Abstract
The objective of this study was to determine the effects of high-intensity warm-ups
(WUs) on performance, physiological, neuromuscular and biomechanical parameters. Three
randomized cross-over 105%vVO2max time limit trials (TLimT) were performed by 11 well-trained runners following
three different WU protocols. These included two experimental high-intensity variants
and one control WU variant: (i) 9x20-sec level strides (105%vVO2max; 1% gradient) with 60 s of recovery (level); (ii) 6x6-sec uphill strides (105%vVO2max; 5% gradient), with the same recovery (uphill) and (iii) 7 min at 60%vVO2max as control condition (control). The uphill and level WUs resulted in a greater
performance during TLimT (160.0±6.62 s and 152.64±10.88 s, respectively) compared
to control WUs (144.82±6.60 s). All WU conditions reduced the energy cost (EC) of
running, respiratory exchange ratio, and step frequency (SF) after the experimental
and control phases of WU, while blood lactate (BLC) increased in uphill and level
WUs and decreased in control WUs. Changes in kinematic variables were found without
differences between WU conditions during TLimT. BLC rose at conclusion of TLimT without
differences between WU conditions. Both high-intensity WUs show a longer TLimT. EC
is deteriorated after the high-intensity WU exercise due to a change of substrate
utilization, increase of BLC and SF. A long transient phase (18 min) is necessary
to avoid impairing the performance.
Key words
energy systems - running economy - pre-exercise - stiffness - priming