Lower Body Muscular Power Research Articles

Lower-body muscular power predicts performance on urban combat simulation.

Military operations in urban environments requires faster movements and therefore may place greater demands on soldier strength and anaerobic ability. The aim was to study how physical fitness and body composition are associated with occupational test for urban combat soldiers before and after a 5-day military field exercise (MFE). Twenty-six conscripts (age = 20±1 yrs.) volunteered, of which thirteen completed the study. Occupational performance was determined by using the newly developed Urban Combat Simulation test (UCS); which included 50-m sprinting, moving a truck tire (56 kg) 2 meters with a sledgehammer, a 12-m kettlebell carry (2×20 kg) up the stairs with a 3-m ascent, 4-time sandbag lifts (20 kg) with obstacle crossing, and a 20-m mannequin (85 kg) drag. Aerobic and muscle fitness, as well as anaerobic capacity were measured, and, body composition was assessed with multifrequency bioimpedance analysis. The UCS performance correlated significantly with standing long jump performance, as well as lower and upper body maximal strength before (r = -0.56 to -0.66) and after (r = -0.59 to -0.68) MFE, and, with body mass and FFM before (r = -0.81 to -0.83) and after (r = -0.86 to -0.91) MFE. In the regression analyses, fat free mass (R2 = 0.50, p = 0.01) and counter movement jump in combat load (R2 = 0.46, p = 0.009) most strongly explained the UCS performance. This study demonstrated that muscle mass and lower body explosive force production together with maximal strength are key fitness components related to typical urban combat soldiers' military tasks. Physical training developing these components are recommended.

Determining the optimal duration of plyometric training for enhancing vertical jump performance: a systematic review and meta-analysis

Introduction. Plyometric training is done in many ways, but countermovement jumps and squat jumps are easy and safe methods involving minimal use of equipment to increase lower body muscular power. There is enough evidence in the literature to support the notion that plyometric training increases vertical jump height. But the combination of countermovement jumps and squat jumps and its impact on vertical jump height is still unclear.
 Purpose. Therefore, to examine the importance of various plyometric training techniques, this meta-analytical evaluation was created. 
 Materials and Methods: PubMed, MEDLINE, and Google Scholar databases were searched through August 2022. Empirical studies are expressed in the English language and issued within the last twenty-eight years. Included squat jump and countermovement jump interventions for improving vertical jump height. The studies used a training duration of a minimum of four weeks or above involving a control group included. As an approach to plyometric training that raises vertical jump height, the effects of countermovement jump and squat jump training were evaluated. To assess the level of heterogeneity, the I2 statistics were utilized. The value of I2 above 75% indicates significant heterogeneity and leads to the subgroup analysis method. Summary effects were calculated using standardized mean difference. With the help of the Cochrane tool, the risk of bias was assessed.
 Results: The 22 study results all met the enclosure criteria. The meta-analysis indicated that the total impact of squat jumps training had high effects on vertical jump height [Effect Size = 0.96, (95% CI,0.57 to 1.35)]. A moderate degree [Effect Size = 0.91, (95 % CI,0.46 to 1.37)] of effects of countermovement jumps training on vertical jump height was reported by included interventions. Lesser than 10 weeks of plyometric training intervention duration they probably had a small effect on countermovement jumps [Effect Size = 0.79, (95 % CI, 0.30 to 1.29)].
 Conclusion: Squat jumps and countermovement jumps are an efficient kind of training to increase the vertical jump height of male and female athletes, according to our study on plyometric training. Higher posttests mean differences were found in the studies including male subjects. The length of intervention has proportional effects on vertical jump height the recommended length of training should lie between 8 to 12 weeks. The effect size ranged between small to large degrees was observed in overall and subgroup analysis.

Load and muscle group size influence the ergogenic effect of acute caffeine intake in muscular strength, power and endurance.

