Can plyometric training change the pacing behaviour during 10-km running?

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.

Self-selected Rest Interval Improves Vertical Jump Postactivation Potentiation.

ABSTRACT: do Carmo, EC, De Souza, EO, Roschel, H, Kobal, R, Ramos, H, Gil, S, and Tricoli, V. Self-selected rest interval improves vertical jump postactivation potentiation. J Strength Cond Res 35(1): 91-96, 2021-This study compared the effects of self-selected rest interval (SSRI) and fixed rest interval (FRI) strategies on postactivation potentiation (PAP) in countermovement jump (CMJ) performance. Twelve strength-trained men (age: 25.4 ± 3.6 years; body mass: 78.8 ± 10.5 kg; height: 175 ± 7.0 cm; half-squat 1 repetition maximum: 188.7 ± 33.4 kg) performed 3 experimental conditions: (a) FRI: CMJ test; 4-minute rest interval; 5 repetition maximum (5RM) back squat; 4-minute rest interval; and CMJ test, (b) SSRI: CMJ test; 4-minute rest interval; 5RM back squat; SSRI; and CMJ test, and (c) control: CMJ test; 8-minute rest interval and CMJ test. In SSRI, subjects were instructed to rest until they felt fully recovered and able to exercise at maximal intensity based on the perceived readiness scale. Significant changes in pre-post CMJ performance were observed in the SSRI condition (38.2 ± 4.6 cm vs. 40.5 ± 4.4 cm; p = 0.08; confidence interval [CI]: 0.72-3.82 cm; effect size [ES] = 0.93). There were significant differences in post-CMJ performance when SSRI was compared with FRI (40.5 ± 4.4 cm vs. 37.7 ± 5.1 cm; p = 0.02; CI: 0.43-5.08; ES = 1.13) and control (40.5 ± 4.4 cm vs. 37.4 ± 5.7 cm; p = 0.01; CI: 0.66-5.61; ES = 1.35). The average rest interval length for the SSRI condition was 5:57 ± 2:44 min:sec (CI: 4:24-7:30). Our results suggest that the use of SSRI was an efficient and practical strategy to elicit PAP on CMJ height in strength-trained individuals.

Affective Feelings and Perceived Exertion During a 10-km Time Trial and Head-to-Head Running Race.

PURPOSE: To verify the affective feelings (AFs) and rating of perceived exertion (RPE) responses during a 10-km competitive head-to-head (HTH) running race and compare them with a time-trial (TT) running race. METHODS: Fourteen male runners completed 2 × 10-km runs (TT and HTH) on different days. Speed, RPE, and AF were measured every 400 m. For pacing analysis, races were divided into the following 4 stages: first 400 m (F400), 401-5000 m (M1), 5001-9600 m (M2), and the last 400 m (final sprint). RESULTS: Improvement of performance was observed (39:32 [02:41] min:s vs 40:28 [02:55] min:s; P = .03; effect size = -0.32) in HTH compared with TT. There were no differences in either pacing strategy or RPE between conditions. AFs were higher during the HTH, being different in M2 compared with TT (2.09 [1.81] vs 0.22 [2.25]; P = .02; effect size = 0.84). CONCLUSIONS: AFs are directly influenced by the presence of opponents during an HTH race, and a more positive AF could be involved in the dissociation between RPE and running speed and, consequently, the overall race performance.

Influence of an Enforced Fast Start on 10-km-Running Performance.

The effects of an enforced fast start on long-distance performance are controversial and seem to depend on the athlete's capacity to delay and tolerate metabolic disruption. The aim of this study was to investigate the effects of an enforced start on 10-km-running performance and the influence of the some physiological and performance variables on the ability to tolerate an enforced fast start during the running. Fifteen moderately trained runners performed two 10-km time trials (TTs): free pacing (FP-TT) and fast start (FS-TT). During FS-TT, speed during the first kilometer was 6% higher than in FP-TT. Maximal oxygen uptake (VO2max), peak velocity (PV), velocity associated with VO2max (vVO2max), ventilatory threshold, and running economy at 10 and 12 km/h and FP-TT average velocity (AV-10 km) were individually determined. There were no differences between FP-TT and FS-TT performance (45:01 ± 4:08 vs 45:11 ± 4:46 min:s, respectively, P = .4). Eight participants improved (+2.2%) their performance and were classified as positive responders (PR) and 7 decreased (-3.3%) performance and were classified as negative responders (NR). Running speed was significantly higher for PR between 6 and 9.2 km (P < .05) during FS-TT. In addition, PR presented higher PV (P = .02) and vVO2max (P = .01) than NR, suggesting that PV and vVO2max might influence the ability to tolerate a fast-start strategy. In conclusion, there was an individual response to the enforced fast-start strategy during 10-km running, and those who improved performance also presented higher vVO2max and PV, suggesting a possible association between these variables and response to the strategy adopted.

The effects of training volume and repetition distance on session rating of perceived exertion and internal load in swimmers.

PURPOSE: To assess swimmers' session rating of perceived exertion (sRPE) after standardized sets of interval swimming training performed at the same relative intensity but with different total volume and repetition distance. METHODS: Thirteen moderately trained swimmers (21.1 ± 1.1 y, 178 ± 6 cm, 74.1 ± 8.3 kg, 100-m freestyle 60.2 ± 2.9 s) performed 4 standardized sets (10 × 100-m, 20 × 100-m, 10 × 200-m, and 5 × 400-m) at the same relative intensity (ie, critical speed), and 1 coach (age 31 y, 7 y coaching experience) rated their efforts. Swimmers' sRPE was assessed 30 min after the training session. Coach sRPE was collected before each training session. Internal load was calculated by multiplying sRPE by session duration. RESULTS: When bouts with the same repetition distance and different volumes (10 × 100-m vs 20 × 100-m) are compared, sRPE and internal load are higher in 20 × 100-m bouts. When maintaining constant volume, sRPE and internal load (20 × 100-m, 10 × 200-m, and 5 × 400-m) are higher only in 5 × 400-m bouts. The coach's and swimmers' sRPE differed in 10 × 200-m and 5 × 400-m. CONCLUSIONS: These results indicate that sRPE in swimming is affected not only by intensity but also by volume and repetition distance. In addition, swimmers' and the coach's sRPE were different when longer repetition distances were used during training sessions. Therefore, care should be taken when prescribing swimming sessions with longer volume and/or longer repetition distances.