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Thiago S. Duarte, Danilo L. Alves, Danilo R. Coimbra, Bernardo Miloski, João C. Bouzas Marins and Maurício G. Bara Filho

Purpose: To analyze the technical and tactical training load in professional volleyball players, using subjective internal training load (session rating of perceived exertion  [SRPE]) and objective internal training load (training impulse of the heart rate [HR]) and the relationship between them. Methods: The sample was composed of 15 male professional volleyball players. They were monitored during 37 training sessions that included both technical (n = 23) and tactical (n = 14) training. Technical and training load was calculated using SRPE and training impulse of the HR. Results: Significant correlations were found between the methods in tactical (r = .616) and technical training (r = −.414). Furthermore, it was noted that technical training occurs up to 80% of HRmax (zone 3) and tactical training between 70% and 90% of HRmax (zones 3–4). Conclusions: The training impulse of the HR method has proved to be effective for training-load control during tactical training. However, it was limited compared with technical training. Thus, the use of SRPE is presented as a more reliable method in the different types of technical training in volleyball.

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Alba Reguant-Closa, Margaret M. Harris, Tim G. Lohman and Nanna L. Meyer

Nutrition education visual tools are designed to help the general population translate science into practice. The purpose of this study was to validate the Athlete’s Plate (AP) to ensure that it meets the current sport nutrition recommendations for athletes. Twelve registered dietitians (RDs; 10 female and 2 male) volunteered for the study. Each registered dietitian was asked to create three real and virtual plates at three different times corresponding to breakfast, lunch, and dinner, and the three different AP training loads, easy (E), moderate (M), and hard (H), divided into two weight categories (male 75 kg and female 60 kg). Data of the real and virtual plates were evaluated using Computrition software (v. 18.1; Computrition, Chatsworth, CA). Statistical analyses were conducted by SPSS (version 23.0; IBM, Armonk, NY) to compare the difference between each training load category (E, M, and H) and the recommendations. No statistically significant differences were found among the created plates and the recommendations for energy, carbohydrates, fat, and fiber for E, M, and H. Protein relative to body mass (BM) was higher than recommended for E (1.9 ± 0.3 g·kg−1 BM·day−1, p = .003), M (2.3 ± 0.3 g·kg−1 BM·day−1, p < .001), and H (2.9+0.5 g·kg−1 BM·day−1, p < .001). No differences were found for the macronutrient distribution by gender when correcting for kilograms of body mass. The authors conclude that the AP meets the nutrition recommendations for athletes at different training intensities for energy, carbohydrates, fat, and fiber, but exceeds the recommendations for protein. Further research should consider this protein discrepancy and develop an AP model that meets, besides health and performance goals, contemporary guidelines for sustainability.

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Paul F.J. Merkes, Paolo Menaspà and Chris R. Abbiss

Purpose: To determine the validity of the Velocomp PowerPod power meter in comparison with the Verve Cycling InfoCrank power meter. Methods: This research involved 2 separate studies. In study 1, 12 recreational male road cyclists completed 7 maximal cycling efforts of a known duration (2 times 5 s and 15, 30, 60, 240, and 600 s). In study 2, 4 elite male road cyclists completed 13 outdoor cycling sessions. In both studies, power output of cyclists was continuously measured using both the PowerPod and InfoCrank power meters. Maximal mean power output was calculated for durations of 1, 5, 15, 30, 60, 240, and 600 seconds plus the average power output in study 2. Results: Power output determined by the PowerPod was almost perfectly correlated with the InfoCrank (r > .996; P < .001) in both studies. Using a rolling resistance previously reported, power output was similar between power meters in study 1 (P = .989), but not in study 2 (P = .045). Rolling resistance estimated by the PowerPod was higher than what has been previously reported; this might have occurred because of errors in the subjective device setup. This overestimation of rolling resistance increased the power output readings. Conclusion: Accuracy of rolling resistance seems to be very important in determining power output using the PowerPod. When using a rolling resistance based on previous literature, the PowerPod showed high validity when compared with the InfoCrank in a controlled field test (study 1) but less so in a dynamic environment (study 2).

