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Abstract: Daub, BD, McLean, BD, Heishman, AD, Peak, KM, and Coutts, AJ. The relationship between mental fatigue and shooting performance over the course of a National Collegiate Athletic Association Division I basketball season. J Strength Cond Res 38(2): 334-341, 2024-The aim of this investigation was to examine the presence of mental fatigue and concurrent changes in shooting performance across various experimental weeks throughout a National Collegiate Athletic Association (NCAA) basketball season. Fifteen elite male NCAA Division I collegiate basketball players (age 20.2 ± 1.2 years, height 199.3 ± 7.1 cm, and body mass 93.1 ± 8.6 kg) volunteered for this study. Mental fatigue and basketball shooting performance was evaluated at 4 timepoints with varying seasonal demands: high game volume (GAME), high academic load (ACADEMIC), no games and no academic load (PRACTICE), and standard number of games and academic requirements (TYPICAL). Subjective mental fatigue increased significantly ( p ≤ 0.05) from Pre to Post brief psychomotor vigilance test (PVT-B) measurements at the end of the ACADEMIC week ( p = 0.002, d = 1.51) and from beginning to end of the ACADEMIC week ( p < 0.001, d = 2.21). Ratings of mental effort were significantly increased during the ACADEMIC week ( p < 0.001, d = 1.67). Recovery stress questionnaire (REST-Q) showed significant differences between week GAME and ACADEMIC with an increase in Social Stress ( p = 0.001, d = 0.84), Fatigue ( p = 0.021, d = 1.12), Disturbed Breaks ( p = 0.024, d = 0.57), and Emotional Exhaustion ( p = 0.035, d = 0.75). Lower shooting performance was observed during the ACADEMIC week from Pre to Post ( p = 0.009, d = 0.35) and higher scores Pre to Post in the TYPICAL week ( p = 0.008, d = 0.25). Basketball shooting performance was significantly reduced after increased levels of mental fatigue stemming from added academic stress. In addition, an increase in sport-specific training or games had no effect on subsequent basketball shooting performance. Special consideration should be given by coaches around examination periods because the existence of academic stressors can influence basketball shooting performance., (Copyright © 2023 National Strength and Conditioning Association.)

Abstract: Heishman, AD, Daub, BD, Miller, RM, Freitas, EDS, and Bemben, MG. Longitudinal hydration assessment in collegiate basketball players over various training phases. J Strength Cond Res 35(4): 1089-1094, 2021-To the best of our knowledge, previous literature has not longitudinally examined hydration status in collegiate basketball players. Therefore, the purpose of this investigation was to examine the prepractice hydration status of collegiate basketball players across various training phases for 2 consecutive years. Retrospective analyses examined prepractice urine-specific gravity (USG) assessments obtained from National Collegiate Athletic Association (NCAA) Division I male basketball players during the preseason and competitive season, for 2 consecutive years. The first year (year 1 = Y1) of analysis consisted of 15 athletes and the second year (year 2 = Y2) consisted of 16 athletes, with 8 athletes in both seasons. Hydration status was classified based on the National Athletic Trainers' criteria: (a) euhydrated, USG < 1.020; (b) hypohydrated, USG = 1.020-1.030; and (c) significantly hypohydrated, USG > 1.030. Additional comparisons examined the association of minutes played with hydration status and changes in hydration status for athletes returning from Y1 to Y2. The results indicated 55-65.7% of cases showed levels of significant hypohydration during the preseason and competitive seasons for both years. Preseason hydration status was significantly better than the competitive season (Y1, p = 0.008; Y2, p = 0.005). Despite significant differences in minutes played (p < 0.001), no differences in hydration status were observed. Returning athletes displayed no differences in hydration status between Y1 and Y2. Collegiate basketball players show levels of hypohydration when longitudinally examined across various training phases. Although hydration may be improved in the preseason, alternative factors such as average game minutes played and length in program may not influence hydration status., (Copyright © 2018 National Strength and Conditioning Association.)

