Application of Mobile Technologies in the Preparations for Long

Distance Running

Ladislav Havaš

, Vladimir Medved

and Zoran Skočir

Department of Electrical Engineering, Polytechnic of Varaždin, Križanićeva 33, Varaždin, Croatia

Faculty of Kinesiology, University of Zagreb, Zagreb, Croatia

Faculty of Electrical Engineering and Computing, University of Zagreb, Zagreb, Croatia

Keywords: Expert System, Long Distance Running, Mobile ICT Technologies, ORT, Training Equivalent, Training

Process.

Abstract: Fast development of mobile ICT technologies has enabled and imposed their implementation in many

business, private and sport areas. As mobile technologies enable quick and two-way communication,

independent of the present location of an athlete, their trainer or expert hardware and software systems, it is

of the significant importance to utilize the advantages of that kind of communication in order to maximize

the chances of achieving excellent results in a specific training process or in a key race. In this paper is

shown one ORT (Online Running Trainer) system, which was developed for preparations of long-distance

runners. It describes a new algorithm for calculation of training equivalents of set and achieved trainings,

which was used for the success analysis of every micro cycle of the training process. By using all available

telecommunication channels, ORT system communicates with its users in real time. Moreover, it analyses

their performance and, if necessary, dynamically corrects their training parameters in order for them to

achieve better results in a needed moment. Described methods and procedures are verified on a selected

sample of marathon runners.

1 INTRODUCTION

Nowadays, modern mobile ICT technologies follow

up an athlete in all stages of their preparations. It

helps him in developing a program of their

preparations, ensures him an access to important

information in the right moment and enables the

storage of current parameters and information

related to training process or to a particular training.

Major expansion in the development of mobile

phones of all sizes, with great processing

capabilities, affordable prices and intuitive user

interface, has made the users of all sport,

psychological and cognitive categories capable of

using telecommunication services during the indoor

and outdoor workouts. In that way, there are

possibilities of an individual approach to a single

athlete, regardless of their current location, and the

communication between the athlete and their coach

or between the athlete and the system that cares for

athlete`s results is facilitated. In a situation where

there is an expert system that has the ability to

generate a program for athletic preparations and the

ability to evaluate given and performed trainings in

real time, mobile telecommunication channels

become dominant communication platform between

the system, a coach and his athlete.

In this paper is shown one such system which

helps long-distance runners in developing their

program for preparations, and by using available

mobile ICT technologies it stores, analyzes the

information and advices them in real or near-real

time. Ineffective trainings are dynamically changed

with solutions that are safer and that faster lead to

the preferred result, with lesser chance of sport

injury. The second part of this paper describes the

architecture of one “Online running training system”

(ORT), while the third part of the paper shows

telecommunication platform which is used for two-

way communication with users. The fourth part of

the paper describes the methods and algorithms

developed for evaluation of given and performed

workouts in the preparation program for 5K runners

to marathon runners. In the fifth part is described

and shown the verification of results on a selected

sample of marathon runners. The final part of the

154

Havaš L., Medved V. and Sko

cir Z..

Application of Mobile Technologies in the Preparations for Long Distance Running.

DOI: 10.5220/0004702501540161

In Proceedings of the International Congress on Sports Science Research and Technology Support (icSPORTS-2013), pages 154-161

ISBN: 978-989-8565-79-2

 2013 SCITEPRESS (Science and Technology Publications, Lda.)

paper gives a conclusion and the list of references.

2 REPRESENTATION OF ORT

SYSTEM

The prototype of the system was developed by using

open-source programs (PHP, MySQL, Linux). The

whole applicative solution was launched on the

Linux distribution of CentOS 6.4, version 5.3.3 of

objectively-oriented PHP language, on MySQL

server relational database distribution 5.67 (MySQL,

available at: http://www.mysql.com, accessed on 07

July 2013), and on Apache web server 2.2.15.

Individual applications are run by cron (crontab,

cron table) service.

2.1 The Architecture of an expert

System

The first display which users of prototype of ORT

system encounter is shown in the Figure 1.

Figure 1: Opening display of prototype of ORT system (in

Croatian language).