Although acute caffeine intake seems to improve muscular strength-power-endurance performance, there is scarce evidence evaluating upper vs lower-body exercises at different loads. Thus, this study aimed to examine the effects of acute caffeine intake on upper and lower-body muscular strength, power and endurance performance at different loads. Twenty resistance-trained athletes (male/female: 10/10; age: 23 ± 4years; body mass: 70.6 ± 15.1) participated in a double-blind, placebo-controlled, cross-over and randomized study. Participants were provided with either 3mg/kg of body mass of caffeine or maltodextrin (placebo). Sixty minutes after ingestion, they performed muscular strength and power assessment for bench press and back squat exercise at 25%, 50%, 75% and 90% 1-repetition-maximum (1RM), performing 3, 2, 1 and 1 repetitions respectively, followed by muscular endurance assessment for both exercises at 65% and 85% 1RM performing until task failure. Isometric handgrip, isometric mid-thigh pull and vertical jump tests were also performed. In muscular strength and power, compared to placebo, caffeine improved mean velocity (P = 0.045; pη2 = 0.101), mean power (P = 0.049; pη2 = 0.189) and rate of force development (RFD, P = 0.032; pη2 = 0.216), particularly in back squat exercise at 75% and 90% 1RM where mean velocity increased by 5-7% (P = 0.48-0.038; g = 0.348-1.413), mean power by 6-8% (P = 0.050-0.032; g = 0.547-0.818) and RFD by 17-97% (P = 0.042-0.046; g = 1.436-1.196). No differences were found in bench press exercise. In muscular endurance, caffeine improved the number of repetitions in all exercises and loads (P = 0.003; pη2 = 0.206), but only in back squat exercise at 85% 1RM, caffeine increased mean and peak velocity (8-9%, P = 0.006-0.004; g = 2.029-2.075), mean and peak power (10-13%, P = 0.006-0.003; g = 0.888-1.151) and force peak (3%, P = 0.009; g = 0.247). Acute caffeine intake (3mg/kg) improved muscular strength, power and endurance performance, revealing a more pronounced effect at high-loads (≥ 75% 1RM) and in lower-body (back squat) than in upper-body exercise (bench press) according to muscle group size.

The Acute Impacts of Resistance Training Performed with and without Blood Flow Restriction on Lower Body Muscular Power

The Acute Impacts of Resistance Training Performed with and without Blood Flow Restriction on Lower Body Muscular Power

ASSOCIATION BETWEEN SPORT RELATED POLYGENIC PROFILE AND MAGNITUDE OF PHYSICAL PERFORMANCES CHANGES FOLLOWING RESISTANCE TRAINING AMONG NOVICE FIELD HOCKEY ATHLETES

Background: Studies have shown that inter-individual variation in response to resistance training is attributed to genetic variation. Aim: To correlate total genotype scores (TGS) with the magnitude of physical performances (skeletal muscle mass, muscular strength, muscular power, performance decrement, and VO2max) change, following 8 weeks of resistance training. Methods: We included forty-five (N=45) participants (age = 16.53 ± .5 years old, body mass = 61.03 ± 6.67 kg, height = 1.67±.05 m) and randomly assigned into; high intensity resistance training (n=15), moderate intensity resistance training (n=15) and a control group (n=15). They were prescribed with the same upper and lower body exercise routines. Pre- and post-test physical performances were measured. Genotyping was conducted using in-house designed allele-specific polymerase chain reaction assays. TGS for nine SNPs: Angiotensin Converting Enzyme, ACE rs1799752; Alpha-acitin-3, ACTN3 rs1815739; Adrenergic Receptor B3, ADRB3 rs4994; Angiotensinogen, AGT rs699; Bradykinin Receptor B2, BDKRB2 rs1799722; Peroxisome Proliferator-Activated Receptor Alpha, PPARA rs4253778; Peroxisome Proliferator-Activated Receptor Gamma Co-Activator 1-Alpha, PPARGC1A rs8192678; Thyrotropin Releasing Hormone Receptor, TRHR rs7832552 and Vascular Endothelial Growth Factor, VEGF rs1870377,were calculated and assigned with strength-power and endurance quality. Pearson correlation analysis was employed to investigate the correlation between TGS, and magnitude of physical performances change following intervention. Result: There is a significant correlation between strength-power TGS with lower body muscular strength (r= .65, p<.01) and power (r= -.69, p<.01) following moderate intensity resistance training. Conclusion: In this study, it is demonstrated that participants with higher strength-power TGS, gained greater lower body strength improvement and lesser muscular power decrement even with moderate intensity as compared to high intensity resistance training. Therefore, personalising training based on athlete’s genetic profile may optimise performance.

