Physical Conditioning for Initial Military Training CPT Paul C. Henning, Ph.D., CSCS Research Physiologist, Military Performance Division U.S. Army Research Institute of Environmental Medicine Natick, MA Basic military training Overview Problems associated with basic military training Risk factors for training-related injuries Civilian and military fitness trends Physical fitness screening Practical guidelines for recruits 1
Initial Military Training Initial Military Training (IMT) also known as basic combat training, basic training, boot camp Army: 10 weeks Navy: 8 weeks Air Force: 8 ½ weeks Marines: 13 weeks Initial Military Training Fundamentals of soldieringspanning warrior tasks, physical training, combative tactics, and military customs and courtesies. Daily schedules are highly structured and are physically stressful Physical aspects of U.S. Army basic combat training by phase (Henning 2011, SCJ) Component of BCT Phase I Phase II Phase III Physical Aspects Daily physical readiness training (PRT) (running, calisthenics) Marching drills Combat skills Bayonet training Personnel carrying methods Daily physical readiness training [PRT) (running, calisthenics) Tactical foot march Engagement skills Situational training exercises (STX) Daily physical readiness training (PRT) (running, calisthenics) 10km and 15km foot marches Field training exercises (FTX) Army Physical Fitness Test (APFT) 2 minutes of sit-ups 2 minutes of push-ups 2 mile timed run 2
Problems associated with IMT IMT related musculoskeletal injuries significantly impact Department of the Army. Evident in other countries (Israel, Finland, Australia) - ~25% male and 50% female recruits sustain one or more injuries during basic combat training (BCT) (Technical Bulletin Medical 592, U.S. Army) Problems associated with IMT Cost during FY 2005 estimated at $57,500 per discharged recruit. (Niebuhr, 2008) National Research Council Committee on the Youth Population and Military Recruitment highlighted entry-level training-related injuries as the single most significant medical impediment to military readiness. Overuse injuries account for 70 to 80% of IMTrelated musculoskeletal injuries and thus more than half of all disability discharges among firstyear recruits (Niebuhr, 2006) 35 % of injuries in males & females 30 25 20 15 10 5 * Females Males 0 Stress fractures Anterior knee pain Achilles tendonitis Back pain Ankle sprain * p<0.05, significantly greater than males 3
Physical Fitness and Training-Related Injury Risk Researchers identified multiple risk factors for training-related injury with physical fitness being a prominent risk factor. Molloy et al 2012 Physical Fitness and Training-Related Injury Risk Each fitness component impacts risk to a varying degree Low aerobic fitness most strongly and consistently associated with increased injury risk (Jones & Knapik, 1991; Rauh et al 2006) Low aerobic fitness and low muscular endurance are risk factors for injuries in other countries, including Australia, Norway, England, and Israel (Pope et al 1999; Heir 1997; Rayson 2003) 4
Physical Fitness and Training-Related Injury Risk Strength asymmetries (left to right side differences) associated with increased risk (Kiesel et al 2007) Low BMI lesser muscle or bone mass, underweight recruits may lack strength required for strenuous tasks (e.g. load carriage) (Blacker et al 2008) Civilian and Military Fitness Trends Today s youth appear less prepared for entry-level training than their predecessors given close relationship between timed running performance and IMT aerobic fitness requirements (Molloy et al 2012) Report shows low aerobic fitness levels among 1/3 of American youths aged 12-19 (Pate et al 2006) Civilian and Military Fitness Trends Physical fitness of young men in Norwegian, Finnish, and Swill Armies decreased over last 20 years (Dyrstad et al. 2005; Santtila, et al. 2006; Wyss, et al. 2009) Steadily increasing failure rates on Army s 1-1-1 physical assessment test suggest decline in recruit fitness (2003-2009) 5
