UNIVERSIDADE DE LISBOA
Faculdade de Ciências
Departamento de Informática
EXODUS – EXERGAMES FOR UBIQUITOUS
SCENARIOS
Paulo Alexandre André Ribeiro
DISSERTAÇÃO
MESTRADO EM ENGENHARIA INFORMÁTICA
Especialização em Sistemas de Informação
UNIVERSIDADE DE LISBOA
Faculdade de Ciências
Departamento de Informática
EXODUS – EXERGAMES FOR UBIQUITOUS
SCENARIOS
Paulo Alexandre André Ribeiro
DISSERTAÇÃO
MESTRADO EM ENGENHARIA INFORMÁTICA
Especialização em Sistemas de Informação
Trabalho orientado pelo Prof. Doutor Luís Manuel Pinto da Rocha Afonso Carriço e co-orientado por Luís Miguel Santos Duarte
Agradecimentos
Gostaria de expressar a minha gratidão ao meu orientador, o Professor Luís Carriço e ao meu co-orientador Luís Duarte pelos comentários, observações e compromisso prestados durante todo o processo de aprendizagem e trabalho desenvolvido com esta tese de mestrado. Além disso, gostaria também de agradecer-lhes por me terem apresentado ao tópico, bem como pelo apoio dado ao longo do caminho. Adicionalmente, gostaria de agradecer ao Professor Tiago Guerreiro por todo o contributo e aconselhamento providenciado no decorrer deste trabalho. Também gostaria de agradecer a todos os participantes que contribuíram para o meu estudo e sessões de teste, que voluntariamente compartilharam o seu precioso tempo durante todo este processo.
Eu devo a minha mais profunda gratidão à minha família, aos meus pais e avós, que me apoiaram durante todo o processo, tanto mantendo-me harmonioso como ajudando-me a “juntar as peças”. Estarei eternamente grato pelo vosso amor e apoio bem como pela paciência com que toleraram o meu egoísmo ao longo do caminho.
Não posso terminar estes agradecimentos sem mencionar o meu mais sincero agradecimento para todos os meus colegas com quem partilhei estes últimos anos, procurando arduamente concluir com êxito o curso. Nós derramámos suor, sangue e lágrimas, mas valeu a pena!
Finalmente, também gostaria de expressar a minha gratidão à FCT (Fundação para a Ciência e Tecnologia) pelo seu apoio financeiro.
Acknowledgements
I would like to express my gratitude to my supervisor, Professor Luís Carriço and to my co-supervisor Luís Duarte for the useful comments, remarks and engagement through the learning process and work developed with this master thesis. Furthermore I would like to thank them for introducing me to the topic as well for the support given on the way. In addition, I would also like to thank Professor Tiago Guerreiro for all the useful input and advice provided during the course of this work. Also, I would like to thank all the participants in my survey and testing sessions, who have willingly shared their precious time during the process.
I owe my deepest gratitude to my loved ones, my parents and my grandparents, who have supported me throughout the entire process, both by keeping me harmonious and helping me putting pieces together. I will be forever grateful for your love and support as well as your patience for putting up with my selfishness along the way.
I cannot end these acknowledgements without mentioning my heartfelt appreciation for all my colleagues with whom I shared these last years, striving to successfully conclude the course. We shed sweat, blood and tears together but it paid off!
Finally, I would also like to express my gratitude to the FCT (Fundação para a Ciência e Tecnologia) for their financial support.
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Resumo
A indústria de videojogos é uma indústria que está sempre em expansão. As pessoas gostam de jogar porque isso proporciona-lhes momentos de diversão e serve como uma forma de interação social com outros jogadores. Nos últimos anos, os avanços de hardware possibilitaram a criação de novos e mais envolventes jogos que abriram as portas do mundo dos jogos para jogadores não tradicionais e permitiu a criação de novos sistemas de interação. Exergames, jogos que requerem atividade física, fazem uso destas novas formas de interação onde normalmente é necessário o uso do corpo inteiro dos jogadores como um controlador. Este desenvolvimento abriu uma gama mais ampla de possibilidades e modelos para usar em cenários ubíquos. Fazendo uso de periféricos e dispositivos de última geração, os exergames podem ter contextos fixos e móveis, objetivos diferentes e proporcionar melhores interações sociais, através do uso de diferentes modalidades.
Exergames traduzem-se por um subconjunto de sistemas de esforço, ao qual denominamos aplicações móveis de esforço (MEA). Estas aplicações têm como finalidade auxiliar atletas amadores e profissionais durante as suas sessões de atividade física. As MEA ajudam ainda os seus utilizadores a monitorizar a sua localização durante as suas atividades de esforço, aproveitando a sua natureza ubíqua e o conjunto de recursos disponibilizados pelos dispositivos móveis modernos, agora equipados com sensores GPS, câmaras de alta qualidade ou sensores complementares de saúde (por exemplo um eletrocardiograma para monitorização de batimento cardíaco). Estes factos permitem aos programadores e investigadores visionar a criação de aplicações que oferecem a possibilidade de seguir a localização de um jogador no mundo real. Também possibilitam a distribuição espacial de vários jogadores por espaços virtuais mapeando a sua localização real, bem como oferecer suporte a uma variedade de recursos que permitem aos jogadores analisar o seu desempenho, durante ou após as suas sessões de treino. Possibilitam ainda a comparação entre os seus dados estatísticos com os dados estatísticos de outros jogadores. Estes dispositivos também disponibilizam várias modalidades de input e output fazendo uso de mensagens áudio, feedback visual e modalidades baseadas em toque que podem ser utilizadas de forma independente ou em combinação.
Aplicações que requerem esforço físico por parte dos seus utilizadores necessitam de mecanismos que lhes permitam influenciar os seus utilizadores, motivando-os a executar as diversas atividades de esforço requeridas, adotando e mantendo os comportamentos esperados para este tipo de atividades. Para alcançar este objetivo, diversas técnicas de persuasão podem ser incorporadas nestas aplicações. Geralmente, a
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persuasão está presente no nosso dia-a-dia, seja através de anúncios, propaganda politica, mass media, entre outros. Estas áreas de persuasão operam na tentativa de nos influenciar ou convencer de algo, o que se traduz no objetivo primordial da persuasão enquanto conceito: convencer um público-alvo a interiorizar o argumento persuasivo e a adotar essa nova atitude como perfazendo parte das nossas crenças. Áreas de entretenimento, como a de jogos, apontam a um público-alvo tendencialmente mais aberto a elementos persuasivos. Persuasão torna-se numa muito útil ferramenta quando acoplada com sistemas de esforço. A motivação dos jogadores pode ser influenciada por elementos persuasivos, implementados neste tipo de sistemas, recorrendo a contingências de comportamento e atores sociais persuasivos.