Effects of the Off-Season on Muscular Power in Professional Rugby League.

Periods away from training and competition are necessary for physical and mental restoration in sport. There is limited research investigating changes to physical qualities in rugby league following prolonged breaks. This study aimed to evaluate the effects of the off-season on muscular power in rugby league. In addition, this study aimed to determine whether the type and volume of training players chose to complete had any relationship to feelings of restoration and/or readiness to return to training. Twenty professional rugby league players participated in this study. Lower-body muscular power was evaluated using a countermovement jump prior to the off-season and at the recommencement of training. Players completed a questionnaire to identify training and activities completed during the break and to assess feelings of restoration and readiness to commence training. Linear regression was used to estimate the effects of the number of days off on muscular power. One-way repeated-measures analysis of variance was conducted to examine differences in lower-body power throughout the study. Spearman rank order correlation was calculated to determine the relationship between off-season activities and feelings of restoration and readiness. Peak velocity and peak force significantly increased following the off-season break. There were significant relationships between mental restoration and upper-body resistance training, as well as physical restoration and full-body resistance training. The off-season has a positive effect on a player's ability to generate muscular power. Coaches may want to encourage players to complete resistance training sessions with the aim simply to maintain training load and potentially help players to feel rested.

Anthropometric Parameters, Physical Activity, Physical Fitness, and Executive Functions among Primary School Children.

Physical activity during childhood and adolescence favors brain development and cognitive functioning, particularly the executive functions. This study aimed to assess potential associations between anthropometric parameters, physical activity, physical fitness, and executive functions among elementary school children returning to school after the COVID-19 lockdown in Chile. School-age male and female participants (n = 90; age, 10–12 years) participated in the study. To determine the association between variables, a multivariable linear regression analysis was performed. Higher fat-related anthropometric indexes were associated with lower working memory, cognitive flexibility, planning, and attention (r = −0.55 to −0.22; p = 0.031 to <0.001). In contrast, higher physical activity levels, better sprint performance, higher lower-body muscular power, and greater upper-body muscular strength were associated with better working memory, cognitive flexibility, inhibition, planning, and/or attention (r = 0.19 to −0.54; p = 0.04 to <0.001). Current results consistently suggest the need for adequate levels of physical activity, physical fitness, and anthropometric parameters among the school-age population to promote healthy and adequate executive functions.

Lower-body muscular power and exercise tolerance predict susceptibility to enemy fire during a tactical combat movement simulation

This study examined if field-expedient physical fitness/performance assessments predicted performance during a simulated direct-fire engagement. Healthy subjects (n = 33, age = 25.7 ± 7.0 years) completed upper- and lower-body strength and power assessments and a 3-min all-out running test to determine critical velocity. Subjects completed a simulated direct-fire engagement that consisted of marksmanship with cognitive workload assessment and a fire-and-move drill (16 × 6-m sprints) while wearing a combat load. Susceptibility to enemy fire was modelled on average sprint duration during the fire-and-move drill. Stepwise linear regression identified predictors for the performance during the simulated direct-fire engagement. Critical velocity (β = −0.30, p < 0.01) and standing broad jump (β = −0.67, p < 0.001) predicted susceptibility to enemy fire (R 2 = 0.74, p < 0.001). All predictors demonstrated poor relationships with marksmanship accuracy and cognitive performance. These data demonstrate the importance of exercise tolerance and lower-body power during simulated direct-fire engagements and provide potential targets for interventions to monitor and enhance performance and support soldier survivability. Practitioner Summary: This study identified field-expedient physical fitness/performance predictors of a simulated direct-fire engagement which evaluated susceptibility to enemy fire, marksmanship, and cognitive performance. Our findings suggest that high-intensity exercise tolerance and lower-body power are key determinants of performance that predicted susceptibility to enemy fire.

