Justin J Merrigan

Justin J Merrigan
The Ohio State University | OSU · Human Performance Collaborative

Doctor of Philosophy

About

75
Publications
19,239
Reads
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219
Citations
Introduction
Overall, my focus is provide evidence on program design and assessment for performance in men and women. To do so, I’ve assessed the mechanisms and applicability of muscular potentiation and damage through eccentric loading, as well as sex specific responses to resistance training and performances in physical fitness tasks. Collectively, with current research on biomechanical responses to load carriage, my hope is to identify potential mechanisms for reducing injury risk in tactical settings.
Education
August 2017 - December 2020
George Mason University
Field of study
  • Kinesiology
August 2015 - May 2017
George Mason University
Field of study
  • Exercise, Fitness, and Health Promotion
August 2010 - May 2014
Lock Haven University of Pennsylvania
Field of study
  • Fitness Management

Publications

Publications (75)
Poster
Full-text available
Comparison of heart rate monitors (Polar H10, Polar Verity, Polar Grit-X, Garmin HRM-Pro, Garmin Fenix-6) to ECG during tactical movements and other various exercises.
Article
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Background: The coronavirus disease 2019 (COVID-19) pandemic altered lifestyles and impacted mental health of many adults. Engaging in physical activity, avoiding prolonged sitting, and consuming a healthy diet improve mental health. The current study investigated the association between health-related lifestyle behaviors on feelings of anxiety and...
Article
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With the growing prevalence of commercial force plate solutions providing automated force-time curve analysis, it is critical to understand the level of agreement across techniques. Thus, this study directly compared commercial and custom software analyses across force-time curves. Twenty-four males and females completed six trials of countermoveme...
Article
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Accentuated eccentric loading (AEL) employs heavier load magnitudes in eccentric actions than concentric actions of complete stretch-shortening cycles. In doing so, unique neuromuscular and molecular responses are expected to result in acute post-activation performance enhancements, as evidenced by increased movement velocity or power. Improvements...
Article
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The primary purpose was to simplify external load data obtained during Division-I basketball competitions via principal component analysis (PCA). A secondary purpose was to determine if the PCA results were sensitive to load demands of different positional groups (POS). Data comprised 229 observations obtained from 10 men’s basketball athletes part...
Article
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There has been limited research to explore the use of body tempering and when the use of this modality would be most appropriate. This study aimed to determine if a body tempering intervention would be appropriate pre-exercise by examining its effects on perceived soreness, range of motion (ROM), and force production compared to an intervention of...
Article
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Monitoring external loads may minimize injury risk and improve physical performance. The purpose was to describe the external loads of a men’s collegiate soccer team during practice and games at the start of in-season play. In the first 2 weeks of the competitive season, National Collegiate Athletic Association Division I soccer athletes (n=19; mea...
Article
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Firefighting is a mentally and physically demanding profession which is compounded by poor sleep due to shift schedules commonly used by fire departments. Compared to other professions, firefighters are at high risk for musculoskeletal injuries, mental illnesses, and cardiovascular diseases. The purpose of this study was to systemically review the...
Article
BACKGROUND: Law enforcement recruits (LER) often encounter shoulder injuries, which may cause attrition from academies. Investigating required upper body muscular fitness may inform of muscular balance around shoulder joints through anterior and posterior ratios in LER. OBJECTIVE: To investigate push to pull ratios (P2P) and factors related with P...
Article
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This study aimed to reduce the dimensionality of countermovement jump (CMJ) force-time characteristics and evaluate differences among positional groups (Skills, Hybrid, Linemen, Specialists) within National Collegiate Athletic Association (NCAA) Division I American football. Eighty-two football athletes performed two maximal effort, no arm-swing, C...
Article
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The purpose was to investigate the effect of load and fatigue on landing forces and mechanics. Thirteen Department of State special agents first completed drop jump testing, a maximal treadmill test, and another round of drop jump testing. During drop jump testing, agents performed 3 maximal effort drop jumps from 30 cm with body mass only (unloade...