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Aaron T. Scanlan, Robert Stanton, Charli Sargent, Cody O’Grady, Michele Lastella and Jordan L. Fox

Purpose: To quantify and compare internal and external workloads in regular and overtime games and examine changes in relative workloads during overtime compared with other periods in overtime games in male basketball players. Methods: Starting players for a semiprofessional male basketball team were monitored during 2 overtime games and 2 regular games (nonovertime) with similar contextual factors. Internal (rating of perceived exertion and heart-rate variables) and external (PlayerLoad and inertial movement analysis variables) workloads were quantified across games. Separate linear mixed-models and effect-size analyses were used to quantify differences in variables between regular and overtime games and between game periods in overtime games. Results: Session rating-of-perceived-exertion workload (P = .002, effect size 2.36, very large), heart-rate workload (P = .12, 1.13, moderate), low-intensity change-of-direction events to the left (P = .19, 0.95, moderate), medium-intensity accelerations (P = .12, 1.01, moderate), and medium-intensity change-of-direction events to the left (P = .10, 1.06, moderate) were higher during overtime games than during regular games. Overtime periods also exhibited reductions in relative PlayerLoad (first quarter P = .03, −1.46, large), low-intensity accelerations (first quarter P = .01, −1.45, large; second quarter P = .15, −1.22, large), and medium-intensity accelerations (first quarter P = .09, −1.32, large) compared with earlier periods. Conclusions: Overtime games disproportionately elevate perceptual, physiological, and acceleration workloads compared with regular games in starting basketball players. Players also perform at lower external intensities during overtime periods than earlier quarters during basketball games.

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Samuel T. Orange, James W. Metcalfe, Ashley Robinson, Mark J. Applegarth and Andreas Liefeith

Purpose: To compare the effects of velocity-based training (VBT) vs percentage-based training (PBT) on strength, speed, and jump performance in academy rugby league players during a 7-wk in-season mesocycle. Methods: A total of 27 rugby league players competing in the Super League U19s Championship were randomized to VBT (n = 12) or PBT (n = 15). Both groups completed a 7-wk resistance-training intervention (2×/wk) that involved the back squat. The PBT group used a fixed load based on a percentage of 1-repetition maximum (1-RM), whereas the VBT group used a modifiable load based on individualized velocity thresholds. Biomechanical and perceptual data were collected during each training session. Back-squat 1-RM, countermovement jump, reactive strength index, sprint times, and back-squat velocity at 40–90% 1-RM were assessed pretraining and posttraining. Results: The PBT group showed likely to most likely improvements in 1-RM strength and reactive strength index, whereas the VBT group showed likely to very likely improvements in 1-RM strength, countermovement jump height, and back-squat velocity at 40% and 60% 1-RM. Sessional velocity and power were most likely greater during VBT compared with PBT (standardized mean differences = 1.8–2.4), while time under tension and perceptual training stress were likely lower (standardized mean differences = 0.49–0.66). The improvement in back-squat velocity at 60% 1-RM was likely greater following VBT compared with PBT (standardized mean difference = 0.50). Conclusion: VBT can be implemented during the competitive season, instead of traditional PBT, to improve training stimuli, decrease training stress, and promote velocity-specific adaptations.

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Niall Casserly, Ross Neville, Massimiliano Ditroilo and Adam Grainger

