Abstract Heilbronn, BE, Doma, K, Sinclair, WH, Drain, J, Connor, J, and Leicht, AS. Reliability and divergent validity of novel tools to assess occupationally relevant performance in infantry soldiers. J Strength Cond Res 39(6): e815–e823, 2025—The primary aim of this study was to determine the reliability and divergent validity of several weighted physical assessments for the Army, including the counter movement jump (CMJ), plyometric push-ups (PPU), an incremental fire and movement assessment (IMFA), and a repeated sprint ability (RSA) test. Male infantry soldiers (n = 30) completed the CMJ, PPU, IFMA, and RSA during both unweighted and weighted conditions with a 48-hour interval between sessions, and then repeated the tests during a weighted condition after a 7-day wash-out period. Intraclass correlation coefficient (ICC) and coefficient of variation (CV) assessed between-session reliability. Divergent validity between weighted and unweighted conditions was determined using Pearson's correlation coefficient (r), with correlation effect size (ES) calculated between the r-values using a Fisher Z-transformation. Good test-retest reliability and divergent validity were demonstrated for most CMJ (ICC 0.50–0.99, CV% 1.18–7.73, ES 0.50–0.69), PPU (ICC 0.61–0.99, CV% 1.03–12.33, ES 0.31–0.68), RSA (ICC 0.50–0.94, CV% 1.34–8.41, ES 0.37–0.75), and IFMA (ICC 0.65–0.94, CV% 2.80–10.99, ES 0.32–0.39) measures. It was concluded that the weighted CMJ, PPU, IMFA, and RSA were reliable tests for Army-specific fitness to determine combat task readiness. Good divergent validity between weighted and unweighted conditions for most test measures supported practitioner's use of weighted assessments for Army-specific capability, while unweighted assessments were recommended for fitness optimization and monitoring training for Army personnel.
ABSTRACT Harry, JR, Hurwitz, J, Agnew, C, and Bishop, C. Statistical tests for sports science practitioners: identifying performance gains in individual athletes. J Strength Cond Res 38(5): e264-e272, 2024-There is an ongoing surge of sports science professionals within sports organizations. However, when seeking to determine training-related adaptations, sports scientists have demonstrated continued reliance on group-style statistical analyses that are held to critical assumptions not achievable in smaller-sample team settings. There is justification that these team settings are better suited for replicated single-subject analyses, but there is a dearth of literature to guide sports science professionals seeking methods appropriate for their teams. In this report, we summarize 4 methods' ability to detect performance adaptations at the replicated single-subject level and provide our assessment for the ideal methods. These methods included the model statistic, smallest worthwhile change, coefficient of variation (CV), and standard error of measurement (SEM), which were discussed alongside step-by-step guides for how to conduct each test. To contextualize the methods' use in practice, real countermovement vertical jump (CMJ) test data were used from 4 (2 females and 2 males) athletes who complete 5 biweekly CMJ test sessions. Each athlete was competing in basketball at the NCAA Division 1 level. We concluded that the combined application of the model statistic and CV methods should be preferred when seeking to objectively detect meaningful training adaptations in individual athletes. This combined approach ensures that the differences between the tests are (a) not random and (b) reflect a worthwhile change. Ultimately, the use of simple and effective methods that are not restricted by group-based statistical assumptions can aid practitioners when conducting performance tests to determine athlete adaptations.