The Effects of an Eight Week Plyometric-based Program on Motor Performance Skills and Muscular Power in 7–8-Year-Old Primary School Students

Background of Study: Competence in motor performance skills is important in enabling children to be physically literate. Plyometric-based training has been suggested as an effective means to enhance motor performance skills in young athletes. However, no studies have reported the effects of a whole body plyometric-based program integrated into physical education on motor performance skills with young children. Objective: This study aims to examine the effect of a plyometric-based program on primary school students’ motor performance skills, upper and lower body muscular power, and reactive strength index. Method: The sample was composed of 61 primary school students, 29 girls and 32 boys, aged 7–8 years old, from two second-grade Physical Education (PE) classes. Both groups participated in their regular eight-week PE lessons (50-minute classes twice a week). During the study, the plyometric group performed a plyometric-based program in the 15-minute warmup of each class, while the comparison group performed regular warmup activities. Student’s motor performance skill proficiency, reactive strength index, lower and upper body muscular power were assessed before and after the eight weeks of PE lessons. The data were analysed using a two-way analysis of variance, followed by pairwise comparisons with the Bonferroni adjustment. Results: The data analysis indicated significant increases in motor performance skill proficiency, upper and lower body muscular power in the plyometric group vs comparison group (p ≤ 0.05). Conclusion: These results suggest that including a plyometric-based program in the PE warmup phase of the lessons may improve motor performance skills and muscular power in primary school students.

EFFECT OF HIGH AND LOW FLEXIBILITY ON AGILITY, ACCELERATION SPEED AND VERTICAL JUMP PERFORMANCE OF VOLLEYBALL PLAYERS

This study aimed to assess the effect of high and low levels of flexibility on key performance indicators of volleyball performance. Eighty-four volleyball players (n=84; mean±SD; decimal age: 16.57±1.51; height (cm): 176.23±8.77; body mass (kg): 66.14±11.79) were selected for the study. The design of the study was cross-sectional and to measure selected variables i.e. agility, lower body muscular power, and acceleration speed; 6×10 m shuttle run, countermovement jump (with arm swing) test and 20 m sprint test (standing start) were used. To measure the flexibility level of the players, sit and reach test was used. Shapiro-Wilk normality test was conducted to check the distribution of data and the Levine test was applied to check homogeneity of the variance in data. Participants were divided into two groups i.e. High Flexibility Group (HFG) and Low Flexibility Group (LFG) using k-means cluster analysis and independent t-test was applied to find the differences between HFG and LFG. The level of significance was set at p &lt; 0.05. Results showed statistically significant difference between HFG and LFG in agility, acceleration speed and lower body muscular power and, based on the results, it was concluded coaches should include flexibility training in the regular training programme. The results obtained supported the rationale that baseline flexibility may influence the performance of volleyball players.&#x0D; &#x0D; &lt;p&gt; &lt;/p&gt;&lt;p&gt;&lt;strong&gt; Article visualizations:&lt;/strong&gt;&lt;/p&gt;&lt;p&gt;&lt;img src="/-counters-/edu_01/0778/a.php" alt="Hit counter" /&gt;&lt;/p&gt;

Anthropometric and fitness normative values for young karatekas.

