Komparativna studija izmjerenog i procijenjenog vo2max u višestupanjskom funkcionalnom testu pripremljenosti nogometaša juniora

The multi-stage 20-m shuttle run test (MSRT) is one of the most popular field tests using equations based on test results or the final speed for an indirect estimation of maximal oxygen uptake (VO2max). The aim of this study was to compare the real VO2max value to the predicted value of VO2max by MSRT and rate the usefulness of the MSRT as a predictor of VO2max in young football players. Fifteen young football players, nominees for the 2004/2005 national Under-18 team, were included in this study. The subjects were 17.9±.2 years old, had an average height of 178.8±7 cm and an average weight of 71.8±7.5 kg. The players came from different Slovenian junior premier football league clubs and trained on average 4 to 5 times per week. Testing was conducted on all subjects over two days, between 9 a.m. and 2 p.m., on synthetic turf. A mobile device for the measurement of O2 and CO2 in expired air and ventilation during MSRT was used. On the basis of the test result (the number of levels and repetitions between them) VO2max was calculated. The correlation between the measured and predicted VO2max was determined with Pearson’s correlation coefficient. The comparison of both mean values showed that the measured value was significantly higher (p<.05), by as much as 8.5 ml O2 kg-1•min-1, than the MSRT-predicted VO2max. Variables were statistically correlated, but the correlation coefficient amounted to only .58. This study has shown that an indirect evaluation of aerobic capacity based on the multi-stage 20 m shuttle run test can lead to wrong conclusions in young soccer players. The correlation observed between the measured and predicted VO2max was too weak to predict the aerobic capacity of young football players with certainty.Višestupanjski test povratnog trčanja dionica od 20 metara (MSRT) je jedan od najpopularnijih terenskih testova koji koriste jednadžbe za procjenu maksimalnog primitka kisika (VO2max) na temelju ukupnog rezultata testa ili konačne brzine trčanja na kraju testa. Cilj ovog istraživanja bio je usporediti stvarne vrijednosti VO2max s procijenjenim vrijednostima VO2max dobivenima pomoću MSRT te ocijeniti korisnost toga terenskog višestupanjskog testa kao prediktora VO2max u mladih nogometaša. U istraživanje je bilo uključeno 15 mladih nogometaša izabranih za slovensku nacionalnu selekciju U18 u sezoni 2004./2005. Ispitanici su bili u dobi od 17,9±0,2 godina, prosječne visine 178,8±7 cm i prosječne težine 71,8±7,5 kg. Igrači su bili članovi različitih slovenskih prvoligaških juniorskih klubova i trenirali su u prosjeku 4 do 5 puta tjedno. Testiranje je provedeno na svim ispitanicima tijekom dva dana, u vremenu između 9 i 14 sati na umjetnoj travi. Korišteni su prijenosni uređaji za mjerenje O2 i CO2 u izdahnutomu zraku i ventilacije tijekom provedbe MSRT. Na temelju rezultata testa (razina otkaza i broj ponavljanja unutar razine otkaza) izračunat je VO2max. Povezanost između izmjerenoga i procijenjenoga VO2max utvrđena je Pearsonovim koeficijentom korelacije. Usporedba prosječnih vrijednosti pokazala je da je izmjerena vrijednost VO2max bila statistički značajno viša (p<0,05) za 8,5 ml O2 kg-1•min-1 od procijenjene vrijednosti VO2max koja je izračunata pomoću MSRT. Korelacija između varijabli bila je statistički značajna, ali je korelacijski koeficijent bio samo 0,58. Ovo je istraživanje pokazalo da neizravno vrednovanje aerobnoga kapaciteta rezultatima u testu MSRT može dovesti do pogrešnih zaključaka na populaciji mladih nogometaša. Utvrđena povezanost između izmjerene i procijenjene vrijednosti VO2max bila je preslaba da bi sa sigurnošću mogla poduprijeti procjenu aerobnoga kapaciteta u mladih nogometaša

Komparativna studija izmjerenog i procijenjenog vo2max u višestupanjskom funkcionalnom testu pripremljenosti nogometaša juniora