During the registration process, users define their

user name and their password, they enter their

personal info, the number of their mobile phone and

their e-mail address where they receive an activation

link. Due to the security reasons, user’s password is

encrypted with MD5 algorithm, 128-byte

cryptography hash function, ratified Internet

standard RFC 1321, and in that form it is being

stored in the database. When the user has

successfully logged in, he or she is presented with an

appropriate menu, in accordance with his or her

authorization levels. A specific part of the menu

functions/options is shown or hidden from the user.

2.2 Generating the Training Program

One of the frequently used functions of the system is

“Program generating”. The main task of that

subsystem is to create a program for preparations of

long-distance runners for following distances:

 5000 m (5K)

 10000 m (10K)

 21097 m (half marathon)

 42195 m (marathon)

After the user enters the results of his/her current

sport capabilities (race or training), the system

calculates their maximum aerobic capacity (VO2

max

factor), which serves the purpose of estimating

runner’s potential on the races from 800m to

marathon, which is going to be used in the future

workouts. Then the runner selects a specific

discipline for which he intends to prepare, the length

of the program (between 12 and 24 weeks), the

starting date, selects the upper limit of the acceptable

weekly mileage and decides on the toughness of the

program (Program A – beginners), (Program B –

advanced) or (Program C – elite). The opening

display for entering the parameters needed for

generating the program is shown in the Figure 2.

Figure 2: Entering the basic parameters for generating the

program (in Croatian language).

2.3 Running Log

All the done workouts the user can and should

inscribe in the second important module called the

“Running Log” by using the available

telecommunication channels and by doing so enable

evaluation and the comparison of envisaged and

performed workouts.

Selecting the appropriate day and the input of

relevant data is possible to render in real time,

during the workout or immediately after the

workout, but also backwards, which allows the user

to completely fill in the Running Log in order to get

the review of your performance as detailed as

possible. Aside from the usual track of each workout

(when, how much, how fast, the type of training…),

the user has the ability to mark their own training

based on their biased perception (tiredness, lack of

sleep, humidity, temperature, wind and other

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aggravating factors) through VAS scale (Visual

Analog Scale), which is known as a frequently used

medical psychometric method that has been used for

evaluating the sense of pain. That scale enables the

choice of values between 0 and 10, wherein 0 would

stand for ideal conditions for a workout and values

closer to 10 would stand for less ideal conditions,

thereby done workouts should be also assessed in

accordance with appropriate correction factor. With

the possibility of inputting the data through web

(version 2.0), other methods have also been

developed which use mobile telecommunication

channels and allow the user to communicate with

ORT system in real or almost real time through e-

mail (smart phones) or through SMS.

3 THE ARHITECHTURE OF THE

TELECOMMUNICATION

PLATFORM

A telecommunication system was developed which

has the purpose of enabling the exchange of

information in real time with the users through

several different telecommunication interfaces.

The information which the users exchange with

ORT system have to be in a specific format which is

set by the protocol for exchange of the data that is to

be mentioned in the following parts of this paper.

All information which, through different mobile

channels, arrive to the system are being stored in the

Running Log. From there they are periodically

filling by ETL process (Extracting, Transforming,

Loading) into the data warehouse, and after

extensive analyzes users can inform themselves

about the quality of their workouts in the past period

of time. The flow of information between the user

and the system is shown in the Figure 3.

Figure 3: The flow of information between the modules of

the system.

From the Figure 3 can be seen that there are

supported following methods for exchange of data

between the user and the database:

 Web

 E-mail

 SMS

By using different Internet browsers (Firefox,

Google Chrome, Opera, Safari…) users inscribe

their done workouts into the system, for the purpose

of their use in the feedback analysis. In case of the e-

mail method the users use available e-mail clients,

which they sent their e-mail messages to. The

advantage of this method lies in the fact that the

majority of smart phones support e-mail function

through some of available e-mail clients. In that way

an interaction between distant users and the ORT

system is enabled, provided that on a particular

location there is a signal of one mobile network.