Compreender as variáveis que envolvem o comportamento é essencial para a conceção de técnicas persuasivas. Contingências de comportamento são compostas por três elementos principais relacionados linearmente (antecedentes, comportamento e consequências). Antecedentes traduzem-se por estímulos que precedem um comportamento, ou melhor, que levam a um comportamento específico. Consequências são o resultado de um comportamento e também dos antecedentes que o precederam, essencialmente, sendo estímulos que se seguem ao comportamento. A análise desta relação leva a perceber que tanto os antecedentes como as consequências ajudam na formulação de determinados comportamentos, o que é a própria finalidade das técnicas de persuasão.
Um sistema informático é capaz de desempenhar o papel de um ator social persuasivo convincente, capaz de criar e manter um relacionamento com os seus utilizadores. Combinando a forma como as pessoas respondem aos computadores, influências sociais e dinâmicas podem desempenhar um papel significativo com os fatores de persuasão aplicados a esses meios tecnológicos, especialmente quando estão envolvidos jogos. Como tal, a pressão de outros intervenientes (colegas ou desconhecidos) e comparação social (entre outros) torna-se num forte motivador para os jogadores / utilizadores desses sistemas. Assim sendo, o design destas aplicações deve procurar refletir a melhor qualidade e repetição possíveis para as diversas sugestões sociais (social cues) utilizadas, de modo a evitar o risco de deixar os jogadores aborrecidos ou mesmo zangados.
ExodUS é um trabalho que tem como objetivo estudar as características persuasivas presentes em exergames e aplicações móveis de esforço no geral. Estas técnicas podem contribuir para o sucesso comercial deste tipo de aplicações, bem como para a motivação dos seus utilizadores ajudando-os a obterem melhores desempenhos e resultados. Estudar como a interação social contribui para a motivação dos jogadores explorando os casos onde os jogadores competem e / ou cooperam entre si é um dos
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objetivos deste trabalho. Além disso, perceber o que promove este tipo de interações é outro dos propósitos. Dado que o tópico gira em torno de exergames e aplicações de esforço, torna-se impossível dissociar os aspetos físicos inerentes ao tipo de atividades incitadas por estas aplicações / jogos. Assim, o uso de dados de esforço, mais concretamente a forma como são utilizados e transmitidos aos utilizadores, torna-se num dos pontos secundários abordados neste trabalho. Durante atividades de esforço tradicionais, é usualmente apresentada ao utilizador informação relacionada com a atividade específica realizada. No nosso âmbito, este procedimento pode ser replicado, selecionando cuidadosamente os dados e a forma de como são apresentados ao jogador, uma vez que pode, potencialmente, influenciar o seu comportamento antes, durante e após a execução das suas sessões de treino.
Para alcançar os nossos propósitos foi realizada uma análise abrangendo duas etapas: a criação de um questionário cujo objetivo traduzia-se na formulação de uma caracterização da relação dos utilizadores com este tipo de aplicações e respetivas atividades e uma revisão das aplicações disponíveis no mercado. Pontos aos quais demos especial enfâse prendem-se com a proficiência dos utilizadores com dispositivos móveis (incluindo as funcionalidades disponibilizadas por esses mesmos dispositivos), a sua frequência de uso (tanto do dispositivo, como das aplicações em questão) e a perceção das funcionalidades persuasivas empregues nos produtos comerciais disponíveis no mercado. O resultado desta análise permitiu a definição de um espaço de desenho para aplicações móveis de esforço persuasivas, consolidando o conhecimento existente sobre persuasão e aplicações móveis de esforço.
De modo a validar o nosso modelo de desenho, foi concebido um novo sistema apoiado sobre uma aplicação móvel de esforço focada em atividades físicas semelhantes a jogging. Este sistema faz uso de diversas técnicas persuasivas concebidas para estudar a sua influência na motivação dos seus utilizadores. Uma experiência foi realizada, recorrendo ao nosso sistema, cujo principal objetivo abrangeu testar os diferentes fatores persuasivos implementados no mesmo, analisando se os jogadores se sentiam mais motivados com os modos de jogo disponíveis. Os resultados permitiram identificar alguns dos tipos de técnicas de persuasão usadas em aplicações móveis de esforço, bem como provam que o uso destas técnicas pode influenciar a motivação dos utilizadores. Adicionalmente, podemos também afirmar que aplicações móveis de esforço que não empreguem qualquer tipo de técnica de persuasão não afetam ou prejudicam a motivação dos utilizadores.
Palavras-chave: Interface de esforço, Exergames, Computação Móvel, Interfaces
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Abstract
Exergames translate into a subset of effort systems, which we call mobile exertion applications (MEA). These applications aid users in tracking their exertion activities by capitalizing on the ubiquitous nature and feature sets of modern mobile devices. Applications that require physical effort from their users need mechanisms that allow them to influence their users, motivating them to perform the various effort activities, adopting and maintaining behaviors expected for this type of activities. To achieve this goal, various persuasion techniques can be incorporated into these applications.
ExodUS is a work that aims to study persuasive features present in exergames and MEA´s in general. These techniques contribute to motivate users to perform better. Studying how social interaction contributes to the motivation of the players by exploring cases where players compete / cooperate with each other is an aim. Since this work revolves around exergames and MEA´s, it becomes impossible to separate the physical aspects inherent to the type of activities instigated by these applications. Thus the use of exertion data, more specifically how it is used and transmitted to users becomes a secondary point of this work.
For our purposes, we performed an analysis whose results allowed the definition of a design space for MEA´s, consolidating existing knowledge about persuasion and MEA´s. To validate this design model, we developed a mobile exertion application system that makes use of several persuasive techniques designed to study their influence on players´ motivation. Experimentation with ExodUS allowed for the identification of some of the types of persuasive techniques used in MEAs, as well as to prove that the use of these techniques can influence the motivation of users. Additionally, we can also state that mobile exertion applications that do not employ any type of persuasive technique do not affect or hinder the motivation of its users.
