Tibial stress changes in new combat recruits for special forces: patterns and timing at MR imaging.

Purpose: To characterize the incidence, location, grade, and patterns of magnetic resonance (MR) imaging findings in the tibia in asymptomatic recruits before and after 4-month basic training and to investigate whether MR imaging parameters correlated with pretraining activity levels or with future symptomatic injury.

Materials And Methods: This study was approved by three institutional review boards and was conducted in compliance with HIPAA requirements. Volunteers were included in the study after they signed informed consent forms.

Bone turnover markers do not predict stress fracture in elite combat recruits.

Background: With bone resorption rates greater than formation, stress fracture pathogenesis plausibly involves bone remodeling imbalance. If this is the case, one would anticipate serum levels of bone turnover markers would be higher in patients with stress fractures than in those without.

Questions/purposes: We therefore asked whether: (1) bone turnover markers differ between soldiers who will or will not have stress fractures during basic training; (2) bone turnover markers change during basic training; and (3) serial bone formation or bone resorption markers differ between subjects with and without stress fractures during basic training?

Methods: We performed serial determinations of serum bone formation (bone alkaline phosphatase [BAP] and procollagen type I amino-terminal propeptide [PINP]), and resorption (tartrate-resistant acid phosphatase [TRAP5b] and cross-linked collagen telopeptide [CTx]) biomarkers, measured at 2- to 4-week intervals (during 18 weeks) in 69 male soldiers in the Israeli Defense Forces during elite basic training.

A multiple intervention strategy for reducing femoral neck stress injuries and other serious overuse injuries in U.S. Army Basic Combat Training.

We hypothesized that the use of evidence based injury prevention strategies would lead to a reduction in the incidence of femoral neck stress injuries (FNSIs) and other serious overuse injuries in U.S. Army Basic Combat Training (BCT).

IGF-I, IGFBPs, and inflammatory cytokine responses during gender-integrated Israeli Army basic combat training.

Insulin-like growth factor 1 (IGF-I) is a robust metabolic and anabolic biomarker that has been demonstrated to be reflective of military training-induced body composition changes and influenced by initial aerobic fitness level. Greater mechanistic insight into the IGF-I response to physical training can potentially be gleaned by also examining other regulatory factors that influence IGF-I biological activity (i.e.

Dietary intake and stress fractures among elite male combat recruits.

Background: Appropriate and sufficient dietary intake is one of the main requirements for maintaining fitness and health. Inadequate energy intake may have a negative impact on physical performance which may result in injuries among physically active populations. The purpose of this research was to evaluate a possible relationship between dietary intake and stress fracture occurrence among combat recruits during basic training (BT).

Anemia, iron deficiency, and stress fractures in female combatants during 16 months.

Yanovich, R, Merkel, D, Israeli, E, Evans, RK, Erlich, T, and Moran, DS. Anemia, iron deficiency, and stress fractures in female combatants during 16 months. J Strength Cond Res 25(12): 3412-3421, 2011-The purpose of this study is to evaluate the hematological profile of military recruits in different settings and training programs and to investigate the link between anemia and iron deficiency with stress fracture (SF) occurrence.

Prediction model for attrition from a combat unit training program.

The purpose of this study was to develop a prediction model for the attrition rate of soldiers from an 8-month advanced military training program based on physical and psychological factors. Two groups of 59 and 61 healthy, fit young men (18.7 ± 0.

Biological constraints that limit compensation of a common skeletal trait variant lead to inequivalence of tibial function among healthy young adults.

Having a better understanding of how complex systems like bone compensate for the natural variation in bone width to establish mechanical function will benefit efforts to identify traits contributing to fracture risk. Using a collection of pQCT images of the tibial diaphysis from 696 young adult women and men, we tested the hypothesis that bone cells cannot surmount the nonlinear relationship between bone width and whole bone stiffness to establish functional equivalence across a healthy population. Intrinsic cellular constraints limited the degree of compensation, leading to functional inequivalence relative to robustness, with slender tibias being as much as two to three times less stiff relative to body size compared with robust tibias.

Clinical utility of tibial motor and sensory nerve conduction studies with motor recording from the flexor hallucis brevis: a methodological and reliability study.

Background: Standard tibial motor nerve conduction measures are established with recording from the abductor hallucis. This technique is often technically challenging and clinicians have difficulty interpreting the information particularly in the short segment needed to assess focal tibial nerve entrapment at the medial ankle as occurs in posterior tarsal tunnel syndrome. The flexor hallucis brevis (FHB) has been described as an alternative site for recording tibial nerve function in those with posterior tarsal tunnel syndrome.

Effects of a prolonged submersion on bone strength and metabolism in young healthy submariners.

Submariners taking part in prolonged missions are exposed to environmental factors that may adversely affect bone health. Among these, relatively high levels of CO(2), lack of sunlight exposure affecting vitamin D metabolism, limited physical activity, and altered dietary habits. The aims of this study were to examine the effect of a prolonged submersion (30 days) on changes in bone strength using quantitative bone speed of sound and in markers of bone metabolism that include bone turnover (BAP, PINP, TRAP5b, and CTx) and endocrine regulators (serum calcium, PTH, and 25[OH]D) in a group of 32 young healthy male submariners.

