Comparative analysis of selected coordination indicators of cross-country skiing with classical technique and skating

125 COMPARATIVE ANALYSIS OF SELECTED COORDINATION INDICATORS OF CROSS-COUNTRY SKIING WITH CLASSICAL TECHNIQUE AND SKATING B onisla K ačma , *Ma ina Ch ás ko á **Radka Bačáko á, ***Vladimí Hojka Cha les Uni e si y in P ague Facul y o Physical Educa ion and Spo Jose Ma iho 31, 162 52 P aha 6 [email p o ec ed], *m[email p o ec ed], **[email p o ec ed], ***[email p o ec ed] Abs ac C oss-coun y skiing is ecommended as a pa o pos - ehabili a ion mo o egime. The gliding s ep in classical echnique and V-1 ska ing a e he mos common used echniques in he ec ea ional o m. The aim o he s udy was o clea ou how he mo o s e eo ype o c oss-coun y skiing co esponds wi h bipedal walking. The used me hods we e he synch onized ideo eco d wi h he su ace poly-elec omyog aphy in e ain (EMG). The da a we e in e p e ed on he basis o he compa a i e c oss-co ela ion analysis o ac i a ion s a s o he obse ed muscles. The emale skie compe ing in he na ional eam showed he simila i y o phase mo es o muscles s abilizing he pel is and knee join bo h du ing walking and c oss-coun y skiing (bo h echniques). The di e ence be ween c oss-coun y skiing and walking was ound in phase muscles aking pa on he p opulsi e s eng h o locomo ion. I was no possible o compa e he coo dina ion ela ionship o he ac i i y pai s: gliding s ep in classical echnique – walking and V-1 ska ing – walking. Keywo ds: c oss-coun y skiing, walking, elec omyog aphy. 1 Backg ound C oss-coun y skiing belongs among cyclic s eng h-endu ance spo s wi h he egula wo k o lowe and uppe limbs and unk muscles (Massaad e al, 2007). The e a e highe demands on agili y o shoulde and hip join s du ing c oss-coun y skiing (Ila ský, 2005). Acco ding o G ego y e al. and Vii asela e al. (G ego y e al., 1994, Vii asalo e al., 1997) di e ences in kinema ics o c oss-coun y skiing be ween mo e and less success ul compe i o s a e a ely published. The cause is obse ed in he high numbe o ac o s in luencing i . Pun um ixum is also c ea ed by uppe limbs du ing c oss-coun y skiing, as he skie was going back o quad upedal mo emen . In he shoulde gi dle we suppose muscle coo dina ion, which has i s equi alen in on ogene ic o ms o human locomo ion (Voj a, Pe e s 1995, K ačma , 2007). Thanks o e ical body posi ion he quad upedal cha ac e o locomo ion is unde s ood speci ically. Tha is gi en by he e ical body posi ion, which ini ia es he unc ion o body s abilizing sys em, which was no s a ed ye in he ho izon al body posi ion in he ea ly cou se o human mo emen on ogenesis in he phase o quad upedal locomo ion (Véle, 2006, K ačma , 2007). Simila ly, his phenomenon is unde s ood om he poin o iew o apes’ phylogeny by Vanča a (Vanča a, 2002). 126 Vys čilo á e al (Vys čilo á e al. 2007, Vys čilo á e al., 2008) conside he unc ion o m. la issimus do si as he main muscle in he unk a ea and plexus b achialis c ucial o human locomo ion ealized h ough he shoulde gi dle (c oss-coun y skiing, No dic walking, c awling, climbing, c awl s oke in swimming). The muscle g oups o unk and s omach e icien ly ans e s eng hs and s abilize unk (Wigge , 1998). The c oss-coun y skie needs he balance skill (Gnad, Pso o á, 2005). I enables o ealize ake-o and ollowing he longes possible slide on one leg (Ch ás ko á, 2009). Classical