Abstract Kasahara, K, Konrad, A, Murakami, Y, Thomas, E, and Nakamura, M. Comparison of the effects of a roller massager intervention on the rectus femoris between lengthened and slack positions. J Strength Cond Res 38(11): 1879–1884, 2024—A roller massager (RM) is a type of foam rolling device, which previous studies have shown to be effective for acutely decreasing tissue hardness and increasing range of motion (ROM). However, these effects may differ with the RM intervention position (i.e., knee flexion or knee extension). Therefore, this study aimed to compare the acute effects of an RM intervention on the rectus femoris (RF) in the knee flexed and extended positions. The subjects were 14 healthy male college students (age, 22.6 ± 0.8 years). The RF of the dominant leg was tested. Three conditions were compared: a control condition with no intervention (CON), an RM intervention in knee extension (i.e., RM_extension), and a RM intervention in knee flexion (i.e., RM_flexion). The measurements were tissue hardness in the proximal (TH_pro), middle (TH_mid), and distal (TH_dis) portions of the RF, knee flexion ROM, pain pressure threshold (PPT), maximal voluntary isometric contraction (MVC-ISO) torque, and maximal voluntary concentric contraction (MVC-CON) torque in the RF before and immediately after the intervention. There were significant interaction effects of TH_mid and knee flexion ROM. Both RM_extension and RM_flexion conditions showed a significant (p < 0.01) decrease in TH_mid and an increase in knee flexion ROM, but there were no significant differences between conditions. There was a main effect for TH_pro and PPT (p < 0.05) but no significant interaction effect or main effect for TH_dis, MVC-ISO torque, and MVC-CON torque. The results showed that the RM intervention can effectively decrease tissue hardness and increase ROM, regardless of limb position (i.e., knee extension or flexion).
Abstract McMahon, G. No effect of interset palm cooling on acute bench press performance, neuromuscular or metabolic responses, following moderate-intensity resistance exercise. J Strength Cond Res 38(7): 1213–1220, 2024—Despite the growing literature in high-intensity exercise regarding palm cooling, the acute effects of palm cooling on exercise performance indices, neuromuscular and metabolic responses, have not been described during moderate-intensity resistance exercise. Nine (age, 22 ± 1 year; mass, 80.8 ± 16.2 kg; height, 1.80 ± 0.11 m) healthy, male (n = 7) and female (n = 2) resistance-trained subjects performed 4 sets of bench press to failure at 60% 1 repetition maximum with 3-minute passive recovery. Subjects were randomly allocated to either the cooling (COL; 2 minutes of cooling at 10 °C) or the control (passive rest; CON) condition separated by 1 week between the conditions. Exercise performance (volume load, repetitions, barbell velocity), muscle activation, blood lactate, and rate of perceived exertion were assessed. Despite changes across the variables during the resistance exercise sessions, there were no statistical differences (p > 0.05) in any of the performance, neuromuscular or physiological responses, between the 2 experimental conditions, despite palm temperature being significantly (p < 0.001) reduced in the cooling condition compared with control throughout. Therefore, based on the results of this study, palm cooling does not enhance acute moderate-intensity resistance exercise.
Abstract Racil, G, Padulo, J, Trabelsi, Y, Frizziero, A, Russo, L, and Migliaccio, GM. Rhythmic exercises before basketball training: A study on motor skills, static balance, and reaction speed in school-aged children. J Strength Cond Res 38(12): e761–e768, 2024—The aim of this study was to investigate the effects of combining rhythmic exercises with basketball training on the improvement of basic motor and physical skills in children. Thirty-four female subjects, all from the same secondary school and aged 12 ± 0.7 years, participated in a 6-week training program (3 times per week). They were randomly divided into 3 groups: one group practiced rhythmic exercises in combination with basketball training (R-BT, n = 12), another group practiced basketball only (BT, n = 11), and a control group (CON, n = 11). The subjects underwent assessments that included regular and irregular rhythmic exercises, flexibility, coordination, and static balance. After the intervention, all groups showed improvements in their motor skills (MS) when they followed a regular rhythm. The R-BT group showed significantly higher performance in hopping and jumping from preintervention to postintervention [p = 0.003, effect size (ES) = 0.67 and p = 0.005, ES = 0.64, respectively] and differed significantly from the other 2 groups (p < 0.01). In addition, the R-BT group showed a greater improvement in the implementation of irregular rhythms (p < 0.001) and differed significantly from the other groups in all parameters (p < 0.01). The Stork Stand Balance Test improved in the R-BT group and outperformed the other 2 groups, whereas the Alternate-Hand Wall-Toss Test improved in both the R-BT and the BT groups compared with the control group, indicating better coordination. In summary, basketball training preceded by a regular rhythm can lead to greater improvement in MS, resulting in improved coordination and leg stability. These results could be considered crucial for young school-age children who play basketball.
