Development of an Abbreviated Model for Predicting Functional Movement Screen Score Within Tactical Populations.

ABSTRACT: Thompson, MB, Johnson, QR, Lindsay, KG, and Dawes, JJ. Development of an abbreviated model for predicting functional movement screen score within tactical populations. J Strength Cond Res 38(3): 607-611, 2024-The Functional Movement Screen (FMS) is a tool commonly used to identify compensations when performing 7 specific movement patterns. Timely administration of the full FMS is largely dependent on the practitioner's familiarity and experience with the screening battery. When working in populations that are time-poor (i.e., tactical professionals), administration of the full movement pattern battery is not always feasible. The purpose of this study was to determine which, if any, combination of movement patterns that comprise the FMS could be used to predict total score on this screen among first responders. Functional Movement Screen scores for 99 male subjects (mean ± SD; age: 37.55 ± 9.83 years; height: 180.38 ± 6.59 cm; and body mass: 97.87 ± 15.32 kg) and 9 female subjects (age: 33.22 ± 3.99 years; height: 172.11 ± 8.19 cm; and body mass: 83.99 ± 14.09 kg) from a single law enforcement and fire agency were used for this analysis. Subjects performed the full FMS, which consisted of the following movement patterns: deep squat (DS), hurdle step (HS), in-line lunge (ILL), shoulder mobility (SM), active straight leg raise (ASLR), trunk stability push-up (PU), and rotary stability (RS). A stepwise regression was used to determine the best predictors of the FMS 7-pattern model based on the model's R2. Cronbach's alpha and Guttman's lambda-2 were used to determine the reliability of the proposed models. The regression indicated that a 4-pattern model consisting of DS, ILL, SM, and PU was sufficient to predict approximately 84% of the full model (adjusted R2 = 0.84, p ≤ 0.001). This 4-pattern model was shown to be reliable with the 7-pattern model (α = 0.93, λ = 0.93). Using this modified version of the FMS may allow practitioners working in tactical populations a time-efficient method of identifying dysfunctional movement and determine whether the full 7-pattern model of the FMS should be considered.

Changes in Countermovement Vertical Jump Force-Time Metrics During a Game in Professional Male Basketball Players.

ABSTRACT: Cabarkapa, D, Johnson, QR, Cabarkapa, DV, Philipp, NM, Eserhaut, DA, and Fry, AC. Changes in countermovement vertical jump force-time metrics during a game in professional male basketball players. J Strength Cond Res 38(7): 1326-1329, 2024-As technology within elite basketball advances and is more available to sporting organizations, novel approaches for assessing and addressing athletic performance during practice or competition are being continuously explored. The aim of this investigation was to examine changes in neuromuscular performance during live basketball play. Eight professional male basketball players volunteered to participate in this study. The testing procedures were conducted during a pre-tournament camp over a span of 2 days. During the first day, the athletes were familiarized with the testing procedures, and baseline measurements were obtained. Using a uni-axial force plate system sampling at 1,000 Hz, each athlete performed 3 countermovement vertical jumps (CVJ) without an arm swing before proceeding with their regular training activities. During the second day of the pre-tournament camp, the athletes repeated identical CVJ testing procedures before the start of the first quarter and post-first, second, third, and fourth quarter of a simulated 5-on-5 basketball game. Repeated-measures testing design was used to examine statistically significant differences in various force-time metrics of interest in comparison to the baseline levels (p < 0.05). Besides a trivial decrease in eccentric mean force, the findings of this study revealed no statistically significant changes in any force-time metrics of interest within both eccentric and concentric phases of the CVJ (i.e., mean and peak force and power, jump height, impulse, velocity, and contraction time). Thus, we can conclude that these variables were not sensitive to acute fatigue, suggesting that the neuromuscular performances of professional male basketball players tend to remain unchanged throughout a 5-on-5 simulated game.

Acute effects of lower limb wearable resistance on horizontal deceleration and change of direction biomechanics.

This study aimed to investigate the acute effects of lower limb wearable resistance on maximal horizontal deceleration biomechanics, across two different assessments. Twenty recreationally trained team sport athletes performed acceleration to deceleration assessments (ADA), and 5-0-5 change of direction (COD) tests across three load conditions (unloaded, 2% of BW, 4% of body weight (BW)), with load attached to the anterior and posterior thighs and shanks. Linear mixed effect models with participant ID as the random effect, and load condition as the fixed effect were used to study load-specific biomechanical differences in deceleration mechanics across both tests. Primary study findings indicate that for the ADA, in the 4% BW condition, participants exhibited significantly greater degrees of Avg Approach Momentum, as well as significant reductions in deceleration phase center of mass (COM) drop, and Avg Brake Step ground contact deceleration (GCD) in both the 2% BW, and 4% BW condition, compared to the unloaded condition. In the 5-0-5 tests, participants experienced significant reductions in Avg Approach Velocity, Avg deceleration (DEC), and Stopping Time in the 4% BW condition compared to the unloaded condition. Similar to the ADA test, participants also experienced significant reductions in Avg Brake Step GCD in both the 2% BW and 4% BW conditions, and significant increases in Avg Approach Momentum in the 4% BW condition, compared to the unloaded condition. Therefore, findings suggest that based on the test, and metric of interest, the addition of lower limb wearable resistance led to acute differences in maximal horizontal deceleration biomechanics. However, future investigations are warranted to further explore if the use of lower limb wearable resistance could present as an effective training tool in enhancing athlete's horizontal deceleration and change of direction performance.