echnique de eloped g adually by making he slide longe when walking on skis and skis a e pa allel du ing he whole mo emen cycle. Locomo ion is ealized by al e na e wo k o uppe and lowe limbs, which is necessa y o con ol by neu o-muscula coo dina ion in a way he complex and con inuous mo emen was c ea ed (Ch ás ko á, 2009). Realiza ion o all mo emen s should hen be wi h he same equency, maximal laxa ion and luency. Figu e 1 shows he cou se o he gliding s ep mo emen . F ig. 1 The mo emen cou se du ing he gliding s ep in c oss-coun y skiing classical echnique The mo emen cycle o he gliding s ep can be di ided o: ake-o , weigh ans e , glide and a m wo k. This s yle is used mainly in skiing uphill, e en ually on he la e ain by less s eng h equipped indi iduals. Take-o is ealized om he ski skid when he ake-o ski is s opped. I is ealized by a g adual ex ension o knee, hip and inally ankle join s. The ake-o phase is inished by emo ing he ake-o ski om he su ace. The glide phase is longe han he ake-o phase. The posi ion o body’s cen e o g a i y is changed; he dynamic balance is ealized. The glide quali y depends on he e iciency o he p e ious ac i i y – he ake-o . I is also a p epa a ion o he nex ake-o . The skie ’s body mo es o “o e hang” – i is sligh ly leaned o wa d. The skie ge s o one-leg s and; only he gliding ski is ouching he su ace. The a m wo k is coo dina ed wi h lowe limbs. They co espond wi h each o he in he s ep s a phase and ake-o phase (Ila ský, 2005). F ee echnique – ska ing. Ska ing is mo e p og essi e in compa ison wi h classical echnique. The ake-o ski is placed on he snow in he V posi ion and hen u ned on he inne edge. The ake-o is ealized du ing he glide. Skiing is mo e luen and demands on ake-o iming a e no as high as in classical echnique. The ake-o om he inne ski edge is suppo ed by bo h poles push-o , which is mo e e icien han he al e na e push-o used in he gliding s ep (Gnad, Pso o á, 2005). Figu e 2 shows he mo emen cou se o V-1 ska ing. The ake-o s a s wi h a sligh ly bended knee and inishes wi h he g adually ex ended lowe limb. Fo he igh di ec ion o he ake-o and i s e icien use he unk is sligh ly bended o wa d. In he ake-o phase he unloaded leg is ac i ely ans e ed pas he ankle o he ake-o leg c ossways o wa d so i had in he momen o placing on snow i s ini ial speed in a glide; accele a ion is eached by ha . The unk is pe manen ly kep in a sligh lean o wa d (Ila ský, 2005). 127 V-1 ska ing wi h he asymme ical mo emen o a ms is he slowes ska ing. The e is only one push-o o bo h igh and le s eps o legs. V-1 ska ing wi h he asymme ical mo emen is he mos used ype o ska ing among wide popula ion. The skie does only one push-o and wo s eps wi h lowe legs. Be e skie s a e able o do he push-o on he igh o le side acco ding o e ain condi ions. This ska ing is used when he skie is less balanced du ing he glide on one ski. F ig. 2 The mo emen cou se o V-1 ska ing wi h asymme ical mo emen o a ms Ou s udy looked in o he le el o coo dina ion simila i y o bo h ypes o c oss-coun y skiing wi h he mo o s e eo ype o ee bipedal walking. Compa ison was ealized in he compe i ion skie , a membe o Czech na ional eam. I was he mos pe ec a ailable mo o s e eo ype conside ed by an expe . 2 Me hods In a-indi idual compa a i e analysis was ealized a he membe o junio Czech na ional eam in c oss-coun y skiing. 