Marisol Castillo Leyva, Claudia G. Benítez Cardoza, Adriana Ganem Rondero
La tricomoniasis, causada por el parásito protozoario Trichomonas vaginalis, es la infección de transmisión sexual (ITS) de origen no viral de mayor incidencia y prevalencia a nivel mundial (1). La tricomoniasis no es una enfermedad mortal, pero tiene serias consecuencias, afectando la salud reproductiva de quien la padece, ya que disminuye la fertilidad, provoca partos prematuros y bajo peso al nacer; también puede provocar discapacidad intelectual en los bebés nacidos de madres contagiadas. También se ha reportado que favorece el contagio de otras ITS, como la de los virus del Sida y del papiloma humano, y predispone al cáncer cervicouterino y de próstata (2,3). El tratamiento contra la tricomoniasis, actualmente y desde hace más de cinco décadas, consiste en el suministro de nitroimidazoles, generalmente metronidazol y tinidazol (todos con el mismo mecanismo de acción). Se ha detectado en la práctica clínica que muchos pacientes que reciben estos fármacos no presentan mejoría y, hasta la fecha, no hay alternativas terapéuticas. La resistencia de los parásitos a los medicamentos usados hasta el momento va en aumento (1). Además de la ineficacia terapéutica, los derivados del nitroimidazol generan diversos efectos secundarios adversos y se ha demostrado que tienen un alto potencial carcinogénico. Esto pone de manifiesto la necesidad de contar con nuevos fármacos contra esta ITS (2,3). En la búsqueda de nuevos fármacos anti-tricomonas, nuestro grupo de trabajo previamente identificó dos compuestos con alto potencial, denominados A4 y D4 (4), con los cuales se está trabajando en la formulación de nanopartículas poliméricas cargadas con estos compuestos que serán integradas en un hidrogel termorreversible de administración vaginal. Se busca que esta opción terapéutica de aplicación tópica disminuya los efectos sistémicos no deseados, presente una eficacia del tratamiento a nivel local en pacientes femeninas, asegure la concentración del fármaco requerida en el sitio de acción y con todo ello se pueda proponer una alternativa a los fármacos convencionales contra la tricomoniasis.
Lawrence David Cerfoglio Machuca, Lídice de Jesús Gómez Cáceres, Jazmín Estela Argüello Benítez
et al.
Objetivo: Estimar la calidad bacteriológica de una muestra de agua para consumo de ESSAP a través de la identificación de: Aerobios mesófilos, coliformes totales, coliformes fecales, E. coli, Pseudomonas aeruginosa en muestras tomadas en Villarrica durante el mes de abril de 2024. Materiales y Método: fué un estudio observacional y transversal. Se recolectó 1000 ml de agua. Se utilizaron 9 muestras simples en 9 frascos estériles y se transportaron en forma refrigerada hasta el laboratorio. Se evalúo recuento de Aerobios mesófilos: (Método Filtración. Con. Inc: 72 h a 35 +/- 1°C). Coliformes totales: (APHA) (Método Filtración. Cond. Inc: 18 – 24 hs a 36 +/- 1°C). Coliformes fecales: (APHA). (Método Filtración. Cond. Inc: 18 – 24 h a 36 +/- 1°C). E. coli: (APHA). (Método Filtración. Cond. Inc: 18 – 24 hs a 36 +/- 1°C). Pseudomonas Aeruginosa: (Método Filtración. Cond. Inc: 40 – 48 h 36 +/- 1°C). Resultados: Se observó que han sido analizados los Aerobios mesófilos con resultados de 0 UFC/ml, asi tambien para los Coliformes totales, los Coliformes fecales, Escherichia coli y Pseudomonas aeruginosa. Conclusion: En la muestra analizada correspondiente al agua para consumo de ESSAP de la ciudad de Villarrica se ha podido estimar con respecto a la calidad bacteriológica de la misma que la presencia de Aerobios mesófilos corresponde al 0 UFC/ml, los Coliformes totales corresponden al 0 UFC/100ml, los Coliformes fecales corresponden al 0 UFC/100ml, Escherichia coli corresponde al 0 UFC/100ml y Pseudomonas aeruginosa corresponde al 0 UFC/100ml.
