Experience with a 3D Kinect Exergame for Elderly

Ellen Brox

, Gunn Evertsen

, Heidi Åsheim-Olsen

, Santiago Hors-Fraile

and James Browne

Norut (Northern Research Institute), P.o.box 6434, 9294 Tromsø, Norway

Norwegian Centre for Integrated care and Telemedicine, P.o. box 35, 9038 Tromsø, Norway

Keywords: Exergames, Serious Games, Senior Gamers, User Centred Design, Elderly, Kinect, 3D.

Abstract: Physical activity is important for all, but for the elderly balance and sufficient strength is vital to function in

daily life. It can be difficult for all of us to find motivation to exercise at home, and seniors are no

exception. We have experienced that exergaming can be motivational for elderly since it is fun, but most

commercial games are not optimal for elderly due to speed, required movements, colours, the amount of

information, etc. In a project we designed an exergame specifically with the elderly in mind based on user

requirements both for specific needs for elderly, for games in general and for good exercises. A first

prototype of an online 3D exergame using Kinect

was developed and tested on a group of six seniors.

Kinect

was chosen since after our experience users in the target group can handle exergaming with this

technology, and also it is possible to control that the exercises are performed correctly. Our aim was to

investigate how seniors would react to a 3D first person environment before we continued the development.

A user centred method was applied in the design and development, and the user test is part of that. The

results are encouraging.

1 INTRODUCTION

Physical activity is important at all ages, but elderly

often get into a vicious circle where fear of falling

leads to less physical activity and reduced strength

and balance, which again lead to a greater risk of

falling. Falls are among the most common reasons

for medical intervention in the old (de Bruin,

Schoene, Pichierri, Smith, 2010). To motivate to do

physical activity in a fun way, some senior centres

and old people’s homes are using exergames (Brox,

Luque, Evertsen and Hernandez, 2011).

Exergames is a term used for video games that

are also a form of exercise, and it relies on

technology that tracks body movement or reaction.

Particularly two platforms are being used:

Nintendo® Wii

and Kinect

for Xbox. The

exergames made for these platforms are made for a

younger audience, and there are several obstacles for

elderly users. Speed can be a problem (Wollersheim

et al, 2010, Theng et al, 2009), the games can be too

difficult (Anderson et al., 2010), or the games do not

satisfy specific needs of elderly regarding for

instance eyesight, fine motoric skills, the need for

less information and more time to get an overview,

etc. (Brox et al., 2011, Gerling et al., 2010). Studies

show that exergames can be used for balance and

physical exercises (Wollersheim et al, 2010, Rendon

et al, 2012, Chao et al, 2013, Williams et al 2010,

Billis et al, 2010, Jung et al, 2009, Theng et al,

2009). Also (Larsen et al, 2013) made a review

study of controlled trials where six out of seven

papers showed a positive effect of the intervention

with elderly using exergames.

Our aim is thus to make an exergame for elderly

that gives good exercises that are beneficial for the

elderly and, at the same time is both suitable for the

target group and fun to play. The game must be easy

to use for the target audience but, at the same time

give users enough challenge to want them play

several times. According to our user tests seniors

enjoy both some of the commercial Nintendo®

Wii

and Kinect

exergames in tests we have

performed but, we have also experienced that many

have problems of the aforementioned types.

Particularly it can be difficult to understand what the

game is about and be able to notice information that

is popping up for instance in the corners.

Playing an exergame can be a way of motivating

elderly to exercise more, since this is perceived both

as fun and useful by the elderly that we have talked

to during the project.

231

Brox E., Evertsen G., Åaheim-Olsen H., Hors-Fraile S. and Browne J..

Experience with a 3D Kinect Exergame for Elderly.

DOI: 10.5220/0005165602310238

In Proceedings of the International Conference on Health Informatics (HEALTHINF-2015), pages 231-238

ISBN: 978-989-758-068-0

 2015 SCITEPRESS (Science and Technology Publications, Lda.)

2 METHODS

User centred design was used in the development.

End users participated in the requirement phase, as

well as in the design and the development phases of

the first prototype. Typically a mixed method is used

in user centred design.

2.1 User Requirements

The first step in the game design was to collect basic

requirements for our target group. We started with

collecting requirements from literature, and together

with our own experiences this forms the background

for the game design. In the project we have

experience in playing commercial Nintendo® Wii

with seniors, and, in addition we have also had two

groups of old seniors trying both Wii

and

Kinect

. The movements of the game story were

accepted by the physiotherapist in the project. Via

observations, group discussions and interviews,

these experiences also contribute to the

requirements.