SMS, as a third method for exchanging the

information, enables the communication in real time

with the users that are owners of older cell phones

which do not posses an e-mail function. The limit of

this communication method lies in the fact that the

upper limit of characters in one sms is 160. In the

follow-up, mentioned methods will be thoroughly

presented.

3.1 ORT Web Module

By using the Web module, it is possible in a simple

and intuitive way to develop a communication with

a Running Log. By launching one of available

Internet browsers and by entering the appropriate

menu of ORT web application, one is able to update

the Running Log. In the Figure 4 it can be seen the

opening display which a user sees upon entering.

Figure 4: Running Log (in Croatian language).

It always shows the current month, but there is a

possibility of going backwards, in case a runner

wants to inscribe some new information or to update

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the existing ones.

Boxes labelled with red stand for the days in the

month for which the user has been given a particular

workout, but still has not inscribed feedback

information on that particular workout. Boxes

labelled with green stand for the days in the month

for which the user has inscribed feedback

information, whereas white boxes stand for the days

when there is no given workout. Using the Web

interface is the main method for determination and

the analysis of given and done workouts. Other

telecommunication channels such as e-mail and

SMS are used in order to provide the runners with

the ability to directly communicate with the

application during or immediately after the workout.

Access to the Web interface is enabled through

HTTP protocol (Hypertext Transfer Protocol).

HTTP protocol is the protocol of application

(seventh) layer of OSI model (Open Systems

Interconnection) and functions by using “Request-

Response” method in which the Web server and the

client participate.

On a server which runs ORT application is

installed and set Apache2 Web server. That Web

server is always active and awaits new requests on a

network port 80. Upon receiving new HTTP request

which is initiated by a client, ie. user of a Web

browser, web service will, from local disc, reach

predefined data files inscribed in the form of HTML

(HyperText Markup Language) record which

presents ORT Running Log.

One such transaction is shown in the Figure 5.

This type of joining the database is impractical for

mobile phones with small displays.

Figure 5: HTTP transaction.

3.2 ORT e-Mail Module

This module is used for processing and sending e-

mail messages. For its work it uses IMAP (Internet

Message Access Protocol) and SMTP (Simple Mail

Transfer Protocol) protocols. Module is, at very high

frequency and through IMAP protocol, connects to a

mailbox of an electronic mail of ORT system in

which it finds e-mail messages of the users. The

system will, in accordance with programmed

protocol for exchanging the information, check the

accuracy of information and will notify the user on

the outcome of his request through SMTP protocol.

An example of the transaction performed through

ORT e-mail module:

User inquiry:

From: lhavas@velv.hr

To: ort.trener@gmail.com

Subject: ?

A response from ORT system:

From: ort.trener@gmail.com

To: lhavas@velv.hr

Subject: ORT Help

Dear user,

Welcome to ORT system for training

receive help for a specific type of

training please enter one of the

following phrases in the SUBJECT of an

e-mail message on the address

ort.trener@gmail.com:

I? – for an interval training

S? – for a superset training

T? – for a tempo training

L? – for a prolonged training

R? – for a recovery training

X? – for an alternative training

Example: Subject: I?

Kind regards,

Your ORT!

In case the user, for example has done an interval

training according to given instructions, it is possible

to inscribe the training in the database through an e-

mail in the following way:

From: lhavas@velv.hr

To: ort.trener@gmail.com

Subject:

#I*400*00:01:30*10*120*12000*60*180*120

*145*980**7*demo training example#

All successfully registered trainings are inscribed

in the database in real time in the Running Log.

The next example shows an e-mail communication

between the user and the ORT system in details:

An e-mail client, which is installed on the user’s

cell phone will connect, through SMTP protocol,

with one of the outgoing e-mail servers and issue a

request for sending an e-mail message of the

predefined content. That e-mail server will parse an

e-mail address on local-name@domein and will,

based on that, draw a conclusion in which domain

the user is located. Through DNS (Domain Name

System) request, it will ask for MX (Mail

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Exchanger) record of the domain, whose response

will provide it with the information on the list of

names of serves and associated priorities for the

domain in concern. E-mail server with the lowest

priority will be the destination on which prior listed

e-mail servers will send message to. When that

message is being delivered to the destination server,

it will be reachable in the user’s mail box IMAP

protocol, which is shown in the Figure 6.