Abstract Yang, Y-R, Chen, C, Pan, C-H, Yen, S-Y, and Cheng, C-F. Effects of half-time re–warm-up with core strength exercises on subsequent agility and power performance in basketball players. J Strength Cond Res 39(1): 62–69, 2025—This study investigated the effects of half-time re–warm-up (RW) comprising core strength exercise (CSE) on basketball players' subsequent power and change of direction (COD) performance. Twelve male collegiate basketball players were recruited to perform 3 conditions––CSE RW on a stable platform (STA) or an unstable platform (USTA) and passive rest (control, CON)––in randomized, counter-balanced order after a modified Loughborough intermittent shuttle test (LIST). The COD and power performance tests were administered before the LIST and after the interventions. Heart rate (HR) was continuously measured during each trial. Results showed significantly lower changes in T-test time in STA compared with CON (p < 0.05). Changes in countermovement jump height in STA were significantly higher than those in CON (p < 0.05). During the isometric midthigh pull test, changes in the maximum rate of force development (RFD) (p < 0.05), RFD in the range of 0–90 milliseconds (p < 0.05), 0–150 milliseconds (p < 0.05), 0–200 milliseconds (p < 0.05), and 0–250 milliseconds (p < 0.05), in STA were significantly higher than those in CON. In addition, RFD in the range of 0–150 milliseconds (p < 0.05) and 0–250 milliseconds (p < 0.05) in USTA was significantly higher than that in CON. The mean HR during USTA was significantly higher than that in STA and CON (p < 0.05). These findings indicated that CSE RW during halftime might prevent power and COD performance decline in the second half of a game, with practical implications for coaches and players.
Abstract McQuilliam, SJ, Clark, DR, Erskine, RM, and Brownlee, TE. The effect of high vs. moderate-intensity resistance training on strength, power and muscle soreness in male academy soccer players. J Strength Cond Res 37(6): 1250–1258, 2023—The aims of this study were to investigate the impact of high-intensity, low-volume (HRT) vs. moderate-intensity, and high-volume resistance training (MRT) vs. soccer training only (control group [CON]) on changes in strength, power, and speed and to compare delayed onset muscle soreness (DOMS) between groups in male academy soccer players (ASP). Twenty-two ASP (age: 18 ± 1 years) were assigned to HRT (n = 8), MRT (n = 7), or CON (n = 7). High-intensity resistance training completed 2 sets of 4 repetitions parallel back squat (PBS) repetitions at 90% 1 repetition maximum (1RM), while MRT performed 3 sets of 8 repetitions PBS repetitions at 80% 1RM, both once a week for 6 weeks in-season, alongside regular soccer training. All groups completed the following pretraining and posttraining assessments: 3RM PBS, bilateral vertical and horizontal countermovement jumps (CMJ), squat jump (SJ), and 30-m sprint. Delayed onset muscle soreness was assessed using a visual analog scale throughout training. High-intensity resistance training and MRT experienced similar increases compared with CON in absolute PBS 3RM (p < 0.001), SJ height (p = 0.001), and CMJ height (p = 0.008) after training. There was a greater increase in PBS 3RM relative to body mass after HRT than MRT and CON (p = 0.001) and horizontal CMJ distance improved in HRT but not in MRT or CON (p = 0.011). There was no change in 10-m, 20-m, or 30-m sprint performance in any group. High-intensity resistance training volume was 58 ± 15% lower than that of MRT (p < 0.001), and DOMS measured throughout training did not differ between groups (p = 0.487). These findings suggest that 1 HRT session a week may be an efficient method for improving strength and power in ASP in-season with minimal DOMS.
Francesco Bettariga, L. Maestroni, Luca Martorelli
et al.