2.2 Design and First Tests

A game story was developed that took into account

the requirements and exercises that are suitable for

the target group. The story was discussed and

adjusted in the project group, and a first version of a

game was designed and developed.

Early versions, also multiplayer, were tested on

senior colleagues (60 and above) since the versions

were too unstable to test on even older persons. A

group of six seniors with an average age of 80 were

then recruited to test an early demo in single player

mode. They gave valuable feedback, particularly on

the colours and graphical layout. Several graphical

elements were changed before the lab trials.

2.3 Lab Trials

The same six seniors later participated in a lab trial

where they played the first prototype consisting of

three mini-games. The game was also this time

played in single player mode. Only two had tried

Kinect

before (in our first test), but all of the

participants had been playing Nintendo® Wii

games. Since the main goal was to test the gaming

concept, researchers handled the technology and the

participants only had to use their hand and body

movements to give input to the game.

The players would come one by one into the test

lab. First a researcher explained the gameplay to the

participant, and then the play started. The players

also got some instructions during the gameplay if

they had problems.

Ideally, the Kinect

should be calibrated for

each user since the body is used for input. This

calibration includes the height of the person and the

length of the arms. This means that each user

calibrate and adapt to the game before they play, and

possibly also create personal user profiles for later

use. This was not done for our game; instead it was

developed to not be very sensitive. Still this could

mean that the gameplay was biased and would be

easier for some than for others. Our game tracked

the users’ movement ranges: how far they put their

hands above their heads, how close their knees were

to their hips in a vertical axis, etc. These parameters

were not registered or analyzed; they were only used

to perform actions within the exergame.

2.4 Data Collection

All participants signed an informed consent before

the trials. They also filled in a questionnaire with

background information such as age, gender, game

experience, exercise habits, etc. The study was

accepted by the Norwegian Social Science Data

Service.

During the lab test researchers filled in an

observation protocol for each of the players. After

the testing the participants went through a structured

interview where questionnaires regarding their

experience were filled in with the help of the

researchers.

When the lab test was over we had a group

discussion where all six players were asked about

the game and how they felt when they played.

3 THE USERS

The participants were recruited at a senior centre

offering weekly Nintendo® Wii

exergaming for

seniors. The members of the group that was playing

were informed about our work and were first invited

to participate in a pre-trial, then a lab trial with a

slightly moderated version. The users participated at

their own will and there were no health care

personnel involved in this phase.

We only managed to recruit six users for the lab

trial. They were between 76 and 83 years old, two

men and four women.

All of the participants had a mobile phone, all of

them used it for calling, five for messages, four used

the clock function and the calendar. None of them

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were using the phone on Internet. Four in the group

had a PC but only three were using it, two of them

several times per week, the latter more seldom. The

PCs were used for e-mail, paying bills, reading local

news, and one was on Facebook.

4 BASIC USER REQUIREMENTS

Basic user requirements when designing games for

elderly were identified. For instance, seniors we

have talked to say that they want to feel that the

game is good for their health, so the game must be

designed with exercises that are useful for their

balance, flexibility, strength or endurance. For the

exergame to be a game, it should also have some

challenges and be fun to play.

For this target group it is also important that it is

playable with a variety of physical and cognitive

ailments. For instance the players should be able to

play in their own pace, so the speed should be

adjustable. The game should also allow the players

to take pauses, and there should be different levels

for people with varied physical abilities. The game

should of course also be safe to play.

Also there must not be too much information at

the time, and there should only be one focus of

attention, meaning that the players shall be able to

play without having to consider extra information

for instance in screen corners. The graphics should

be designed so that elements are big and clearly

visible. In addition we wanted a game that could

enable communication and social contact, so that it

can be played together from different locations.

5 THE GAME

5.1 AntiqueHunt - the Game Story

A game story including both social elements and

selected exercises was made. In the game the seniors

were supposed to collect antiques in an old house,

and different rooms give different exercises, for

instance stretch to get items from a shelf, bend down

to pick up items from a chest, walk up the stairs to

the attic, etc. The first scene was also supposed to

work as a lobby where players can meet each other

if they play P

The players meet outside in a garden. In the

multiplayer mode they can see each other and hug

and wave at each other. A key is hidden somewhere.