Figure 6: Display of e-mail communication between the

ORT server and the ORT user.

3.3 ORT SMS Module

The ORT SMS module is used for communication

with the users whose mobile phones do not support

e-mail function. With the fact that one sms is limited

to 160 characters, the main flaw of this subsystem is

in its unprofitability in regard to free and as fast e-

mail messages. ORT system sends SMS messages

by using SMS service called Clickatell.com.

Clickatell.com SMS service accepts HTTP

request whose URL (Uniform Resource Locator)

address possesses all needed information for sending

SMS. As a HTTP response on the previous HTTP

request, one receives a confirmation whether a

message has been successfully sent. When

Clickatell.com through HTTP protocol takes over all

necessary information, SMS is, in accordance with

the request, directed all the way to the

telecommunication mobile operator on which there

is a mobile phone of the ORT user.

4 EVALUATION OF THE

TRAINING QUALITY

Dynamic management of training process is

impossible without methods and algorithms for

evaluation of the quality of given and performed

workouts. The following segments of this paper will

briefly describe the methods for calculating the

numeric equivalent of basic training elements in the

athletic preparations of marathon runners. Firstly,

an algorithm for determining the training equivalent

of given trainings will be described, then the

procedure for evaluation of done training will be

described.

4.1 Given Trainings

Long Run:

Long Run is the basis of all programs for long-

distance running, and especially of the program for

preparation of marathon runners (Havaš and Vlahek,

2006). The effort should not be too high as one

should run in the aerobic zone.

Due to the above-mentioned reasons, for each 15

minutes of running, ORT system adds 5 points to the

total training equivalent.

Tempo Training:

During the determination of training equivalent in

tempo training, potential of the user is also taken

into consideration along with the duration of the

training, in regard to his currently calculated

maximal aerobic capacity VO2

max

In case that a tempo training means running in

the tempo of a marathon, the duration is calculated

in seconds and compared with the anticipated

capabilities of that particular runner. Calculated

training equivalent is a percent of the training

duration in seconds in regard to maximum duration

in seconds which is anticipated for a user based on

his anticipated result. Anticipating the potential is

realized by a method of dr. Daniels and Gilbert

(1979).

Speed Training:

From many known speed trainings, in ORT system

are used Interval training and Super set training.

The first step is to calculate the percentage of the

run distance at the given tempo. In case one runs at

the tempo of 5000m race, and one runs 4000m (10 x

400m), that implies training equivalent of 80%, or

80. That equivalent is decreased 0,5 points for every

15-second break between intervals.

Recovery Training:

Recovery trainings are not physiologically

demanding, which means that during the calculation

of the training equivalent only the duration in the 15-

minute intervals is calculated. Every hour of such

training gives the runner 20 points to the total

training equivalent.

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4.2 The Analysis of Done Trainings

When the database receives the data from done

trainings, it is also necessary to calculate their

training equivalent. Methods that are explained for

calculating the training equivalent are used, although

some new parameters are also introduced, for the

purpose of even more detailed evaluation of

achieved effects.

Aside from all known parameters that are used in

trainings and serve the purpose of calculating the

training equivalent (speed, duration, distance,

number of trials, duration of recovery periods etc...),

the user has the ability to inscribe some additional

values:

 HR – maximum, minimum or average heart

rate during the training

 Kcal – burned calories during the training

 Lactates – concentration of the lactic acid in

the blood

 VAS - subjective estimate of the training

conditions (temperature, humidity, wind,

biorhythm, tiredness, lack of energy…)

Every one of those parameters influences the quality

of the evaluation of done trainings.

HR (Heart Rate):

Each user should (by using some of the suggested

methods (Heart rate training zones, available at:

http://www.brianmac.co.uk, accessed on 01. April

2013)) calculate their maximum heart rate and

inscribe the data into the ORT system. By knowing

the maximum heart rate of every user (HR

max

), it is

possible to estimate has the particular user resided in

a specific HR zone, which is usual for that type of

training.

