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The effects of plyometric training (PT) on middle- and long-distance running performances are well established. However, its influence on pacing behaviour is still unclear. The aim of this study was to evaluate the effects of PT on pacing behaviour. In addition, verify whether the adaptations induced by PT would change ratings of perceived exertion (RPE) and/or affective feelings during the race. Twenty-eight male runners were assigned to two groups: control (C) and PT. PT held two weekly PT sessions for eight weeks. Drop jump (DJ) performance, 10-km running performance, pacing behaviour, RPE and affective feelings, VO2peak, ventilatory thresholds (VT1 and VT2), peak treadmill speed (PTS), and running economy (RE) were measured. For group comparisons, a mixed model analysis for repeated measures, effect size (ES) and 90% confidence interval (90% CI) were calculated for all dependent variables. Significant differences pre-to-post was observed for PT group in DP (7.2%; p ≤ 0.01; ES = 0.56 (0.28–0.85)) and RE (4.5%; p ≤ 0.05; ES = −0.52 ((−0.73 to −0.31)) without changes in pacing behaviour. While PT was effective for improving DJ and RE, there is no evidence that pacing behaviour, RPE or affective feelings are directly affected by these adaptations during a 10-km time trial run. [ABSTRACT FROM AUTHOR]

The current study analysed the effect of distinct pacing profiles (i.e. U, J, and inverted J) in the perceptual responses and neuromuscular fatigue (NMF) development following a 4-km cycling time trial (TT). Twenty-one cyclists with similar training status were allocated into three different groups based on their pacing profile spontaneously adopted during TT. Rating of perceived exertion (RPE), oxygen uptake (⩒O2) and heart rate (HR) were continuously recorded. NMF was assessed by using isometric maximal voluntary contractions (IMVC), while the central [i.e. voluntary activation (VA)] and peripheral fatigue of knee extensors [i.e. peak torque of potentiated twitches (TwPt)] were evaluated using electrically evoked contractions performed pre and 2 min after the TT. TT performance was not different amongst pacing profiles (U = 377 ± 20 s; J = 392 ± 23 s; J-i = 381 ± 20 s) (all P > 0.05). RPE, ⩒O2 and HR increased similarly throughout the TT regardless the pacing strategy (all P > 0.05). Similarly, IMVC (U = −9.9 ± 8.8; J = −9.6 ± 4.5%; J-i = −13.8 ± 11.3%), VA (U = −2.3 ± 1.7%; J = −5.4 ± 2.2%; J-i = −6.4 ± 4.5%) and TwPt (U = −32.5 ± 12.0%; J = −29.5 ± 8.0%; J-i = −33.6 ± 13.6%) were similar amongst pacing profiles (all P > 0.05). Therefore, endurance athletes with similar training status showed the same perceived responses and NMF development regardless the pacing profile spontaneously adopted. It was suggested that these responses occurred in order to preserve a similar rate of change in systemic responses (i.e. RPE, ⩒O2 and HR) and NMF development, ultimately resulting in same TT performance. Different pacing profiles resulted in the same performance in a 4-km cycling time trial. The similar performance might be due to achievement of the same sensory tolerance limit. There was no difference for perceptual, metabolic and neuromuscular fatigue responses. [ABSTRACT FROM AUTHOR]