Civilian and Military Fitness Trends Civilian and Military Fitness Trends Civilian and Military Fitness Trends CDC reported an increase in obesity (defined as BMI > 30) among Americans across past 2 decades. Excessive weight/body fat remains primary reason for recruit medical disqualifications (Accession Medical Standards Analysis & Research Activity, 2010) 6
Physical Fitness Screening Only Marines and Navy screen recruits preenlistment fitness levels. PCH1 Marine recruits must pass standardized Initial Strength Test (IST) before proceeding to basic training Physical Fitness Screening Physical Fitness Screening Recruits must again pass IST upon arrival at basic training. IST failures assigned to Physical Conditioning Platoon (PCP) to improve fitness before beginning basic training. 7
Slide 19 PCH1 see if can get data on attrition/injuries in Marine basic Paul Clifford Henning, 1/11/2013
Physical Fitness Screening 1999 Army s TRADOC administered 1-1-1 test to all recruits before beginning IMT. Recruits that failed assigned to Fitness Training Unit (FTU). Recruits remained within FTU until passing the 1-1-1 test and progressing to BCT. FTU reduced injury risk and attrition, this enabling Army to retain ~516 recruits and save over $14 million annually in early 2000s (Knapik et al 2004, Knapik et al 2006) Physical Fitness Screening Army eventually discontinued 1-1-1- testing and automatic assignment to FTU. Currently, FTU assignment limited to recruits who repeatedly fail the APFT despite completing all other BCT requirements As of July 2011, ~93% of recruits in FTU at Fort Jackson achieved BCT standards for APFT (50 points per event) after performing Physical Readiness Training (PRT) for 2-4 weeks (M. Reed, personal communication, 2011 Physical Fitness Screening Army conducted an Assessment of Recruit Motivation and Strength (ARMS) (2005-2009). Consisted of modified Harvard step test and 1-minute push-up test Attrition rates significantly higher among ARMS failures (Niebuhr et al 2008). Recruits who passes ARMS test received body composition enlistment waivers. Increased risk of injury but not attrition (Cowan et al 2011) 8
Physical Fitness Screening RAND reported ARMS program accessed an additional 3690 recruits in FY 2007 at an estimated per-recruit cost of $163 (Loughran and Orvis) Army discontinued ARMS testing in September 2009 due to improved recruiting environment. Physical Fitness assessment Australian Defence Force Summary of studies on basic training Inadequate preparatory physical conditioning results in poor fitness test performance and increased risk of musculoskeletal injuries, thus contributing to attrition rates in basic training 9
Practical guidelines for recruits Medical attrition rates of 4 cohorts of recruits undergoing basic military training (BMT) Group A (n=3475)-mixture of fit and unfit recruits Trained under standard combat BMT program Group B (n=2081)-only fit recruits Passed pre-bmt fitness minimum criteria Group C (n=940)-unfit recruits Underwent pre-training conditioning program from 4-6 weeks prior to a similar 3-month BMT Group D (n=2613)-unfit recruits Underwent extended 4-month BMT which allowed more gradual pace 10
A formal pre-training conditioning program resulted in lower attrition during BMT and this reduction was more effective than training the recruits at a slower pace by extending the BMT by one month Three groups of recruits at Fort Jackson, SC PC : failed entry level PT test and entered FTU. Trained until pass test and entered BCT. NPC: failed entry level PT test; allowed to enter BCT without preconditioning in FTU NNPC: passed the entry level PT test and went directly to BCT 11