Particular trainings and running tempos of a

certain part should be done within one of the zones

(Polar sport zones for running, available at:

http://www.polar.com/en, accessed on 29. December

2012):

 Zone 1: 50-60% of the maximum heart rate

(very easy, daily activities)

 Zone 2: 60-70% of the maximum heart rate

(easy activity, fat burning zone)

 Zone 3: 70-80% of the maximum heart rate

(aerobic zone, a moderate effort)

 Zone 4: 80-90% of the maximum heart rate

(anaerobic threshold)

 Zone 5: 90-100% of the maximum heart rate

(very intense, competitive training)

In case a particular type of training is done within

the appropriate zone, it is not necessary to correct

the calculated training equivalent. For every jump to

a lower or to a higher zone, the system calculates +/-

20 points to the training equivalent.

Calories (Kcal):

There is no exact method which would allow for a

precise calculation of how many calories a runner of

a certain weight, sex and years of age consumes at a

certain speed of running in a particular period of

time or a duration interval. On top of that, it has

been noticed that there is a specific correlation

between the heart rate and the consumption of

calories for user. One of the more quality methods

that takes into account above-mentioned parameters

as well as maximum aerobic capacity has been

suggested in (Keytel, at al., 2005) and it was used in

the prototype of the ORT system for calculating the

number of consumed calories. In case where the

maximum aerobic capacity VO2

max

of an individual

is known, then:

formula for men is:

((-95.7735 + (0.634 x HR) + (0.404 x VO2

max

)

+ (0.394 x W) +(0.271 x A))

/4.184) x 60 x T (1)

formula for women is:

((-59.3954 + (0.45 x HR) + (0.380 x VO2

max

) +

(0.103 x W) +

(0.274 x A))/4.184) x 60 x T (2)

Where is:

HR = heart rate per minute

W = weight in kilograms

A = age in years

T = duration in hours

VO2

max

= max. aerobic capacity in ml/kg/min

Lactates:

The speed of creating lactic acid is proportional to

the speed of running, ie. it is proportional to the

percentage of used maximum aerobic capacity. For

the trainings that are at marathon tempo, the

concentration of the lactic acid should not be

crossing the level of 2mmol/L of blood. For the runs

that are at the tempo of half-marathon, it is predicted

that lactates do not cross the level of 4 mmol/L of

blood, while for the runs at the tempo of races on

10000, 5000 and 3000 meters, the concentration of

the lactic acid is significantly higher than 4 mmol/L

of blood. Every discrepancy from the prescribed

intervals, the ORT system evaluates with the

correction of the training equivalent by +/- 15 points.

VAS (Visual Analogue Scale):

In the ORT system it is used as a unique indicator of

the quality of the training conditions. For all values

between 0-4 it is considered that the conditions were

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159

adequate, and accordingly the training effect remains

unchanged. For each value higher than 4, calculated

training effect is increased by 5 points.

Mentioned values can be subjected to certain

changes for the purpose of increasing the quality of

training evaluation. Since the developed system has

the ability of self-learning, those parameters will be

changed in time to more optimal values of those

factors.

5 VERIFICATION AND

ANALYSIS OF THE RESULTS

5.1 Verification of the Results

Developed system for generating programs and the

mobile surveillance of the quality of the training

process has been verified on a selected sample of

marathon runners, which allowed for an evaluation

of the quality of implemented methods and

algorithms, for the purpose of correcting or

updating, if necessary, some of the methods used.

Selected and analyzed were the runners of both

sexes and in the age range from 18 to 65.

The number of people who have fulfilled all of

the above-mentioned conditions is 58. Among that

group there were some beginners, some advanced

runners and some were the elite runners who have

won many marathons and ultra marathons.

In the Table 1 is shown one part of the users who

have participated in the process of the results

verification. For the sake of easier statistical

analysis, all time measures into seconds.

Table 1: Display of one part of verified users and their

results.

5.2 Statistical Analysis of the Results

IAAF (International Association of Athletics

Federations) evaluates runners and their results in 5-

year classes, and in this paper the runners and their

results are evaluated according to their sex and

whether they are between 18-29, 30-50 and more

than 50 years of age. Moreover, they have also been

assessed according to toughness level of their

preparations. Program A (marathon slower than

3:30:00), Program B (marathon between 3:00:00 and

3:30:00) and Program C (marathon faster than

3:00:00).