Comparison of vertical jump and sprint performances between 3 × 3 and 5 × 5 elite professional male basketball players.

Given its fast-growing popularity and unique on-court competitive demands, 3 × 3 basketball has captured a considerable amount of attention over recent years. However, unlike research focused on studying 5 × 5 basketball players, there is a lack of scientific literature focused on examining countermovement vertical jump (CMJ) and sprint performance characteristics of 3 × 3 athletes. Thus, the purpose of the present study was to compare force-time metrics during both eccentric and concentric phases of the CMJ and acceleration and deceleration capabilities between 3 × 3 and 5 × 5 top-tier professional male basketball athletes. Ten 3 × 3 and eleven 5 × 5 professional basketball players volunteered to participate in the present study. Upon completion of a standardized warm-up, each athlete performed three maximum-effort CMJs, followed by two 10 m sprints. A uni-axial force plate system sampling at 1,000 Hz was used to analyze CMJ force-time metrics and a radar gun sampling at 47 Hz was used to derive sprint acceleration-deceleration measures. Independent t-tests and Hedge's g were used to examine between-group statistically significant differences (p < 0.05) and effect size magnitudes. The findings of the present study reveal that 3 × 3 and 5 × 5 professional male basketball players tend to display similar neuromuscular performance characteristics as no significant differences were observed in any force-time metric during both eccentric and concentric phases of the CMJ (g = 0.061-0.468). Yet, prominent differences were found in multiple measures of sprint performance, with large effect size magnitudes (g = 1.221-1.881). Specifically, 5 × 5 basketball players displayed greater average and maximal deceleration and faster time-to-stop than their 3 × 3 counterparts. Overall, these findings provide reference values that sports practitioners can use when assessing athletes' CMJ and sprint performance capabilities as well as when developing sport-specific training regimens to mimic on-court competitive demands.

Sex-related Differences in Functional Movement Screen Scores Among Reserve Officers' Training Corps Cadets.

INTRODUCTION: The primary aim of Reserve Officers' Training Corps (ROTC) programs is to prepare cadets for future military service. To successfully complete one of these programs and perform active duty responsibilities, cadets must be able to complete a variety of physical tasks. Therefore, performing movement screening may be useful for identifying potential movement disparities that could lead to injury. The purpose of this investigation was to determine whether sex-related differences in movement patterns exist on the Functional Movement Screen (FMS). The FMS is a tool that uses seven functional movements to assess movement pattern deficits and asymmetries; deep squat, hurdle step, inline lunge (ILL), shoulder mobility, active straight-leg raise (ASLR), trunk stability pushup (TSPU), and rotary stability. MATERIALS AND METHODS: Archived data for 93 (male, n = 69; female n = 24) ROTC cadets were provided to the primary investigators for analysis. Independent t-tests (P < .05) were conducted to analyze differences in assessments between sexes. RESULTS: Significant differences between sexes were observed on the ILL (P = .014), ASLR (P < .001), and TSPU (P < .001). Females scored higher on both the ILL (2.13 ± 0.54) and ASLR (2.04 ± 0.69) compared with males (1.81 ± 0.52 and 1.48 ± 0.58). Males scored significantly higher (P ≤ .001) on the TSPU (2.57 ± .581) compared with females (2.00 ± .417). No significant differences were observed in the deep squat (P = .865), hurdle step (P = .829), shoulder mobility (P = .342), and rotary stability (P = .230) assessments. CONCLUSIONS: Sex differences in the ILL, ASLR, and TSPU may be because of greater mobility in the ankle and hamstrings and reduced upper-body muscle mass for females compared with males. Males performed better than females on the TSPU test. In conclusion, sex-related differences in FMS performance do exist within the ROTC population. Additionally, these differences should be taken into consideration when designing specific exercise programs for ROTC cadets.

Differences in countermovement vertical jump force-time metrics between starting and non-starting professional male basketball players.