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The proportions of NPC, PC, and NNPC recruits who completed the 9-week BCT cycle were 59%, 83%, and 87% for men (p < 0.01) and 52%, 69%, and 78% for women (p < 0.01) respectively. Compared with NNPC men, injury risk was 1.5 and 1.7 times higher for PC and NPC men, respectively. Compared with NNPC women, injury risk was 1.2 and 1.5 times higher for PC and NPC women, respectively. Conclusion: Low-fit recruits who are preconditioned have reduced BCT attrition and tend to have lower injury risks compared with low-fit recruits who do not precondition. 13
Program design for potential recruits Physical fitness ability to perform sustained physical work characterized by an effective integration of cardiorespiratory endurance, strength, flexibility, coordination, and body composition (Miller et al. 1991) Program design for potential recruits ACSM well-rounded training program should include aerobic and strength training for the major muscle groups. Frequency of 3-5 and 2-3 training sessions per week recommended for improving aerobic fitness and muscular strength, respectively. When recommendations met, improvements in task performance in military settings have been observed in as little as 4-8 weeks (Frykman et al. 2006; Harman et al. 2006; Sharp et al 2006) Effects of Concurrent Resistance and Aerobic Training on Load- Bearing Performance and the Army Physical Fitness Test (Kraemer et al. 2004) Purpose - Examine how concurrent RT and ET would impact a loaded 2-mile run in male Army personnel. Subjects 35 active duty men (ages 18-29) 4 training groups: 1) RT + ET, 2) UB + ET, 3) RT only, 4) ET only Training 12 weeks, 4 sessions/week (Mon, Tues, Thurs, Fri) Resistance training program varied workouts within each week (i.e,. nonlinear periodization) designed to enhance muscle hypertrophy and strength. Endurance training program Long distance runs (Mondays and Thursdays) Sprint intervals (Tuesdays and Fridays) Load Carriage Tasks A maximal effort 2-mile loaded run (44.7 kg = 98lbs) Performance measure Time to complete 14
Hypertrophy Training Regimen (Mon & Thurs) Body Area Sets RM Rest (mins) Bench press + flys 3 10 1 Shoulder press + upright row Lat pulldown + seated row 2 10 1 3 10 1 Bicep curls 3 10 1 Leg ext + Leg 3 10 1 curl Split squats 3 10 1 Calf raises 3 15 1 Sit-ups 2 25 1 Strength Training Regimen (Tues & Fri) Body Area Sets RM Rest (mins) Bench Press 5 5 2-3 Shoulder Press Bicep curls Lat pulldown 5 5 2-3 5 5 2-3 5 5 2-3 Dead lift 4 6 2-3 Leg press 5 5 2-3 Leg extension 5 5 2-3 Calf raises 3 10 2-3 Obliques 5 10 Sit-ups 5 10 Combined resistance and endurance training improves physical capacity and performance on tactical occupational tasks (Hendrickson et al. 2010) Purpose evaluate the effectiveness of endurance, strength, and the additive effect of strength and endurance training for improving the performance of common tactical occupational tasks among recreationally active women Subjects 56 recreationally active women, 18 26 years old Groups Combined (n=15) Resistance (n=18) Endurance (n=13) Control (n=10) Training 12 weeks, 3 sessions/week (Mon, Wed, Fri) Load Carriage Tasks A maximal effort 2-mile loaded run (32.7 kg = 72lbs) Performance measure Time to complete Program variables for the endurance exercise training program (Hendrickson et al. 2010) Week Monday (easy SS, longer) Wed (interval and TT) Fri (SS, threshold) 1 Pre-testing & familiarization 2 Pre-testing & familiarization (3.2 km TT) 3 20-30 min SS or jog/walk (100 m jog/100 m walk) 20-30 min SS 20-30 min SS 4 30 min total SS,75% HR max 30 min total (1.6 km alternating straights fast, jog/walk corners) 30 min SS, 80-85% HR max 5 30 min total SS, 75% HR max 1 x 800m, 1 x 400m, 2 x 30 min SS, 80-85% HR 200m) max 6 30 min total SS, 75% HR max 3 x 800 m) 30 min SS, 80-85% HR max 7 Mid testing 8 30 min total SS, 75% HR max (8 x 400 m ) 30 min SS, 80-85% HR max 9 30 min total SS, 75% HR max (1 x 1.6 km, 1 x 800m, 2 30 min SS, 80-85% HR x 400m) max 10 30 min total SS, 75% HR max 2 x 1.6km (5 min rest in 30 min SS, 80-85% HR between) max 11 30 min total SS, 75% HR max 4.8km SS 3.2km TT 12 Post-testing 15
Program variables within periodized resistance training program (Hendrickson et al. 2010) Weeks 1-2 Acute program variables Light Moderate Heavy Pre-testing & familiarization Weeks 3-6 Sets 3 3 3 Reps 12 8-10 6-7 Rest (s) 90 120 120 Total time (min) 40 48 47 Week 7 Mid-testing Weeks 8-11 Sets 3 3 3 Reps 12 6-8 3-5 Rest (s) 90 150 180 Total time (min) 40 57 63 Week 12 Post-testing Resistance Exercises (Hendrickson et al. 2010) Monday Wednesday Friday Exercises Squat Leg press Squat Stiff-leg deadlift Stiff-leg deadlift Stiff-leg deadlift Bench press Lat pull down Upright row Calf exercises Abdominal work Incline bench press Seated row Shoulder press Calf exercises Abdominal work Bench Lat pull down Upright row Calf exercises Abdominal work Preparatory 12-week strength training (ST) and endurance training (ET) guidelines for Basic Combat Training (Henning, 2011) Mesocycle Week ST Prescription ET Prescription - 1 1 2-5 Familiarization period; Establish initial training loads Frequency Frequency 2x/week 2x/week Sets/Reps/Rest Mode/Intensity/Duration Day 1: 3x12RM, 90s Day 1: LSD, 70-75% Day 2: 3x8-10RM, 120s APMHR, 20-30 min Day 2: Intervals (4 x 100m, 2 x 200m) - 6 Active recovery; Adjust loading as needed for next mesocycle 16
Preparatory 12-week strength training (ST) and endurance training (ET) guidelines for Basic Combat Training (Henning, 2011) Mesocycle Week ST Prescription ET Prescription Frequency 3x/week Sets/Reps/Rest Day 1: 3x12RM, 90s Frequency 3x/week Mode/Intensity/Duration Day 1: Intervals (4 x 400 2 7-10 Day 2: 3x8-10RM, 120s m)* Day 3: 3x6-7RM, 150- Day 2: LSD, 75-80% 180s APMHR, 20-30 min Day 3: Intervals (4 x 200m, 4 x 400m, 2 x 800m) - 11 Active recovery; Adjust loading as needed for next mesocycle *Perform 5-kilometer unloaded marching twice per mesocycle instead of prescribed activity. Preparatory 12-week strength training (ST) and endurance training (ET) guidelines for Basic Combat Training (Henning, 2011) Mesocycle Week ST Prescription ET Prescription Frequency 3x/week Sets/Reps/Rest Day 1: 3x12RM, 90s Day 2: 3x6-8RM, 150s Frequency 3x/week Mode/Intensity/Duration Day 1: Intervals (6 x 400m)^ 3 12-15 Day 3: 3x4-5RM, 180s Day 2: LSD, 80-85% APMHR, 20-30 min Day 3: Intervals (6 x 200m, 6 x 400m, 4 x 800m) - 16 Rest and recovery prior to Basic Combat Training ^Perform 5-kilometer marching with standard load (15.87kg) twice per mesocycle instead of prescribed activity. Sample strength and endurance exercises for mesocycle 2 of pre-basic Combat Training conditioning program (Henning, 2011) Strength Exercises Day 1 High Pull Squat Bench Press Lat Pull Down Shoulder Press Incline Sit-ups (20-30 reps) Leg raises (20-30 reps) Endurance Exercises Day 1 Interval training Can be performed on track at various distances: Sprint straights, walk corners 4 x 400m (assignments depending on training status of individual) Performed at maximal to near-maximal intensity 1:2 work to rest ratio, decrease rest as tolerated Twice during mesocycle, perform 5-kilometer unloaded marching instead 17
Sample strength and endurance exercises for mesocycle 2 of pre-basic Combat Training conditioning program (Henning, 2011) Strength Exercises Day 2 Push Press Leg Press Straight Leg Deadlift Incline Dumbbell Press Barbell Row Upright Row Sit-ups (with holding the feet down) (20-30 reps) Leg raises (20-30 reps) Endurance Exercises Day 2 Long-Slow Distance (LSD) Intensity: 75-80% APMHR, Duration: 20-30 min Sample strength and endurance exercises for mesocycle 2 of pre-basic Combat Training conditioning program (Henning, 2011) Strength Exercises Day 3 High Pull Squat Straight Leg Deadlift Flat Dumbbell Press Barbell Row Shoulder Press Incline Sit-ups (20-30 reps) Leg raises (20-30 reps) Endurance Exercises Day 3 Interval training Can be performed on track at various distances: Sprint straights, walk corners 4 x 200m, 4 x 400m, 2 x 800m (assignments depending on training status of individual) Performed at maximal to near-maximal intensity 1:2 work to rest ratio, decrease rest as tolerated Recommended Interventions (Molloy et al 2012 Basic training is an expensive screening function NRC recommends pre-accession testing for all services Resume 1-1-1 testing at recruiting stations for all recruits and ARMS testing at MEPS for recruits exceeding body composition accession standards. Meeting minimum pre-enlistment fitness standards could screen out individuals who fail to respond or lack motivation to adhere to an exercise program. Screening could positively influence injury and attrition rates A pre-imt fitness program and standardized fitness guide address this need (Rieger & Scott, 2006) 18
Conclusion and summary Training-related injuries negatively impact the military services Low (particularly aerobic) fitness levels among recruits associated with increased risk for injury and attrition. Recommend that pre-enlistment fitness screening be conducted whenever possible would likely decrease attrition and injuries. Preparatory physical conditioning program conducted by recruits has been research-proven to attenuate attrition and injuries during IMT. Disclaimer The views, opinions, and/or findings contained in this presentation are those of the author and should not be construed as an official Department of the Army position, policy, or decision unless so designated by other documentation. CPT Paul C. Henning U.S. Army Research Institute of Environmental Medicine Kansas Street, Bldg 42 Natick, MA 01760 paul.c.henning@us.army.mil Suggested Readings Technical Bulletin Medical 592. U.S. Department of the Army, Prevention and control of musculoskeletal injuries associated with physical training. Washington, DC, 2011. Available at http://armypubs.army.mil/med/dr_pubs/dr_a/pdf/tbmed592.pdf; accessed January 12, 2012. Niebuhr DW, Scott CT, Powers TE, et al: Assessment of recruit motivation and strength study: preaccession physical fitness assessment predicts early attrition. Mil Med 2008; 173(6): 555 62 National Research Council. Physical fitness and musculoskeletal injury. In: Assessing Fitness for Military Enlistment: Physical, Medical, and Mental Health Standards, pp 66 108. Edited by Sackett PR, Mavor AS. Washington, DC, National Academies Press, 2006. 19
Suggested Readings Almeida SA, Williams KM, Shaffer RA, Brodine SK: Epidemiological patterns of musculoskeletal injuries and physical training. Med Sci Sports Exerc 1999; 31(8): 1176 82. Jones BH, Shaffer RA, Snedecor MR: Chapter 6. Injuries treated in outpatient clinics: surveys and research data. Mil Med 1999; 164(8 Suppl): 1 89. Kiesel K, Plisky PJ, Voight ML: Can serious injury in professional football be predicted by a preseason functional movement screen? N Am J Sports Phys Ther 2007; 2(3): 147 58. Jones BH, Darakjy S, Knapik JJ: Aerobic fitness, body mass index and risk of injury during Army Basic Combat Training. Med Sci Exer 2004; 36(5): S308. Blacker SD, Wilkinson DM, Bilzon JL, Rayson MP: Risk factors for training injuries among British Army recruits. Mil Med 2008; 173(3): 278 86. Suggested Readings Pate RR, Wang CY, Dowda M, Farrell SW, O Neill JR: Cardiorespiratory fitness levels among US youth 12 to 19 years of age: findings from the 1999 2002 national health and nutrition examination survey. Arch Pediatr Adolesc Med. 2006; 160(10): 1005 12. Knapik JJ, Darakjy S, Hauret KG, et al: Increasing the physical fitness of low-fit recruits before basic combat training: an evaluation of fitness, injuries, and training outcomes. Mil Med 2006; 171(1): 45 54. National Research Council. Physical fitness and musculoskeletal injury. In: Assessing Fitness for Military Enlistment: Physical, Medical, and Mental Health Standards, pp 66 108. Edited by Sackett PR, Mavor AS. Washington, DC, National Academies Press, 2006 20