Mittauksia suoritettiin eri ryhmillä seuraavien turnaustapahtumien aikana:

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2 1 JOHDANTO Urheilussa harjoittelun tarkoituksena on kehittää urheilijan eri ominaisuuksia niin, että lajisuoritukset paranevat. Harjoitteluvaikutuksen syntyminen perustuu elimistön tai sen osan homeostaasin järkkymiseen ja siitä aiheutuvaan elimistön adaptoitumiseen. Jos homeostaasia järkyttäviä harjoituksia toistetaan sopivilla palautuksilla, niin harjoitetut ominaisuudet kehittyvät. Autonomisen hermoston säätely häiriintyy mm. kovan harjoittelun ja/tai psyykkisen stressin vaikutuksista (esim. Furlan ym. 1993; Pichot ym. 2000). Vakava ylikuormitustila näkyy autonomisen hermoston säätelyssä lepotilassakin (esim. Uusitalo 2001; Mourot ym. 2004). Lisäksi on havaittu, että ylikuormitustila heikentää kognitiivista suorituskykyä (Hynynen ym. 2007) ja jo parin viikon intensiivinen harjoitusjakso voi heikentää reaktioaikaa (Rietjens ym. 2005). Aiempien KIHUssa tehtyjen tutkimusten pohjalta on kehitetty uusia sykepohjaisia autonomisen hermoston säätelyn tasapainon mittausmenetelmiä (Hyvinvointianalyysi, Firstbeat Technologies Oy), joita voidaan käyttää kuormittumisen ja palautumisen arvioinnissa (mm. Martinmäki ym. 2005; Hynynen ym. 2006; Nummela ym. 2006). Näitä mittareita hyödynnettiin kaksivuotisessa TEKESprojektissa, missä kehitettiin eri lajien urheilijoiden kuormittumisen ja palautumisen seurantamenetelmiä. Mukana olivat maastohiihto, ammunta, ampumahiihto, yleisurheilun teholajit ja miesten jalkapallo. Sykevaihtelutietoon perustuva autonomisen säätelyn arviointimenetelmä huomioi palautumisen kokonaisvaltaisemmin kuin muut palautumisen arvioinnissa käytetyt menetelmät, koska sykedataa voidaan kerätä taukoamatta esimerkiksi koko rasitusta seuraavan vuorokauden aikana (Tummavuori 2005; Hynynen ym. 2006; Nummela ym. 2006). Menetelmää on myös käytetty kori- ja lentopallossa (Häyrinen ym. 2007). Erityisesti kestävyyslajien harjoittelun apuvälineenä käytetyt ja kehitetyt seurantamenetelmät ovat antaneet erinomaisen avun kovien harjoitusleirien kuormituksen hallintaan (Hynynen ym. 2006). Jalkapallonuorilla tehty pilottitutkimus antoi viitteitä menetelmän sopivuudesta lajiin ja aerobisen kestävyyden merkityksestä objektiivisesti mitattuun ja subjektiivisesti arvioituun palautumisen (Luhtanen ym. 2007). Tämän projektin tarkoituksena oli soveltaa viimeisintä osaamista kuormittumisen ja palautumisen seurannassa naisten ja nuorten jalkapallomaajoukkueiden valmistautumiseen kohti naisten EMlopputurnausta Suomessa 2009 ja Lontoon olympialaisia Projektissa seurattiin sykepohjaisten mittareiden avulla autonomista säätelyä ja sitä kautta pelaajien kuormittumista ja palautumista.