For the analysis of included data, a descriptive

statistical analysis was used (Lipschutz and Schiller,

1998), while for the graphical display of data

distribution there were used rectangular diagrams

(Box and Whisker plot). Statistical processing of

data has been done by using a mathematical

applicative programme “Matlab 7.0.1” and the

application Microsoft Excel 2013. Statistically

significant in the analysis were confirmed

discrepancies at the significance level of p<0,01.

Athletes included in the research were old, on

average, 34,16 years, wherein the standard

deviation is 9,87 years. Range of variation has the

value of 47 since the youngest participant is 18,

while the oldest is 65.

During the research of correlation between

achieved and planned result, Pearson’s coefficient of

correlation has been calculated. Based on the value

of the coefficient of correlation and the p-value

derived during the testing of the hypothesis on

statistical significance of the analyzed variables

(r=0,9926 i p=0,0000), it can be concluded that

there is a statistically significant positive correlation

between the observed variables. The graphical

display of the correlation between achieved and

planned result is given in the Figure 7.

Figure 7: Correlation between achieved and planned result

(in Croatian language).

Distribution of the data obtained during the research

has been verified with “Kolmogorov – Smirinov”

test. Since the distribution of the data substantially

deviates from the normal distribution, for calculating

statistically significant discrepancies between the

three groups has been used non-parameter (Kruskal-

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Wallis) test. The results of the Kruskal-Wallis test,

which relate to planned time for the programs A, B

and C indicates that there is statistically significant

difference in planned time between the groups

(H=50,4978 and p=0,0000). Test for multiple

comparison has confirmed that all three groups

(three toughness levels) are statistically substantially

different. In order to achieve that kind of results, in

more than 50 % of the users it was necessary to

dynamically modify the training process.

Figure 8 gives a graphical display of the drawn

conclusion from a statistical test.

Figure 8: Planned result (s) in regard to different

toughness level (in Croatian language).

All necessary corrections of implemented algorithms

and the evaluation of particular training elements

were automatically implemented into the system.

6 CONCLUSIONS

This paper shows modelling of a system for mobile

telecommunication support in athletic preparations

of long-distance runners. This is a very complex area

which is intensively growing and in the future is

going to be a subject of many analyzes and the

opportunity for implementation of new ideas and

algorithms.

Here was described one telecommunication

platform which in real time communicates with

athletes, evaluates their given and done workouts,

and, if necessary, dynamically modifies the rest of

their training process for the purpose of achieving

better results. Functioning of an expert system which

generates programs for preparations in popular long-

distance disciplines (5000m, 10000m, half-marathon

and marathon) was presented in this paper.

Developed system is dimensioned for simultaneous

interactive use by a large group of users. Flexible

environment was created which protects the

individuality of each athlete, who decides on their

own on the volume of their training, the starting

date, toughness level as well as chooses one of the

available telecommunication channels for the data

transfer. As opposed to many other web services and

available books, at this point there it does not end

the interaction with the developed system. Database

and the data warehouse were formed which are

being updated in real time and the algorithms for

evaluation of given and done trainings have also

been developed.

Research on this topic has been directed at

integration of all above-mentioned segments,

generated program and the feedback information in

the shared database, by using mobile

telecommunication channels for data transfer in real

or almost-real time. Verification of the algorithms

and the methods has been conducted on a limited

sample of marathon runners. The procedure of

verification where the database and the data

warehouse have been filled with new quality data on

daily basis has led to enabled self-learning and

constant improvement of implemented algorithms

for generating programs for evaluation of results.

By a modular concept of the database the data

warehouse and by using the technologies and the

tools of open-source codes, it is relatively easy to

extend the system with new hardware and software

modules.

The procedure of verification has shown that

dynamic correction of generated programs in real

time, by using ICT technologies and implemented

algorithms and methods, substantially decreases the

probability of not achieving adequate result with the

increased probability of achieving the desired result

in optimal conditions.

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