Background:The Vpeak and its tlim are variables used to prescribe training loads and the intervals durations during interval training, respectively. The aim of this study was to
compare three running protocols to determine the tlim at Vpeak with warm-ups of 5, (tlim5), 10 (tlim10) and 15 (tlim15) minutes and the responses of physiological variables (heart rate (HR) and blood
lactate) and rating of perceived exertion (RPE) during the tests.
Methods:Fifteen healthy and physically active male were submitted to the following laboratory evaluations: A) anthropometric measurements; B) an incremental exercise test on treadmill
running starting with a speed of 8 km·h-1, after a warm-up of walking at 6 km·h-1 for three minutes, and increased by 1 km·h-1 between each successive 3-minute stage until volitional exhaustion to
determine Vpeak; at the end of each stage the HR and RPE were registered and earlobe capillary blood samples were collected to determine lactate concentrations pre-test and at the third and fifth
minutes post-test; C) three rectangular tests, performed in randomized order, with warm-up durations of 5, 10 and 15 minutes at 60% of Vpeak to determine the tlim5, tlim10 e tlim15; after the warm-up
the tests were performed at the speed of the individual Vpeak until volitional exhaustion. At the end of the warm-up and at each minute during the tests the HR and RPE were registered and blood
samples were collected pre-test, at the end of the test, 3, 5 and 7 minutes after the tests.
Results:Characteristics of the participants (mean ± SD) were: age 22.7 ± 3.0 years, height 1.8 ± 0.1 m, body mass 80.5 ± 9.5 kg, body mass index 24.9 ± 2.7 kg·m-2 and body fat 15.7 ±
5.7%. The variables obtained during the maximal incremental test to determine the Vpeak (mean ± SD) were: Vpeak=13.01 ± 1.1 km·h˗1, test duration=18.3 ± 3.4 min, maximal HR (HRmax)=192 ± 7.1 bpm, peak
RPE (RPEpeak)=19 ± 0.8 and peak lactate (LApeak)=8.8 ± 3.3 mmol·L-1. It was demonstrated that the duration of the warm-up affected the time test duration (tlim), in which the durations were: 7.7 ± 2.0
min for tlim5, 7.5 ± 1.7 min for tlim10 and 5.9 ± 1.7 min for tlim15; it was found differences between tlim5 and tlim15 and between tlim10 and tlim15; however, the tlim15 and tlim10 did not differ.
Additionally, the duration of the warm-up did not influence other variables (HRmax, RPEmax and post lactate concentrations). The HR values were significantly different after the warm-up between tlim15
and tlim5 and between tlim10 and tlim5 (P=0.001), which did not occur between tlim15 and tlim10. The RPE values after the warm-up were different between tlim15 and tlim10 and between tlim15 and tlim5.
Conclusions:Therefore, it was concluded that the duration of the warm-up in the tlim tests modifies the test duration, in which these differences imply considerations for the use of
this variable for training prescription.