3 2 MENETELMÄT Projektiin osallistuivat naisten, U19-tyttöjen ja U18-poikien jalkapallomaajoukkueiden urheilijat. Urheilijoilta kerättiin syketietoa harjoituksissa ja otteluissa kuormituksen aikana ja lisäksi harjoitus- ja ottelupäivien jälkeisinä öinä. Näin päästiin vertailemaan erilaisten otteluiden ja harjoitusten kuormittavuutta ja niiden vasteita öiden aikana mitatuissa ja lasketuissa sykevaihteluun perustuvissa muuttujissa. Sykeseurannat toteutettiin Suunnon Smart Belt -sykevöillä ja sykevaihtelu analysoitiin FirstBeat Sports - ohjelmalla (ohjelmaversio , Firstbeat Technologies Oy, Suomi). Yösyketiedon analyysiin valittiin neljän tunnin jakso siten, että sykevälitiedon analysointi aloitettiin puoli tuntia nukkumaanmenon jälkeen. Sykevälitietojen häiriöiset kohdat poistettiin käyttämällä kriteerinä FirstBeat Sports - ohjelman virheellisen sykevälitiedon korjausta. Kunkin urheilijan yöstä mitattu sykevälitieto analysoitiin, jos analysointikelpoista sykevälitietoa oli vähintään 2,5 tuntia. Muuttujina käytettiin kuormitusten aikana maksimi- ja keskisykkeitä sekä peakepoc-arvoja. Yömittauksista käytettiin hyvinvointi-, stressi- ja palautumisindeksiarvoja. Mittauksia suoritettiin eri ryhmillä seuraavien turnaustapahtumien aikana: U18-pojat Granatkin-turnaus, Pietari Lisbon International -turnaus, Lissabon Naiset, A-maajoukkue Algarve-turnaus, Algarve Ottelumatka USA:han Skotlanti-ottelut Suomessa U23-naiset Avoimet PM-kisat, Suomi U19-tytöt Leiri, Vantaa EM-jatkokarsinnat, Wales Tapahtumien aikana valmentajat ja pelaajat saivat palautetta kuormitus- ja palautumistiloista ja tapahtumien jälkeen hieman tarkemman palautteen tuloksista.

4 3 TULOKSET JA TUOTOKSET Edellä esitetyistä mittausjaksoista tarkempaan analyysiin valittiin U18-poikien Granatkin-turnaus ja naisten Algarve-turnaus. Näiden tapahtumien aikana tehtyjen mittausten tuloksista tehtiin kaksi posteriesitystä kansainvälisiin kongressitapahtumiin. Häyrinen, M., Luhtanen P., Juntunen, J., Hynynen, E., Vänttinen, T., Lipponen, K., & Heliskoski, J. (2007). An evaluation of physical loading, recovery and stress in youth soccer. Science for Success II, Promoting Excellence in Sport and Exercise, Congress Book, s. 67, Jyväskylä, Finland, Häyrinen, M., Luhtanen P., Juntunen, J., Hynynen, E., Vänttinen, T., Käld, M., & Matikainen J. (2008). Evaluation of physical loading, recovery and stress in women s soccer. Hyväksytty esitettäväksi Verona-Ghirada Team Sport Conferencessä Trevisossa Kyseiset posteriesitykset ja niiden abstraktit ovat seuraavilla neljällä sivulla.

5 AN EVALUATION OF PHYSICAL LOADING, RECOVERY AND STRESS IN YOUTH SOCCER M. Häyrinen 1, P. Luhtanen 1, J. Juntunen 1, E. Hynynen 1, T. Vänttinen 1, K. Lipponen 2 & J. Heliskoski 2 1 KIHU Research Institute for Olympic Sports, Jyväskylä, Finland 2 Football Association of Finland INTRODUCTION The stress in a soccer tournament where the matches are played in very tense time table is extremely high. The training disturbs the homeostasis of many processes of the body. The regulation of the autonomic nervous system is affected by training and heart rate and heart rate variability can be used to detect these changes [1]. The overload situation of the body can be noticed from the changes of the autonomic nervous system [2]. Also it has been noticed that the overloading situation will weaken physical and cognitive performance [3, 4]. The goal of this project was to use the latest know-how in heart rate based stress and recovery measurement in improving the quality of training and team selection of the Finnish youth soccer national team. METHODS The subjects of this study were the players of the Finnish youth soccer national team in Granatkin tournament in St. Petersburg 2007 (n=18, 16 field players and 2 goalkeepers, 17.4±0.5 y, 179.8±4.8 cm, 71.2±4.6 kg). The duration of the tournament was ten days and the team played five matches in the 2 nd, 4 th, 6 th, 8 th and 10 th day of the tournament. During the tournament the subjects daily filled two questionnaires concerning their stress and recovery