Stone, BL, Heishman, AD, and Campbell, JA. The effects of an experimental vs. traditional military training program on 2-mile run performance during the army physical fitness test. J Strength Cond Res 34(12): 3431-3438, 2020-The purpose of this study was to compare the effects of an experimental vs. traditional military run training on 2-mile run ability in the Army Reserve Officers' Training Corps cadets. Fifty college-aged cadets were randomly placed into 2 groups and trained for 4 weeks with either an experimental running program (EXP, n = 22) comprised rating of perceived exertion (RPE) intensity-specific, energy system-based intervals or with traditional military running program (TRA, n = 28) using a crossover study design. A 2-mile run assessment was performed just before the start, at the end of the first 4 weeks, and again after the second 4 weeks of training after crossover. The EXP program significantly decreased 2-mile run times (961.3 ± 155.8 seconds to 943.4 ± 140.2 seconds, p = 0.012, baseline to post 1), whereas the TRA group experienced a significant increase in run times (901.0 ± 79.2 vs. 913.9 ± 82.9 seconds) over the same training period. There was a moderate effect size (d = 0.61, p = 0.07) for the experimental run program to "reverse" the adverse effects of the traditional program within the 4-week training period (post 1 to post 2) after treatment crossover. Thus, for short-term training of military personnel, RPE intensity-specific running program comprising aerobic and anaerobic system development can enhance 2-mile run performance superior to a traditional program while reducing training volume (60 minutes per session vs. 43.2 minutes per session, respectively). Future research should extend the training period to determine efficacy of this training approach for long-term improvement of aerobic capacity and possible reduction of musculoskeletal injury.

Miller, RM, Heishman, AD, Freitas, EDS, and Bemben, MG. Evaluating the effects of underloaded and overloaded warm-ups on subsequent swing velocity. J Strength Cond Res 34(4): 1071-1077, 2020-Several attempts to identify the optimal on-deck procedure to enhance swing velocity in baseball have been made. However, inconsistent findings continue to constitute much of the body of literature. In addition, the emergence of athlete monitoring in sport has led to the exploration of more sport-specific tasks to potentially identify athlete fatigue and readiness to perform. Therefore, the purpose of this investigation was to examine 3 different bat weight warm-up protocols on subsequent swing velocity and to examine the reliability of swing velocity measurements to allude to its potential a sport-specific athlete monitoring metric. Thirty-two recreational male baseball players 20.3 ± 2.0 years, 179.6 ± 7.1 cm and 89.6 ± 11.1 kg completed the study. Subjects completed 3 testing visits that included warming up with a control bat ([CB] 32 in., 29 oz), plastic bat ([PB] 31 in., 6.4 oz), or heavy bat ([HB] 32 in., 57 oz). Testing visits began with 3 CB swing trials followed by 3 intervention bat trials, then concluded with 3 additional CB swings. Swing velocity was assessed using visual 3D technology. Analyses of variance indicate that after the PB (26.6 ± 2.0 m·s) and CB interventions (26.2 ± 1.7 m·s) significantly faster (p < 0.001) swing velocities were generated when compared with the traditional HB intervention (24.1 ± 2.2 m·s). When assessed for reliability, the average ICC was 0.681 and Cronbach's alpha was 0.95, indicating exceptional reliability. Congruent to previous research, these data bolster the notion that warming up with a HB can hinder swing velocity. However, in contrast to previous research these data suggest that using a PB can increase swing velocity significantly. Furthermore, visual 3D can be designated as an exceptionally reliable device to measure swing velocity.

Heishman, AD, Daub, BD, Miller, RM, Freitas, EDS, Frantz, BA, and Bemben, MG. Countermovement jump reliability performed with and without an arm swing in NCAA Division 1 intercollegiate basketball players. J Strength Cond Res 34(2): 546-558, 2020-The countermovement jump (CMJ) is routinely used in athlete performance to quantify adaptions to training, as well as monitor neuromuscular readiness and fatigue. However, controversy remains in whether to incorporate an arm swing during the CMJ (CMJ AS) or keep the hands placed on the hips (CMJ NAS). Incorporating the arms provides a higher degree of sport-specificity that may yield improved reliability, especially in skilled jumpers. By contrast, the hands-on-hips approach isolates lower extremity force production and eliminates potential arm-swing variation. Therefore, the purpose of this study was to establish the reliability of CMJ typical (CMJ-TYP), CMJ concentric alternative (CMJ-Conc-ALT), and CMJ eccentric alternative (CMJ-Ecc-ALT) variables obtained during the CMJ AS and CMJ NAS. Twenty-two (men = 14, women = 8) NCAA Division 1 collegiate basketball players performed 3 CMJ AS and 3 CMJ NAS on a force plate, in a randomized order. To assess the test-retest reliability, participants returned 1 week later to perform 3 additional CMJ AS and 3 CMJ NAS. Intraclass correlation coefficient (ICC) and coefficient of variation (CV) were used to assess intersession and intrasession reliability for the various CMJ variables. A majority of CMJ-TYP and several CMJ-Conc-ALT and CMJ-Ecc-ALT variables exhibited adequate intersession and intrasession reliability (ICC > 0.700 and CV <10%) during both the CMJ AS and the CMJ NAS. Countermovement jump AS may provide more pertinent information about long-term changes in sport-specific performance, whereas the CMJ NAS may be more beneficial for detecting acute changes in neuromuscular fatigue and athlete readiness.