The multi-stage 20-m shuttle run test (MSRT) is one of the most popular field tests using equations based on test results or the final speed for an indirect estimation of maximal oxygen uptake (VO2max). The aim of this study was to compare the real VO2max value to the predicted value of VO2max by MSRT and rate the usefulness of the MSRT as a predictor of VO2max in young football players. Fifteen young football players, nominees for the 2004/2005 national Under-18 team, were included in this study. The subjects were 17.9±.2 years old, had an average height of 178.8±7 cm and an average weight of 71.8±7.5 kg. The players came from different Slovenian junior premier football league clubs and trained on average 4 to 5 times per week. Testing was conducted on all subjects over two days, between 9 a.m. and 2 p.m., on synthetic turf. A mobile device for the measurement of O2 and CO2 in expired air and ventilation during MSRT was used. On the basis of the test result (the number of levels and repetitions between them) VO2max was calculated. The correlation between the measured and predicted VO2max was determined with Pearson’s correlation coefficient. The comparison of both mean values showed that the measured value was significantly higher (p<.05), by as much as 8.5 ml O2 kg-1•min-1, than the MSRT-predicted VO2max. Variables were statistically correlated, but the correlation coefficient amounted to only .58. This study has shown that an indirect evaluation of aerobic capacity based on the multi-stage 20 m shuttle run test can lead to wrong conclusions in young soccer players. The correlation observed between the measured and predicted VO2max was too weak to predict the aerobic capacity of young football players with certainty.Višestupanjski test povratnog trčanja dionica od 20 metara (MSRT) je jedan od najpopularnijih terenskih testova koji koriste jednadžbe za procjenu maksimalnog primitka kisika (VO2max) na temelju ukupnog rezultata testa ili konačne brzine trčanja na kraju testa. Cilj ovog istraživanja bio je usporediti stvarne vrijednosti VO2max s procijenjenim vrijednostima VO2max dobivenima pomoću MSRT te ocijeniti korisnost toga terenskog višestupanjskog testa kao prediktora VO2max u mladih nogometaša. U istraživanje je bilo uključeno 15 mladih nogometaša izabranih za slovensku nacionalnu selekciju U18 u sezoni 2004./2005. Ispitanici su bili u dobi od 17,9±0,2 godina, prosječne visine 178,8±7 cm i prosječne težine 71,8±7,5 kg. Igrači su bili članovi različitih slovenskih prvoligaških juniorskih klubova i trenirali su u prosjeku 4 do 5 puta tjedno. Testiranje je provedeno na svim ispitanicima tijekom dva dana, u vremenu između 9 i 14 sati na umjetnoj travi. Korišteni su prijenosni uređaji za mjerenje O2 i CO2 u izdahnutomu zraku i ventilacije tijekom provedbe MSRT. Na temelju rezultata testa (razina otkaza i broj ponavljanja unutar razine otkaza) izračunat je VO2max. Povezanost između izmjerenoga i procijenjenoga VO2max utvrđena je Pearsonovim koeficijentom korelacije. Usporedba prosječnih vrijednosti pokazala je da je izmjerena vrijednost VO2max bila statistički značajno viša (p<0,05) za 8,5 ml O2 kg-1•min-1 od procijenjene vrijednosti VO2max koja je izračunata pomoću MSRT. Korelacija između varijabli bila je statistički značajna, ali je korelacijski koeficijent bio samo 0,58. Ovo je istraživanje pokazalo da neizravno vrednovanje aerobnoga kapaciteta rezultatima u testu MSRT može dovesti do pogrešnih zaključaka na populaciji mladih nogometaša. Utvrđena povezanost između izmjerene i procijenjene vrijednosti VO2max bila je preslaba da bi sa sigurnošću mogla poduprijeti procjenu aerobnoga kapaciteta u mladih nogometaša

Effects of aerobic training on serum paraoxonase activity and its relationship with PON1-192 phenotypes in women

WOS: 000392924800018PubMed ID: 30356554Background: Paraoxonase 1 (PON1) is an antioxidant enzyme that protects high-density lipoprotein (HDL) and low-density lipoprotein against oxidation. Limited studies have addressed the influence of exercise on PON1 activity and its relationship with PON1 phenotypes. We investigated relationships between PON1-192 phenotypes, PON1 activity, aerobic exercise, and blood lipid and lipoprotein concentrations in middle-aged women. Methods: An exercise group (n = 50) engaging in regular aerobic exercise and a control group (n = 41) were selected from a subset of 300 Caucasian women that met the inclusion criteria. Serum PON1, salt-stimulated PON1 (SSPON1), and arylesterase (ARE) activities; cholesterol levels and ARE activities of total HDL and HDL subgroups (HDLs) (supernatants obtained by polyethylene glycol); and blood lipid and lipoprotein concentrations were determined by standardized enzymatic methods. PON1-192 QQ (low activity), QR (moderate activity), and RR (high activity) phenotype groups were defined using serum SSPON1/ARE activity ratios. The R-carries (RC) phenotype group consisted of the QR and RR groups combined. Results: All lipid and lipoprotein concentrations were greater in the exercise group than in the control group. Regardless of phenotype, no significant differences were observed between the exercise and control groups in terms of serum PON1, SSPON1, or ARE activity associated with HDLs (p > 0.05), whereas PON1 activities in QQ-phenotyped women in the exercise group were significantly higher than those in the control group (p < 0.01), but not the RC group. A statistically significant interaction between PON1 phenotypes (QQ and RC groups) and exercise (exercise and control groups) on PON1 activity was found. Conclusion: These results showed that a regular aerobic exercise program can improve PON1 activity depending on PON1-192 phenotype, but not on lipid and lipoprotein levels, in middle-aged Turkish women. (C) 2016 Production and hosting by Elsevier B.V. on behalf of Shanghai University of Sport. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).Ege University Scientific Research Projects DirectorateEge University [2006-BESYO-004]This study was supported by the Ege University Scientific Research Projects Directorate (2006-BESYO-004). The authors would like to express thanks to Drs. Zisan Cetinkalp and Ekim Pekunlu at the Ege University School of Physical Education and Sports for their assistance in statistical analysis