levels and collected heart rate during the matches and the nights using Suunto Smartbelt. The heart rate variability was analyzed using Firstbeat Sports software. The means and SDs for the EPOC, night stress index and recovery index were calculated. RESULTS The maximum EPOCs (ml/kg) for all the players who played 90 minutes were: match 1: 1. half 200±89, 2. half 151±51, match 2: 1. half 179±70, 2 half 156±63, match 3: 1. half 144±49, 2 half 113±61, match 4: 1. half 189±72, 2 half 134±72 and match 5: 1. half 156±41, 2 half 96±29. The stress indexes for the nights following matches were: match 1: 51.8±4.0, match 2: 61.0±14.4, match 3: 75.4±41.2 and match 4: 62.4±12.1. The recovery indexes for the nights following matches were: match 1: 103.2±4.7, match 2: 91.9±5.8, match 3: 95.6±14.4 and match 4: 101.6±5.3. DISCUSSION From these results it can be speculated that the lowering of EPOC-values and climbing of the stress indexes tell that the time table of the tournament was stressful and demanding for the players. Also it can be speculated that the characteristics of the match and the tactics of the team influence the stressfulness of the player a lot. The system works well in team sports like soccer in controlling the stressfulness of training and matches and the level of overall stress. REFERENCES [1] Pichot, V., Roche, F., Gaspoz, J.-M., Enjolras, F., Antoniadis, A., Minini, P., Costes, F., Busso, T., Lacour, J.-R. & Barthélémy, J.C. (2000). Med Sci Sports Exerc 32: [2] Uusitalo, A.L.T. (2001). Phys Sportsmed 29: [3] Hynynen E., Rusko H., Konttinen N. & Uusitalo-Koskinen A. (2004). 9th Annual Congress of the European College of Sport Science, July 3 6, Book of Abstracts, 236. [4] Rietjens, G.J.W.M., Kuipers, H., Adam, J.J., Saris, W.H.M., van Breda, E., van Hamont, D. & Keizer, H.A. (2005). Int J Sports Med 26:

6 AN EVALUATION OF PHYSICAL LOADING, RECOVERY AND STRESS IN YOUTH SOCCER Häyrinen, M. 1, Luhtanen, P. 1, Juntunen, J. 1, Hynynen, E. 1, Vänttinen, T. 1, Lipponen, K. 2 and Heliskoski J. 2 1 KIHU Research Institute for Olympic Sports, Jyväskylä, Finland INTRODUCTION The stress in a soccer tournament where the matches are played in very tense time table is high. The training and playing disturbs the homeostasis of many processes of the body. The regulation of the autonomic nervous system is affected by training and heart rate and heart rate variability can be used to detect these changes [1]. The overload situation of the body can be noticed from the changes of the autonomic nervous system [2]. Also it has been noticed that the overloading situation will weaken physical and cognitive performance [3, 4]. The goal of this project was to use the latest know-how in heart rate based stress and recovery analysis in improving the quality of training and team selection of the Finnish youth soccer national team. METHODS The subjects of this study were the players of the Finnish youth soccer national team in Granatkin tournament in St. Petersburg 2007 (n=18, 16 field players and 2 goalkeepers, 17.4±0.5 y, 179.8±4.8 cm, 71.2±4.6 kg). The playing system of the Finnish youth soccer team is shown in figure 1. Figure 1. The playing system of the Finnish youth soccer team. The duration of the tournament was ten days and the team played five matches in the 2nd, 4th, 6th, 8th and 10th day of the tournament. During the tournament the subjects daily filled two questionnaires concerning their stress and recovery levels and collected heart rate during the matches and the nights using Suunto Smartbelt. The heart rate variability was analyzed using Firstbeat Sports software. The means and SDs for the Excess Post-exercise Oxygen Consumption (EPOC), night stress index and recovery index were calculated. RESULTS The figure 2 represents the means and SDs of the maximum EPOCs (ml/kg) during the match, the stress and recovery indices for the following nights for all the players who played 90 minutes EPOC Stress index Recovery index 1st match 2nd match 3rd match 4th match 5th match Figure 2. The means and SDs of maximum EPOCs (ml/kg) during the match, stress and recovery indices for the players who played 90 minutes in the match. It can be seen from figure 3 that the players who play the whole match mostly achieve their maximum EPOCs during the first half of the match. The drop in the maximum EPOCs can be as high as 60 ml/kg as seen in match EPOC (ml/kg) Match 1 Match 2 Match 3 Match 4 Match 5 Figure 3. The means of the maximum EPOCs during the first and second halves of the match for the players who played 90 minutes in the match. From the figure 4 it can be seen that the role and playing position affect a lot to the stressfulness of the players. The midfield players and the wingers were physically loaded most and the goal keeper least. 1st half 2nd half Figure 4. The means of maximum EPOCs (ml/kg) for players playing in different playing positions. The means are calculated from those players who played more than 45 minutes in each match. CONCLUSIONS From these results it can be speculated that the lowering of EPOC-values and climbing of the stress indexes until the middle of the tournament tell that the time table of the tournament was stressful and demanding for the players. Also it can be speculated that the characteristics of the match and the tactics of the team influence the stressfulness of the player a lot. This can be seen from the figure 2 concerning matches 3 and 4 as the communication with the coach unveiled. The drop in maximum EPOC-values between 1st and 2nd halves probably originates from the depletion of the glycogen. The measuring system works well in team sports like soccer in controlling the stressfulness of training and matches and the level of overall stress. REFERENCES [1] Pichot, V., Roche, F., Gaspoz, F.E., Antoniadis, A., Minini, P., Costes, F., Busso, T., Lacour, J.-R. & Barthélémy, J.C. (2000). Med Sci Sports Exerc 32: [2] Uusitalo, A.L.T. (2001). Phys Sportsmed 29: [3] Hynynen E., Rusko H., Konttinen N. & Uusitalo- Koskinen A. (2004). 9th Annual Congress of the European College of Sport Science, July 3 6, Book of Abstracts, 236. [4] Rietjens, G.J.W.M., Kuipers, H., Adam, J.J., Saris, W.H.M., van Breda, E., van Hamont, D. & Keizer, H.A. (2005). Int J Sports Med 26: mikko.hayrinen@kihu.fi Science for Success II, Jyväskylä, Finland,

7 Evaluation of physical loading, recovery and stress in women s soccer Häyrinen Mikko 1, Luhtanen Pekka 1, Juntunen Jouni 1, Hynynen Esa 1, Vänttinen Tomi 1, Käld Michael 2 and Matikainen Jarmo 2 1 KIHU Research Institute for Olympic Sports, Jyväskylä, FINLAND 2 Football Association of Finland, Helsinki, FINLAND Correspondence: mikko.hayrinen@kihu.fi Introduction The stress in a soccer tournament where the matches are played in very tense time table is extremely high. The training and playing disturbs the homeostasis of many processes of the body. The regulation of the autonomic nervous system is affected by training and heart rate and heart rate variability can be used to detect these changes 2. The overload situation of the body can be noticed from the changes of the autonomic nervous system 3. Also it has been noticed that the overload situation will weaken physical and cognitive performance 1. The aim of this study was to test and utilize the latest know-how in heart rate based stress and recovery measurement with the Finnish women s soccer national team. Methods The subjects of this study were the players of the Finnish women s soccer national team in Algarve Cup 2007 (n=14, 12 field players and 2 goalkeepers, 23.5±2.6 y, 169.9±5.0 cm, 66.9±6.3 kg). The duration of the tournament was ten days and the team played four matches in the 3 rd, 5 th, 8 th and 10 th day of the tournament. During the tournament the subjects collected heart rate during the matches and the nights using Suunto Smartbelt. The heart rate variability was analyzed using Firstbeat Sports software. The means and SDs for the peak EPOC-values, night stress and night recovery indexes were calculated. Results The peak EPOC-values (ml/kg) for all the players who played more than 70 minutes in a match were: match 1: 1 st half 213±53, 2 nd half 161±49, match 2: 1 st half 218±33, 2 nd half 183±54, match 3: 1 st half 163±68, 2 nd half 135±56 and match 4: 1 st half 208±42, 2 nd half 123±30. The peak EPOCvalues during the matches were almost every time found during the 1 st half of the match. The stress indexes for the nights following matches were: match 1: 82.3±22.2, match 2: 63.0±11.0 and match 3: 59.7±10.7. The recovery indexes for the nights following matches were: match 1: 88.0±4.3, match 2: 94.2±5.9 and match 3: 95.3±7.8. Discussion From these results it can be speculated that these players were able to cope with the stress and demands of this kind of tournament. The players were able to produce similar peak EPOC-values on the fourth match and the stress indexes went down and recovery indexes got up when the tournament progressed. Still it has to be noticed that the changes in the stress and recovery indexes were highly individual. The drop in peak EPOC-values between 1st and 2nd halves probably originates from the depletion of the glycogen. The measuring system seems to work well in team sports like soccer in controlling the stressfulness of training and matches and the level of overall stress. References 1. Hynynen E., Uusitalo A. el al. (2007). International Journal of Sports Medicine. DOI /s Pichot, V., Roche, F. et al. (2000) Medicine & Science in Sports & Exercise. 32: Uusitalo, A.L.T. (2001) The Physician and Sportsmedicine. 29:

8 EVALUATION OF PHYSICAL LOADING, RECOVERY AND STRESS IN WOMEN S SOCCER Häyrinen, M. 1, Luhtanen, P. 1, Juntunen, J. 1, Hynynen, E. 1, Vänttinen, T. 1, Käld, M. 2 and Matikainen, J. 2 1KIHU Research Institute for Olympic Sports, Jyväskylä, Finland, 2Football Association of Finland INTRODUCTION The stress in a soccer tournament where the matches are played in very tense time table is extremely high. The training disturbs the homeostasis of many processes of the body. The regulation of the autonomic nervous system is affected by training and playing and heart rate and heart rate variability can be used to detect these changes [2]. The overload situation of the body can be noticed from the changes of the autonomic nervous system [3]. Also it has been noticed that the overload situation will weaken physical and cognitive performance [1]. The aim of this study was to test and utilize the latest know-how in heart rate based stress and recovery measurement with the Finnish women s soccer national team. METHODS The subjects of this study were the players of the Finnish women s soccer national team in Algarve Cup 2007 (n=14, 12 field players and 2 goalkeepers, age 23.5±2.6 y, height 169.9±5.0 cm, weight 66.9±6.3 kg). The duration of the tournament was ten days and the team played four matches in the 3rd (FIN-SWE 0-3), 5th (FIN-USA 0-1), 8th (FIN-CHN 2-0) and 10th (FIN-NOR 0-2) day of the tournament. During the tournament the subjects collected heart rate during the matches and the nights using Suunto Smartbelt. The heart rate variability was analyzed using Firstbeat Sports software. The means and SDs for the peak Excess Post-exercise Oxygen Consumption -values (peak EPOC), night stress index and recovery index were calculated. RESULTS Figure 1 represents the means and SDs of the peak EPOC-values (ml/kg) during the match, the stress and recovery indexes for the following nights for all the players who played more than 70 minutes in a match Match 1 Match 2 Match 3 Match 4 Figure 1. The means and SDs of peak EPOCvalues (ml/kg) during the match, stress and recovery indexes for the players who played more than 70 minutes in the match. Figure 2 represents the peak EPOC-values during all four matches and the stress and recovery indexes during the nights for one player during the tournament. 210 ml/kg Match Match Match Match 4 Figure 2. The peak EPOC-values (ml/kg), stress and recovery indexes for one player during the tournament. It can be seen from figure 3 that the players mostly achieved their peak EPOCvalues during the first half of the match. The drop in the peak EPOC-values was as high as 97 ml/kg for one player. 