Keywords: Exertion Interface, Exergames, Mobile Computing, Persuasive Interfaces,
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Content
List of Figures ... xii
List of Tables ... xiv
Chapter 1 Introduction ... 2
1.1 Motivation ... 3
1.2 Benefits of Exergaming ... 4
1.2.1 Physical Standpoint Effectiveness ... 4
1.2.2 Cognitive Benefits ... 4 1.3 Goals ... 5 1.4 Contributions ... 6 1.5 Planning ... 7 1.5.1 Schedule ... 7 1.6 Document Structure ... 9
Chapter 2 Related Work ... 10
2.1 Persuasion Definition ... 10
2.2 Persuasion Factors ... 11
2.2.1 Contingencies and Behavior ... 11
2.2.2 Persuasive Models and Technology ... 14
2.2.3 Persuasion Approach... 20
2.3 Exergame Design ... 20
2.3.1 Design Considerations ... 20
2.3.2 Persuasive Driven Design ... 22
2.3.3 Design Approach ... 27
2.4 Exertion Applications ... 28
2.4.1 Exertion Applications Overview ... 29
2.4.2 MEA´s and Exergames ... 29
2.4.3 Bridging Exercise and Entertainment ... 35
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Chapter 3 A Design Space for Persuasive MEA ... 38
3.1 Assessing Mobile Exertion Applications Usage ... 38
3.1.1 Mobile Technology Usage ... 39
3.1.2 Exertion Habits ... 42
3.1.3 Mobile Exertion Applications Usage ... 43
3.1.4 Dealing with Persuasion ... 43
3.1.5 Survey Discussion ... 44
3.2 Mobile Exertion Application Design Space ... 45
3.2.1 Summary of MEA Features ... 45
3.2.2 Defining the MEA Design Space ... 47
3.2.3 Scenarios ... 52
3.2.4 Design Space Discussion ... 54
Chapter 4 ExodUS ... 56
4.1 System Overview ... 56
4.1.1 System Components ... 56
4.1.2 System Architecture ... 57
4.1.3 Dispatch Server Overview ... 58
4.1.4 Databases Overview ... 61
4.1.5 Component Communication ... 63
4.1.6 Web Platform Overview ... 66
4.1.7 Mobile Application Overview ... 69
4.2 System Review ... 86
Chapter 5 Experimentation with ExodUS ... 88
5.1 Experiment ... 88 5.1.1 Goals ... 89 5.1.2 Methodology ... 89 5.1.3 Participants ... 89 5.1.4 Responsibilities ... 92 5.1.5 Equipment ... 92
x 5.1.6 Procedure ... 92 5.2 Results ... 94 5.2.1 Findings ... 94 5.2.2 Anecdotal Evidence ... 103 5.3 Experiment Limitations ... 104 5.4 Experiment Discussion ... 104
Chapter 6 Conclusions & Future Work ... 108
6.1 Future Work ... 109
Bibliography ... 110
Annex I Assessing MEA Usage Questionnaire ... 114
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List of Figures
Figure 1 – Three-term contingency relationship ... 12
Figure 2 – Persuasive Technology Design in Eight-Steps ... 18
Figure 3 – The Dual Flow Model for exergaming ... 24
Figure 4 – Dual Flow Model Exergame Framework ... 24
Figure 5 – The Exertion Framework ... 26
Figure 6 – ExodUS Survey mobile device usage ... 39
Figure 7 – ExodUS Survey mobile device provided technologies ... 40
Figure 8 – ExodUS Survey participants´ exercise frequency ... 42
Figure 9 – ExodUS Survey participants´ reasoning behind exercising activities ... 42
Figure 10 – ExodUS System Architecture illustrating all components and interactions between them ... 58
Figure 11 – Generic RPC communication Sequence Diagram illustrating a request from the systems´ front-end / client side ... 58
Figure 12 – Server managed Database Class Diagram ... 62
Figure 13 – Mobile App managed Database Class Diagram ... 63
Figure 14 – ExodUS Live Broadcast Sequence Diagram example ... 64
Figure 15 – ExodUS Website social interface options ... 67
Figure 16 – ExodUS Website Player History ... 68
Figure 17 – ExodUS Mapping of the Tracked Workout Session ... 70
Figure 18 – ExodUS Exertion Data Structure representation ... 74
Figure 19 – 2-axis graph representation of a players´ distance metric ... 75
Figure 20 – 2-axis graph representation of a players´ velocity metric... 76
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Figure 22 – ExodUS Settings Screen showing the Player Profile ... 78
Figure 23 – ExodUS Friend / Buddy list Screen ... 79
Figure 24 – ExodUS playable Activities and Workout Types ... 80
Figure 25 – ExodUS Player History Screen ... 81
Figure 26 – Selectable options for the various workout sessions recorded on the Player History ... 82
Figure 27 – ExodUS Player History Data Synchronization Screen ... 82
Figure 28 – ExodUS hierarchy of feedback types and respective modalities ... 84
Figure 29 – ExodUS Experiment participants´ gender distribution ... 90
Figure 30 – ExodUS Experiment participants´ exercise frequency ... 90
Figure 31 – ExodUS Experiment participants´ reasoning behind exertion activities ... 91
Figure 32 – ExodUS Experiment participants´ reasoning behind their use of MEA´s ... 91
Figure 33 – ExodUS Experiment Location ... 93
Figure 34 – MEA Presence only impact on player motivation ... 95
Figure 35 – Audio performance updates´ impact on player motivation ... 96
Figure 36 – Co-located Real World Opponent plus MEA Audio performance updates´ impact on player motivation ... 96
Figure 37 – Co-located Real World Opponent plus MEA Audio performance updates´ impact on player emotional state ... 97
Figure 38 – Virtual Partner ‘Ghost’ Challenge impact on player motivation ... 98
Figure 39 – Virtual Partner ‘Ghost’ Challenge impact on player emotional state .. 98
Figure 40 – Live Broadcast Challenge with the presence of spectators´ impact on player motivation ... 99
Figure 41 – Presence of spectators´ impact on player emotional state ... 99
Figure 42 – Audio Cue effectiveness ... 100
Figure 43 – Live Broadcast Challenge Audio Cue effectiveness ... 101
xiv
List of Tables
Table 1 - Behavior Qualities and their effects ... 13
Table 2 – Foggs´ Primary Types of Social Cues ... 15
Table 3 – Features of historical exergame products ... 33
Table 4 – ExodUS survey participants´ age group distribution ... 39
Table 5 – MEA distribution in our design space ... 52
Table 6 – ExodUS system distribution in our design space ... 86
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Chapter 1
Introduction
In the old days people used to play games with each other using physical artifacts such as cardboards and pieces. Other popular games like Hide and Seek, did not require the use of items, could be played almost everywhere and did not have a limit for the number of players. These old traditional games encouraged players to spend time outside their homes and gather with friends to play. These characteristics lead players to have fun, exercise and build relationships that otherwise they might have not built. The introduction of personal computers gave users other possibilities for gaming, such as racing with each other without being in the same physical space. Older games were replicated in digital versions able to run on computers and players were able to play either against an artificial opponent or against other people. But although personal computers took away the need to physically gather with friends and to go outside to play with networked games (where players can interact with each other and enjoy playing together), it still led to the majority of players to a sedentary lifestyle with weak social relations.