To provide information regarding the anthropometric and fitness profile of young karatekas and to study its evolution with age. Data from top-level karatekas were included in the analysis: 97 athletes in the U14 category (12–13 years old), 238 in cadet (14–15 years old), 261 in junior (16–17 years old) and 177 in U21 (18–20 years old), which makes a total of 773 athlete data sets. Karatekas underwent anthropometric (weight, height, body mass index and body fat percentage) and fitness (sit and reach, 20-m shuttle run, standing long jump, overhead 3-kg ball throw, 10x5-m shuttle run, and plate-tapping) assessments during the training camps organized by the Spanish National Karate Federation between 1999 and 2016. Male karatekas were taller and heavier, and performed better than females in all the fitness dimensions assessed, except for flexibility and speed of upper limb movements. The obtained cardiovascular and lower-body muscular values indicated that karatekas in this study were placed between the 80th and the 90th percentile when compared with the general population. The results of the agility, coordination and speed of upper limb movements, and flexibility tests showed that the karatekas obtained much higher scores than those observed in age-matched populations. Young karatekas show a high fitness level in comparison with the general population, especially with regards to aerobic performance, lower-body muscular power and upper-limb movement speed. Reference values of anthropometric and fitness dimensions are provided in order to be used by coaches, conditioning trainers and sport scientists when testing young male and female karatekas.

Relationship between Firefighter Physical Fitness and Special Ability Performance: Predictive Research Based on Machine Learning Algorithms.

Firefighters require a high level of physical fitness to meet the demands of their job. The correlations and contributions of individual physical health parameters to the tasks of firefighting would enable firefighters to focus on the effects of specific physical conditions during their physical training programs. Therefore, the purpose of the present study was to identify the relationships between various physical health parameters (weight, maximum oxygen uptake, body fat percentage, upper body muscular power and lower body muscular power) and performance on simulated firefighting ability tasks, which included a set of seven tasks (rope climb, run 200 m round trip with load, 60 m carrying a ladder, climb stairs with load, evacuation of 400 m with supplies, run 5 km with an air respirator, run 100 m with the water hose). Through use of a partial least-squares regression (PLSR) algorithm to analyze the linear correlation, we revealed the change in various training performances of specific ability tests with physical fitness parameters. The present study demonstrated significant relationships among physical health parameters and performance on simulated firefighting ability tasks, which also represent that those parameters contributed significantly to the model’s predictive power and were suitable predictors of the simulated firefighting tasks score.

A 47-Year Comparison of Lower Body Muscular Power in Spanish Boys: A Short Report.

Much of the evidence examining temporal trends in fitness among youth has found a decrease in measures of muscular strength and muscular power over recent decades. The aim of this study was to examine trends in lower body muscular power in Spanish boys over 47 years. In 1969 140 boys (10–11 years; body mass index = 19.24, SD = 2.91 kg/m2) and in 2016, 113 boys (10–11 years; body mass index = 19.20, SD = 3.15 kg/m2) were recruited. Lower body power was assessed using the vertical jump (VJ) and standing long jump (SLJ) tests. Significant differences and a large effect size were shown between groups in the SLJ (p = 0.001; d = 0.94) and the VJ (p = 0.001; d = 0.66). SLJ data in 1969 were higher (1.52 m, SD = 0.19) when compared to the 2016 data (1.34 m, SD = 0.18). The VJ performance of the 1969 sample was also higher (25.95 cm; SD = 6.58) than the 2016 sample (21.56 cm; SD = 4.72). SLJ and VJ performance of the 2016 group decreased 11.8% and 16.9%, respectively. There were no significant differences between groups in body mass index. The results indicate a secular decline in lower body muscular power in 10–11-year-old Spanish boys with no significant changes in body mass index over the 47-year study period.

Effects Of Unilateral Resistance Training On Muscular Strength, Power, And Measures Of Core Stability In Trained Individuals