300 ml/kg Match 1 Match 2 Match 3 Match 4 Figure 3. The means and SDs of the peak EPOC-values during the first and second halves of the match for the players who played more than 70 minutes in the match. From the figure 4 it can be seen that the role and playing position affected to the physical stressfulness of the field players. The high peak EPOC-value for the goal keeper can be explained rather by the high mental stressfulness than by the physical loading EPOC (ml/kg) Stress index Recovery index EPOC (ml/kg) Stress index Recovery index 1st half 2nd half Figure 4. The means of peak EPOC-values (ml/kg) for players playing in different playing positions. The means were calculated from those players who played more than 70 minutes in different matches. CONCLUSIONS From these results it can be speculated that these players were able to cope with the stress and demands of this kind of tournament. The field players were able to produce similar peak EPOC-values on the fourth match and the stress indexes went down and recovery indexes got up. Still it has to be noticed that the changes in the stress and recovery indexes were highly individual. The drop in peak EPOC-values between 1st and 2nd halves probably originates from the depletion of the glycogen. Also it can be speculated that the characteristics of the match and the tactics of the team influence the stressfulness of the players. Especially this can be seen as low peak EPOC-values in match 3, where a red card was given to one of the opponent players after 23 minutes of play. The measuring system seems to work well in team sports like soccer in controlling the stressfulness of training and matches and the level of overall stress especially when the results are interpreted individually. REFERENCES [1] Hynynen E., Uusitalo A., Konttinen N. & Rusko H. (2007). Int J Sports Med DOI /s [2] Pichot, V., Roche, F., Gaspoz, J.-M., Enjolras, F., Antoniadis, A., Minini, P., Costes, F., Busso, T., Lacour, J.-R. & Barthélémy, J.C. (2000). Med Sci Sports Exerc 32: [3] Uusitalo, A.L.T. (2001). Phys Sportsmed 29: Verona-Ghirada Team Sport Conference, Treviso, Italy,

9 4 YHTEENVETO Sykemittauksiin perustuva kuormituksen ja palautumisen arviointijärjestelmä toimii jalkapallossa varsin hyvin. Pelin ja harjoitusten aikaisilla mittauksilla voidaan seurata eri pelaajien kuormittumista hyvin. Tietojen avulla voidaan myös suunnata maajoukkuetapahtumien ulkopuolista harjoittelua vastaamaan pelipaikan aiheuttamia vaatimuksia. Tallentavien sykepantojen avulla yömittaukset onnistuvat varsin hyvin ja pelaajien palautumistilatietojen avulla voitiin maajoukkuetapahtumien kuormitusta säädellä sopivaksi. Joukkueet kokivat tapahtumien aikana saadun mittauspalautteen tukevan toimintaa. Valmentajat pystyivät analysoimaan harjoitusten ja pelien kuormittavuutta ja lisäksi muokkaamaan tulevien harjoitusten kuormittavuutta pelaajien palautumistilatietojen mukaan. Lisämittauksia ja -kokemuksia kuitenkin tarvitaan, jotta joukkueet voisivat hyödyntää sykeseurantaa vielä paremmin toimintansa kehittämisessä. Sykeseurannoissa tulosten luotettavampi arviointi vaatii vielä pidempiaikaista yksilöllistä seurantaa. Näin saataisiin tietoa sekä urheilijoiden tilasta lepopäivän/-jakson jälkeisinä öinä että todella rankkojen harjoitusjaksojen jälkeisinä öinä. Nyt voi olla, että näillä mittausjaksoilla kuormitus ei kaikilla urheilijoilla ollut fyysisesti ja psyykkisesti todella kuormittavaa tai toisaalta urheilijat eivät olleet missään vaiheessa hyvin palautuneessa tilassa. Ääritilanteista saadut vertailutiedot mahdollistaisivat vielä paremman kuormitustilojen arvioinnin. Tulosten arviointi kannattaa tehdä yksilötasolla, koska eri pelaajien kuormitus samoissa harjoituksissa/otteluissa voi olla hyvinkin erilainen. Kokonaisuudessaan voidaan sanoa, että tämä projekti auttoi joukkueita. Valmentajat ja urheilijat saivat uutta tietoa eri menetelmistä ja kokemuksia niiden käytöstä. Naisten maajoukkue jatkaakin menetelmän käyttöä valmistautumisessa kohti vuoden 2009 EM-kisoja.