Abstract Bettariga, F, Maestroni, L, Martorelli, L, Turner, A, and Bishop, C. The effects of a 6-week unilateral strength and ballistic jump training program on the force-velocity profiles of sprinting. J Strength Cond Res 37(7): 1390–1396, 2023—The aims of this study were (a) to investigate the effects of a unilateral training program, compared with a control group, on a force-velocity (F-V) profile in soccer players and (b) to explore such effects on linear speed. Twenty-four soccer players, randomly assigned to a 6-week unilateral strength and ballistic jump training (UNI) (n = 12) or a control group (CON) (n = 12), performed 30-meter linear sprint test. Findings showed small-to-moderate improvements (p < 0.05) in linear speed time (g = 0.66–0.81) and in most F-V variables: maximal running velocity (V0) (g = 0.81), maximal power output (Pmax) (g = 0.49), maximal ratio of force (RFmax) (g = 0.55), optimal velocity (Vopt) (g = 0.83), and maximal speed (g = 0.84) from pre- to post-intervention in the UNI group, whereas no meaningful changes were found in the CON group. The between-group comparison indicated small to large significant changes in V0 (g = 0.95), RFmax (g = 0.48), Vopt (g = 0.95), maximal speed (g = 0.98), and linear speed time performance (g = 0.42–1.02), with the exception of the 0–5 meter distance, in favor of the UNI group. Thus, a unilateral strength and ballistic jump training program can be used to improve the F-V profile and linear speed performance of amateur soccer players.
Keisuke Shibata, Taichi Yamaguchi, Kazuki Takizawa
et al.
Abstract Shibata, K, Yamaguchi, T, Takizawa, K, and Nosaka, K. Comparison in repetitions to failure between concentric-only and eccentric-only dumbbell arm curl exercise at four different relative intensities. J Strength Cond Res 37(9): 1754–1760, 2023—The repetitions to failure (RF) were compared between concentric-only (CON) and eccentric-only (ECC) arm curl exercise for different intensities based on CON and ECC 1 repetition maximum (1RM), respectively, with 2 different inter-repetition rests. Sixteen healthy male, university students (19–22 years) participated in 6 sessions. In sessions 1 and 2, CON and ECC 1RM strength were determined. In sessions 3 to 6, CON and ECC dumbbell arm curl exercises were performed until momentary failure at the intensity of either 70, 80, 90 or 95% of CON and ECC 1RM, respectively, with the inter-repetition rest of 3 seconds (R3) for one arm and 6 seconds (R6) for the other arm in a pseudo-randomized order. A significant (p < 0.01) muscle contraction type × intensity interaction effect was evident for both R3 and R6 conditions. RF was greater (p < 0.01) in ECC than in CON at 70% (34.2 ± 13.3 vs 20.9 ± 5.4), 80% (22.0 ± 6.7 vs 11.6 ± 2.7), 90% (10.1 ± 3.1 vs 5.2 ± 1.3), and 95% (6.8 ± 2.1 vs 2.7 ± 0.8) for R3. RF was also greater (p < 0.01) for ECC than for CON at 80% (24.5 ± 8.1 vs 15.6 ± 3.6), 90% (10.8 ± 2.8 vs 7.2 ± 1.8) and 95% (6.7 ± 2.4 vs 3.9 ± 1.5) for R6, with greater (p < 0.05) RF for R6 than R3. Significant (p < 0.01) correlations in RF were evident between CON and ECC for R3 (r = 0.86) and R6 (r = 0.76). Equations to estimate 1RM were derived for CON and ECC at R3 and R6 (e.g., ECC 1RM = Load × 110.0/[110.5-RF] for R3). These results suggest that fatigue is less in ECC than in CON performed at the same relative intensity.