60 wo king (s ep) cycles du ing walking we e e alua ed, hen 60 cycles du ing he gliding s ep o he classical echnique and 60 cycles du ing V-1 ska ing. Measu ing was ealized on snow o a high quali y, in -8°C, on c oss-coun y acks in No é Měs o na Mo a ě. We ha e used he su ace poly-elec omyog aphy (De Luca, 1993) wi h he synch onized ideo eco d measu ed by he po able de ice on he basis o EMG, ca ied on he spo sman body: pa e ning 200 1.s-1, il a ion 29 Hz - 1200Hz wi h he ime in a iable τ = 0,04 s (Me le i, Pa ke , 2004). I had se en pai s o la elec odes wi h he diame e 7mm, dis ances o cen es we e 25mm, ea h connec ion and sa ing da a in o own memo y. See Vys čilo á e al. (Vys čilo á e al., 2008). 3 Resea ch design The case in a-indi idual compa a i e analysis s udied h ee di e en o ms o locomo ion. The a iable ha was no obse ed was locomo ion speed; he manipula ed a iable was a wo king (s ep) cycle du ing c oss-coun y skiing wi h he classical echnique, ska ing on skis and ee bipedal walking. E e y obse ed ac i i y was measu ed six imes in 20 seconds in e als wi h 3 minu es b eaks o ans e da a om he eco de o PC. 60 wo king cycles we e e alua ed om e e y ac i i y. We ha e measu ed muscles on igh side o he body in he pel is a ea and lowe limb. Fu he mo e, we ha e localized elec odes also con a la e ally on he muscle m. gas ocnemius sin, capu medialis. Table 1 shows he su ey o he obse ed muscles. 128 Tab. 1 Su ey o he obse ed muscles wi h se sensi i i y o scanning channels [mV] muscle channel sensi i i y [mV] locomo ion walking gliding s ep V-1 ska ing m.glu eus maximus dx 0,05 0,1 0,05 m. glu eus medius dx 0,2 2 1 as us medialis dx 0,05 0,2 0,1 m. gas ocnemius dx, cap. medialis 0,1 0,1 0,1 m. ibialis an e io dx 0,2 0,2 0,2 m. gas ocnemius sin, cap. medialis 0,2 0,2 0,2 EMG da a we e p ocessed in he Ma lab so wa e in o he o m o ma ices o c oss- co ela ion alues o phase shi s o decisi e muscle ac i a ion s a s. We ha e e alua ed he a e age wo king cycle (n=60) o e e y obse ed locomo ion ype. The s udy did no deal wi h he diagonal phenomenon and la e ali y in c ossed locomo ion pa e n. 4 Resul s Tables 2, 3, 4 s a e ma ices o c oss-co ela ion alues o phase shi s o decisi e muscle ac i a ion s a s o an a e age wo king cycle (n=60). The e e en ial muscle was chosen m. ibialis an e io dx. Tab. 2 Ma ix o c oss-co ela ion alues o phase shi s o decisi e muscle ac i a ion s a s o an a e age wo king cycle (n=60) du ing ee bipedal walking Phase shi o walking m.glu . max.dx m.glu . med.dx as . med.dx m.gas . dx cap.med. m. ib.an .dx m.gas . sin c.med m.glu .max.dx 0 38% 47% -34% 42% 17% m.glu .med.dx 0 0 4% -29% 5% -21% as .med.dx 0 0 0 27% -11% -30% m.gas .dx c,med. 0 0 0 0 -38% 47% m. ib.an .dx 0 0 0 0 0 -26% m.gas .sin c.med 0 0 0 0 0 0 Tab. 3 Ma ix o c oss-co ela ion alues o phase shi s o decisi e muscle ac i a ion s a s o an a e age wo king cycle (n=60) du ing he gliding s ep o he classical echnique in c oss-coun y skiing Phase shi o he gliding s ep m.glu . max.dx m.glu . med.dx as . med.dx m.gas . dx cap.med. m. ib.an .dx m.gas . sin c.med m.glu .max.dx 0 -1% 0% -4% 2% 46% m.glu .med.dx 0 0 2% -3% 2% -2% as .med.dx 0 0 0 -5% -1% 44% m.gas .dx c,med. 0 0 0 0 5% 49% m. ib.an .dx 0 0 0 0 0 45% m.gas .sin c.med 0 0 0 0 0 0 Tab. 4 Pha s ska m.gl m.gl as m.g a m. i b m.g a w 1 G aph 1 5 Di s The ol l  C w m M a ix o s a s o a mo emen s e shi o V ing u .max.dx u .med.dx .med.d x a s .dx c,me d b .an .dx a s .sin c.m e w alkin g 1 s ep cycle 1 EMG e c and V-1 s cussion l owing disc C oss-co e e e en ial w alking as m uscles o c oss-co e a n a e age w o a ms V -1 m. g ma x 0 0 0 d . 