Nowadays people take their smartphones or their tablets and play games wherever they may be. This fact gives us new windows of opportunity, new directions in the design of games, especially in games which promote exertion activities. One of the latest trends in the industry is the concept of exergames. Videogames can be played through a gaming console or a computer. Players usually interact with them using a hand-held controller. Exergames consist of digital games in which its results are predominantly determined by the players’ physical effort, while partially / fully using their body as the controller. When combined with modern smartphones, these kinds of games present a high potential for ubiquitous scenarios due to the nature of the
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aforementioned devices. Ultimately, this can be viewed as a possible solution to promote healthy lifestyles and gaming beyond the couch.
1.1 Motivation
Many people, especially people that live in cities, lead a sedentary lifestyle. This originates health conditions that could be prevented or even minimized by exercising a few hours a day [1, 2, 3, and 4]. Unfortunately, many do not have the time to spend exercising, either because they are working late or because there are other matters that take that little time away. Another reason for this nonexistent exercising routine is the physical discomfort that comes associated with these particular kinds of activities [5].
Among other reasons, in their essence games are played for entertainment which often provides fun and enjoyment1. They can be played alone or with others cooperatively in teams or competing against one or many rivals. Player goals while playing vary from pure entertainment, to gaining rewards or achievements, depending whether the player is a casual one, an amateur one or even a professional one1. Some games can affect players, developing their agility and motor skills1, by means of exercise or by developing their mental prowess, by means of puzzle and number challenges. As such, games are supposed to have a fun factor associated with them and this fact engages people to play and have fun. Considering this, games that require physical effort have the potential to make physical activities more enjoyable, giving another dimension to simple exercising. Exergames do not take away all of the discomfort associated with physical activity but they bring a stimulus and engagement that makes these games perceived as more fun [4]. Exergames provide an excellent set of advantages that range from contributing to weight loss and physical health to facilitating social behavior / engagement [3, 4, 5, and 6]. For this particular instance, these games allow for new and captivating social experiences either by inducing competitive edge or cooperation between players [5, 7].
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1.2 Benefits of Exergaming
Exergames consist of digital games in which its results are predominantly determined by the players’ physical effort and provide the activity needed to counter sedentary lifestyles and the problems that originate from that lifestyle.
1.2.1 Physical Standpoint Effectiveness
Exergames capitalize on the virtues of both games and physical activity, by incorporating the fun factor of games in physical exertion. As such, exergames have a strong goal in granting players with some physical benefit [1, 2, 3, 4, and 8]. Research shows that in terms of energy expenditure2, exergames prevail over sedentary activities, effectively increasing said expenditure [8] when movement is involved. Also, factors like motivation, physical characteristics and experience contribute to the level of exertion [8]. Energy expenditure is difficult to measure [8] and can be defined as a combination of internal heat produced in living beings and their physical activity level2. It is commonly measured in Calories3 (thermochemical calorie energy unit) where 1C ≈ 4.184 kJ. However, research also indicates that there is a strong correlation between energy expenditure and heart rate independently of physical factors such as age, height and weight [8]. This is relevant because it simplifies the method of measurement for energy expenditure in studies of exergames and their physical effectiveness.
1.2.2 Cognitive Benefits
Regular physical activity grants cognitive benefits such as improvements in mood, concentration and memory [2, 4], as well as diminishing anxiety, stress and depression symptoms [2, 4]. Although studies regarding the cognitive benefits of exergames are limited, work comparing these benefits between a casual exergame, a standard treadmill exercise and a sedentary version of the same exergame proved that they can grant cognitive benefits on a temporary basis [4]. Casual exergames do not have a definite definition but they should be perceived as engaging, with limited time commitment to play and easy to establish. In that work, the casual exergame used the Kinect peripheral
2 http://en.wikipedia.org/wiki/Energy_balance_(biology)#Energy_expenditure 3 http://en.wikipedia.org/wiki/Calorie
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granting a natural interaction approach and allowing for an easy set up procedure. The sedentary version of the game could be played with a traditional mouse. Results state that cognitive benefits found on the casual exergame were comparable to exercising on the treadmill. However the sedentary version of the exergame did not achieve such benefits. Additionally, the results indicate that the affective state of players improved after playing the exergame. Another point relating to this work indicates that the exertion levels provided from the casual exergame and the exercise on the treadmill are similar but the first is perceived as more fun. This blends with what was stated in the previous section, as exergames aim to incorporate the fun factor associated with games and provide suitable energy expenditure when movement is involved [8].
1.3 Goals
The main objective of this work is:
To study persuasive features present in exergames and mobile exertion applications in general.
These features should contribute to motivate users to perform better [8] and may contribute to commercial success of these kinds of applications. Secondary objectives are:
Studying how the use of different modalities in ubiquitous scenarios can influence social behavior and user performance in exergames and mobile exertion applications. It is mainly intended to research how these aspects influence players to engage in these games (competing or working in cooperation to encourage one another) and how they contribute to single player behavior.
Studying how to promote these interactions is also an aim. Relevant aspects to be considered include current devices and their possible contribution to exergaming and the design of exergames related to target audiences, possible benefits and disadvantages.
Another objective of this work regards physical exertion data and its handling. Collecting physical exertion data in-game and carefully selecting which data should or not be shown to the player might encourage him to try harder. The
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same might happen if the game shows the other players data as well, in a group or community game.
The object of study will be an exergame related with jogging. Jogging4 is known to be a form of trotting or running at a slow pace which allows practitioners to increase their physical fitness and their life span4, decrease the effects of aging5 and benefits the cardiovascular system4. Jogging is typically a sport practiced outdoors by athletes and enthusiasts and shares a concept of an organized activity that promotes fitness and sociability. As such, the use of mobile devices is favorable, not only because of their practicality and proportions which matches well with a physical activity such as jogging, but also for their computational power. Current mobile devices grant us the possibility to track the location of a player and spatial distribute many players across virtual spaces by mapping their real world locations. They also allow for the use of input and output modalities such as audio, visual and touch-based modalities that can be used independently or in combination.