With force plates being widely implemented for neuromuscular performance assessment in sport-specific settings and various force-time metrics being able to differentiate athletes based on their performance capabilities, the purpose of the present study was to examine the differences in countermovement vertical jump (CVJ) characteristics between starting and non-starting professional male basketball players (e.g., ABA League). Twenty-three athletes (height = 199.2 ± 7.7 kg, body mass = 94.2 ± 8.2 kg, age = 23.8 ± 4.9 years) volunteered to participate in the present investigation. Upon completion of a standardized warm-up protocol, each athlete performed three maximal-effort CVJs without an arm swing while standing on a uni-axial force plate system sampling at 1,000 Hz. Independent t-tests were used to examine statistically significant differences (p < 0.05) in each force-time metric between starters (n = 10) and non-starters (n = 13). No significant differences in any of the CVJ force-time metrics of interest were observed between the two groups, during both the eccentric and concentric phases of the movement (i.e., impulse, duration, peak velocity, and mean and peak force and power). Moreover, starters and non-starters demonstrated similar performance on CVJ outcome (e.g., jump height) and strategy metrics (e.g., countermovement depth). Overall, these findings suggest that at the professional level of play, the ability to secure a spot in the starting lineup is not primarily determined by the players' CVJ performance characteristics.

Differences in Stronger Versus Weaker Firefighters in Selected Measures of Power.

Firefighters are required to perform a wide array of physically demanding job tasks, such as forcible entry, charged hose advances and victim extractions. An adequate level of muscular strength and power are required to successfully perform these tasks. The purpose of this study is to investigate the differences in stronger and weaker firefighters in measures of power. Archived data for twenty-seven (age = 34.3 ± 7.9 yr, body height = 176.3 ± 7.2 cm, body mass = 89.4 ± 15.7 kg) full-time firefighters were analyzed. Participants were placed into one of two groups [i.e., stronger (HIGH) (n = 13) and weaker (LOW) (n = 14)], based on their relative isometric mid-thigh pull (IMTPr) performance. Power measures included counter-movement jump (CMJ) height, and peak anaerobic power in watts (PAPW). Significant mean score differences were not discovered between HIGH and LOW IMTPr groups on any measures of lower-body power. Moderate positive correlations were observed between IMTP and CMJ (r = .519; p = .01). This study identified significant differences in absolute and relative strength between firefighters who were able to lift at least 2.0× their bodyweight versus those who were not. Additionally, absolute strength (as assessed by the IMTP) was significantly and positively correlated to CMJ height when compared to their weaker counterparts. These findings may provide insight into approaches for improving occupational performance and durability through the physical development of firefighters via strength and conditioning programs which focus on developing absolute strength, relative strength, and power.

Relationships between Lower-body Power, Sprint and Change of Direction Speed among Collegiate Basketball Players by Sex.

The purpose of this study was to determine if significant relationships exist between absolute and relative lower-body power and selected measures of speed among male and female collegiate basketball players. Archived performance testing data from 29 (male = 14; female = 15) NCAA division II collegiate basketball players were used for this analysis. These measures included lane agility, 10-yard sprint, and shuttle run time (sec). A Pearson's correlation coefficient was used to determine if significant relationships existed between measures of lower-body power and linear sprint time, change of direction speed (CODS), and shuttle performance. Statistical significance was set a priori at p ≤ 0.05. A significant large correlation was found between absolute power and lane agility (r = 0.54, p = 0.05) among male players. No significant correlations were found between absolute or relative power for 10-yard sprint times, lane agility, or shuttle run performance (p > 0.05). Females showed no significant correlations between relative power and lane agility (r = -0.25, p = 0.37) or 10-yard sprint (r = -0.47, p = 0.08), but did show a significant large correlation (r = -0.64, p = 0.01) between relative power and shuttle run performance. Generating high amounts of relative power is vital in intermittent team sports such as basketball. In particular, this study provided evidence that relative power in female collegiate basketball players is significantly related to shuttle run ability.

The Impact of Aquatic Based Plyometric Training on Jump Performance: A Critical Review.

There is evidence to suggest that aquatic plyometric training (APT) may be an effective and safer alternative to traditional land-based plyometric training (LPT) when training to increase jump performance. The aim of this review was to critically examine the current literature regarding the effects of APT vs. LPT on jump performance in athletic populations. Key terms were employed in five separate databases to complete the current review. Available articles were screened for inclusion and exclusion criteria to determine which studies were deemed eligible for review. Outcome measure in these studies included those assessing lower extremity power and jump performance (i.e., drop jumps, broad jumps, sergeant jumps, repeated countermovement jumps, and vertical jumps). All but one of the studies included in this critical review showed significant improvements in jump performance after LPT and APT interventions. Both LPT and APT groups experienced similar increases in jump performance and lower-body power, pre- to post-test, in the majority of the studies examined in this review. LPT and APT have the ability to improve lower extremity explosive strength and jump performance within athletic populations. Improvements in lower body power may improve overall athletic performance. Observations from this review may be used by sport coaches, strength coaches, and athletes alike to weigh the pros and cons of both forms of plyometric training. Observations from this review may also be used to weigh the pros and cons of APT over LPT in terms of reducing risk of injury.