0 0 e d 0 c o d o he ska ing wi ussion is m e la ion al u muscle w a he do sa l he a e a g e la ion al u w o king cy c g lu . x .dx m. g me d 0 4 % 0 0 0 0 0 0 0 0 0 0 g liding s e 1 s ep cyc l selec ed w o h asymme m ainly base d u es o deci s a s chosen m l lexo o g e wo kin g u es o phas e c le (n=60) d g lu . d .dx a s med . % 1 % 0 1 % 0 0 0 0 0 0 0 0 e p l e o king cycl e ical mo e m d on: s i e muscl e m . ibialis a leg. W e g cycle (n = e shi s o d e d u ing V-1 s . . dx m.gas dx cap.m e % 4% % -13 % 0% 0 0 0 V 1 e o ee bip m en o a m s e ac i a io n an e io d x e desc ibe = 60) in he e cisi e mus c ska ing wi h . e d. m. ib.an 0% % 1% 0% 14 % 0 0 V -1 ska ing 1 s ep cycle edal walki n s n s a s (T a x . o i s s iming o in e al - 5 c le ac i a i o h asymme .dx m.gas sin c.me d -44 % -19 % -49 % % -48 % -22 % 0 n g, he glidi n a bles 2, 3, s peci ic u n he o he o 5 0% o +5 0 1 o n ical . d % % % % % n g s ep 4). The n c ion in o bse ed 0 %. The 29 130 posi ions o he ac i a ion s a o m. ibialis an e io dx. has he alue 0%. The low pe cen age alues mean he ime simila s a o decisi e muscle ac i a ion o wo conside ed muscles.  iming o local maximums o muscles (g aph 1), and  he a ea size unde he EMG cu e o he a e age wo king (s ep) cycle, which is a p obabili y quan i y and poin s o dynamics o muscle wo k quan i y. Phase shi s o M. glu eus maximus dx., on con a y o m. glu eus medius dx. (walking 38%, gliding s ep -1% and V-1 ska ing 4%) indica e a signi ican a ini y o c oss-coun y skiing compa ed o walking. The same can be ound in he ela ionship o his muscle o ou mo o ma ke m. ibialis an e io dx. (42%, 2%, and 0%). We could disc e ely conclude ha du ing c oss-coun y skiing m. ibialis an e io dx. ge s mo e in o he pos u al ole, oge he wi h m. glu eus medius dx. The cha ac e o EMG cu e p o es ha as well. In all ee ypes o locomo ion he muscles m. glu eus medius dx. and m. ibialis an e io dx. a e simila in muscle ac i a ion s a s, mo eo e , he ac i a ion s a is same in ska ing. Muscles m. ibialis an e io dx and m. glu eus medius dx. ha e e y simila s a o decisi e muscle ac i a ion (5%, 2%, and 1%) in all h ee o ms o locomo ion. He e we can alk abou e y simila coo dina ion ela ionships. These wo e y impo an muscles o walking show he mu ual close ela ionship among walking, he gliding s ep and V-1 ska ing. I esul s om bipedal o m o locomo ion, when he s ep s a phase and he pel is s abili y is kep in ans e sal le el. When compa ing muscle ac i a ion s a s o m. ibialis an e io dx. and m. gas ocnemius dx., capu medialis we ind he bigges di e ence in walking, when he i s named muscle p ecedes he o he by 38% o he wo king cycle, in he gliding s ep i ollows by 5% and in V- 1 ska ing e en by 14%. Thanks o hese big di e ences (be ween walking and he gliding s ep 43% and walking and V-1 ska ing 52%) we a he conside he speci ics o c oss-coun y skiing in gene al. This phenomenon is p obably in luenced by he mo e di icul keeping he on -back balance in a glide on one ski (do sal plan a sense o keeping he posi ion and mo emen ) on con a y o dynamic balance in one-leg s and when walking. In