The players have to turn around and look for it, and

then walk up to it. When the first person reaches the

key, the house is opened and the players will find

themselves in the next scene which is a room in the

house. They will no longer see other players. One

reason is that this makes it easier to focus on the

gameplay. Another reason is that some might find it

embarrassing if others see how they perform.

The players will move from room to room to

collect items. In one room they are supposed to

stretch to collect things from shelves, in another to

bend down to pick items out of a chest, and in yet

another room they are supposed to stand on a chair

to stretch to take pictures from the wall. The story

also contains stairs where they can climb to the attic.

When the players have gone through all the rooms,

they meet again in the garden to see what they have

gathered and get their game rewards. They again

have to look around to find the collected items and

walk up to them to get an overview of what they

have gathered – and get the game rewards.

The game shall be customizable, meaning that

the number of scenes (rooms) and the duration or

number of items can be adjusted to each (group of)

player(s). The game proceeds at the speed of the

players. For instance when they are looking for the

key, they can take the time they need, and when they

look for antiques in the room, a new item will not

appear until the previous is taken.

5.2 Game Design and Platform

The game was designed according to a

physiotherapist’s recommendations. The elderly first

perform "warm up" exercises where they do soft

exercises like hugging and walking. Then there are

exercises for stretching and bending their body.

Finally, there is a cool down phase where they can

discuss how they felt and exchange their experience

in the game.

From a technological point of view, the game

was developed using a full JavaScript stack. To store

the user's information, such as their name, their

previous scores and what group they were prescribed

to play with, we needed a database. To keep in line

with the JavaScript stack we used MongoDB, a

cross-platform, document-oriented, NoSQL

database.

We used Node.js as the server side platform

along with SocketIO as a method to network the

data. Node.js uses an event-driven, non-blocking I/O

model that makes it lightweight and efficient, perfect

for data-intensive real-time applications that run

across distributed devices, making it perfect for

streaming real time joint data to multiple clients. The

Experiencewitha3DKinectExergameforElderly

233

rendering of the data was handled in any WebGL

capable web browser by a WebGL wrapper called

Three.js, which was then displayed via HTML5.

These coupled with the Kinect SDK and OpenNI to

gather the joint data of the users made up the full list

of the main technologies used.

Figure 1: The start pose.

5.3 Game Poses

To start the game, both arms should be lifted as

shown in figure 1. A pause pose is implemented, and

this is the standard pause pose for Kinect

– i.e. the

arm is held in 45 degrees from the body. This is

shown in figure 2.

Figure 2: The pause pose.

To turn to the left, the player has to lift the left

arm, and to turn right the player has to lift the right

arm. To move forwards, the player has to step in

place. To grab items coming towards them from the

ceiling, they have to lift both arms.

5.4 The First Demo and Prototype

A first demo was made and tested on a user group.

The demo was pretty rudimentary, but enabled us to

try out the concept on end users as part of a user

centred design and development. This demo

consisted of three scenes: the first was in the garden

where the players should find the key, the second

was in a room where items were collected from

above the player and, the third was back in the

garden, but this time the players had to search for the

items that they had collected and walk up to them.

The game was played in single player mode, since

we first wanted to capture the reactions on playing a

3D game, and the main game concepts. The game

requires correct movements, for instance items can

only be collected if the arms are raised. It is possible

to register game activities, but this was not done in

the first prototype.

Graphical elements of this first demo were

changed after a session with seniors. Please see

figure 3 that shows colour and texture of the lawn,

figure 4 shows that we made changes in the room

and, figure 5 shows the colour and size of the key

and the avatar. Still the graphics will need to be

changed in a later version. After the changes were

done, we had a lab test with six users.

Figure 3: Grass on the lawn before (top) and after changes.

The dark colour and texture of the grass made it hard for

the elderly to see, so we made the grass lighter and with

less texture.

5.5 The Lab Test Setup

The lab test was performed in the premises of the

researchers. Three rooms were set up for the lab test:

1. A lab where the tests were performed. 

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2. An interview room where one researcher would

be together with the user who had just

performed the test



3. A waiting room with coffee available for those

who either waited for their turn or were finished

with the trial.

Figure 4: The walls in the room before (top) and after

changes. Also here the users found the pattern too dark

and disturbing.

Figure 5: The avatar and the key in the lab test version.

Also the lab test was performed in single player

mode since adding remote players would make the

game more confusing, and we wanted to test how

they reacted to the 3D game environment.