In sum, this works research goals are as follows:
RG1 [Primary] – Provide evidence that the use of persuasive cues affects players´ motivation
RG2 [Primary] – Research how persuasive social cues affect the players´ perceived competitive levels (e.g. stir competition or display cooperative play, resulting from the used persuasive social cues)
RG3 [Primary] – Understand how the delivery of exertion data contributes to influence players
RG4 [Secondary] – Study how the use of different feedback delivery modalities in ubiquitous scenarios can influence social engagement when using exertion systems
1.4 Contributions
This works´ major contribution will lie in the implementation of an exertion system (including a mobile exertion application) featuring two specific operating modes, the
4 http://en.wikipedia.org/wiki/Jogging
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“ghost” mode and the “live” mode. The first consists of a single player variation where the player can match his performance with a ‘ghost’ jogger. This ‘ghost’ can represent a previously recorded performance from the player or even from other players. This mode is inspired with similar features, normally present in video games of the racing genre where players drive a virtual car around a virtual track and when repeating the course are confronted with a ‘ghost’ virtual opponent that represents the players´ previous performance.
The aims of the study with the ghost mode center around its influence on the player, possibly persuading the player to achieve better performances and gain incentive to keep playing and exercising. The “live” mode consists of a broadcast function that allows players to share their workout sessions with friends who play the role of spectators that can interact with the player in a real time fashion. Studying impact and influence on social interaction and respective player performance is the main goal regarding this mode. This contemplates the use of a communication channel that should make joggers engage in competitive (e.g. by messaging ‘trash-talk’ to other joggers) or cooperative (e.g. by messaging incentive lines to raise morale) play.
Another important contribution relates to the creation and proposal of a design space correlating all mobile exertion application related variables with persuasion factors. The aim of this design space is to consolidate the existing knowledge regarding persuasion and mobile exertion applications into a single design space, providing a broad enough coverage of the dimensions related to persuasion techniques employed in applications of the genre. The channels used to convey that persuasion, the instant the persuasive cue is created and delivered to the interested parties and the actors involved in the process are specially emphasized.
1.5 Planning
1.5.1 Schedule
Review of the related work
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An extensive investigation of the related work regarding exergames and mobile exertion applications which is the object of investigation was compiled. The purpose of this investigation was to achieve a satisfactory level of familiarization with all aspects regarding the theme under investigation, including technology and methodology applicable to the work in progress.
Writing of the preliminary report
T2: from 01-11-2012 to 31-11-2012
A report containing all gathered information about the projects´ subject was written. In it is described the state of the art in the area of exergames and mobile exertion applications and the projects´ goals, challenges and expectations. Also any work phase already accomplished was included.
Solution development
T3: from 01-12-2012 to 31-07-2013
A prototype of the Exodus exertion system was programmed. This prototype featured all the designed features. All system components were developed in this period.
Planning and execution of experiments
T4: from 01-08-2013 to 15-09-2013
Establishment of a series of experiences and trials using the implemented prototype of the Exodus exertion system was performed. These tests were meant to verify whether the implemented features achieve the projects purpose of study.
Writing of the Masters´ Thesis
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The masters´ thesis document was written, containing detailed description of all development phases of the project, examination of the results obtained and some critical evaluation of the overall work accomplished.
1.6 Document Structure
This document is organized as follows:
Chapter 2 – Related Work
This chapter will describe the synthesis of the whole process of research on persuasion factors and design guidelines of exergames and mobile exertion applications.
Chapter 3 – A Design Space for Persuasive Mobile Exertion Applications
This chapter will elaborate on a survey regarding mobile exertion applications, specifically how they are used and perceived by people. Also, resulting from the survey and related literature, a design space accommodating all persuasive variables regarding these kinds of applications is introduced.
Chapter 4 – ExodUS
This chapter will present the elaborated work, detailing the developed mobile exertion application system.
Chapter 5 – Experimentation with ExodUS
This chapter will focus an experiment devised for making use of the developed solution.
Chapter 6 – Conclusions & Future Work
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Chapter 2
Related Work
This chapter will expand upon persuasion factors linked to exergames. The study will focus on persuasion techniques and instruments that can potentially influence players to achieve better performances and higher motivation levels.
Being that exergames are the central point in this work, all work related to the study, design and development of exergames, including persuasion factors employed with exergames, will be warranted in the next subchapters.
Finally, this chapter will conclude with an extended overview of Mobile Exertion Applications (from here forth referred to as MEA), bridging the existing conceptual designs and techniques with our work.
2.1 Persuasion Definition
People are usually confronted by persuasion in their lives. Advertisements, politics, mass media, among other areas, are always present in our everyday lives as a way to influence us, or rather convince us of something. This is exactly what persuasions´ goal is: to convince the target audience to internalize the persuasive argument and adopt this new attitude as a part of their core belief system6. Persuasion can result in positive outcomes for the persuasion target (e.g. public campaigns that urge people to quit smoking or to recycle their garbage), but they might also not favor them (e.g. a pushy salesman trying to sell you a car)7. Psychologists perceive persuasion as a:
6 http://psychology.about.com/od/socialpsychology/a/persuasiontech.htm 7 http://psychology.about.com/od/socialinfluence/f/what-is-persuasion.htm
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“Symbolic process in which communicators try to convince other people to change their attitudes or behaviors regarding an issue through the transmission of a message in an atmosphere of free choice” [25]
Persuasion exists since ancient times and has evolved since then as well, being nowadays characterized by the massive number of persuasive messages we encounter daily (e.g. the number of commercials and advertisements we are faced with every day), the speed in which these messages are delivered (e.g. through the Internet, television, etc.), the existence of businesses which work solely around persuasive messages (e.g. public relations companies or marketing firms), the refined subtlety employed and the complexity level of the persuasive cues (e.g. careful selection of the persuasive medium and message in order to stand out from the more diverse choices target audiences are allowed to choose from).
2.2 Persuasion Factors
The hypothesis to use technology to change peoples´ behavior is the core belief of persuasion factors incorporated into exergames and games alike. Persuasion techniques aim to influence the players to adopt certain strategies and actions, coping with an intended target behavior. To understand this topic, we need to consider how technology can influence a person and how behavior works.
2.2.1 Contingencies and Behavior
Persuasion techniques have a pre-defined purpose, a target behavior to which the players should adopt. Understanding behavior is essential when designing persuasive techniques. Prior reading divides exergame benefits in two different dimensions, one for psychological outcomes and another for physiological outcomes. The second deals with aspects relative to exertion and physical activity. The first, however, deals mainly with abstract variables such as enjoyment and engagement. This last one gains a specific importance for exergames, since it is directly responsible for its success [8]. Examples like the Yourself! Fitness8,9,10 exergame can provide insight on this issue. Although this
8 http://www.healthgamers.com/2010/exergaming/the-history-of-exergames/ 9 http://gadgets.boingboing.net/2008/05/15/from-atari-joyboard.html
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game provided high quality physical routines it couldn´t match the Wii Fits´6,7,8,11,12 success, because it was not perceived as fun and engaging7,8. This leads designers to seek an understanding of player behavior, which in turn relates to principles and contingencies that affect players´ emotional states and likelihood of adoption and maintenance of the games´ required physical activity [9].