Influence of exercise mode and osteogenic index on bone biomarker responses during short-term physical training.

Prescribing exercise based on intensity, frequency, and duration of loading may maximize osteogenic responses in bone, but a model of the osteogenic potential of exercise has not been established in humans. In rodents, an osteogenic index (OI) has been used to predict the osteogenic potential of exercise. The current study sought to determine whether aerobic, resistance, or combined aerobic and resistance exercise programs conducted over eight weeks and compared to a control group could produce changes in biochemical markers of bone turnover indicative of bone formation.

Stress fracture and military medical readiness: bridging basic and applied research.

Purpose: Military recruits and distance runners share a special risk of stress fracture injury. Recent efforts by US and Israeli military-sponsored researchers have uncovered important mechanisms and practical low-cost interventions. This article summarizes key findings relevant to prevention of stress fracture, including simple strategies to identify and to mitigate risk.

Prediction model for stress fracture in young female recruits during basic training.

Purpose: To develop a new prediction model for stress fractures (SF) in female recruits during basic training (BT) to identify risk factors and to try to prevent orthopedic injuries.

Methods: Measurements and data collection were taken from three companies of gender-integrated recruited units before the BT program (a total of 227 females and 83 males). Measurements included anthropometric variables, blood samples for hematology profile and markers for bone metabolism, fitness tests, bone quality (peripheral quantitative computed tomography), nutritional and activity habits, psychological assessment, and medical evaluation.

Sex differences in parameters of bone strength in new recruits: beyond bone density.

Background: Stress fracture (SF) injuries in new recruits have long been attributed to low bone mineral density (BMD). Low areal BMD assessed using two-dimensional dual-energy x-ray absorptiometry imaging, however, reflects structural density and is affected by smaller measures of bone geometry. Recent studies support a relationship between bone size and SF and indicate that slender bones are more susceptible to damage under identical loading conditions.

Effects of a 4-month recruit training program on markers of bone metabolism.

Unlabelled: Stress fracture susceptibility results from accelerated bone remodeling after onset of novel exercise and may be reflected in bone turnover changes. It is unknown if the bone turnover response to exercise is different between sexes.

Purpose: To assess disparity between sexes in bone metabolism markers during military recruit training and to evaluate relationships between bone turnover markers and factors that may affect bone metabolism.

Iron deficiency and the role of nutrition among female military recruits.

Unlabelled: The impact of iron deficiency is considerable when enhanced physical fitness is required. Female military recruits represent a unique population faced with intense physical and cognitive demands.

Purpose: To examine the prevalence of iron deficiency and the impact of dietary habits among female recruits in the Israel Defense Forces.

The association between hematological and inflammatory factors and stress fractures among female military recruits.

Background: With the growing number of females accepted for combat-related military duties in the Israeli Defense Forces, their special needs should be addressed. Previous studies on females in combat training have found a high prevalence of iron deficiency at recruitment as well as an increased rate of stress fractures (SF) and overuse injuries during training when compared with males. The aim of this study was to assess the correlation between hematological and inflammatory variables and SF occurrence among military recruits during basic training.

Motivation, cohesion, satisfaction, and their relation to stress fracture among female military recruits.

The purpose of this study was to compare ratings of motivation, satisfaction, self-efficacy, and cohesion between male and female soldiers undergoing basic training (BT) in a gender-integrated unit and to study whether the ratings differ in a subgroup of women who suffered stress fractures (SF) during the course of training. Data were collected from 3 different companies of an integrated combat unit using questionnaires that were completed by 41 male and 160 female soldiers (age 18.5 +/- 0.

Imaging of lower extremity stress fracture injuries.

Stress reactions and stress fractures in the lower extremities occur frequently in military and athletic populations. As the clinical symptoms of stress fracture may mimic other less severe musculoskeletal injuries, the diagnosis of stress fracture can often be delayed. The following article reviews the characteristics, advantages and disadvantages of the various imaging tools available to detect stress fracture of the lower limbs in order to clarify their utility when diagnosing this condition.

Upper body fatiguing exercise and shooting performance.

This study assessed the effect of upper extremity muscle fatigue on shooting performance while in a standing, unsupported firing position. Nine male and three female soldiers fired at targets before and after performing upper extremity exercise to fatigue using both (1) an upper body ergometer and (2) a Military Operations in Urban Terrain obstacle course. Shooting accuracy, assessed by the number of hits, misses, and shot group size, was significantly decreased (p < 0.

Effects of warm-up before eccentric exercise on indirect markers of muscle damage.

Purpose: To test whether active and passive warm-up conducted before eccentric exercise attenuates clinical markers of muscle damage.

Methods: Untrained subjects were exposed to one of five conditions: low-heat passive warm-up (N = 10), high-heat passive warm-up (N = 4), or active warm-up (N = 9), preceding eccentric exercise; eccentric exercise without warm-up (N = 10); or high-heat passive warm-up without eccentric exercise (N = 10). Passive warm-up of the elbow flexors was achieved using pulsed short-wave diathermy, and active warm-up was achieved by concentric contraction.