Purpose: The well-being of elite rugby union players has been intensely scrutinised in recent years. Understanding the longitudinal development of physical traits in junior players, alongside the moderating effect of simultaneous increases in body mass, can aid in improving programming and ultimately help junior players prepare for the demands of senior rugby. The purpose of this study was to investigate the longitudinal physical development of elite adolescent backs and forwards in a professional rugby union academy. Methods: A total of 15 players (age, 17.0 [0.2] y; body mass, 90 [14] kg; height, 183 [9] cm; n = 7 backs, n = 8 forwards) completed anthropometric measures and 3 primary performance assessments (countermovement jump, Yo-Yo intermittent recovery test level 1, and 10-m speed) at baseline, year 2, and year 3. Mixed modelling was used to assess player development over time and differences in this development by playing position. Magnitude-based inferencing was used to assess the uncertainty in the effects. Results: There was a substantial increase in countermovement jump height for both groups combined (0.9, ±0.4; standardized improvement, ±90% confidence limits; most likely substantial). Forwards exhibited a moderate-sized decrease in speed (−1.0, ±0.5; very likely substantial), and there was a large difference between groups with regards to speed change with backs outperforming forwards (1.5, ±0.9; very likely substantial). For forward, body mass change had a large negative association with 10-m speed (−1.9, ±0.7; most likely substantial) and Yo-Yo intermittent recovery test level 1 change (−1.2, ±0.9; very likely substantial). Conclusion: These findings provide novel normative data for longitudinal changes in junior rugby union players and suggest that coaches should account for changes in body mass when targeting increases in speed and aerobic fitness.

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Guillaume P. Ducrocq, Thomas J. Hureau, Olivier Meste and Grégory M. Blain

Context: Drop jumps and high-intensity interval running are relevant training methods to improve explosiveness and endurance performance, respectively. Combined training effects might, however, be achieved by performing interval drop jumping. Purpose: To determine the acute effects of interval drop jumping on oxygen uptake (V˙O2)—index of cardioventilatory/oxidative stimulation level and peripheral fatigue—a limiting factor of explosiveness. Methods: Thirteen participants performed three 11-minute interval training sessions during which they ran 15 seconds at 120% of the velocity that elicited maximal V˙O2 (V˙O2max) (ITrun), or drop jumped at 7 (ITDJ7) or 9 (ITDJ9) jumps per 15 seconds, interspersed with 15 seconds of passive recovery. V˙O2 and the time spent above 90% of V˙O2max (V˙TO2max) were collected. Peripheral fatigue was quantified via preexercise to postexercise changes in evoked potentiated quadriceps twitch (ΔQT). Power output was estimated during ITDJs using optical sensors. Results: All participants reached 90% of V˙O2max or higher during ITrun and ITDJ9, but only 11 did during ITDJ7. V˙TO2max was not different between ITrun and ITDJ9 (145 [76] vs 141 [151] s; P = .92) but was reduced during ITDJ7 (28 [26] s; P = .002). Mean ΔQT in ITDJ9 and ITDJ7 was not different (−17% [9%] vs −14% [8%]; P = .73) and greater than in ITrun (−8% [7%]; P = .001). No alteration in power output was found during ITDJs (37 [10] W·kg−1). Conclusion: Interval drop jumping at a high work rate stimulated the cardioventilatory and oxidative systems to the same extent as interval running, while the exercise-induced increase in fatigue did not compromise drop jump performance. Interval drop jumping might be a relevant strategy to get concomitant improvements in endurance and explosive performance.

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Blake D. McLean, Kevin White, Christopher J. Gore and Justin Kemp

Purpose: There is debate as to which environmental intervention produces the most benefit for team sport athletes, particularly comparing heat and altitude. This quasi-experimental study aimed to compare blood volume (BV) responses with heat and altitude training camps in Australian footballers. Methods: The BV of 7 professional Australian footballers (91.8 [10.5] kg, 191.8 [10.1] cm) was measured throughout 3 consecutive spring/summer preseasons. During each preseason, players participated in altitude (year 1 and year 2) and heat (year 3) environmental training camps. Year 1 and year 2 altitude camps were in November/December in the United States, whereas the year 3 heat camp was in February/March in Australia after a full exposure to summer heat. BV, red cell volume, and plasma volume (PV) were measured at least 3 times during each preseason. Results: Red cell volume increased substantially following altitude in both year 1 (d = 0.67) and year 2 (d = 1.03), before returning to baseline 4 weeks postaltitude. Immediately following altitude, concurrent decreases in PV were observed during year 1 (d = −0.40) and year 2 (d = −0.98). With spring/summer training in year 3, BV and PV were substantially higher in January than temporally matched postaltitude measurements during year 1 (BV: d = −0.93, PV: d = −1.07) and year 2 (BV: d = −1.99, PV: d = −2.25), with year 3 total BV, red cell volume, and PV not changing further despite the 6-day heat intervention. Conclusions: We found greater BV after training throughout spring/summer conditions, compared with interrupting spring/summer exposure to train at altitude in the cold, with no additional benefits observed from a heat camp following spring/summer training.

