily PA levels might be limited. If the goal is 10000
interventions were 1673 ± 1738 steps (21.9 ± 24.0%)                       steps/day, then the target value for each game to proceed
and 0.7 ± 0.8 METs (33.6 ± 38.2%), respectively. The                      to the next scene should be set at 8000 steps, which ap-
Yuuhokei, which was used as the activity monitor with                     proximately corresponds to 10000 steps counted by the
computerized game functions in this study, is visually                    Lifecorder EX.
simple to understand and displays step counts until a goal
is achieved. Moreover, the game characters in Yuuhokei
                                                                          Effects of an activity monitor and Twitter
usually encourage the users to achieve step-count mile-
stones or physical activity levels. Because the games in-                    One study has found that exercising with a virtual part-
cluded in Yuuhokei are based on stories and tales that are                ner through a brief video chat via services such as Skype
very famous in Japan, such as Space Battleship Yamato,                    can improve aerobic exercise performance across multiple
the Rose of Versailles, and Section Chief Kousaku Shima,                  sessions38). These findings suggested that friendly compe-
participants easily became absorbed in increasing PA to                   tition or encouragement from online partners can increase
clear the game. Collectively, the game story, scenes, and                 motivation in both exercise and non-exercise activities,
characters might help to motivate individuals to walk or                  thereby increasing daily PA. Although recent reports have
be active and make them even more aware of daily PA                       described a web-based PA diary39-41), not everyone can
levels and step goals. Therefore, these findings suggest                  utilize large-scale systems. Thus, we considered social
that short-term interventions using an activity monitor                   networks such as Twitter, which enables users to send and
with computerized game functions increases PA more ef-                    read short 140-character messages (tweets) that an indefi-
fectively than those using a standard activity monitor.                   nite number of individuals can easily and immediately
   However, despite a significant correlation between step                share or exchange via tweets, retweets, and timelines. In
counts obtained from the Yuuhokei and the Lifecorder EX                   addition to being aware of wearing the monitor and con-
(r = 0.92), significantly fewer steps were counted by the                 firming measured values, adding Twitter might promote
former than the latter (7165 ± 4284 steps/day vs. 10132                   daily PA or reduce sedentary behavior through friendly
± 4841 steps/day, P < 0.01)34). The accuracy of the step                  competition with, and/or encouragement from online part-
counts detected by Lifecorder EX is calibrated during the                 ners. Thus, we investigated the effects of a randomized
manufacturing process according to the Japanese Indus-                    lifestyle intervention using an activity monitor and Twit-
trial Standards (JIS), and the widely accepted error during               ter on PA42).
walking on a treadmill is within 1%35-37). Therefore, these                   Healthy participants were randomly assigned to either
results infer that although relative changes in daily indi-               a Normal intervention group that wore a Lifecorder EX
vidual step counts determined from the Yuuhokei might                     activity monitor or a Twitter intervention group that wore
help to evaluate daily PA, the application of absolute step               the same activity monitor and tweeted about their daily
counts obtained from this device as a proxy assessment                    steps or PA for six weeks. An observer read the tweets
                                                                              Physical activity (METs	h/day)
                   A                                                     B
                                                                                                           
                      Steps (Steps/day)
                                           
                                                                                                                
                                           
                                                                                                                
                                           
                                                                                                                
                                           
                                                                                                                
                                           
                                                                                                            
                                                                                                            
                                                   Normal      Game                                               Normal   Game
from each participant and commented about PA. The pro-                                               perimental period in the Twitter group (Fig. 4C). Friendly
tect mode was configured for each account to safeguard                                               competition or encouragement from online partners such
the data of each participant.                                                                        as other participants in the Twitter group in addition to be-
   Daily PA (step counts and amount of PA) did not sig-                                              ing aware of wearing an activity monitor and confirming
nificantly differ at week one between the groups and did                                             the measured values might help to motivate participants
not significantly differ over the six-week experimental                                              to become more active and cause them to become even
period in the Normal group. In contrast, step counts (Fig.                                           more conscious of daily PA levels and step goals. There-
4A) and the amount of PA (Fig. 4B) gradually increased                                               fore, these data indicated that daily PA increased more
from weeks one to six in the Twitter group from 8542 ±                                               effectively when a lifestyle intervention comprised an ac-
3158 to 12700 ± 3935 steps/day and from 2.5 ± 1.2 to 4.6                                             tivity monitor and Twitter rather than an activity monitor
± 2.3 METs·h/day (both P < 0.01). Moreover, step counts                                              alone.
significantly declined immediately after the end of the ex-
A B : Normal group
                         
                        
                         
   Steps (steps/day)
                                                                                                                      
                         
                        
                                                                                                                                              
                                                                                                                                                 
                                                                   **     **                                                                         **
                         
                        
                                          ** **                                                                                               **
                                                                                                                                      *   *
                        
                         
                         
                          
                         
                                                                                                               
                          
                         
                          
                          
                         
                                                                                                               
                                       1   2   3     4        5     6(week)                                           1    2    3     4   5   6(week)
     C
                        
                                                                                                                                                : Normal group
                                                                                                                                                : Twitter group
  Steps (steps/day)
                             