Article
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The purpose of this study was to indicate the most influential force-time metrics on countermovement jump (CMJ) height using multiple statistical procedures. Eighty-two National Collegiate Athletic Association Division I American football players performed two maximal effort, no arm-swing, CMJs on force plates. The average absolute and relative (i....
Article
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Human performance optimization of tactical personnel requires accurate, meticulous, and effective monitoring of biological adaptations and systemic recovery. Due to an increased understanding of its importance and the commercial availability of assessment tools, the use of heart rate variability (HRV) to address this need is becoming more common in...
Article
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Force plate assessments, such as countermovement jumps and isometric mid-thigh pulls, examine performances (e.g., jump height, force, power) and movement strategies (e.g., asymmetries, durations), and are best suited to characterize and monitor physical capabilities, not predict injuries. To begin applying force plate technologies, users must first...
Article
Fields, JB, Merigan, JM, Gallo, S, White, JB, and Jones, MT. External and internal load measures during preseason training in men collegiate soccer athletes. J Strength Cond Res 35(9): 2572-2578, 2021-Collegiate athletes are exposed to high volume loads during preseason training. Monitoring training load can inform training and recovery periods. Th...
Poster
Full-text available
Annual estimates are that approximately 34% of law enforcement recruits (LER) fail to complete the academy due to injury or inability to meet physical standards. Shoulder injuries are a commonly cited injury which can cause LER to leave the police academy. It has been suggested that anterior ('push') and posterior ('pull') musculature should be bal...
Poster
Full-text available
Poor sleep is well documented in firefighters. Shift schedules combined with occupational requirements are known to be contributing factors to poor chronic and acute sleep of firefighters. The negative effects of poor sleep on firefighters were documented in a 2007 review supported by the International Association of Fire Chiefs and the United Stat...
Poster
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Obtaining sufficient sleep is beneficial for numerous aspects of health. Despite current sleep recommendations, acute disruptions in sleep duration are inevitable for most. While extreme sleep deprivation impairs motor control and coordination of movement, sleep extension also impacts these same parameters. Prior research suggests that acute change...
Article
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The purpose was to evaluate neuromuscular fatigue’s effect on unloaded and loaded counter-movement jump (CMJ) force-time characteristics during high intensity tactical training. Eighteen male and sixteen female Marines completed 2 maximal effort CMJs, in unloaded (PVC pipe) and loaded (10-kg weight vest and 20-kg barbell) conditions, prior to, and...
Article
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Laboratory assessments of maximal oxygen uptake (VO2max) are considered the “gold standard” for ascertaining cardiovascular fitness, but they are not always practical for use in team sport settings. Therefore, the purpose of the current study was to compare the criterion assessment of VO2max on a treadmill to the progressive, multistage 20-m shuttl...
Article
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BACKGROUND: Law enforcement officers experience high stress levels and perform various physical tasks. Thus, law enforcement academies emphasize physical fitness training and assessment. OBJECTIVE: To examine fitness test-performances and determine which entry-level fitness components best predict likelihood of successful law enforcement academy g...
Article
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This study examined the effects of accentuated eccentric loading (AEL) on bench press velocities across a spectrum of concentric and eccentric loads. Ten strength trained men (bench press one-repetition maximum (1-RM): 124.3 ± 19.4 kg; relative strength ratio: 1.5 ± 0.2 kg∙body mass−1) participated. Subjects completed bench press repetitions using...
Article
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Background: The COVID-19 pandemic has changed our working environment and divided workers into essential or nonessential statuses. Employment status is a major factor determining the amount of physical activity performed. Our purpose was to understand how employment status affects physical activity and sitting time. Methods: Between April 13 and...
Article
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The purpose was to examine effects of sex, drop height, and external loads on drop jump mechanics in Reserve Officer Training Corps cadets and whether findings were associated with strength. Males (n=14) and females (n=12) completed maximal isokinetic concentric (slow-C, fast-C) and eccentric (slow-E, fast-E) knee extensions and flexions at 60°·s−1...