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Carl Foster, Jos J. de Koning, Christian Thiel, Bram Versteeg, Daniel A. Boullosa, Daniel Bok and John P. Porcari

Background: Pacing studies suggest the distribution of effort for optimizing performance. Cross-sectional studies of 1-mile world records (WRs) suggest that WR progression includes a smaller coefficient of variation of velocity. Purpose: This study evaluates whether intraindividual pacing used by elite runners to break their own WR (1 mile, 5 km, and 10 km) is related to the evolution of pacing strategy. We provide supportive data from analysis in subelite runners. Methods: Men’s WR performances (with 400-m or 1-km splits) in 1 mile, 5 km, and 10 km were retrieved from the IAAF database (from 1924 to present). Data were analyzed relative to pacing pattern when a runner improved their own WR. Similar analyses are presented for 10-km performance in subelite runners before and after intensified training. Results: WR performance was improved in 1 mile (mean [SD]: 3:59.4 [11.2] to 3:57.2 [8.6]), 5 km (13:27 [0:33] to 13:21 [0:33]), and 10 km (28:35 [1:27] to 28:21 [1:21]). The average coefficient of variation did not change in the 1 mile (3.4% [1.8%] to 3.6% [1.6%]), 5 km (2.4% [0.9%] to 2.2% [0.8%]), or 10 km (1.4% [0.1%] to 1.5% [0.6%]) with improved WR. When velocity was normalized to the percentage mean velocity for each race, the pacing pattern was almost identical. Very similar patterns were observed in subelite runners in the 10 km. When time improved from 49:20 (5:30) to 45:56 (4:58), normalized velocity was similar, terminal RPE increased (8.4 [1.6] to 9.1 [0.8]), coefficient of variation was unchanged (4.4% [1.1%] to 4.8% [2.1%]), and VO2max increased (49.8 [7.4] to 55.3 [8.8] mL·min−1·kg−1). Conclusion: The results suggest that when runners break their own best performances, they employ the same pacing pattern, which is different from when WRs are improved in cross-sectional data.

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Irineu Loturco, Timothy Suchomel, Chris Bishop, Ronaldo Kobal, Lucas A. Pereira and Michael R. McGuigan

Purpose: To identify the bar velocities that optimize power output in the barbell hip thrust exercise. Methods: A total of 40 athletes from 2 sports disciplines (30 track-and-field sprinters and jumpers and 10 rugby union players) participated in this study. Maximum bar-power outputs and their respective bar velocities were assessed in the barbell hip thrust exercise. Athletes were divided, using a median split analysis, into 2 groups according to their bar-power outputs in the barbell hip thrust exercise (“higher” and “lower” power groups). The magnitude-based inferences method was used to analyze the differences between groups in the power and velocity outcomes. To assess the precision of the bar velocities for determining the maximum power values, the coefficient of variation (CV%) was also calculated. Results: Athletes achieved the maximum power outputs at a mean velocity, mean propulsive velocity, and peak velocity of 0.92 (0.04) m·s−1 (CV: 4.1%), 1.02 (0.05) m·s−1 (CV: 4.4%), and 1.72 (0.14) m·s−1 (CV: 8.4%), respectively. No meaningful differences were observed in the optimum bar velocities between higher and lower power groups. Conclusions: Independent of the athletes’ power output and bar-velocity variable, the optimum power loads frequently occur at very close bar velocities.