Vitamin E supplementation does not alter physiological performance at fixed blood lactate concentrations in trained runners.
OBJECTIVE
The aim of the study was to determine the direction of change in performance variables at fixed blood lactate concentrations following vitamin E (VE) supplementation.


METHODS
In a paired-matched design twelve (male: N.=8; female: N.=4) trained runners were allocated to a VE (N.=6; 268 mg·d⁻¹) or placebo (N.=6; glucose: 30 mg·d⁻¹) group for 35 days. Participants completed a discontinuous incremental exercise test, pre and post supplementation, to determine peak oxygen uptake (VO2peak) running velocity and percentage of peak oxygen uptake (%(VO2peak) at the lactate threshold (TLAC) and the onset of blood lactate accumulation (OBLA). Participants maintained a standardised training regime throughout the supplementation period.


RESULTS
VE supplementation failed to significantly enhance velocity at TLAC (P=0.91) and OBLA (P=0.22) compared to a placebo treatment. Analogously, VE did not significantly enhance %(VO2peak) at TLAC (P=0.85) and OBLA (P=0.71) compared to a placebo treatment. Whilst VE supplementation did not enhance performance it did not impair performance compared to a placebo. Training significantly enhanced velocity at TLAC (P=0.00) and OBLA (P=0.05). No training-induced improvements in %VO2peak at TLAC (P=0.06) and OBLA (P=0.40) were observed.


CONCLUSIONS
Daily VE supplementation for 35 days does not enhance or impair physiological performance at fixed blood lactate concentrations. Long-term VE supplementation for the purposes of performance enhancement is not recommended.
Sport and Exercise Research Group, Department of Sport and Physical Activity, Edge Hill University Ormskirk, Lancashire, UK.
J N
JN
Cobley
K
K
Marrin
D000975:Antioxidants / Q000008:administration & dosage*; D054874:Athletic Performance / Q000502:physiology*; D005260:Female; D006801:Humans; D019344:Lactic Acid / Q000097:blood*; D008297:Male; D010101:Oxygen Consumption / Q000502:physiology; D012420:Running / Q000502:physiology*; D016037:Single-Blind Method; D014810:Vitamin E / Q000008:administration & dosage*
D000975:Antioxidants; D014810:Vitamin E; D019344:Lactic Acid