Vol. 7, No 2, 2009 pp. 181- 187
UDC 796.012.11:572.08
Original empirical article
POSTURAL SWAY AND CARDIORESPIRATORY RESPONSE TO RESISTANCE EXERCISES
Erika Zemková, Dušan Hamar
Department of Sports Kinanthropology, Faculty of Physical Education and Sport, Comenius University, Bratislava, Slovakia
E-mail: zemkova@yahoo.com
Abstract. The study compares parameters of balance after different forms of resistance exercise and after voluntary hyperventilation. A group of 22 physical education students performed 20 squats, calf raises, biceps curls, and presses behind the neck with an additional load of 50 % 1 RM. Besides this, they hyperventilated for a time corresponding to the duration of the exercises. Thirty seconds prior to and two minutes after the exercises the velocity of the centre of pressure was registered at 100 Hz by means of a posturography system FiTRO Sway Check based on force platform. While exercising and standing on the platform, parameters of ventilation and heart rate were continuously monitored using a breath-by-breath system MMC Horizon Sensormedics. The results showed the highest increase in velocity of the centre of pressure after squats (16.4 ± 1.4 mm/s), followed by calf raises (15.2 ± 1.3 mm/s), voluntary hyperventilation (14.8 ± 1.2 mm/s), biceps curls (14.0 ± 1.1 mm/s), and presses behind the neck (13.6 ± 0.8 mm/s). Similarly, the highest ventilation was found after squats (59.1 ± 6.6 l/min), then after calf raises (48.2 ± 5.8 l/min), voluntary hyperventilation (44.1 ± 5.2 l/min), biceps curls (40.0 ± 4.6 l/min), and presses behind the neck (38.9 ± 3.8 l/min). In addition, the heart rate was the highest after squats (165.0 ± 7.2 beats/min), following by calf raises (135.0 ± 6.8 beats/min), biceps curls (129.2 ± 5.8 beats/min), presses behind the neck (125.1 ± 4.6 beats/min), and voluntary hyperventilation (117.2 ± 4.8 beats/min). Furthermore, a significant (p ≤ 0.01) increase to a pre-exercise level in all of the parameters (8.6 ± 0.2 mm/s, 12.3 ± 0.1 l/min, and 76.5 ± 1.8 beats/min, respectively) has been found. During the phase of recovery, there was a close correlation between sway velocity and ventilation after squats (r = 0.939), calf raises (r = 0.919), biceps curls (r = 0.896), and presses behind the neck (r = 0.889). It may be concluded that a more marked ventilation rather than fatigue is responsible for an impairment of balance after resistance exercises.
Key words: Fatigue, hyperventilation, postural stability, resistance exercises
IZMENE U TEŽIŠTU TELA I KARDIO-RESPIRATORNI ODGOVOR NA TRENIRANJE SA DOZIRANIM OPTEREĆENJEM
Ovo istraživanje poredi parametre održavanja ravnoteže nakon različitih vrsti treniranja sa opterećenjem i nakon hiperventilacije. Ukupno 22 studenta fizičkog vaspitanja radilo je 20 čučnjeva, istezanje listova, vežbe za bicepse i potisak iza vrata sa dodatnim optrećenjem od 50 % 1 RM. Pored toga, podvrgli su se hiperventilaciji koja je trajala koliko i vežbe. Trideset sekundi pre i dva minuta nakon vežbi brzina težišta tela merena je na 100 Hz uz pomoć FiTRO Sway Check sistema za merenje držanja tela koji se bazira na platformi za delovanje sile. Dok su vežbali i stajali na platformi, parametri za ventilaciju i brzina otkucaja srca su se neprekidno merili uz pomoć dah-po-dah MMC Horizon Sensormedics sistema. Rezultati su pokazali da je porast sile težišta tela najveći nakon čučnjeva (16.4 ± 1.4 mm/s), zatim istezanja listova (15.2 ± 1.3 mm/s), hiperventilacije (14.8 ± 1.2 mm/s), vežbi za bicepse (14.0 ± 1.1 mm/s), i potiska iza vrata (13.6 ± 0.8 mm/s). Takođe, najveće vrednosti hiperventilacije zabeležene su nakon čučnjeva (59.1 ± 6.6 l/min), zatim nakon istezanja listova (48.2 ± 5.8 l/min), hiperventilacije (44.1 ± 5.2 l/min), vežbi za bicepse (40.0 ± 4.6 l/min), i potiska iza vrata (38.9 ± 3.8 l/min). Pored toga, brzina otkucaja srca bila je najveća nakon čučnjeva ats (165.0 ± 7.2 beats/min), zatim istezanja listova (135.0 ± 6.8 beats/min), vežbi za bicepse (129.2 ± 5.8 beats/min), potiska iza vrata (125.1 ± 4.6 beats/min), i hiperventilacije (117.2 ± 4.8 beats/min). Dalje, značajan porast (p ≤ 0.01) na nivo pre početka vežbanja je utvrđen za sve parametre (8.6 ± 0.2 mm/s, 12.3 ± 0.1 l/min, i 76.5 ± 1.8 otkucaja/min, tim redosledom). Tokom faze oporavka, javila se jaka korelacija između brizine izmene težišta tela i ventilacije nakon čučnjeva (r = 0.939), istezanja listova (r = 0.919), vežbi za bicepse (r = 0.896), i potiska iza vrata (r = 0.889). Možemo zaključiti da je jača ventilacija pre nego umor odgovorna za poteškoće u očuvanju težišta tela nakon trenirana sa opterećenjem.
Ključne reči: umor, hiperventilacija, stabilno držanje tela, vežbe sa opterećenjem