Exercise as it relates to Disease/Pokèmon GO as an intervention to increase physical activity in young adults

This article is a critical analysis of the paper: "Gotta catch’em all! Pokémon GO and physical activity among young adults: difference in differences study"

Background to Research
Sedentary behaviour is a global issue that negatively affects health outcomes, increasing the risk for type 2 diabetes, cardiovascular disease, osteoporosis, and breast and colon cancer. Physical activity (PA) contributes to the prevention of these conditions. However, worldwide, 28 per cent of adults aged 18 years and over are physically inactive, and do not meet the World Health Organization's (WHO) recommended guidelines of at least 150 minutes of moderate intensity or 75 minutes of vigorous intensity PA per week, or a combination of both.

In young people and adults, an increase in sedentary behaviour is predominantly due to the use of mobile devices, home-based computers, and video games. More recently, mobile exergames have grown in popularity, as they promote PA. Pokèmon GO is an augmented reality game, in which players are required to walk to capture cartoon characters that appear on their mobile phone screens. While it was not designed to promote PA, Pokémon GO increases PA through walking.

The purpose of this study was to determine whether playing Pokèmon GO influenced daily step count.

Where is the research from?
The study was conducted at the Harvard T.H. Chan School of Public Health, USA. The journal in which the study was published was BMJ, one of the world's oldest international peer-reviewed medical journals. This was the first published article of Katherine Howe, the lead researcher of the study. Howe is a doctoral candidate in the Department of Epidemiology and the Department of Social and Behavioural Sciences at Harvard University. However, the other authors have made many contributions across existing literature, in particular, Eric Rimm, with his extensive experience in epidemiology and nutrition. As none of the authors are affiliated or associated with the technology featured in this study, no bias is present.

What kind of research is this?
The research was a cohort study, in which subjects that shared common characteristics were followed over six weeks. This research method is the most advantageous in evaluating multiple outcomes and determining causality of exposures, and thus, may be more generalisable than other study designs. However, confounding variables are often a disadvantage of this method that should be considered, as it may lead to the overestimation or underestimation of an effect. There was also an experimental aspect to the design, due to the comparison of activity between players and non-players via a difference in differences analysis.

What did the research involve?
The study involved 2225 subjects who responded to an online survey conducted through a platform called Amazon Mechanical Turk (MTurk). However, only 1182 subjects were selected to participate in the study due to the criteria below. Suburb of residence, zip code, education level, household income, and body mass index were recorded. A walk score for each of the subjects' suburb of residence was then identified based on zip code, and was categorised into car dependent, somewhat walkable, very walkable, and walker's paradise.

Inclusion Criteria:


 * Subjects aged between 18-35 years.
 * Owned an iPhone 6 smartphone.
 * Lived in the US.

Exclusion Criteria:


 * Did not achieve a trainer level of 5 or more.
 * Did not complete the online survey.
 * Did not provide proof of steps data through screenshots taken on their smartphone.

For the duration of the study, all subjects submitted a screenshot of their daily step count while playing Pokèmon GO, using data recorded by the in-built phone accelerometer on the Health App on their iPhone devices.

Results
At the end of the intervention, the daily step count of non-players over the four weeks prior to installation of Pokèmon GO was compared with the daily step count of players in the six weeks following installation. The difference in differences analysis was conducted to examine the overall effect of Pokèmon GO on the number of steps. This method acts similarly to an experimental research design, whereby the change over time of a variable in the treatment group is compared with the control group.
 * Pokèmon GO increased the average daily step count by 955 during the first week following installation.
 * This increase did not remain consistent and returned to levels prior to installation by week six (on average 4256 steps daily).

Limitations
Using the iPhone Health App appeared to be inconvenient at times, as subjects had to carry their phones for steps to be recorded. Existing literature has not supported the accuracy of this technology in tracking step count. However, wrist-worn accelerometers are convenient and are associated with greater compliance, and may have been a better alternative. Secondly, limiting the research sample to Android phone users and MTurk workers limited the generalisability of the study, especially given the overrepresentation of females in MTurk workers. Lastly, the researchers acknowledged that it was difficult to distinguish between the change in daily step count when subjects were playing Pokèmon GO or doing other activities, placing the difference in differences analysis at a higher risk of confounding.

Conclusions
The findings from this study suggest that Pokèmon GO is associated with an increase in PA. Since mobile exergames are currently growing in popularity, Pokèmon GO appears to be an incentive for PA in young adults. However, it is unlikely that Pokèmon GO can be used as an alternative to replace ordinary exercise, as the aerobic adaptations produced are not significant unless players walk briskly or jog. It is also unclear whether the increase in the number of steps is sufficient to meet the PA guidelines. For example, in the present study, the change in daily step count was equal to half of WHO's PA guidelines of a minimum of 150 minutes of moderate PA per week. This means that subjects performing steps of 0.8m at 4 km/h were only doing an additional 11 minutes of walking daily. Further, another study found that an additional 2000 steps were taken daily, as opposed to only 955 reported in the present study. Additionally, there is limited evidence in other research studies to support the long-term efficacy of Pokèmon GO. Therefore, future research investigating this area of concern should emphasise the motivations to playing Pokèmon GO in combination with additional interventions, as it may assist in sustaining PA levels and achieve positive health outcomes. While the impact of Pokèmon GO on PA in young adults is minimal, it could be considered beneficial in groups unable to exercise at a vigorous intensity.

Practical Advice

 * The development of exergames that require more vigorous intensity PA to encourage exercise in technology-dependent young adults.
 * In a similar study, 70 per cent of subjects found playing Pokèmon GO with friends most enjoyable. Therefore, playing in groups may improve the long-term efficacy of the game and encourage engagement in more vigorous PA by competing with peers to catch Pokèmon.
 * To further promote and sustain PA in young adults, future research should implement behavioural change strategies.

Further Readings
Pokémon Go, go, go, gone?

Impact of Pokémon Go on Physical Activity: A Systematic Review and Meta-Analysis

“Pokémon Go!” May Promote Walking, Discourage Sedentary Behavior in College Students

Pokémon GO and physical activity among college students. A study using Ecological Momentary Assessment