                                       1   2   6     7        8      9     10 11 12 13 14(week)
                A                            Normal Twitter
                                                                           B                      
                                                                                                                   r = -0.713, P = 0.031
                                                                                                                   y = -0.2059x -0.5727
                                                                       Change in body fat (kg)
                                      
           Change in body fat (kg)
                                      	
                                                -0.1   -1.1
                                                 ±      ±                                         
                                      
                                                0.3   0.2
                                      
                                                                                                  
                                      
                                      
                                                                                                  
                                                                                                                               
                                      	
                                                 P = 0.021
                                                                          Change in amount of PA (METs	h/day)
filiation courses. Both groups participated in four 90-min                                 from baseline to fourth class for the Intervention group
PE classes and initially wore a sealed (uninformed mea-                                    compared with the Control group and no significant dif-
sured values) pedometer to assess baseline step counts                                     ference between the Control and the Half-intervention
at the first class. The Control group continued to wear a                                  groups. Thus, in addition to being aware of wearing a
sealed pedometer for the next three classes, whereas the                                   pedometer and confirming measured values, friendly
Intervention group wore an unsealed pedometer (informed                                    competition or encouragement from other students tak-
measured values) and recorded their step counts in a team                                  ing the same class might cause participants to become
activity log. Victory and defeat were decided by both the                                  more active. Such PE classes using a pedometer might
step counts of team members and the soccer game scores.                                    also positively affect game and point scores in college PE
Thus, the students in the Intervention group were encour-                                  classes47). Collectively, our findings suggest that wear-
aged to increase their step counts.                                                        ing pedometers can increase step counts more effectively
   Because we excluded all data missing values from sta-                                   during PE classes when the players participate in friendly
tistical analyses, data for the remaining 43 (the Control                                  competition or are encouraged by other students.
group) or 62 (the Intervention group) participants were
analyzed. Baseline step counts per class did not signifi-
                                                                                           Summary
cantly differ between the groups, and the step counts did
not significantly change over time in the Control group.                                     A lack of physical activity is often considered as a glob-
However, step counts for the Intervention group gradu-                                     al pandemic and the reductions in step counts or PA can-
ally increased between baseline and the fourth class (4502                                 not be ignored to reduce the risk for NCD. Some evidence
± 123 steps/class vs. 5539 ± 119 steps/class; P < 0.01;                                    indicates that the decline in step counts over the last
Fig. 6A). Furthermore, we analyzed the effects of a half-                                  decade is mainly related to a reduction in non-exercise
intervention on step counts. The participants in this half-                                activity associated with increased cell phone or computer
intervention (n = 51) wore an unsealed pedometer and re-                                   usage and playing video games. Therefore, pedometers or
corded their step counts in an individual activity log, and                                activity monitors that can induce behavioral modifications
did not compete against other teams for step counts. Fig.                                  should be used as motivational devices to increase step
6B shows a significantly greater change in step counts                                     counts or PA. Our findings suggest that lifestyle interven-
        A                                                                                     B
                                                                                      Change in steps from baseline (%)
 Steps/Physical education class
                                                         a                                                                
                                                                                                                                              21.2        26.7
                                                                                                                                       ±           ±
                                                                                                                                              5.3        4.0
                                                                                                                                 7.2
                                                                                                                                    ±
                                                                                                                       
                                                                                                                                   4.2
                                           Baseline   1        2           3                                                 Normal       Half-
                                                                           (class)                                                       Intervention Intervention
tions using an activity monitor with computerized game                      global action for public health. Lancet 380: 294-305.
functions or an activity monitor and Twitter increase daily            12)	The Office for Lifestyle-Related Diseases Control, General
PA and reduce body fat more effectively than an activity                    Affairs Division, Health Service Bureau, Ministry of Health,
monitor alone. In addition, using pedometers along with                     Labour and Welfare of Japan. 2006. Exercise and Physical
                                                                            Activity Guide for Health Promotion 2006 - To Prevent Life-
friendly competition or encouragement from peers during
                                                                            style-related Diseases - (in Japanese).
PE activities might increase step counts among college
                                                                       13)	The Office for Lifestyle-Related Diseases Control, General
students more effectively than participating in such activi-                Affairs Division, Health Service Bureau, Ministry of Health,
ties without these stimuli. These findings therefore have                   Labour and Welfare of Japan. 2006. Exercise and Physical
important implications for ensuring compliance with the                     Activity Reference for Health Promotion 2006: Physical Ac-
Physical Activity Reference for Health Promotion 2013                       tivity, Exercise, and Physical Fitness (in Japanese).
and Active Guide48,49).                                                14)	Lepp A, Barkley JE, Sanders GJ, Rebold M and Gates P.
                                                                            2013. The relationship between cell phone use, physical and
                                                                            sedentary activity, and cardiorespiratory fitness in a sample
Conflict of Interests                                                       of U.S. college students. Int J Behav Nutr Phys Act 10: 79.
  The authors declare that there is no conflict of interests           15)	Nishiwaki M, Kiuchi A and Nakamura T. 2014. The rela-
                                                                            tionship between Internet addiction and steps -A cross-sec-
regarding the publication of this article.
                                                                            tional study in a sample of male college freshmen in Japan-.
                                                                            Tairyoku Kagaku (Jpn J Phys Fitness Sports Med) 63: 445-
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