PURPOSE: This study examined the effects of unilateral resistance training on lower body muscular strength and power, and measures of core stability in resistance-trained college students. METHODS: Participants (N=22) underwent either 10 sessions of lower body unilateral (URT) or bilateral (BRT) resistance training on three non-consecutive days per week for three weeks. Training sessions consisted of three sets of five repetitions at 80% 1-RM for each exercise. BRT exercises included the barbell back squat, deadlift, and weighted jump squat. URT exercises included the Bulgarian split squat, single leg of Romanian deadlift, and single leg weighted jump squat. Outcome measures were a one repetition maximum (1-RM) leg press for lower body strength, standing vertical jump (VJ) for lower body power, and double leg lowering (DLL), hip abduction isometric strength (HAIS), and Sorensen (SOR) tests for core stability. RESULTS: Training elicited a positive main effect of time for all variables (p < 0.05). Both groups improved pre to post training in 1-RM (297±95.4 to 373±114 kg), VJ (56.5±15.0 to 62.2±10.8 cm), DLL (33.9±14.9 to 43.6±13.2 deg), HAIS (29.6±8.86 to 32.6±10.1 kg), and SOR (91.4±33.1 to 112±36.7 sec). The magnitude of change was similar between groups for all variables except HAIS, in which the UL group demonstrated significantly (p=0.0155) greater improvement (14.3% vs. 5.3%). However, the effect size was larger in UL for all variables except VJ (Cohen’s d = 0.86 vs. 0.61 for 1-RM, 0.92 vs. 0.55 for DLL, 0.64 vs. 0.19 for HAIS, 0.90 vs. 0.36 for SOR). CONCLUSIONS: Relative to bilateral training, unilateral resistance training produced similar improvements in measures of lower body strength and power in trained subjects. Additionally, these data suggest that unilateral training may potentially offer the benefit of enhanced core stability.

Retrospective Cohort Analysis of the Army Physical Fitness Test and the Occupational Physical Assessment Test in Reserve Officer Training Corps Cadets: A Brief Report.

Because of the physical fitness requirements of Military Occupational Specialties (MOSs) within the US Army, fitness testing batteries have been developed. The Occupational Physical Assessment Test (OPAT) has been used for determining occupation assignment and is meant to assess upper and lower body muscular power, muscular strength, and aerobic capacity. The Army Physical Fitness Test (APFT) is a general fitness assessment meant to test upper and lower body muscular endurance and aerobic capacity. Comparisons of the two testing batteries as well as evaluation of potential sex differences are missing from current literature. Therefore, the purpose of this study was to investigate the sex differences in APFT and OPAT performances, as well as the relationship between the APFT and OPAT individual test events. A retrospective analysis, approved by the university's institutional review board, was conducted on a sample of 90 Reserve Officer Training Corps (ROTC) cadets (men, n=72, age=19.7±2.2years, height=1.79±0.21m, mass=75.18±12.38kg; women, n=18, age=19.8±2.2years, height=1.63±0.09m, mass=65.56±9.03kg) from the Fall 2018 semester. The cadets completed the APFT (maximal push-ups, maximal sit-ups, 2-mile run) and OPAT (standing long jump, seated power throw, a deadlift test, and interval aerobic run) protocols per army standards. Analysis of variance assessed sex differences and correlation coefficients were computed to examine the strength of relationships between individual test events (p<0.05). All APFT and OPAT event performances were lower in women compared to men (p<0.05), except the sit-up test (p=0.382). Seated power throw (Z=2.285; p=0.011), 2-mile run (Z=1.97; p=0.024), and strength deadlift (Z=1.783; p=0.037) were more highly correlated to push-up than aerobic interval run. The standing long jump (Z=1.741; p=0.041), power throw (Z=3.168; p=0.001), strength deadlift (Z=2.989; p=0.001), and shuttle run (Z=2.933 p=0.002) were less correlated with the sit-up than 2-mile run. The interval aerobic run was more related to the 2-mile run than the power throw (Z=1.809, p=0.035). Compared to the aerobic interval run, the standing long jump (Z=2.969, p=0.001) and strength deadlift (Z=4.237, p<0.001) were more related to the seated power throw. Sex differences and varied relationships among individual events on two common military fitness test batteries were observed. Lower performances on APFT and OPAT by women may suggest the need to evaluate potential training methods to assist women in reaching their desired MOS. Further, individual OPAT events displayed weaker relationships compared with the relationships among individual APFT event, suggesting a greater degree of redundancy among the events on the APFT. Therefore, the combination of APFT and OPAT may offer a greater opportunity to measure physical fitness capabilities as related to various military job performance tasks.

Relationships Between Punch Impact Force and Upper- and Lower-Body Muscular Strength and Power in Highly Trained Amateur Boxers.