One researcher was taking care of the technology

for all the participants in the trial. One researcher

would watch and fill in the observation protocol.

6 RESULTS

All six got help to select player and start the game

and all played the game to the end without any other

help than oral guidance. The users did not operate

any menu buttons in this first prototype, all

gameplay and interactions were via poses and body

movements. The main results of the trial were

encouraging, the players both found it fun and easy

to understand how to play, and they also found that

the exercises were useful.

6.1 Interacting with the Game

All agreed (one strongly) that it was easy to navigate

in the game, but all except one also agreed that it

was confusing with all the different poses. One also

said that it was difficult to see, and particularly to

read the text, because of cataract

. However two

found it difficult to understand the rules at first.

These findings were confirmed by the

observation protocols. Some players had initial

problems, three out of the six had to repeat actions,

but we observed a learning effect by all the players

except one who did not have problems.

The players

found the avatar ugly, but they still understood that

the avatar was mimicking their own movements.

6.2 Game Exercises

Since this was a lab test to see how the players react

to this kind of exergame, there were no physical

measurements and also no physiotherapist present

during the testing. However, we wanted to know

whether the seniors themselves perceived the

exergame as real exercises, and their perceived

usefulness of the game is summed up in Table 1. All

six found that the exercises were good for them and

that a game like this was useful. We also wanted to

know if they would recommend the game to friends,

since this gives an indication about how they find it.

One would not recommend it, the other five would.

One also said that it is important to move all the

time, and that through exergaming they would do

exercises they would not have done otherwise.

A woman who had osteoarthritis said that the

exercises were good for her. One even said that she

got exhausted because it was so hard to get the key

and therefor she had to walk a lot.

Table 1: Perceived usefulness of the game as physical

exercise. Number of persons who 1: disagree strongly, 2:

disagree, 3: neither agree nor disagree, 4: agree, 5:

strongly agree.

1 2 3 4 5

It is easy to perform the exercises 2 4

The exercises are good for me 1 5

I feel safe when I play the exergame 2 4

The game is useful for me 2 4

It is easy to understand the game

rules

2 2 2

I liked to play the game 2 4

I would recommend this game to

friends

1 4 1

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We asked what they liked the most, and we got two

replies; one said the arm movements were the best

while another one liked best to find the key; and this

latter was the one who had the biggest problems

finding it.

We also asked whether they would prefer to

exercise at regular times, and four out of six

confirmed that they would.

6.3 Other Issues

Some other issues also emerged during the

observations and interviews. The main impression

based on the observation protocol is that all were

very eager during the play. They seemed interested,

and played through the entire game.

All six found that the graphics were OK in the

new version and, that it was easy to get an overview

(three agree and three strongly agree), but one out of

the six thinks there was too much information. Five

also agreed that they liked the music while one was

neutral – he told that he had not noticed that the

game had background music, since he was

preoccupied with the gameplay.

One person would like more rhythm in the game

and one had problems catching the key. Another one

tended to walk forwards and had to move back. One

person also forgot how to turn, but all learnt during

gameplay.

A general observation is that all the players

seemed to find the game fun. We noticed that our

game

had problems registering the walking of

particularly two women. We don’t know why, but it

could be that the game was not calibrated to their

bodies. They did not wear skirts or clothes that

might disturb the way they are tracked by the

Kinect

camera.

Also at the end they wanted to stay in the garden

and walk around after they had found their collected

items and received the final reward.

In the group discussion we tried to get some

comments about the difference between the Wii 2D

games they were used to play, and this new 3D

game. Some had not noticed the difference and some

said the 3D game was more challenging. All the

players agreed that the avatar was ugly, but they

liked that they could play at their own speed.

7 DISCUSSION

7.1 Playing a 3D Game

The participants enjoyed the game prototype, but

they also found it challenging. This is in our opinion

a good thing, since gameplay is about learning and

mastering. If it is too easy the first time, they will get

bored quickly.

Also the interface gave some challenges. To start

with the participants had some problems moving

around in a 3D environment. However, they seemed

to learn pretty fast, although some of them moved

too much around on the floor and ended up too close

to the camera. One participant even wanted to move

around in the 3D environment to search for the key,

and the others wanted to stay in the game garden

after the game was over. We think this shows that

the players liked the 3D environment. Maybe this

environment gives the game more life and in

particular makes the game environment more similar

to real life? We feel that a 3D exergame can be

further investigated for this target group.