walking i is a he a mo emen (a g adual cou se o he highes s ess on he oo o wa d wi h he ollowing do sal lexion); meanwhile in c oss-coun y skiing he pos u al unc ion o he muscle ensu ing a he he posi ion is mo e ob ious he e. In c oss-coun y skiing in gene al he EMG cu e is again shakie ; i indica es he ecip ocal balancing he on -back posi ion o he oo . The g ea e po ion o pos u al unc ion is also p o ed by he g ea e po ion o “pos u al backg ound” o he EMG in ake. Cu es s ay on con a y o walking in places o hei local minimums on ela i ely highe ampli ude. F om he poin o iew o he a ea unde he EMG cu e, he e a e he highes demands on m. ibialis an e io dx. du ing he gliding s ep, he lowes du ing V-1 ska ing. The muscle m. gas ocnemius dx., capu medialis a e s essed in his sense in he o de : he gliding s ep, V-1 ska ing, walking. This muscle also ha e he highes alues o phase shi di e ences be ween c oss-coun y skiing in gene al and walking. The o de is again walking - gliding s ep - V-1 ska ing.  M. gas ocnemius dx, capu medialis s. m. glu eus maximus dx: -34%, -4%, 4%,  m. gas ocnemius dx, capu medialis s. m. glu eus medius dx: -29%, -3%, -13%,  m. gas ocnemius dx, capu medialis s. as us medialis dx: 27%, -5%, 0%,  m. gas ocnemius dx, capu medialis s. m. ibialis an e io dx: -38%, 5%, 14%. This phase muscle, which decisi e unc ion in human locomo ion is ealizing and inishing oo ake-o he su ace, shows he gene al di e ence o c oss-coun y skiing as one g oup ( he gliding s ep and V-1 ska ing) on con a y o walking on he o he side. The o he gene al di e ence o walking and c oss-coun y skiing shows he mu ual coo dina ion ela ionship o muscle ac i a ion s a s o m. glu eus maximus and as us 131 medialis. In walking we ind he phase co ela ion o 47% delay o as us medialis, in c oss- coun y unning 0% and 1%. Howe e , he knee s abilize as us medialis on con a y o walking has signi ican ly g ea e a ea unde he cu e in he gliding s ep, app oxima ely 200% and in V-1 ska ing e en app oxima ely 470%. This ac deno es c oss-coun y skiing in gene al as an ac i i y which signi ican ly s esses he knee s abilize as us medialis. Recommenda ion o pos - ehabili a ion egime hen accen s speci ically ska ing on skis. The iming o decisi e muscle ac i a ion s a s in he muscles as us medialis dx. and m. glu eus medius dx. is e y in e es ing. These wo muscles s a ac i a ion e y simila ly in walking and bo h ypes o c oss-coun y skiing ( alues 4%, 2%, 1%). Bo h hese muscles s abilizing hei co esponding s uc u e (knee, pel is) coope a e so in hei s abilizing unc ion in all ee ypes o locomo ion. I is possible o say ha om he poin o s abiliza ion c oss-coun y skiing (bo h he gliding s ep and V-1 ska ing) and walking e y simila . And ha is despi e he ac ha he s anding leg in walking goes h ough he suppo phase and s and on one place o he solid suppo and in c oss-coun y skiing his leg inds i sel in a glide. We may ouch he essence o c ea ing dynamic balance in one-leg suppo s and in c oss-coun y skiing. The pe ec ly lea ned echnique o c oss-coun y skiing has in i sel such a quali y o dynamic balance, which app oaches he balance o he s anding leg in walking, when he c ea ed poin o suppo (punc um ixum) does no mo e. The muscle m. ibialis an e io dx. inds i sel in coope a ion wi h bo h abo e men ioned s abilizing muscles - as us medialis dx. ( alue o he