Relationships of Lower-body Power Measures to Sprint and Change of Direction Speed among NCAA Division II Women's Lacrosse Players: An Exploratory Study.

This study sought to determine if significant relationships exist between lower-body power measures to sprint and change of direction speed (CODS) in Division II collegiate women's lacrosse athletes. Archived data for 17 NCAA Division II female lacrosse athletes was provided to the investigators for analysis. Jumping performance was assessed using a countermovement jump (CMJ), squat jump (SJ), and standing broad jump (SBJ). Sprint speed was measured at 10m and 30m, of a 30m sprint. CODS was evaluated using a T-Test (TT), a modified T-Test (MTT), and the 5-0-5 Agility Test (5-0-5). No significant relationships were found between absolute power measures and any sprint or CODS tests. However, relative power (relative CMJ and SJ) had significant relationships with all CODS and sprints speeds above 10m. Only the CMJ and relative CMJ were related to 10m sprint speed. SBJ distance had significant relationships with all CODS tests and 30m speed, while relative SBJ distance significantly correlated with 5-0-5 speed. Relative lower-body power was significantly related to speed and CODS in Division II female lacrosse athletes. Strength and conditioning professionals should focus on lower-body power development as a key component in preparing female lacrosse athletes for their sport.

Heart Rate Responses during Simulated Fire Ground Scenarios among Full-Time Firefighters.

Simulated fire ground scenarios (SFGS) provide firefighters with an opportunity to maintain skills, receive feedback, and optimize performance. Although there is extensive research on heart rate (HR) changes in the firefighter population, few examine the differences between positions. Firefighters are primarily responsible for fire suppression and control (23), officers for emergency operations and organizational management, paramedics for providing on-scene emergency medical care, and drivers are responsible for driving the fire apparatus. Utilizing HR analysis to quantify the physical demands of SFGS among firefighting crews by position. Sixty-seven male (age: 38.97 ± 9.17; ht: 177.99 ± 6.45 cm. wt: 88.83 ± 13.55 kg) firefighters (FF) participated in this investigation. FF crews performed two SFGS involving the suppression and control of a structural fire. Participants were outfitted with heart rate (HR) monitors and average heart rate (HRavg) and maximum heart rate (HRmax) data were collected for each of the two SFGS. Significant differences were observed for Age (P = 0.01), APMHR (P = 0.01), HRmax1 (P = 0.04), and HRmax2 (P = 0.04) in which firefighters had higher values for Age-predicted maximal heart rate (APMHR), HRmax1, HRmax2 compared to the officers. SFGS can be very physically demanding events that may elicit maximal or near maximal HR responses regardless of position. Based on the metabolic demands of these events and the individual firefighter's capabilities, this information can be used to develop resistance training and conditioning programs that optimize performance at maximal or near maximal heart rates.

Body Composition Comparison of Upper- and Underclass Reserve Officers' Training Corps Cadets.

INTRODUCTION: Body composition (BC) measurements are used to determine qualification for enlistment and to ensure active members are meeting standards. Although there is extensive research on BC in active-duty military, very few have examined ROTC cadets. The purpose of this study was to identify and quantify differences in BC between freshman/sophomore [underclass (UND)] and junior/senior [upperclass (UPP)] ROTC cadets by using bioelectrical impedance spectroscopy (BIS).METHODS: UND (N = 21) and UPP (N = 15) Air Force ROTC cadets volunteered for this study. BIS was used to measure fat mass percentage (FM%), fat free mass percentage (FFM%), total body water percentage (TBW%), extracellular fluid percentage (ECF%), and intracellular fluid percentage (ICF%). Separate one-way ANOVAs were run between UND and UPP for all dependent variables with a Bonferroni correction factor. Additionally, a Pearson correlation between abdominal circumference (AC) and FM% was conducted.RESULTS: No significant differences were observed between the UND and UPP groups' BMI. However, significant differences were observed for ECF%, ICF%, TBW%, FFM%, and FM% in which the UPP had a higher TBW%, ICF%, FFM%, and a lower ECF% and FM% compared to the UND.CONCLUSIONS: This study observed significant differences in BC across class ranks in ROTC cadets. Findings from this study suggest that due to an increased exposure to ROTC training, UPP cadets have a more ideal body composition (FFM% and FM%) when compared to UND cadets.Johnson QR, Mackey CS, Muddle TD, Smith DB, DeFreitas JM. Body composition comparison of upper- and underclass Reserve Officers Training Corps cadets. Aerosp Med Hum Perform. 2019; 90(9):813-818.