Article
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Low-income Latino children are at high risk for obesity and associated comorbidities. Considering the health benefits of proper sleep habits and physical activity, understanding the patterns , or the relationship between these modifiable factors may help guide intervention strategies to improve overall health in this population. Thus, the purpose w...
Presentation
Full-text available
This is the 3rd edition of a series of bi-monthly presentations that consists of article summaries and their tactical relevance on topics including, but not limited to, training load, recovery, biomechanical force production, data science, cognitive function, wellbeing, wearable technologies, and sleep. Our goal, as the team at Rockefeller Neurosci...
Article
Full-text available
The purpose was to evaluate the acute effects of accentuated eccentric loading (AEL) on bench press velocity and subsequent perceived effort (RPE) and soreness. Resistance-trained men (n=8) and women (n=2) completed 4 sets of 5 bench press repetitions with AEL and traditional loading (TL) using concentric loads of 50% (AEL50, TL50) and 65% (AEL65,...
Article
Monitoring athlete training load is important to training programming and can help balance training and recovery periods. Further, psychological factors can affect athlete’s performance. Therefore, the purpose was to examine the relationship between external load and self-reported wellness measures during soccer pre-season. Collegiate men soccer at...
Article
Full-text available
Abstract: The purpose of this study was to evaluate intrasession reliability of countermovement jump (CMJ) and isometric mid-thigh pull (IMTP) force–time characteristics, as well as relationships between CMJ and IMTP metrics. Division I sport and club athletes (n = 112) completed two maximal effort CMJ and IMTP trials, in that order, on force plate...
Article
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Citation: Hornsby, W.G.; Tice, A.L.; Stone, J.D.; Merrigan, J.J.; Hagen, J.; Wagle, J.P.; Cunanan, A.J.; Stone, M.H. Publisher's Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations. Abstract: The purpose of this longitudinal, descriptive study was to observe changes in maximal strength meas...
Article
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A necessarily high standard for physical readiness in tactical environments is often accompanied by high incidences of injury due to overaccumulations of neuromuscular fatigue (NMF). To account for instances of overtraining stimulated by NMF, close monitoring of neuromuscular performance is warranted. Previously validated tests, such as the counter...
Presentation
Full-text available
This is the first edition of a series of bi-monthly presentations that consists of article summaries and their tactical relevance on topics including, but not limited to, training load, recovery, biomechanical force production, data science, cognitive function, wellbeing, wearable technologies, and sleep. Our goal, as the team at Rockefeller Neuros...
Presentation
Full-text available
This is the first edition of a series of bi-monthly presentations that consists of article summaries and their tactical relevance on topics including, but not limited to, training load, recovery, biomechanical force production, data science, cognitive function, wellbeing, wearable technologies, and sleep. Our goal, as the team at Rockefeller Neuros...
Article
The purpose was to investigate the effect of rest-redistribution (RR) on muscle damage after eccentric knee extensions. After 2 weeks of eccentric familiarization, 11 resistance-trained men performed 2 work-matched isokinetic unilateral eccentric knee extension protocols at 60°·s using a crossover design, separated by 7 days. Subjects performed 40...
Poster
Full-text available
PURPOSE To investigate relationships among common upper body fitness assessments, body fatness, and push to pull ratios in Prince William County firefighters (FF) and police officers (PO). METHODS § 47 Professional firefighter (FF) and police officers (PO) employed by Prince William County (PWC) Virginia o FF (n=37; male; n=33; female: n=4) o PO (n...
Article
Full-text available
Shoulder joint injuries are common for professional firefighters. A potential cause of shoulder injury is an imbalance between anterior (‘push’) and posterior (‘pull’) shoulder joint musculature. Understanding what contributes to these imbalances may help to identify areas needing improvement. The purpose of this study was to investigate different...
Article
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Redistributing long inter-set rest intervals into shorter but more frequent rest intervals generally maintains concentric performance, possibly due to improved energy store maintenance. However, eccentric actions require less energy than concentric actions, meaning that shorter but more frequent sets may not affect eccentric actions to the same deg...