Abstract Bitel, M, Keir, DA, Grossman, K, Barnes, M, Murias, JM, and Belfry, GR. The effects of a 90-km outdoor cycling ride on performance outcomes derived from ramp-incremental and 3-minute all-out tests. J Strength Cond Res 38(3): 540–548, 2024—The purpose of this study was to determine whether laboratory-derived exercise intensity and performance demarcations are altered after prolonged outdoor cycling. Male recreational cyclists (n = 10; RIDE) performed an exhaustive ramp-incremental test (RAMP) and a 3-minute all-out test (3MT) on a cycle ergometer before and after a 90-km cycling ride. RAMP-derived maximal oxygen uptake (V̇O2max), gas exchange threshold (GET), respiratory compensation point (RCP), and associated power output (PO), as well as 3MT-derived critical power (CP) and work performed above CP, were compared before and after ∼3 hours of outdoor cycling. Six active men served as “no-exercise” healthy controls (CON), who, instead, rested for 3 hours between repeated RAMP and 3MT tests. During the 90-km ride, the duration within the moderate-intensity, heavy-intensity, and severe-intensity domains was 59 ± 24%, 40 ± 24%, and 1 ± 1%, respectively. Compared with pre-90 km, post-RAMP exhibited reductions in (a) V̇O2max (4.04 ± 0.48 vs. 3.80 ± 0.38 L·min−1; p = 0.026) and associated PO (392 ± 30 W vs. 357 ± 26 W; p = 0.002); (b) the V̇O2 and PO at RCP (3.49 ± 0.46 vs. 3.34 ± 0.43 L·min−1; p = 0.040 and 312 ± 40 W vs. 292 ± 24 W; p = 0.023); and (c) the PO (214 ± 32 W vs. 198 ± 25 W; p = 0.027), but not the V̇O2 at GET (2.52 ± 0.44 vs. 2.44 ± 0.38 L·min−1; p = 0.388). Pre-90 km vs. post-90 km 3MT variables showed reduced W′ (9.8 ± 3.4 vs. 6.8 ± 2.6 kJ; p = 0.002) and unchanged CP (304 ± 26 W and 297 ± 34 W; p = 0.275). In the CON group, there were no differences in V̇O2max, GET, RCP, W′, CP, or associated power outputs (p > 0.05) pre-to-post 3 hours of rest. The preservation of critical power demonstrates that longer-duration maximal efforts may be sustained after long-duration cycle. However, shorter sprints and higher-intensity efforts eliciting V̇O2max will exhibit decreased PO after 3 hours of a predominantly moderate-intensity cycle.
Keenan B. MacDougall, Zachary J. McClean, B. MacIntosh
et al.
Abstract MacDougall, KB, McClean, ZJ, MacIntosh, BR, Fletcher, JR, and Aboodarda, SJ. Ischemic preconditioning, but not priming exercise, improves exercise performance in trained rock climbers. J Strength Cond Res 37(11): 2149–2157, 2023—To assess the effects of ischemic preconditioning (IPC) and priming exercise on exercise tolerance and performance fatigability in a rock climbing–specific task, 12 rock climbers completed familiarization and baseline tests, and constant-load hangboarding tests (including 7 seconds on and 3 seconds off at an intensity estimated to be sustained for approximately 5 minutes) under 3 conditions: (a) standardized warm-up (CON), (b) IPC, or (c) a priming warm-up (PRIME). Neuromuscular responses were assessed using the interpolated twitch technique, including maximum isometric voluntary contraction (MVC) of the finger flexors and median nerve stimulation, at baseline and after the performance trial. Muscle oxygenation was measured continuously using near-infrared spectroscopy (NIRS) across exercise. Time to task failure (Tlim) for IPC (316.4 ± 83.1 seconds) was significantly greater than CON (263.6 ± 69.2 seconds) (p = 0.028), whereas there was no difference between CON and PRIME (258.9 ± 101.8 seconds). At task failure, there were no differences in MVC, single twitch force, or voluntary activation across conditions; however, recovery of MVC and single twitch force after the performance trial was delayed for IPC and PRIME compared with CON (p < 0.05). Despite differences in Tlim, there were no differences in any of the NIRS variables assessed. Overall, despite exercise tolerance being improved by an average of 20.0% after IPC, there were no differences in neuromuscular responses at task failure, which is in line with the notion of a critical threshold of peripheral fatigue. These results indicate that IPC may be a promising precompetition strategy for rock climbers, although further research is warranted to elucidate its mechanism of action.