Figure 6: Collecting items in the room.

Some found the different poses confusing. Since

this was the first time most of the players tried

Kinect

, it was probably a bit overwhelming both

to learn how to control the avatar and to play the

game. (Juul and Norton, 2009) point out the border

between interface and gameplay is not always clear,

and when the interface is a totally new technology

for the players this is important. Since they learned

during the gameplay, we think that they also will get

familiar with the poses if they play regularly.

The game should also have been calibrated to

each person, which we did not do because of time

constraints. This fact could explain the previously

stated difficulties a couple of our players had.

Many in our target group have problems with

lifting one or both arms, particularly above the

shoulders. It should be possible to personalise the

game, for instance, by calibrating each user’s

possible range to lift the arms. In this way we can

ensure that all are able to play with their abilities.

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7.2 Graphics

The first graphics were not made particularly with

elderly in mind. In the first version it was more

important to make the game mechanics work. The

graphics of this version were thus rudimentary and

the players had problems to see items due to

patterns, colours and sizes. We also had some

comments about the ugly avatar that was basically

an avatar skeleton mimicking the users’ movements.

7.3 Exercises and Usefulness

The main purpose of the exergame is to motivate to

physical activities. The players reported that they

felt that this game gave good exercise, and they

particularly liked that they had to use their arms.

We could observe that some got exhausted by

walking, since they had to step in place in all three

scenes. In this first version they can wave and hug

themselves in the first scene, but it is only in the

room scene that they really get to use the arms. With

a careful design of more scenes, we think that this

game can give a varied set of exercises and still be

fun to play. However, this must be tested with a

more mature version and with a larger number of

players over time.

7.4 Social Gaming

The game was originally designed as a multiplayer

game, and this has been tried by researchers, but not

yet by the main target group. So as to not embarrass

or disturb the players, they are only supposed to see

the other players in the first and last scenes, while in

the “real” exercise scenes they can perform the

exercises at their own speed and level without

anyone seeing what they do.

To be able to play simultaneously, the players

have to agree upon a time to play. We think that it

can be motivational to see that others also are

coming to the training sessions, but this still remains

to be demonstrated. Also most of our test persons

said that they would prefer to train at appointed

times. In a multiplayer mode you can play at set

times, and also see who else are playing.

7.5 Other Issues

One of the players wanted the game to contain more

rhythm. This is not in the current game design, but

for instance, it could be possible to include a room

with dance music where the players can move to the

rhythm.

One person also asked for the key to be randomly

placed, and maybe it would also be possible to

create an exercise scene where the players have to

search for items behind things. This can also be

considered in a future game design.

8 CONCLUSIONS

The main conclusion is that seniors can grasp a 3D

gaming environment as in our game quite easily, and

they can learn how to navigate around and play with

different poses and body actions. They also find it

challenging and fun, and many would recommend it

to friends. This means that the game could be

motivational to play. We also see that they actually

have to perform the correct movements to achieve

the game goals.

We know that many elderly play commercial

exergames regularly on senior centres and nursing

homes, also Kinect

games. We do however think

that many of those games are not suitable for our

target group. The game prototype gave the players

the possibility to have only one focus of attention,

and they can take the time they need to manage the

tasks, and the trials were promising. In a later

version we must however spend more time on

graphics and colours. Also the avatars should get a

facelift since they actually represent the players.

We also think that this gives a better opportunity

to implement exercises that are useful for the

elderly, and they will be able to perform more

controlled movement. It should, however, be

possible to have a chair for support for those who

might be afraid to fall. Nevertheless, we realize that

we need to spend time on calibrations, since some

had problems interacting properly with the game.

Last but not least – a game must still be a game

even if the players are old. There should be goals

that are hard, but not impossible to reach, there must

be challenges, and a game both needs good feedback

during play and rewards when the goal is reached.

In future work the game should be further

developed with more scenes, better graphics and the

possibility to make user profiles and maybe

personal avatars. Studies should both consider

whether the game can motivate to increased physical

activity, including in multiplayer mode as well as if

the game has a physical effect.

ACKNOWLEDGEMENTS

We would like to thank the senior centre for helping

Experiencewitha3DKinectExergameforElderly

237

us to recruit seniors for the trials. We also thank the

players who spent some hours with us playing and

giving their feedback. The study was performed in

the JoinIn AAL project Join-In partly financed by

the Norwegian Research Council.

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