Dunn, EC, Humberstone, CE, Franchini, E, Iredale, KF, and Blazevich, AJ. Relationships between punch impact force and upper- and lower-body muscular strength and power in highly trained amateur boxers. J Strength Cond Res 36(4): 1019-1025, 2022-This study examined the relationship between upper- and lower-body strength and power characteristics and punch performance in 28 highly trained male amateur boxers. Punch performance was assessed with a custom-built punch integrator using a 3-minute maximal effort punch test that contained straight- and bent-arm punches from the lead and rear hands. Peak punch force and force-time variables including impulse and rate of force development (RFD; calculated to various points) were assessed. Force, power, and RFD of the upper and lower body were assessed with countermovement bench throw, isometric bench push, countermovement jump (CMJ), and isometric midthigh pull (IMTP) tests. Correlation and regression analyses revealed significant (p < 0.05) relationships between peak punch force and forces measured in CMJ and IMTP tests. In addition, peak punch force was moderately and significantly correlated to body mass, but RFD in the lower body was not. Moreover, no meaningful relationships between punch performance characteristics and any upper-body strength or power parameter were identified. The results of this study show that lower-body strength but not RFD had a moderate to strong positive and significant correlation to peak punch force production. Although upper-body strength and power are expected to be important in boxing, they did not discriminate between boxers who punched with higher or lower peak force nor were they correlated to peak punch force. Training that improves lower-body strength without increasing total body mass (to maintain weight category) may positively influence punch capacity in highly trained amateur boxers.

The Importance of Lower Body Strength and Power for Future Success in Professional Men’s Basketball

Heavy resistance exercise is often prescribed for collegiate basketball players to enhance game performance, but few data are available concerning the transference of lower body strength and power to the opportunity to play professionally after college. This study investigated if lower body muscular power and strength measures obtained during the barbell squat are related to future professional playing opportunities. The data was collected over a seven year period from a collegiate men’s basketball program (n=37; X±SD, age=20.0±1.4 yrs, hgt=1.98±0.09 m, bw=94.5±11.8 kg). Lower body strength was determined from 1 repetition maximum (1RM) tests of the parallel high-bar squat. Maximum lower body squat power was determined from speed squat testing across a load spectrum (30-90% 1RM) while an external tethered dynamometer or a 3-D video motion capture system quantified barbell power. Repeated measures ANOVA with Tukey’s HSD post hoc, Spearman ρ correlations, and Cohen’s D effect sizes were used to analyze the results. Subjects who subsequently played in the NBA or in professional leagues elsewhere had greater lower body strength and power. This was mainly attributed to their greater body mass, since strength and power relative to body mass was not different between the groups. Even without statistically significant differences, effect sizes consistently indicated moderate to large differences between the NBA and other professional groups when compared to those who did not play professionally. Regardless, lower body strength and power were related to post-collegiate playing opportunities, with greater values related to higher levels of professional play.

Small-Sided Games are More Enjoyable Than High-Intensity Interval Training of Similar Exercise Intensity in Soccer.

IntroductionHigh-intensity interval training (HIIT) and small-sided games (SSG) have been applied and tested for athletes in order to enhance the soccer performance. For this reason, this experimental study aimed to compare the effects of SSGs and HIIT on power, physiological responses and perceived enjoyment.Materials and MethodsSixteen youth soccer players (age, 17.5±0.6 years, mean±standard deviation; height, 178.2±6.4 cm; body mass, 70.4±5.4 kg; body fat, 10.6±0.8%) completed one session each of HIIT and SSG on separate days with 1 week between sessions. Each session lasted 25 mins (4x4 mins work with 3 mins of passive recovery in-between). SSGs consisted of 4 versus 4 player games on a 25×35 m pitch, and HIIT consisted of intermittent 15-s runs at 110% maximal aerobic speed separated by 15 s of passive recovery. Psychological responses following each protocol were assessed using the Physical Activity Enjoyment Scale (PACES). Heart rate (HR) was continuously recorded, rating of perceived exertion (RPE) and lactate concentration [La] were measured after each training session. Lower body muscular power was assessed using the 5-jump test relative to leg length (5JT-relative) before and after each training session, where greater average distance per stride over five sequential jumping strides indicated greater muscular power.ResultsHIIT and SSG showed no significant difference in HR, RPE and [La] responses (p=0.70, ES=0.11; p=0.61, ES=0.08 and p=0.38, ES=0.21, respectively). 5JT-relative decreased significantly for SSG and HIIT (p<0.05, ES=0.50 and p<0.05, ES=0.40, respectively). PACES score was greater in SSG compared to HIIT (ES=5.35, p<0.001).ConclusionHIIT and SSG sessions induced similar physiological responses; however, SSGs induced a higher enjoyment level than HIIT. Coaches could choose between these training modalities according to the objective of their training session, considering the enjoyment-related advantages of SSGs.

