Abstract
Minimising carbohydrate (CHO) status in the peri-training period may accelerate the
training adaptations normally observed. The aim of this study was to compare adaptations
to endurance training undertaken in the acutely CHO fed and overnight-fasted states.
Eight female and six male untrained, healthy participants: aged 26.6 ± 5.8 years (mean ± SD); height 174.7 ± 7.6 cm; weight 75.3 ± 11.4 kg; VO2max 3.48 ± 0.67 l/min; were randomly divided into two training groups and undertook four weeks of
five days per week endurance cycle ergometer training in either the overnight-fasted
(FAST) or acutely fed (FED) state. FAST training had no effect on RER or plasma glucose,
lactate and FFA concentrations during subsequent submaximal exercise. Training-induced
changes in Vastus lateralis citrate synthase (CS) and 3-hydroxy-CoA dehydrogenase (HAD) activities were not different
between training groups (P = 0.655 and 0.549, respectively), but when the effect of gender was considered, men
responded better to FAST and women responded better to FED. The FAST group showed
a significantly greater training-induced increase in VO2max and resting muscle glycogen concentration than FED (P = 0.014 and P = 0.047 respectively), but there was no gender interaction. In conclusion, these results
suggest that (a) meal ingestion prior to daily exercise can modify some of the exercise
training-induced adaptations normally seen with endurance training compared to when
daily exercise is undertaken in the overnight-fasted state; and (b) the extent of
these adaptations in skeletal muscle differ slightly between men and women.
Keywords
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Article info
Publication history
Published online: May 10, 2010
Accepted:
March 17,
2010
Received in revised form:
December 21,
2009
Received:
February 11,
2009
Identification
Copyright
© 2010 Sports Medicine Australia. Published by Elsevier Inc. All rights reserved.
