ORIGINAL ARTICLES   

The Journal of Sports Medicine and Physical Fitness 1999 December;39(4):282-4

Copyright © 2000 EDIZIONI MINERVA MEDICA

language: English

Resting serum antioxidant status is positively correlated with peak oxygen uptake in endurance trained runners

Child R. B., Wilkinson D. M., Fallowfield J. L.

Exercise Physiology Research Group, Centre for Sport Sciences, University College Chichester, College Lane, Chichester, UK

Background. This ­study test­ed the hypoth­e­sis ­that the abil­ity to scav­enge ­free rad­i­cals in ser­um was com­pro­mised in ­trained run­ners.
Methods. Experimental ­design: peak V.O2, the abil­ity to scav­enge ­free rad­i­cals in ser­um and the plas­ma con­cen­tra­tion of mal­on­di­al­de­hyde (MDA) ­were ­assessed in 18 ­male run­ners. Participants: subject char­ac­ter­is­tics (­mean±SEM) ­were ­height 1.77±0.01 m, ­mass 71.4±1.2 kg, age 31±1 ­years and week­ly train­ing dis­tance 45±5 km.­week-1. Measures: venous ­blood sam­ples ­were col­lect­ed at ­rest. Serum ­total anti­ox­i­dant capac­ity (TAC) was deter­mined ­using a chem­ilu­mi­nes­cent tech­nique. This ­involved the oxi­da­tion of lumi­nol, in a reac­tion cat­a­lysed by horse­rad­ish per­ox­i­dase. Serum anti­ox­i­dant pro­tec­tion was quan­ti­fied rel­a­tive to a sol­u­ble vita­min E ana­logue (Trolox) and ­expressed as Trolox equiv­a­lents (Trolox Eq.). MDA was deter­mined ­using a high­ly spe­cif­ic ­assay, ­using ­HPLC ­with flu­o­ri­met­ric detec­tion. Peak V.O2 was deter­mined from expired gas measurements collected during an incremental running test on a motorised treadmill. Data ­were ana­lysed ­using Pearson cor­re­la­tions.
Results. Serum TAC was 500±26 µmol Trolox Eq.l-1, ­with
a plas­ma MDA con­cen­tra­tion of 1.5±0.1 ­mmol.l-1 and
ser­um ­urate con­cen­tra­tion of 274±12 ­mmol.l-1. Peak V.O2 was 63±1 ml.kg-1.min-1. Significant cor­re­la­tions ­were ­observed ­between ­peak V.O2 and ser­um TAC (r=0.365, p<0.05); ­peak V.O2 and ser­um ­urate (r=0.463, p<0.05) and ser­um ­urate and ser­um TAC (r=0.807, p<0.001). Plasma MDA and ser­um TAC ­were not sig­nif­i­cant­ly cor­re­lat­ed (r=0.026, p>0.05).
Conclusions. These ­data dem­on­strate ­that the abil­ity to ­quench ­free rad­i­cals in ser­um is ­increased in rela­tion to the max­i­mum abil­ity to con­sume oxy­gen, how­ev­er ­this ­response ­does not ­appear to pro­vide any addi­tion­al pro­tec­tion ­against per­ox­i­da­tive dam­age ­at rest.