10 LÄHDELUETTELO Furlan, R., Piazza, S., Dell Orto, S., Gentile, E., Cerutti, S., Pagani, M. & Malliani, A. (1994). Early and late effects of exercise and athletic training on neural mechanisms controlling heart rate. Cardiovasc. Res. 27: Hynynen, E., Hämäläinen, I., Jylhä, R., Liukkonen, J., Nummela, A. & Rusko, H. (2006). Maastohiihdon kuormitusseurannan kehittämisprojekti vuoteen 2006 / Torino. KIHUn julkaisusarja nro 2. Kilpaja huippu-urheilun tutkimuskeskus KIHU, Jyväskylä. Hynynen E., Uusitalo A., Konttinen N. & Rusko H. (2007). Cardiac Autonomic Responses to Standing Up and Cognitive Task in Overtrained Athletes. Int J Sports Med DOI /s Häyrinen, M., Hynynen, E., Nummela, A., Savikko, H., Silander, J., Hakala, L., Berruto, M., Tolonen, T. & Honkanen, P. (2007). Kuormittumisen ja palautumisen seurantajärjestelmän kehittäminen lento- ja koripallossa. KIHUn julkaisusarja nro 8. Kilpa- ja huippu-urheilun tutkimuskeskus KIHU, Jyväskylä. Luhtanen P., Nummela A. & Lipponen K. (2007). Physical loading, stress and recovery in a youth soccer tournament. VI World Congress on Science and Football, Antalya , J Sports Sci Med, Vol. 6, Supplementum 10, pp Martinmäki, K., Rusko, H., Kooistra, L., Kettunen, J. & Saalasti, S. (2005). Intraindividual Validation of Heart Rate Variability Indices to Measure Vagal Effects on the Heart. Am J Physiol Heart Circ Physiol doi: /ajpheart Mourot, L., Bouhaddi, M., Perrey, S., Cappelle, S., Henriet, M-T., Wolf, J-P., Rouillon, J-D. & Regnard, J. (2004). Decrease in heart rate variability with overtraining: assessment by the Poincaré plot analysis. Clin Physiol Funct Imaging 24: Nummela, A., Vänttinen, T., Hynynen, E., Finni, J., Jouste, P., Keränen, T., Luhtanen, P., Mets, T., Mononen, K., Mäkelä, I., Norvapalo, K., Rusko, H., Salonen, M., Toivonen, R. & Tummavuori, M. (2006). Jalkapallon, yleisurheilun teholajien ja kivääriammunnan kuormitus- ja palautumiskonseptien kehittäminen. KIHUn julkaisusarja nro 6. Kilpa- ja huippu-urheilun tutkimuskeskus KIHU, Jyväskylä. Pichot, V., Roche, F., Gaspoz, J.-M., Enjolras, F., Antoniadis, A., Minini, P., Costes, F., Busso, T., Lacour, J.-R. & Barthélémy, J.C. (2000). Relation between heart rate variability and training load in middle-distance runners. Med Sci Sports Exerc 32: Rietjens, G.J.W.M., Kuipers, H., Adam, J.J., Saris, W.H.M., van Breda, E., van Hamont, D. & Keizer, H.A. (2005). Physiological, Biochemical and Psychological Markers of Strenuous Training- Induced Fatigue. Int J Sports Med 26: Tummavuori M. Hyvinvointianalyysi. Sykevälimittaus paljastaa harjoittelun vaikutukset. Valmentaja 2005: 2: 5 7. Uusitalo, A.L.T. (2001). Overtraining - a big challenge for top athletics. Phys Sportsmed 29: