Secondary Logo

Relationship of Strength and Conditioning Metrics to Success on the Army Ranger Physical Assessment Test

Barringer, Nicholas D.1; McKinnon, Craig J.2; O'Brien, Nicholas C.3; Kardouni, Joseph R.2

The Journal of Strength & Conditioning Research: April 2019 - Volume 33 - Issue 4 - p 958–964
doi: 10.1519/JSC.0000000000003044
Original Research
Free
SDC

Barringer, ND, McKinnon, CJ, O'Brien, NC, and Kardouni, JR. Relationship of strength and conditioning metrics to success on the army ranger physical assessment test. J Strength Cond Res 33(4): 958–964, 2019—The purpose of our study was to compare standard strength and conditioning assessments in the Ranger Athlete Warrior (RAW) assessments to a tactical assessment of the Ranger Physical Assessment Test (RPAT) to determine what influence, if any, that they may have on the RPAT outcome. We analyzed RAW and RPAT data on 1,141 soldiers attempting the Ranger Assessment and Selection Program I (RASP I) for entrance into the 75th Ranger Regiment as part of their routine program data collection from July 2014 to July 2017. We found better performance in the broad jump, pull-ups, and average 300-yard shuttle time was associated with improved odds of passing the RPAT. For every increasing 2.54 centimeters in broad jump, the odds of passing the RPAT increased by 4% (OR = 1.04, 95% CI [1.01–1.07]). Each additional pull-up was associated with 6% better odds (OR = 1.06, 95% CI [1.01–1.12]) of passing the RPAT, and every second faster in the 300-yard shuttle was associated with 9% better odds of passing the RPAT (OR = 1.09, 95% CI [1.03–1.14]). The results of this study indicate that lower-body power, pulling strength, and anaerobic conditioning seemed to have the greatest influence on RPAT success. Our current results provide guidance to Strength Coaches or TSAC-Fs preparing tactical athletes for this specific or similar tactical assessment as better performance was found for tactical athletes with greater lower-body power, pulling strength, and anaerobic endurance.

1Military Nutrition Division, U.S. Army Research Institute of Environmental Medicine, Natick, Massachusetts;

2Military Performance Division, U.S. Army Research Institute of Environmental Medicine, Natick, Massachusetts; and

3Ranger Athlete Warrior Program, 75th Ranger Regiment, Fort Benning, Georgia.

Supplemental digital content is available for this article. Direct URL citations appear in the printed text and are provided in the HTML and PDF versions of this article on the journal's Web site (http://journals.lww.com/nsca-jscr).

Back to Top | Article Outline

Introduction

The 75th Ranger Regiment is part of the US Army Special Operations Command and is considered the Army's premier raid force. As part of being an elite unit, the 75th has a history of innovation, physical fitness, and training such as in the development of the Ranger Athlete Warrior (RAW) program under then Regimental Commander COL Paul LaCamera. The program is a holistic approach to taking care of the tactical athlete through appropriate physical training, sports medicine, nutrition, and mental toughness (8). The RAW program is now nested under the US Army Special Operations Command (USASOC) Human Performance Program, which falls under the United States Special Operations Command (USSOCOM) Preservation of the Force and Family initiative. As part of this program, Strength Coaches are used in Human Performance Training Centers (HPTC), and Rangers undergo the following physical performance–based assessments battery: a 3 repetition maximum trap bar deadlift, broad jump, 5-10-5 agility shuttle, pull-ups, heel claps, metronome push-ups, and two 300-yard shuttles with 2-minute rest between. The goal of this battery is to have a broad assessment of the physical performance characteristics of the Ranger. In addition to these physical performance assessments, the 75th also has a tactical physical assessment called the Ranger Physical Assessment Test (RPAT) that involves a tactical assessment underload. The standard for this event is completion in under 40 minutes (39:59). Although there is no specific research on the validity of the RPAT as an assessment, the assessment was developed by Rangers as a model similar to tasks that they might have to complete during a combat operation based on previous experience. Because tactical athletes require a level of fitness and technical skill commensurate with their occupational requirements (9), and strength and power are important in high-intensity military tasks (6), our objective was to compare the outcomes on the individual and combined physical performance assessment tasks with RPAT success to determine what influence, if any, that they may have on the RPAT outcome. By determining how these physical performance metrics relate to tactical performance, we can provide more specific guidance on training methodologies that provide the most benefit to RPAT success.

Back to Top | Article Outline

Methods

Experimental Approach to the Problem

The analyzed data were collected by the Human Performance Program Coordinator at the 75th Ranger Regiment from July 2014 to July 2017 on individual soldiers undergoing the Ranger Assessment and Selection Program I.

Back to Top | Article Outline

Subjects

All data were deidentified before sending to the US Army Research Institute of Environmental Medicine (USARIEM). The project was exempt from approval by USARIEM Office of Research Quality Control (ORQC) before commencement of analysis. It was a collaborative effort among the 75th Ranger Regiment, US Army Special Operations Command (USASOC), and researchers from the Military Nutrition and Military Performance Divisions at USARIEM.

Back to Top | Article Outline

Procedures

The RAW assessment tasks were all performed on the same day inside a covered climate controlled facility, whereas the RPAT was conducted on a separate day outside in a training area located in Columbus, GA. An average of 5 minutes of rest was provided between each RAW assessment task (see RAW assessement, supplemental digital content 1: http://links.lww.com/JSCR/A125) . All tasks were monitored and recorded by a Certified Strength and Conditioning Specialist (CSCS) unit human performance coach. The RAW assessments were conducted in a physical training uniform consisting of shorts, t-shirt, and tennis shoes, and the RPAT was conducted in combat uniform with boots, helmet, and body armor weighing ∼20 lbs (see RPAT assessment, supplemental digital content 2: http://links.lww.com/JSCR/A126).

The athletic and tactical assessments were the following as described in the RAW Assessment Task Conditions and Standards document dated 2016 (8) and conducted in the following order:

Back to Top | Article Outline

Task 1: Standing Broad Jump

The purpose of the test is to measure total-body power.

Back to Top | Article Outline

Task 1: Conditions

Given a solid flat athletic surface, a tape measure (or marked lines), and a line to mark foot placement (athletic tape is sufficient). Ranger will have 3 attempts to jump as far as they can.

Back to Top | Article Outline

Task 1: Standards

Subejcts will stand with the toes behind the line. The Ranger will then jump as far as possible and stick the landing without moving the feet or allowing the hands or any other body parts to touch the ground. The measurement will be taken from the heel of the closest foot. The grader will record only the farthest jump and measured distance between the feet to the nearest inch (e.g., 8 ft 5 in).

Back to Top | Article Outline

Task 2: 5-10-5 Shuttle Run

The purpose of the test is to measure speed, agility, and quickness.

Back to Top | Article Outline

Task 2: Conditions

Given a flat, athletic surface with a length of 10 yards, 3 lines (can be made from athletic tape) 5 yards apart from the center.

Back to Top | Article Outline

Task 2: Standards

The Ranger straddles the middle line with an evenly spaced stance and the feet parallel to the line. When the Ranger is ready, he will go into a three-point stance with the hand on the line in the direction that he is going to be moving. He will start by going to the right and run 5 yards and touch the line with a hand. He then turns and runs 10 yards to his left and will touch the other line with a hand. Ranger will then turn and run the final 5 yards through the center line. Time is measured from when the Ranger makes his first movement to when he passes the start/stop line with any part of his body. The test is repeated a second time to the left, and both times are recorded. The average of the 2 times is the time that is scored. Time is measured to the nearest one hundredth of a second (e.g., 4.95 seconds).

Back to Top | Article Outline

Task 3: Deadlift 3 Repetition Maximum

The purpose of this test is to measure total-body lift strength from the ground.

Back to Top | Article Outline

Task 3: Conditions

Given a 45-lb trap bar (hexagon shape with neutral handles in line with the rest of the bar) with plates to load on each side.

Back to Top | Article Outline

Task 3: Standards

Subjects should work up weight as needed while ensuring that form is correct. When the Ranger reaches a weight they decide will be their first attempt, they stand inside the trap bar with their preferred foot width. To initiate the test, they squat down into position with a straight back and assume a firm and centered grip on the bar to prevent the bar from rotating. The Ranger will lift the bar off the ground until standing fully erect, but not hyperextended. A pause in the up (lockout) position is allowed. The Ranger then returns the bar to the ground under control. A pause in the bottom position of no greater than 3 seconds is allowed, but not required, to reset the start position as long as the hands maintain in contact with the bar. The test set is complete when they lower the bar from the third consecutive rep. The event is terminated when the Ranger reaches their 3 repetition maximum, fails to maintain upward movement of the bar once the lift is started, or fails to maintain a safe lifting position as determined by the grader (which should be a RAW staff member). The recorded number is the final weight achieved in pounds.

Back to Top | Article Outline

Task 4: Pull-Up

The purpose of this test is to measure muscular strength and endurance of the grip and upper-body pulling muscles in relation to body mass.

Back to Top | Article Outline

Task 4: Conditions

Given a straight pull-up bar that allows for full-body extension without the feet touching the ground.

Back to Top | Article Outline

Task 4: Standards

On the command “ready,” subjects should move to a freehang position with arms straight and elbows locked, using an overhand grip, with the thumbs placed over the bar. Next, they should pull the body upward until the chin is over the bar. Subjects will need to return to the straight-arm hang position with elbows locked for the completion of one repetition. They will repeat this pull-up movement as many times as possible. The body should maintain a generally straight line from head to heel. If the Ranger generates any additional movement to create momentum (i.e., kipping), the pull-up involved will not be counted. The grader should count out to load the number of repetitions to let the Ranger know whether any reps are not being counted and provide concise cues to let them know what they need to fix. The number of correct repetitions is recorded.

Back to Top | Article Outline

Task 5: Metronome Push-up

The purpose of this test is to measure the muscular endurance of the upper-body pushing and core muscles.

Back to Top | Article Outline

Task 5: Conditions

Given a solid, athletic surface and a metronome set to 1-second interval (60 beats per minute).

Back to Top | Article Outline

Task 5: Standards

On the command “Get Ready,” subjects should assume the kneeling front-leaning rest position. On the command “Get Set,” the subjects should assume the front-leaning rest position. On the command “Go,” the subjects should lower the body until the upper arm is parallel to the ground. On the next metronome sound, they should immediately return to the front-leaning rest. On the next metronome should, they should immediately return to the lower position described above. When Ranger can no longer stay with the metronome cadence, the test is terminated and the last number of correct repetitions is recorded. Ranger cannot skip a beat on this test. The regular Army Physical Fitness Test standards are used to grade the push-up (i.e., body position, lower, and upper position). The body must maintain in a straight line throughout. If Ranger maintains cadence but fails to meet other performance standards (i.e., does not extend elbows fully on the rising, fails to bring the upper arms parallel to the ground on lowering, and sags/arches the pelvis/trunk at any point), the grader will repeat the number of the last correct repetition and tell the Ranger the proper correction.

Back to Top | Article Outline

Task 6: Heel Clap

The purpose of this test is to measure muscular strength and endurance of grip, pulling, and core muscles.

Back to Top | Article Outline

Task 6: Conditions

Given a pull-up bar that allows for full-body extension without the feet touching the ground, is long enough, and has enough space around it to perform the movement to standard.

Back to Top | Article Outline

Task 6: Standards

On the command “Ready,” Ranger moves to a free-hand position with elbows bent to approximately 90°, using an alternate grip, so that the body faces along the length of the pull-up bar. On the command “Go,” Ranger lifts his lower body upward and raises the feet over the bar to tap the heels together (repetitions will not be counted if only the toes touch over the bar). He returns to the starting position, maintaining the elbows at 90° throughout. He repeats this sequence as many times as possible. The body must be held approximately straight in the lower position. The Ranger cannot rest the legs on the bar or swing past the starting position on lowering. If Ranger extends the elbows to greater than 90°, that repetition does not count. The Ranger must return to and pause at 90° before attempting the next repetition. Ranger's score will be the number of correct repetitions performed.

Back to Top | Article Outline

Task 7: 300-Yard Shuttle Run

The purpose of this test is to measure anaerobic capacity.

Back to Top | Article Outline

Task 7: Conditions

Given a flat, athletic surface with line markings 25 yards apart.

Back to Top | Article Outline

Task 7: Standards

Line up in the sprint, crouch, or standup start positions with both feet and hands behind the starting line. The grader with give the preparatory command of “Ready.” On the command “Go,” Ranger runs to the opposite end of the course and makes a 180° turn by placing at least one foot on or over the line, returns to the starting line, makes another turn, and continues this way for 6 round trips, and sprint past the finish line on the last trip. Do not take a circular path to make any turn. The grader records the total time taken from the command “Go” to the completion of the course. A 2-minute rest period is given from when the last Ranger in the group crosses the finish line to the start of the second shuttle run. The grader records both scores, and the average score will determine the points given for this test. All times are measured to the nearest second that the grader has called out.

Back to Top | Article Outline

Task 8: Ranger Physical Assessment Test

The purpose of this test is to measure all components of fitness (strength, endurance, and movement skills) using tactically relevant tasks.

Back to Top | Article Outline

Task 8: Conditions

Given body armor, a helmet, and an obstacle course with a minimum of a 1-mile marked route, a 185lb SKEDCO, 20-foot fast rope apparatus, 20-foot caving ladder apparatus, and an 8-foot wall.

Back to Top | Article Outline

Task 8: Standards

Complete a 3-mile run and combat focused PT course in less than 40 minutes with all obstacles negotiated to standard. This event should be conducted as an individual assessment and with the mindset that the Ranger is competing against himself to put forth their best effort.

  • Subjects should conduct a 2-mile run wearing field uniform, boots, body armor, and a helmet.
  • After the completion of the run, they should climb the 20-foot fast rope and do a controlled descent.
  • Subjects should drag a 185-pound SKEDCO litter 50 yards, turn around, and drag back 50 yards to the start point.
  • Next, subjects should climb a 20-foot caving ladder and climb back down.
  • Then they should run 100 yards, turn around, and run 100 yards back.
  • And then they should scale an 8-foot wall.
  • Finally, subjects should conduct a 1-mile run wearing the previously listed uniform. Time stops when you cross the finish line.
Back to Top | Article Outline

Assessment of outcome

Pass or fail status for the RPAT was determined by completing the course in less than 40 minutes and successfully completing all obstacles to standard.

Back to Top | Article Outline

Assessment of covariates

Information from each event was examined for its relationship with passing the RPAT. The time for the agility shuttle was the average of 2 attempts; one attempt had the soldier start by going to the left and the other attempt had the soldier start to right. The broad jump was measured in inches. The maximum deadlift was calculated from a 3 repetition maximum, and relative deadlift was the calculated maximum in relation to the soldier's body mass. The 300-yard shuttle time was the average time in seconds from the 2 attempts in the event. The number of successfully completed heel claps, metronome-paced push-ups, and pull-ups was recorded.

Back to Top | Article Outline

Assessment of confounders

The age, height, and body mass of each soldier were recorded. Body mass index (BMI) was calculated as (mass/height2)*703. Age was split into 4 categories; 17–21, 22–26, 27–31, and ≥32 years old, based off of a modified version of the age categories used for the Army Physical Fitness Test (the categories for age 32 and older were collapsed into one category). Body mass index was categorized using guidance provided by the Centers for Disease Control. Because of low numbers of underweight candidates, the lower 2 categories were combined resulting in 3 BMI categories; <25, 25–29.9, ≥30 kg·m−2.

Back to Top | Article Outline

Statistical Analyses

Deadlift (3 repetition maximum), relative deadlift, and the agility shuttle average time were transformed from continuous variables to incremental variables to allow for easier detection of effect. The association between deadlift and RPAT score was examined for each 10-pound increase in the calculated maximum deadlift. The relative deadlift was examined based on increases of 5% body mass. The agility shuttle run average was examined using 1/4 second of increments in time. Where data may have been missing for individual soldiers, a Markov chain Monte Carlo method was used to multiply impute missing exposure and covariate data. We generated 5 imputation data sets using PROC MI and combined point estimates and standard errors from each data set using PROC MIANALYZE. Crude analyses were performed looking at each event variable separately in a logistic regression analyses to calculate an odds ratio (OR) for the initial relationships between each event and odds of passing the RPAT. Exposures that showed indication of an association with passing the RPAT, based off odds ratios significantly greater or less than 1, was then used in a combined logistic regression model. The resulting regression analysis was also adjusted for age and BMI. All statistical analyses were performed in SAS version 9.4.

Back to Top | Article Outline

Results

The mean age, height, body mass, and BMI for the soldiers in this study are shown in Table 1, along with the mean and range for all of the performance tests of soldiers who passed the RPAT and those who did not. The age, height, body mass, and BMI were similar in both the group who passed the RPAT and the group that did not pass. The mean and range for all the performance tests showed that the group who passed the RPAT performed better on all the tests in the physical assessment battery (Table 1). However, the mean scores were not largely different between the groups, and the ranges overlapped significantly for all of the tests. In the crude analysis, where each test was examined individually, better performance on each test was associated with better odds of passing the RPAT. Because tests were associated with improved odds of passing, they were all included in the overall logistic regression model, with adjustment for age and BMI.

Table 1

Table 1

The overall model provided point estimates suggesting that better performance on all the performance tests except for the 5-10-5 shuttle and metronome push-ups increased the odds of passing the RPAT (Table 2). The large confidence interval for the agility shuttle indicate a great deal of variability in the performance of this event independent of who passed the RPAT, and the point estimate near 1.0 and narrow confidence interval for the metronome push-ups suggested that performance on this test was not associated with better or worse odds of passing the RPAT. Better performance in the broad jump, pull-ups, and average 300-yard shuttle time were most associated with improved odds of passing the RPAT. For every increasing 2.54 centimeters in broad jump, the odds of passing the RPAT increased by 4% (OR = 1.04, 95% CI [1.01–1.07]). Each additional pull-up was associated with 6% better odds (OR = 1.06, 95% CI [1.01–1.12]) of passing the RPAT, and every second faster in the 300-yard shuttle was associated with 9% better odds of passing the RPAT (OR = 1.09, 95% CI [1.03–1.14]). The point estimates indicate that each repetition of heel claps and every 5% increase in relative deadlift might provide a slight improvement in the odds of passing the RPAT, but the confidence bounds dropping slightly below 1.00 making it difficult to state with definitive conclusion that there was relationship between better performance on these specific tests and improved odds of passing the RPAT.

Table 2

Table 2

Back to Top | Article Outline

Discussion

The strength and conditioning assessments used in the RAW program do have a significant relationship with the tactical assessment of RPAT performance. The results of this study indicate that the tasks assessing lower-body power, pulling strength, and anaerobic capacity seemed to have the greatest influence on RPAT success. Our finding that both strength and conditioning are key for a successful tactical assessment score are consistent with previous research by Kraemer et al. and Hendrickson et al., which demonstrated that resistance training with concurrent aerobic training is more beneficial to soldier performance than either alone (3,5). Although relative deadlift strength was not a strong indicator of RPAT success, recognizing the requirement of force to develop power and previous research demonstrating a correlation between lower-body strength and measures of speed and power (11), its importance should not be discounted but may not need to be an area of focus if current 3RM does not approach the mean for Rangers who passed the RPAT. The results of this study are also consistent with the recommendations of an expert panel of physiologists and military trainees who highlighted a need for a combination of resistance and conditioning training to optimize performance in tactically relevant military tasks (2).

When interpreting the results of this study, it is important to consider the entirety of the results and analyses. Better performance in each of the tests was associated with better performance on the RPAT when examined individually in a crude analysis. In the regression model comparing all the tests, better performance on the broad jump, pull-ups, and 300-yard shuttle showed statistical significance for improving the odds of passing the RPAT. This indicates that if the scores in all the other tests remained constant, an improvement in the broad jump, pull-ups, or 300-yard shuttle may improve the odds of passing the RPAT. Therefore, Rangers should not ignore or place less emphasis on the other tests. These results simply imply that these task scores may be to provide an area for specific training focus once a Ranger has met a level of performance in each of the tests that is consistent with physical performance scores shown by Rangers who pass the RPAT. As an example, if a Ranger is able to perform at a level in each test that is comparable with the higher end of the range of scores of Rangers who passed the RPAT, they may then choose to focus their efforts for further improvement on power, upper-body strength/endurance, and anaerobic capacity represented by the broad jump, pull-ups, and 300-yard shuttle, respectively. This analysis is lacking an aerobic measure such as a 20-m shuttle or 2-mile run; future research should involve an aerobic measure to determine how it might relate to a tactical assessment such as the RPAT.

The results of this study also provide information that can be used to develop or modify an Operator Readiness Assessment (ORA), such as the assessment described by Bear et al. (1). The 75th Ranger Regiment Human Performance and Sports Medicine staff currently use the RAW Assessments and the RPAT as part of a comprehensive return to duty assessment for injured Rangers. The current model uses the Ranger's previous performance scores, with the goal of achieving a minimum of 90% of their previous score before being cleared to return to duty. Human Performance and Sports Medicine Staff may be able to adapt and use the results of this study as objective measures to determine return to duty for RASP I candidates who have suffered an injury but have no previous assessment data. Other Army units outside USASOC are also using components of the RAW assessments and the RPAT as Human Performance measurements and may benefit from using our key assessment numbers for training and return to duty status as well.