Contingencies are present in ordinary games, not just exergames. In order to perceive them a behavior needs to occur. Contingencies are composed of three main elements in a linear relationship. These elements are antecedents, consequences and behavior. Their relationship translates into the following: [9]
Figure 1 – Three-term contingency relationship
This is a temporal relationship that shapes simple or complex behavior. Antecedents are essentially stimuli that precede a behavior, or rather leads to a specific behavior. In games, these stimuli can affect the players’ emotional state and the adoption and maintenance of game play. Consequences are the result of behavior and also of the antecedents that preceded the behavior, essentially being the stimuli the follows behavior. Analyzing this relationship we can discern that antecedents and consequences help in shaping particular behaviors and this is the very aim of persuasion techniques. Thus persuading using antecedents, signaling target behavior requirements (e.g. compel players to learn and perform a certain move or play; push for an imitation or a match of a certain behavior model), and consequences, decreasing the probability of behavior (e.g. applying penalties) or increasing the probability of behavior (e.g. positive or negative reinforcement), translate into persuasion techniques´ inner functioning, coding specific antecedent and consequence elements incorporated within a game. A specific example of this relationship within an exergame would be playing
10 http://www.todaysfitnesstrainer.com/making-exercise-fun-the-evolution-exergaming-part-two/ 11 http://en.wikipedia.org/wiki/Wii_Fit
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Dance Dance Revolution6,7,13. With this exergame, when a player steps and hits one of the four arrows present in the respective dance platform (behavior), a stimuli may be presented by means of an audio feedback mechanism or a graphical representation (consequence) informing the player of the success or failure in the task executed. One behavior can result in more than one consequence [9], for instance, if both an audio feedback mechanism and a graphical representation occur then the behavior resulted in two consequences instead of just one. Antecedents complete the three-term contingency relationship and can be identified when, on the games´ on-screen interface the virtual arrows scrolled upwards approach the “step zone” (antecedent). This translates as a visual stimuli indicating that the player should step on the corresponding platform arrow (behavior). Equally to consequences, antecedents can also be of multiple instances. Finally, behavior is an inherent part of games and exergames (e.g. running, jumping, dancing…), making up the players´ responses to the game and though interactions with several consistencies lead to a change in dimensions such as rate and duration, among others [9]. Games usually influence players´ behavior by permitting certain qualities of behavior to affect it. Table 1 depicts these qualities (based on the research presented in [9]).
Table 1 - Behavior Qualities and their effects
Quality of
Behavior Effect
Topography Form of the behavior (e.g. repertoire of paddle movements in a Table Tennis game)
Frequency Number of times a behavior occurs Rate Frequency within a specified period
Intensity Strength or force applied in the execution of a behavior Latency Time between a signal for response and the resulting response
Duration Time from the onset to the offset of the response without interruption
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The three-term contingency relationship can also reinforce behavior [9]. This reinforcement (intermittent or continuous) occurs based on the aforementioned qualities of behavior.
“Within each game, multiple levels can exist and each level presents multiple types of stimuli, rules, and behavioral requirements. Game designers program these stimuli, their functional effects, and the behavioral requirements for specific purposes, with or without knowledge of their influence on adoption and maintenance of game play and emotional states.” [9]
From this topic we learn that contingencies, the stimuli prior to and following behavior, affect behavior. To reinforce this, carefully looking into the case of casinos´ slot machines will uncover how contingencies can persuade players. These machines are designed to influence players to adopt and continue their gambling behavior [9]. These techniques can be used in order to increase success probability for exergames (and games alike).
2.2.2 Persuasive Models and Technology
Prior reading indicates that behavior and contingencies are intrinsically related with persuasion elements. Behavior often leads to social interaction. Persuasive elements in computer systems have originated from the belief that people often respond to computers as though they are living beings [10]. This fact makes computer systems suitable to play the role of a persuasive social actor, capable of creating and maintaining a relationship with its users. An example would be the Tamagotchi14, a handheld digital pet simulation game, which consisted in the existence of a digital creature that could grow, developing depending on the care provided by the player. This gameplay lead players to interact with the digital pets, as strongly as if they were “real” pets. Some other examples of such cues applied to exergames exist, such as the use of a virtual trainer character in the Yourself! Fitness6,7,8 exergame, an exergame which operated with the sole purpose of guiding the user to perform an exercising routine to improve their shape with the guidance of MAYA, a virtual trainer character that was always
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present on-screen and that served as the proxy between the program and the user. The use of such character implies that the game designers relied, on some level, on physical (3D human model) and social role (role playing the physical instructor / teacher authority role) cues. Another example is the successful Wii Fit exergame6,7,8,9,10 and its use of cute virtual characters that take on social roles of opponents and manifest other persuasive social cues.
Persuasive Social Actors
Foggs´ work suggests that when perceived as social actors, computer products can leverage principals of social influence to motivate and persuade [10]. Combined with the way people respond to computers, social influences and dynamics can play a significant role in persuasion factors applied to technological means, particularly with games. As such, peer pressure and social comparison (among others) become a strong motivator for players / users of such systems. Fogg proposed five types of primary social cues appliable to computer systems: [10]
Table 2 – Foggs´ Primary Types of Social Cues
Social Cue Example of an element regarding the Social Cue
Physical Face, eyes, body, movement
Psychological Preferences, humor, personality, feelings, empathy Language Interactive language use, spoken language, language recognition
Social Dynamics
Turn taking, cooperation, praise for good work, answering questions, reciprocity
Social Roles Doctor, teammate, opponent, teacher, pet, guide
Persuading using physical cues aims to prompt social presence through physical characteristics. Physical attractiveness tends to have a considerable impact on social influence [10]. High-persuasive tasks are often fulfilled by more attractive people (e.g. salesman, advertising or spokesman), which confirms that more attractive people tend to
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be more persuasive than unattractive people. Mapping this to technology, we can assume that technology that is visually attractive is likely to be more persuasive than an unattractive one.
Although physical cues can prompt social presence this is not necessarily required, as computer systems can also convey it without using physical cues altogether [10]. Psychological cues are intrinsically related with emotions and personality concepts. Products that aim to persuade through psychological cues should try to convey simple cues such as empathy and emotion or / and complex cues that portray personality [10] (e.g. a computer that keeps crashing may convey a personality of being uncooperative). Psychology studies indicate that people we think are similar to us in personality, preferences or in other characteristics can persuade us more easily than those we deem as not being similar to us [10]. This research provided insight on this matter, concluding that similarity between computers and users (both with dominant or submissive personalities) can influence, persuasion wise. Also, the notion of group affiliation (e.g. teammates) contributes to persuasion through psychological cues.
