This study reviews historical and biomedical aspects of soldier load carriage. Before the 18th century, foot soldiers seldom carried more than 15 kg while on the march, but loads have progressively risen since then. This load increase is presumably due to the weight of weapons and equipment that incorporate new technologies to increase protection, firepower, communications, and mobility. Research shows that locating the load center of mass as close as possible to the body center of mass results in the lowest energy cost and tends to keep the body in an upright position similar to unloaded walking. Loads carried on other parts of the body result in higher energy expenditures: each kilogram added to the foot increases energy expenditure 7% to 10%; each kilogram added to the thigh increases energy expenditure 4%. Hip belts on rucksacks should be used whenever possible as they reduce pressure on the shoulders and increase comfort. Low or mid-back load placement might be preferable on uneven terrain but high load placement may be best for even terrain. In some tactical situations, combat load carts can be used, and these can considerably reduce energy expenditure and improve performance. Physical training that includes aerobic exercise, resistance training targeted at specific muscle groups, and regular road marching can considerably improve road marching speed and efficiency. The energy cost of walking with backpack loads increases progressively with increases in weight carried, body mass, walking speed, or grade; type of terrain also influences energy cost. Predictive equations have been developed, but these may not be accurate for prolonged load carriage. Common injuries associated with prolonged load carriage include foot blisters, stress fractures, back strains, metatarsalgia, rucksack palsy, and knee pain. Load carriage can be facilitated by lightening loads, improving load distribution, optimizing load-carriage equipment, and taking preventive action to reduce the incidence of injury.

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Soldier Load Carriage: Historical, Physiological, Biomechanical, and Medical Aspects

Load carriage using packs: a review of physiological, biomechanical and medical aspects

Chronic groin pain in athletes is often difficult to diagnose and treat. There are many anatomic structures in the inguinal and groin region that have the potential to cause pain. We report 32 cases of a previously undescribed condition in athletes of "obturator neuropathy," a fascial entrapment of the obturator nerve where it enters the thigh. This condition represents a type of groin pain in athletes that is treatable by surgical means. There is a characteristic clinical pattern of exercise-induced medial thigh pain commencing in the region of the adductor muscle origin and radiating distally along the medial thigh. Needle electromyography demonstrates denervation of the adductor muscles. Surgical neurolysis treatment provides the definitive cure of this problem, with athletes returning to competition within several weeks of treatment. The surgical findings are entrapment of the obturator nerve by a thick fascia overlying the short adductor muscle. The role of conservative treatment in the management of this condition is unknown at present.

/pdf/obturator-nerve-entrapment-a-cause-of-groin-pain-in-athletes-agyljwpkh5.pdf

Obturator Nerve Entrapment A Cause of Groin Pain in Athletes

https://www.sportsmed.theclinics.com/article/S0278-5919(06)00046-9/pdf

Sports-related muscle injury in the lower extremity.

Objective: To identify characteristics and factors associated with increased risk for stress fractures in military women.Design: Case-control study to retrospectively examine physical activity, prior calcium intake, and bone density as predictors of stress fractures.Setting: A military training installation which incorporates physical training for women.Subjects: Forty-nine female soldiers with confirmed stress fractures (cases) and 78 female soldiers with no orthopedic injuries (controls), aged 18 to 33 years.Measures: Retrospective self-reports of habitual exercise, sports participation, and food intake; current height, weight, and body mass index (BMI); demographic variables (age, ethnicity, menstrual patterns, smoking habits); and bone density on radiologically defined stress fractures.Results: Cases and controls were similar in height, weight, and BMI. Measurements of bone density (g/cm2) at the trochanter (cases, 0.77±0.09; controls, 0.77±0.08); femoral neck (cases, 0.94±0.10; controls, 0.94±0.09); ...

Mary S. Ozburn

Papers

Pubic ramus and adductor insertion stress fractures in female basic trainees.