Miller, RM, Freitas, EDS, Heishman, AD, Koziol, KJ, Galletti, BAR, Kaur, J, and Bemben, MG. Test-retest reliability between free weight and machine-based movement velocities. J Strength Cond Res 34(2): 440-444, 2020-Several devices are available to measure muscular power through velocity measurement, including the Tendo FitroDyne. The ability for such devices to produce consistent results is still questioned, and the reproducibility of measurement between free weight and machine exercise has yet to be examined. Therefore, the aim of this investigation was to determine the test-retest reliability for barbell velocity during the bench press (BP) and weight velocity during the 2 leg press (2LP) for loads corresponding to 20-80% of 1 repetition maximum (1RM). Forty recreationally active individuals (22.6 ± 2.5 years; 175.9 ± 10.8 cm; and 76.2 ± 13.2 kg) with a 1RM BP and 2LP of 66.8 ± 32.4 kg and 189.5 ± 49 kg, respectively, volunteered for this study. Subjects completed 1 familiarization visit preceding 3 testing visits, which encompassed 1RM determination and 2 days of velocity testing. Forty-eight hours after 1RM testing, the subjects performed 1 repetition at 20, 30, 40, 50, 60, 70, and 80% of their 1RM for each exercise in randomized order. Subjects returned to the laboratory 1 week later to perform the velocity assessment again in randomized order. Intraclass correlation coefficient (ICC2,1) and relative SEM for the BP and 2LP ranged from 0.56 to 0.98 (3-18.1%) and 0.78 to 0.98 (2.8-7.2%), respectively, and no mean differences were observed between trials. The results suggest high reliability for BP velocity between 30 and 60% 1RM and moderate reliability at 20, 70, and 80% 1RM, while the 2LP displayed high to excellent reliability from 20 to 80% 1RM. Cumulatively, machine-based exercise displayed greater reproducibility; however, additional machine exercises need to be examined to bolster this conclusion.

Miller, RM, Keeter, VM, Freitas, EDS, Heishman, AD, Knehans, AW, Bemben, DA, and Bemben, MG. Effects of blood-flow restriction combined with postactivation potentiation stimuli on jump performance in recreationally active men. J Strength Cond Res 32(7): 1869-1874, 2018-Whole-body vibration (WBV) and maximum voluntary contractions (MVCs) combined with blood-flow restriction (BFR) to augment postactivation potentiation have yet to be examined. Therefore, the purpose of this investigation was to examine the augmented effects of postactivation potentiation when WBV and MVC are combined with BFR. Twenty men (21.8 ± 2.6 years, 180.5 ± 6.2 cm and 84.5 ± 12.1 kg) completed the study. Participants completed 3 testing sessions in a randomized design that included one of the following: (a) control (CON), (b) WBV and WBV combined with BFR (WBV + BFR), or (c) MVC and MVC combined with BFR (MVC + BFR). Jump height and power were recorded for 3 trials, PRE and POST jump height (cm) mean ± SD for each were as follows: CON 58.9 ± 8.6 and 57.9 ± 8.6, WBV 58.2 ± 8.1 and 59.9 ± 8.1, WBV + BFR 58.7 ± 7.6 and 60.2 ± 8.1, MVC 59.7 ± 7.4 and 60.2 ± 8.6, and MVC + BFR 57.7 ± 7.9 and 59.4 ± 8.1. PRE and POST jump power (W) mean ± SD for each were as follows: CON 1,224.3 ± 221.5 and 1,234.3 ± 189.2, WBV 1,251.1 ± 230.4 and 1,266.1 ± 215.7, WBV + BFR 1,265.8 ± 207.9 and 1,259 ± 223.3, MVC 1,264.7 ± 211.9 and 1,263.5 ± 236.5, and MVC + BFR 1,252.3 ± 222.0 and 1,294.6 ± 256.6. Significant differences were revealed in jump height between the 5 interventions (p < 0.01), WBV (p < 0.01), WBV + BFR (p < 0.01), and MVC + BFR (p < 0.01) revealed significant differences in time but no differences in jump power. In conclusion, the results of this study indicate that WBV, WBV + BFR, and MVC + BFR significantly improve jump height and time in air but not jump power.