Language also acts as a powerful tool with persuasion in mind. Delivering feedback cues, whether they are written text or audio pieces, using spoken language can influence people to adopt certain behavior (e.g. e-commerce sites use certain language patterns to persuade users to keep buying). This approach often empowers the systems with distinct personalities which lead to achieving goals such as acquiring and maintaining users. This usage of language coupled with the recurring use of praise also has a strong impact on users´ motivation and openness. When praised, people often react more positively, resulting in better mood, interactions and attachment to the used systems [10].
Culture influences behavior, as people tend to adopt certain behavior patterns that are considered as a norm within their culture. This is also valid for social interaction (e.g. shaking hands as a way of greeting). Modeling social dynamics is another way to persuade using technology [10]. A successful application of this type of persuasive cue are e-commerce sites that model traditional shopping social dynamics “behaving” just as a traditional clerk would. Systems´ can adopt persistent approaches, as well as exert peer pressure which ultimately should influence users. A powerful social dynamic is based on the principle of reciprocity, which states that favors should be returned. Foggs´ work [10] proves that this principle is also replicated when interacting with computers,
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meaning that if people find the systems´ feedback useful they will, most likely, try to reciprocate the favor.
Lastly, persuading recurring to social roles can lead to compelling interactions between systems and its´ users. The Tamagotchi12 is a good example of this persuasion cue, as the game played the role of a pet which compelled users to take care of it as a real, live pet. The role of a pet is good enough, persuasion wise, when the target audience is composed of a young population. Social figures of authority such as police officer, judges, teachers or doctors have enhanced powers of persuasion as people will associate them with intelligence and influence. Some applications could also benefit from other type of social role persuasion, such as the role of a teammate / friend or opponent for games.
Careful handling of social cues is needed if designers want their systems to be effective in persuasion [10]. The viability of persuasive social actors is always related with the target audience and their specifics. Areas such as games and entertainment are a prime target for the use of such actors because players are generally a target audience which is more willing to accept and perhaps adopt the kind of social cues these actors provide. Designers should also search for the best possible quality and repetition of a social cue, to avoid risking players to become annoyed or even angry.
“When is it appropriate to make the social quality of the product more explicit? In general, I believe it’s appropriate to enhance social cues in leisure, entertainment, and educational products (smart toys, video games, kids’ learning applications). Users of such applications are more likely to indulge, accept, and perhaps even embrace an explicit cyber social actor — either embodied or not.” [10]
Persuasive Technology Design
Even though much work has been done regarding the use of persuasive factors in technology, persuasive technologies are a relatively new reality in peoples´ lives and this reality is changing with the advancing years, with many opportunities for the use of this kind of technology arousing [11]. However, its design process has a big problem as it mostly faces failure [11]. Work addressing this issue [11], proposes a process consisting of eight basic steps that should be performed by design teams wishing to develop persuasive technology. This method applies to the early stages of development of such technologies and aims to solve the failure of most of these projects, whose most
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likely cause has been identified to be because design teams have a goal that is too ambitious or lack in experience to develop this kind of technology. The process is described as follows: [58]
Figure 2 – Persuasive Technology Design in Eight-Steps
The first four steps are inextricably linked and might not necessarily be followed in the order presented in the figure above. They are nevertheless essential to the eventual success of the project. The first step advises to choose an appropriate behavior for change and is the most important step. This behavior should be the easiest and smallest relevant behavior. The second step recommends choosing an easy target audience, meaning an audience that has demonstrated a desire to change the behavior targeted.
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These kinds of projects usually fail, especially in its early stages, with selection of a wrong audience [11]. The third step emphasizes on the issue of determining the reasons which prevent the targeted audience from performing the targeted behavior. These reasons normally fall under one of three categories, them being the lack of motivation (e.g. to perform a physical activity), the lack of ability (e.g. not enough fitness level to perform a physical activity with a certain intensity that requires a minimum fitness level) or the absence of a well-timed trigger to perform the response (e.g. an audio feedback mechanism alerting a jogger to dash during a fixed period). The fourth step pertains to the choice of a familiar (in relation to the targeted audience) and adequate (in relation to the targeted behavior) transmission channel, technology wise. The fifth step states that the design team should search for relevant instances from companies which are succeeding because their solutions are likely to be effective or in other words, the designers should find successful examples relevant to their project (having in consideration the decisions made from the previous four steps). A common issue regarding this task is that information pertaining these examples might not be accessible (e.g. companies generally don’t share data with outsiders) so making educated guesses is a sensible approach [11] to overcome this problem. The sixth step relates to the old concept of ‘no need to reinvent the wheel’, meaning that after obtaining some successful examples imitating them is a reliable method to create the projects´ persuasive technology. Identifying and adapting existing solutions grants benefits, time wise and reliability wise, but to conduct this step, insight is required. The ability to explore an existing successful example and extract whatever key components that make up its effective success is the challenge. Real innovations, like all activities that foresee the creation of something, require a solid foundation, which can be built recurring to these “imitations”. The seventh step expresses the need to perform tests on the persuasive experiences rapidly and repeatedly. Undergoing a series of small, rapid tests is better than doing a big test [11] and these tests are not meant to be scientific experiments but rather quick trials that allow for prototyping and to test peoples´ reactions by measuring behavior. Each test, whether it is successful or not, will result in gain of more insight into rapid testing and what´s likely to work next time. The final eighth step can be considered once a small scale success is achieved. This moment defines a milestone and the project can then be expanded. This expansion can either aim for a new audience, less adoptive to the behavior and more difficult cases, or it can aim to target a tougher behavior. This expansion should only vary one or two attributes form the previous
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success and should be systematic. This step can also be considered for bigger tests, like academic research, as a starting point [11], unlike the tests performed in the seventh step.
2.2.3 Persuasion Approach
For this work, persuasion is a tool that should be used to achieve our research goals. Persuasion techniques are used to mold and make players adopt specific behaviors which in our case is to increase motivation while achieving better performances and engaging in social interactions while playing. Programming contingencies to target such behaviors is encouraged as they help shape our target behavior. Antecedent stimuli can me conveyed recurring to a set of features ranging from the use of different modalities for feedback messages to providing tutorials for the players (e.g. teaching the correct way to run or breathe during the exertion activity). Consequence stimuli can either be achieved through feedback messages, in-game challenges and reward / penalty schemes. Social interaction plays a part in this work, as some contingencies can originate from the use of persuasive social cues. Ultimately, the design of our product will try to somewhat follow the eight-step design process proposed by Fogg [11], both for the research phase and the testing phase.