Abstract Horgan, BG, Tee, N, West, NP, Drinkwater, EJ, Halson, SL, Colomer, CME, Fonda, CJ, Tatham, J, Chapman, DW, and Haff, GG. Acute performance, daily well-being and hormone responses to water immersion after resistance exercise in junior international and subelite male volleyball athletes. J Strength Cond Res 37(8): 1643–1653, 2023—Athletes use postexercise hydrotherapy strategies to improve recovery and competition performance and to enhance adaptative responses to training. Using a randomized cross-over design, the acute effects of 3 postresistance exercise water immersion strategies on perceived recovery, neuromuscular performance, and hormone concentrations in junior international and subelite male volleyball athletes (n = 18) were investigated. After resistance exercise, subjects randomly completed either 15-minute passive control (CON), contrast water therapy (CWT), cold (CWI), or hot water immersion (HWI) interventions. A treatment effect occurred after HWI; reducing perceptions of fatigue (HWI > CWT: p = 0.05, g = 0.43); improved sleep quality, compared with CON (p CWT: p = 0.038, g = 0.24). There were trivial to small (p 0.05) observed between the water immersion intervention strategies and CON in performance (p = 0.153–0.99), hormone (p = 0.207–0.938), nor perceptual (p = 0.368–0.955) measures. To optimize recovery and performance responses, e.g., during an in-season competition phase, postresistance exercise HWI may assist with providing small-to-large improvements for up to 38 hours in perceived recovery (i.e., increased sleep quality and reduced fatigue) and increases in circulating testosterone concentration. Practitioners should consider individual athlete neuromuscular performance responses when prescribing postexercise hydrotherapy. These findings apply to athletes who aim to improve their recovery status, where postresistance exercise HWI optimizes sleep quality and next-day perceptions of fatigue.
Pablo Pérez-Ifrán, Carlos A Magallanes, Flávio A. de S. Castro
et al.
Abstract Pérez-Ifrán, P, Magallanes, CA, de S. Castro, FA, Astorino, TA, and Benítez-Flores, S. Extremely low-volume burpee interval training equivalent to 8 minutes per session improves vertical jump compared with sprint interval training in real-world circumstances. J Strength Cond Res 38(1): 10–20, 2024—The aim of this study was to compare the cardiometabolic and physical effects of 2 time-matched high-intensity programs in a real-world environment. Forty-three active and healthy adults (sex = 31 men and 12 women; age = 27 ± 5 years; peak heart rate [HRpeak] = 190.7 ± 10.6 beat·min−1) were randomized to 2 very low-volume protocols (∼8 minutes): sprint interval training (SIT) (n = 15), burpee interval training (BIT) (n = 15), and control (CON) (n = 13). Subjects in SIT and BIT performed 5 days of 10 × 4 second “all-out” efforts with 30 seconds of recovery. Body composition, blood pressure, countermovement jump (CMJ), 10-m sprint, shuttle run test (SRT), autonomic modulation, self-efficacy, and intention were evaluated before and after training. Sprint interval training elicited a higher %HRpeak, energy expenditure, rating of perceived exertion category ratio 10 scale, and feeling scale than BIT (p 0.05). No changes were observed in body composition, blood pressure, 10-m sprint, SRTV̇O2max, or autonomic variables with training (p > 0.05). Results exhibit that extremely low-volume SIT improved running performance, whereas BIT increased the vertical jump.
Abstract Rauseo, ML, Feairheller, DL, LaRoche, DP, and Cook, SB. Acute effect of dynamic and gluteal resistance exercise warm-up protocols on lower-extremity jump landing mechanics in college-aged females. J Strength Cond Res 38(2): 259–265, 2024—Inadequate neuromuscular control of the femur by the gluteal musculature is associated with noncontact and overuse injuries to the knee. Acute bouts of resistance exercises targeting the gluteal musculature can be prescribed as part of a warm-up protocol with the goal of improving subsequent neuromuscular control and performance. The purpose of this study was to determine the effect that a warm-up protocol including moderate-intensity gluteal resistance exercises (GRE) has on single leg jump landing biomechanics. Seventeen healthy, college-aged, recreationally active females (mean ± SD; age = 21.4 ± 1.9 years; height = 166.9 ± 5.7 cm; body mass = 62.5 ± 7.4 kg) performed 3 single leg hop trials per leg after completing no warm-up (CON), a dynamic warm-up (DWU), and a dynamic warm-up with gluteal resistance exercises (DWU + GRE) across 3 laboratory visits. Lower extremity kinetic and kinematic variables were assessed during single leg hops from the point of initial foot contact to deepest knee flexion. Biomechanical differences between dominant and nondominant limb landings were also assessed. Dominant limb hip internal rotation angle after DWU + GRE (2.03 ± 9.92°) was significantly greater (p ≤ 0.05) compared with CON (−3.36 ± 7.74°). Peak knee adduction moment (56.8%), peak knee flexion angle (5.7%), and peak knee external rotation angle (17.0%) were significantly greater (p ≤ 0.017) in the dominant limb, compared with the nondominant limb, across warm-up protocols. The combined DWU + GRE warm-up protocol did not have a substantial impact on landing biomechanics. Clinicians prescribing GRE before activity should not expect significant changes in movement patterns after a single bout.
En este articulo damos un panorama sobre la clasificación de los embaldosados del plano euclídeo por copias de un único polígono convexo (teselados monoedralesconvexos). Primero mostramos que el teselado con polígonos regulares sólo es posible con triángulos, cuadrados y hexágonos, hecho ya conocido por los antiguos griegos, y que si el polígono es no-convexo entonces hay infinitos teselados posibles. Así, nos enfocamos en teselados convexos con polígonos no-regulares. Primero mostramos que cualquier triangulo o cuadrilátero tesela el plano. Después mostramos que un polígono que tesela el plano debe tener 6 lados o menos. A continuación, nos ocupamos de los hexágonos y mostramos que solo hay 3 familias distintas de hexágonos convexos que teselan el plano. Finalmente consideramos el caso de los pentágonos que es mas delicado, cuya clasificación completa pudo terminarse muy recientemente en 2017. Mostramos que hay solo 15 familias distintas de pentágonos que teselan el plano
Ferley, DD, Scholten, S, and Vukovich, MD. Combined sprint interval, plyometric, and strength training in adolescent soccer players: effects on measures of speed, strength, power, change of direction, and anaerobic capacity. J Strength Cond Res XX(X): 000-000, 2020-During winter, many soccer players train indoors to improve the aerobic and anaerobic demands of their sport. Sprint interval training (SIT) performed on a treadmill using level and graded conditions represents a viable alternative to traditional endurance conditioning. To date, little research exists contrasting the effects of these conditions. Therefore, the purpose of this investigation included examining the effects of 2 approaches combining SIT, plyometrics, and strength training on performance measures in soccer players aged 13-18 years over 8 weeks. Forty-six subjects were divided into 3 groups. Group 1 performed SIT using predominantly inclined treadmill conditions combined with resistance and plyometric training (INC, n = 17). Group 2 performed SIT using level treadmill grades and completed the same resistance and plyometric training (LEV, n = 14). Group 3 was a control group representing various sports who continued their normal training (CON, n = 15). Pre- and posttests assessed speed, strength, change of direction, and anaerobic capacity, including sprint speed (9.1 and 18.3 m sprint), unilateral triple hop for distance (3HOP_L and 3HOP_R), pro agility change of direction (PA); treadmill running to exhaustion on a 20% grade (CFMod), and hip flexor maximum strength (HF_1RM). After training, INC and LEV improved more in all measures compared with CON. Furthermore, INC improved significantly more compared with LEV in 9.1- and 18.3-m sprint, 3HOP_L and 3HOP_R, PA, CFMod, and HF_1RM (p < 0.05). We conclude that strength and plyometric training combined with incline-based SIT is more effective than a similar training approach using level-grade SIT.