phase shi in he gliding s ep – 1%, in V-1 ska ing 0%) in c oss-coun y skiing in gene al, meanwhile i p ecedes (-11%) in walking. This si ua ion ela es o s ep dynamics. In walking he m. ibialis an e io d.x ac i a ion p ecedes oo ead, so a e he ead he obse ed s abilizing muscles we e ac i a ed ( as us medialis dx. and m. glu eus medius dx.). M. ibialis an e io dx. in compa ison wi h he o he s abilizing muscle m. glu eus medius dx. b ings alues o he phase shi 2% and 1% in c oss- coun y skiing, in walking he alue is 5%. This change o he phase shi in walking on he con a y o he pai m. ibialis an e io d. and as us medialis dx. (5% on con a y o -11%) ela es logically o keeping on -back posi ion on he gliding ski. Ou chosen “walking ma ke ”, m. ibialis an e io dx., in ela ion o he side pel is s abilize , m. glu eus medius dx. has simila phase shi s wi h li le essen ial di e ences in iming. Walking 5%, he gliding s ep 2%, V-1 ska ing 1%. This phenomenon again shows he kinesiology ela ionship o all h ee obse ed ypes o locomo ion. In he cou se o EMG cu e o m. ibialis an e io dx in he g aph 1 we can show signi ican local maximums in walking, phase cha ac e ized. The cu e cha ac e is mo e explosi e in bo h ypes o c oss- coun y skiing, he ampli ude does no decline o ze o ( onic backg ound), he muscle esponds o he equi emen o keeping pos u e in he egime o dynamic balance in a glide. Tables 2, 3, 4 also s a e phase shi s o he con a-la e al muscle m. gas ocnemius sin, capu medialis. The muscle inclusion in V-1 ska ing is no suppo ed by he wo k o shoulde gi dle and is no discussed la e . Compa ison wi h a simila esea ch abou he kinesiology con en o spo mo emen in c oss-coun y skiing is no possible as he e is no simila opic in Czech and o eign sou ces. Conclusion C oss-coun y skiing di e s om walking in gene al in iming o decisi e muscle ac i a ion s a mainly in phase muscles m. glu eus maximus dx., m. gas ocnemius dx., capu medialis s. as us medialis dx., m. ibialis an e io dx. The muscles wo king o s abiliza ion, such as m. glu eus medius dx. and as us medialis dx., wo k in a e y simila iming in walking and in c oss-coun y skiing in gene al. In m. ibialis an e io dx., ou chosen walking ma ke (explained abo e), we ha e ound he muscle pe sis ence in a ce ain onic ension in he a eas 132 o local minimums in c oss-coun y skiing, in walking he EMG eco d shows a mo e phase cou se. We ind signi ican ly g ea e a eas unde he EMG cu e in as us medialis dx. in c oss- coun y skiing. Fo he pos - ehabili a ion mo o egime we ind he use mo e in insu iciency o pel is s abiliza ion and a e knee join ope a ions. The muscle cha ac e is ics o ac i a ion o he obse ed s abilizing muscles app oach he cha ac e is ics o ee bipedal walking as he basic and also he na u al o m o human locomo ion. On he basis o measu emen s o ou selec ed muscles i is no possible o s a e, which o he obse ed ypes o c oss-coun y skiing is mo e ela ed o ee bipedal walking. The s a ed conclusions a e alid wi h ega d o he esea ch o m – he case s udy o he woman skie on a e y high pe o mance le el (Czech na ional eam) wi h high expe ly judged le el o coo dina ion. 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ISSN 1211–2658. ________________________________________________________ Doc. PaedD . B onisla K ačma , CSc., Mg . Ma ina Ch ás ko á, Mg . Radka Bačáko á, Mg . Vladimí Hojka