Physiological Responses of a Jaw-Repositioning Custom-Made Mouthguard on Airway and Their Effects on Athletic Performance.

Martins, RS, Girouard, P, Elliott, E, and Mekary, S. Physiological responses of a jaw repositioning custom-made mouthguard on airway and their effects on athletic performance. J Strength Cond Res 34(2): 422-429, 2020-Advanced dental techniques such as jaw-repositioning have shown to increase lower body muscular power such as vertical jump, but its effects on acceleration and speed have not been studied. Similarly, jaw repositioning is commonly used to increase airways volume and ventilation in a special population (i.e., obstructive sleep apnea); however, its ergogenic effects on aerobic performance have yet not been studied. The purpose of the cross-over study was to investigate the effects of a jaw-repositioning custom-made mouthguard (JCM) on volumetric changes in airway and jaw position and determine the effects this may have on aerobic and anaerobic performance. Results indicated that jaw-repositioning custom-made mouthguard may have an ergogenic effect on performance. The JCM condition showed an increase of 13% in upper airway volume (p = 0.04), 10% in upper airway width (p = 0.004), 7% in ventilation (p = 0.006), 5% in maximal aerobic power (p = 0.003), 4% in time to exhaustion (p = 0.03), 3% in vertical jump (p = 0.03), 2% in broad jump (p = 0.009), and a decrease of 4% in 20-m (p = 0.04) and 2% in 40-m (p = 0.001) sprint times. This is the first study to demonstrate a significant link between jaw repositioning, airway volumetric change, and performance enhancement in both aerobic and anaerobic performances. The results of this study may lead to a change in culture for the use of mouthguards in different sports applications, from high orofacial injury risk sports to other sports, specifically for ergogenic enhancement.

Physical Determinants of Golf Swing Performance: A Review.

Sheehan, WB, Bower, RG, and Watsford, ML. Physical determinants of golf swing performance: A review. J Strength Cond Res 36(1): 289-297, 2022-Traditionally, golf practice has primarily focused on the mental, technical, and skill aspects as the primary means to improve performance. Only recently has a greater emphasis been placed on the physical components with balance, muscular strength, power, and specific muscle-tendon properties demonstrating positive associations with club head speed and carry distance. Accordingly, this review will explore the influence of these physical components on measures of golf swing performance. Superior balance may allow players to effectively deal with the need to shift weight during the swing as well as different stance positions, whereas superior lower-body muscular strength, power, and stiffness may allow more mechanical work to be performed on the club during the swing per unit of time, consequently increasing club head speed. Alternatively, flexibility may also contribute to enhanced force production with a greater range of motion, particularly when generating the "X-factor," allowing for a longer backswing and more time to produce higher angular velocities and forces. Furthermore, training intervention studies focusing on the aforementioned components have demonstrated enhancements in swing performance. Targeting multiple muscle groups, including those implicated via electromyography activation, and utilizing multiple modalities have proven effective at increasing club head speed. However, such multifaceted programs have made it difficult to determine the mechanisms that specifically contribute to performance gains. Despite these limitations, strength, power, and musculotendinous stiffness, particularly in the lower body, seem to be stronger determinants of club head speed and carry distance than flexibility. Furthermore, acute improvements can be induced using resistance-orientated warm-ups.