Presentation
Full-text available
The primary purpose was to evaluate the acute effects of accentuated eccentric loading (AEL) on bench press repetition velocity and power and subsequent perceived effort and soreness. A secondary purpose was to investigate whether an individual’s relative strength influenced such effects of AEL. Resistance-trained men (n=8) and women (n=2) complete...
Article
Full-text available
This study evaluated the reliability and concurrent validity of the OUTPUT sports inertial unit to measure concentric velocity of free-weight back squat and bench press exercises. Eleven men and women performed back squat and bench press one-repetition maximum (1-RM) testing. One week later, subjects performed three repetitions of each exercise wit...
Poster
Full-text available
Police officers experience high levels of stress and as a result the required police academy is aimed to train recruits to handle physical and psychological stressors. Police departments undertake a large financial commitment with estimated costs reaching upwards of $100,000 per recruit. Since initial fitness testing is typically required it would...
Article
Full-text available
The purpose was to determine differences in time under tension, cortisol, inflammation, and perceived soreness between accentuated eccentric (AEL) and traditional loading (TRA) resistance exercise protocols. Resistance-trained men (n=21) completed the AEL and TRA protocols in random order, separated by 48 hours (sets*reps@eccentric/concentric): AEL...
Article
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The purpose was to investigate whether whole-body vibrations (WBV) effect on force-time 1 characteristics is dependent upon time and sex. Subjects (men, n=18; women, n=18) 2 performed a static quarter squat with WBV (frequency: 30Hz; amplitude: 2-4 mm) and 3 without for 5 x 30 second repetitions (1:1 WBV:rest). Next, they performed 2 sets of 3 4 re...
Presentation
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Regardless of sex and physical stature, tactical athletes are required to execute physical tasks during training and operational scenarios while wearing equipment of similar weight. The effect of external loads upon performance during jumping tasks and vertical ground reaction forces when landing is unclear. Further, it is important to determine th...
Poster
Full-text available
The incidence of lower extremity injury in Reserve Officer Training Corps (ROTC) cadets is 10% greater for women and the majority occur at the thigh or knee. Since, likelihood of injury may be dependent upon absolute muscle strength and asymmetries among muscle groups, evaluation of quadricep and hamstring function is imperative. In consideration o...
Presentation
Full-text available
For tactical athletes, physical performances and injury rates are influential to mission success and personnel safety. Non-combat musculoskeletal injuries make up the majority of warfighter injuries and may stem from the interaction between load carriage requirements and neuromuscular performance capabilities. Although strength may relate to jump p...
Poster
Full-text available
In tactical athletes, sex differences have been reported for incidence of stress fractures and physical fitness performances, possibly as a result of differing bone mineral density (BMD, bone content per area) and lean body mass (LBM). Associations with health, appearance, and performance make a relatively low body fat (BF%) desirable within this p...
Article
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International Journal of Exercise Science V(i): X-Y, YEAR. Monitoring internal load provides useful and non-invasive markers of training stress and adaptation. However, the relationship between internal load measures across a competitive window remains inconclusive and limited. The purpose of this study was to report various internal load measures,...
Article
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Purpose: To identify acute effects of a single accentuated eccentric loading (AEL) repetition on subsequent back-squat kinetics and kinematics with different concentric loads. Methods: Resistance-trained men (N = 21) participated in a counterbalanced crossover design and completed 4 protocols (sets × repetitions at eccentric/concentric) as follo...
Article
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The purpose was to examine acute effects of rest redistribution on perceptual, metabolic, and hormonal responses during back squats. Twelve resistance-trained women (training age 5±2 years; one-repetition maximum (1-RM) per body mass, 1.6±0.2) performed traditional (TS, 4 sets of 10 repetitions with 120 seconds inter-set rest) and rest-redistributi...