Back to Top | Article Outline

Practical Applications

Our current results provide guidance to Strength Coaches and Tactical Strength and Conditioning Facilitators (TSAC-Fs) preparing their tactical athletes for this specific or similar tactical assessment in terms of focus areas of lower-body power, pulling strength, and anaerobic endurance as keys to success. For units without Strength Coaches or TSAC-Fs, unit training personnel can use guidelines provided in Strength Training for the Warfighter by Kraemer and Szivak (4) and provided focus areas to design a safe and effective program. We also demonstrated that given the significance of the athletic based assessments in a tactical assessment, Strength Coaches and TSAC-Fs can play a key role in preparing tactical athletes for their job requirements. Finally, we provided much needed normative data on soldiers attempting RASP I and who were successful on the RPAT as a metric for other soldiers to train for and compare against or to be used in a Readiness Assessment in injured soldiers to determine when they are ready to return to duty. As stated by Bradley Warr et al. (10) in regards to the tactical athlete, “fitness testing is a valuable tool for assessing the health status, health-related risk factors, job readiness, and suitability”.

Back to Top | Article Outline

Acknowledgments

The authors would acknowledge the USASOC and 75th Ranger Regiment leadership and staff who supported this project specifically RAW and THOR3 personnel who assisted with data collection. No external funding used for this project.

The investigators adhered to the policies for protection of human subjects as prescribed in Army Regulation 70-25, and the research was conducted in adherence with the provisions of 32 CFR part 219. The opinions or assertions contained herein are the private views of the authors and are not to be construed as official or as reflecting the views of the Army or the Department of Defense. Any citations of commercial organizations and trade names in this report do not constitute an official Department of the Army endorsement of approval of the products or services of these organizations.

Back to Top | Article Outline

References

1. Bear R, Sanders M, Pompili J, Stucky L, Walters A, Simmons J, et al. Development of the tactical human optimization, rapid rehabilitation, and reconditioning program military operator readiness assessment for the special forces operator. Strength Cond J 38: 55–60, 2016.
2. Friedl KE, Knapik JJ, Häkkinen K, Baumgartner N, Groeller H, Taylor NA, et al. Perspectives on aerobic and strength influences on military physical readiness: Report of an international military physiology roundtable. J Strength Cond Res 29: S10–S23, 2015.
3. Hendrickson NR, Sharp MA, Alemany JA, Walker LA, Harman EA, Spiering BA, et al. Combined resistance and endurance training improves physical capacity and performance on tactical occupational tasks. Eur J Appl Physiol 109: 1197–1208, 2010.
4. Kraemer WJ, Szivak TK. Strength training for the warfighter. J Strength Cond Res 26: S107–S118, 2012.
5. Kraemer WJ, Vescovi JD, Volek JS, Nindl BC, Newton RU, Patton JF, et al. Effects of concurrent resistance and aerobic training on load-bearing performance and the army physical fitness test. Mil Med 169: 994–999, 2004.
6. Mala J, Szivak TK, Flanagan SD, Comstock BA, Laferrier JZ, Maresh CM, et al. The Role of Strength and Power during Performance of High Intensity Military Tasks under Heavy Load Carriage. US Army Med Dept Jrnl, 2015.
7. McMillian D. Ranger-athlete-warrior: A systematic approach to conditioning. Infantry 96: 58, 2007.
    8. 75th Ranger Regiment. RAW Assessments Tasks, Conditions, and Standards. Fort Benning, Georgia: 75th Ranger Regiment, 2016.
    9. Scofield DE, Kardouni JR. The tactical athlete: A product of 21st century strength and conditioning. Strength Cond J 37: 2–7, 2015.
    10. Warr, B PG, Scofield D, Jaenen S. Testing and evaluation of tactical populations. In: NSCA's Essentials of Tactical Strength and Conditioning KS Brent Alvar, Patricia Deuster. Champaign, IL: Human Kinetics, 2017, pp. 136–148.
    11. Wisløff U, Castagna C, Helgerud J, Jones R, Hoff J. Strong correlation of maximal squat strength with sprint performance and vertical jump height in elite soccer players. Br J Sports Med 38: 285–288, 2004.
    Keywords:

    special operations; human performance; tactical athletes

    Supplemental Digital Content

    Back to Top | Article Outline
    Copyright © 2019 by the National Strength & Conditioning Association.