Heishman, AD, Curtis, MA, Saliba, E, Hornett, RJ, Malin, SK, and Weltman, AL. Noninvasive assessment of internal and external player load: implications for optimizing athletic performance. J Strength Cond Res 32(5): 1280-1287, 2018-Few data exist that assess athlete tracking and monitoring for the development of strategies to optimize performance and reduce fatigue in elite athletes. The purpose of the present study was to assess the efficacy of external load and internal stress monitoring as assessment tools for examining a performance index of fatigue. A retrospective analysis was performed on data collected over the course of the preseason in 10 elite male NCAA Division 1 basketball players. Internal stress was assessed using Omegawave Technology readiness scores and compared with the performance index of countermovement jump (CMJ). The external load that accumulated during the previous practice, quantified by PlayerLoad (PL; Catapult), was compared with CMJ values and Omegawave scores. The results indicated that high, compared to low CNS Omegawave Readiness Scores (6.7 ± 05.1, 4.5 ± 1.2 AU; p < 0.001), were associated with increased CMJ (62.1 ± 6.5 vs. 59.4 ± 6.6 cm; p = 0.05), Power (6,590 ± 526.7 vs. 6,383.5 ± 606.8 W; p = 0.05), Omegawave Overall Readiness (5.8 ± 1.1 vs. 5.0 ± 0.7 AU; p = 0.05), and Omega Potential (Omega) (21.3 ± 6.3 vs. 9.9 ± 20.8 mV; p = 0.07). An increased PL during the previous exposure was associated with decreased CMJ (58.7 ± 4.7 cm vs. 60.4 ± 5.1 cm; p < 0.001) and increased TRIMP (135.1 ± 35.9 vs. 65.6 ± 20.0 AU; p < 0.001), and duration (115.4 ± 27.1 vs. 65.56 ± 20.0 minutes; p = < 0.001) despite no differences in Omegawave CNS Readiness scores. We conclude that Omegawave and Catapult technologies provide independent information related to performance and may be effective tools for monitoring athlete performance.

Time of day is a key factor that influences the optimization of athletic performance. Intercollegiate coaches oftentimes hold early morning strength training sessions for a variety of factors including convenience. However, few studies have specifically investigated the effect of early morning vs. late afternoon strength training on performance indices of fatigue. This is athletically important because circadian and/or ultradian rhythms and alterations in sleep patterns can affect training ability. Therefore, the purpose of the present study was to examine the effects of morning vs. afternoon strength training on an acute performance index of fatigue (countermovement jump height, CMJ), player readiness (Omegawave), and self-reported sleep quantity. We hypothesized that afternoon training sessions would be associated with increased levels of performance, readiness, and self-reported sleep. A retrospective analysis was performed on data collected over the course of the preseason on 10 elite National Collegiate Athletic Association Division 1 male basketball players. All basketball-related activities were performed in the afternoon with strength and conditioning activities performed either in the morning or in the afternoon. The average values for CMJ, power output (Power), self-reported sleep quantity (sleep), and player readiness were examined. When player load and duration were matched, CMJ (58.8 ± 1.3 vs. 61.9 ± 1.6 cm, p = 0.009), Power (6,378.0 ± 131.2 vs. 6,622.1 ± 172.0 W, p = 0.009), and self-reported sleep duration (6.6 ± 0.4 vs. 7.4 ± 0.25 p = 0.016) were significantly higher with afternoon strength and conditioning training, with no differences observed in player readiness values. We conclude that performance is suppressed with morning training and is associated with a decrease in self-reported quantity of sleep.