Article
Full-text available
Given the high prevalence of obesity in Latino children and potential health risks, the purpose of this study was to: 1) evaluate relationships among metabolic-risk, fitness, and body fatness; 2) determine sex differences in cardio-metabolic risk factors and fitness of obese children of Latino descent. Sixty children (boys, n = 39, 7.8 ± 1.5 years;...
Article
Full-text available
Given the high prevalence of obesity in Latino children and potential health risks, the purpose of this study was to: 1) evaluate relationships among metabolic-risk, fitness, and body fatness; 2) determine sex differences in cardio-metabolic risk factors and fitness of obese children of Latino descent. Sixty children (boys, n = 39, 7.8 ± 1.5 years;...
Presentation
Full-text available
This presentation begins with a brief overview of eccentric training methods, including the benefits, comparisons to concentric actions, exercise induced muscle damage, and the repeated bout effect. Then findings are presented on the effects of accentuated eccentric loading on barbell velocity, force, and power, as well as subsequent inflammatory a...
Article
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Structured Summary Introduction: Due to the physical fitness requirements of Military Occupational Specialties (MOS) within the United States 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...
Article
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The purpose was to investigate the effects of using compound sets during a 12-week lower body resistance training program on muscle strength, endurance, hypertrophy, architecture, and soreness. Thirty-one recreationally active females were randomly assigned into one of three groups: traditional sets, compound sets, or control. The training groups p...
Poster
Full-text available
Accentuated eccentric loading (AEL) may elicit muscle damage, and result in increased levels of perceived soreness and fatigue. Momentary muscular fatigue and high levels of time under tension (TUT) are commonly reported in the literature. However, the effect of supramaximal AEL, during the initial repetition (rep) of a set, upon TUT and self-asses...
Poster
Full-text available
Accentuated eccentric loading (AEL) may potentiate muscle activity and lead to enhanced concentric velocity, but results vary with lifting tempo and eccentric load. Weight releasers can be used to implement AEL, but due to their nature of use, evaluation of velocity generally is limited to one repetition (rep). However, the velocity of non-AEL reps...
Poster
Full-text available
Sex, low income, insufficient physical activity levels, and excess body fat have been associated with low physical fitness levels in children. Further, children of Latino descent are more likely to be obese than their white counterparts. Yet, little is known about fitness abilities of obese, Latino children. PURPOSE: To evaluate the relationship be...
Poster
Full-text available
Family-based pediatric obesity treatment programs, which include organized physical activity, have become increasingly popular and have been effective in reducing adiposity and increasing fitness among children. Yet, treatment programs remain limited for Latino children, a population disproportionally affected by obesity. PURPOSE: To evaluate the e...
Poster
Sex differences in muscular strength and power are often diminished when accounting for fat free mass or muscle volume. However, the evaluation of sex differences in rate of force development (RFD) and the role of fat free mass on potential differences have not been fully investigated. PURPOSE: To examine sex differences in kinetics (forces) during...
Article
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Purpose: To examine rest-redistribution (RR) effects on back-squat kinetics and kinematics in resistance-trained women. Methods: Twelve women from strength and college sports (5.0 ± 2.2 y training history) participated in the randomized crossover-design study with 72 h between sessions (3 total). Participants completed 4 sets of 10 repetitions u...
Article
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PurposeMuscular strength is suggested to be dependent upon muscle characteristics. Yet, sex-specific relationships of muscle characteristics to strength in the resistance-trained require investigation. Therefore, the purpose was to evaluate sex differences in muscle characteristics and isometric strength in the elbow extensors, as well as their res...
Article
The purpose was to examine load-velocity and load-power relationships of back squat in resistance-trained men (n=20, 21.3 ± 1.4 yrs, 183.0 ± 8.0 cm, 82.6 ± 8.0 kg, 11.5 ± 5.0 % total body fat) and women (n = 18; 20.0 ± 1.0 yr; 166.5 ± 6.9 cm; 63.9 ± 7.9 kg, 20.3 ± 5.0 %BF). Body composition testing was performed followed by determination of back sq...