2.3 Exergame Design
Following persuasion factors and their specifics, we need to address their standing within the design considerations proposed for exergames. Aspects relating to persuasion factors, social play, interfaces and audience specifics should be regarded in exergames´ design approaches.
2.3.1 Design Considerations
Social Design
It is perceived that, the design of exergames is easier to understand when we associate them with sports [12], since exergames provide the same kind of experiences, benefits and disadvantages that sports aim to provide [5, 13]. Sports normally involve physical exertion and comprise activities that obey a set of rules and oblige practitioners
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to acquire skills in order to be successful. These activities can originate different behaviors and physical changes to its´ practitioners depending on the rules and goals of gameplay. Sport players develop their physiques as they undergo training sessions gaining skills in the process and engage in social interactions such as competing and playing against others or cooperatively play with others in a team [12].
Some work suggests that movement in itself can be a trigger to emotional responses and increase social ties between players [14]. Results hint at an increase in social interaction when movement is present. Also, the use of a motion-based input device increases social interaction [15].
Work regarding networked exergames and their influence on social play as been done [3, 13] and suggest that exergames can facilitate social experiences within these games. In regard to that work, a sport, Table Tennis, was augmented through the use of telecommunication technologies. This helps to validate the claim that exergames can be is easier to understand when we associate them with sports [12]. The results regarding this work indicate various pointers towards social interaction. The focus of the gameplay is shifted from the virtual world to the physical space, since most of the attention of the players is directed at the events occurring in the real world physical space. As such, this shift in focus introduces several aspects that allow for the performance of unexpected behaviors that don´t occur in traditional games or are more difficult to perform (which become new persuasion opportunities). Also, social play interactions can be affected by previous relations between players [13].
Designing for Specific Audiences
Player needs are different when taking in consideration aspects like age and physical condition. Usually, games that require physical activity are associated with a young target audience, boasting their player skills and as such, for their testing it is also usual for children or adolescents to participate in testing [8]. For older adults [6], problems pertaining illness, lack in cognitive ability (e.g. deficit in attention, memory loss) and diminished physical attributes (e.g. poor strength, low energy, less muscle mass) should to be addressed and because common exergames are designed in a way that does not address these issues, they result in elderly players´ exposure to injuries. For these cases and for overall exergaming systems, using adaptive interaction paradigms seems to be benefic in order to accommodate to players individual
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differences [6]. Exergaming has been appointed as a way to improve existing rehabilitation programs and grant other health benefits [4, 6, and 16]. From other works we can assess that the leading consumer exergaming systems have sufficient speed and accuracy for such tasks [16].
2.3.2 Persuasive Driven Design
The study of exergames has led to the creation of some frameworks regarding the design process of exergames. These frameworks give valuable insight on how to create successful exergames, accounting for generic game related points, including persuasive factors.
Dual Flow Model
Exergames aim to provide two goals: incentive and physical benefit. However these goals are tough to obtain simultaneously [8]. Incentive should be perceived as the capability to retain a sufficient level of interest from the players and motivate them to keep playing. As such, incentive is difficult to quantify given that every single player has its own uniqueness, be it in preferences, physical attributes or how experiences are perceived. But incentive is an integral part of the exergaming concept because it relates to the fun factor associated with games1, which in turn counters the issue of the physical discomfort associated with physical activity [5]. It also relates with persuasive factors as it blends with the previously studied concepts of persuasive social cues and the use of contingencies to persuade. These aspects tie with the factors that make exergames succeed such as frequency [8, 17], enjoyment1 and attractiveness [17, 18]. Relating to frequency, players expect to see results which should only show when the game is played for an extended period of time thus requiring a firm motivation to continue to play [8]. Attractiveness deals with the “flow” concept [17, 18], originally proposed by Csikszentmihalyi´s work which revolves around the level of absorption on the activity being performed, focus of awareness and actions/skills taken [19, 20]. The concept is applied in various works, including with games [21]. A modified version of the concept directed at video games treat the “flow” as “game flow” and lists a few characteristics which are commonly identifiable in games, and not just exergames, that contribute to their attractiveness and enjoyment.
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During the design phase of a game, some characteristics can be explicitly built-in the game in order to affect the player state [17]. Attractiveness can also be influenced by the input device features [17], as in order for a player to gain a sense of immersion while playing, their concentration needs to be focused and can either be set upon the game itself or on the input device being used. Physical benefit [8, 17, and 18] should be perceived as the effectiveness of the exercise benefits provided to the players. For the successful design of exergames, other aspects have to be taken into account such as the fact that players´ fitness is not static and the ability to deal with the physical exercise and its intensity, which also varies [17]. These aspects are responsible for the existence of challenge and skill and contrary to incentive, can be measured.
Based on the previously described aspects of attractiveness (incentive) and physical benefit, the Dual Flow Model [17, 18] models both with the aim to deliver exergames that meet a required level of exercise in order to maximize the benefits provide by physical exercise while maintaining the activity interesting and engaging.
“One of the constructs of flow is the balance between perceived skills and perceived challenge. An activity needs to be neither too easy nor too difficult.” [18]
Balancing players´ perceived skill versus perceived challenge makes a psychological model, related to gameplay and aspects of the game where four different states can be determined. Players lacking in both skill and challenge experience a state of apathy, while players lacking in one of these variables experience boredom (skill > challenge) or anxiety (skill < challenge). Likewise, balancing intensity versus fitness makes a physiological model, related to exercise and physical activity where, again, four states can be determined. Players lacking in both intensity and fitness experience a state where no benefit is achieved whereas players with a high level of intensity and low level of fitness experience failure (inability to continue the physical activity) and players with low level of intensity and high level of fitness experience deterioration (fitness level decrease). For both these models, the ideal state is the ‘flow’ state where both, skill / challenge for the psychological model and intensity / fitness for the physiological model, are high resulting in more engagement and better fitness through continued exercise [17, 18].
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Figure 3 – The Dual Flow Model for exergaming
An exergame created with the Dual Flow Model in mind [18], shows that it is possible to deliver the necessary level of exercise across players, maintaining a good heart rate control system. The fact that heart rate seems to be essential to achieve the models´ purpose is expected [8]. Furthermore, from this work we can identify the need to create control systems for both intensity and challenge and a few framework components [18]. These components are responsible for maintaining player performance history records and planned exercise, as well as gameplay and feedback methods.
