Introduction: Stress fractures comprise a major problem in female police or army recruits. The incidence of stress fractures is reported ranging from 3 to 10 fold when compared to male recruits taking the same training program. This study consisted of an intervention program aiming at reducing combat gear weight and locating the gear as close as possible to the body center of gravity.

Material and Methods: In a prospective study we followed up two companies of female recruits of the Israel Border Police. Both companies were followed for the four months of basic training using a basic data questionnaire inclusive of previous physical activity habits, previous acute and overuse injuries, menstrual history and previous smoking habits. An injury questionnaire was filled on commencement of the course and every two weeks thereafter. The clinical records of medic and doctor visits, as well as the personal medical file, were revised. Roentgenological and scintigraphic imaging were performed during the course, when clinical suspicion of a stress fracture arose.

The first company of 71 fighters used the standard combat gear amounting to 12.5 kg. The second company of 64 fighters used combat equipment weighing 9.4 kg, held in a combat girdle close to the body center of gravity, inclusive of a shorter personal combat riffle and personal combat vest.

Results: There was no difference in the number of clinic visits between the two companies. Complaints suggesting stress fractures were recorded in the first company from the 3^rd to the 8^th week of training and in the second from the 1^st to 3^rd week. The percentage of fighters sent for Scintigraphy because of clinical suspicion of stress fractures was 22.5% in the first company and 6.25% in the second. The percentage of fighters in whom stress fractures were located by Scintigraphy was 15.5% in the first company and 4.7% in the second. The number of stress fractures in average per fighter was 0.45 fractures in the first company and 0.27 fractures in the second. When calculating only “dangerous” stress fractures (long bones and navicular) there were noted 0.34 fractures per fighter in the first company and 0.20 in the second. Total average training days lost for reason of stress fractures was 2.21 per fighter in the first company and 1.08 in the second.

Conclusions: Reducing the weight of the fighting gear and securing it closer to the body center of gravity may have a positive effect in reducing the incidence of stress fractures in female recruits of fighting units during the intense basic training program.

Background: Female recruits are known to have a relatively high incidence of stress fractures (SF). This has been apparent also when female recruits entered the Israel Border Police training program.

Aims: To examine the influence of various interventions including shoe modification, nutrition, controlled training program and pre-recruit course on the incidence of SF.

Methods: Between February 1996 and February 1998, five courses of female recruits were held with a total of 229 participants. The four later courses were controlled and strictly documented. These included 203 recruits. The total number of SF was recorded using bone scintigraphy. “Dangerous SFX” was described as those SF including the long bones of the lower limb and the navicular bone. Due to high number of SF the organic medical team introduced various interventions: 1. Shoes were replaced with lither and flexible shoes with soft absorbing soles (course I onward). 2. Nutrition was modified (course II onward). 3. A training scale was programmed and introduced (course III onward). 4. Selecting candidates six months before recruitment and running a three-month preparation course (course IV onward).

Results: 1) 55 recruits (of 203) or 27.1% suffered SF grade I or more (2.9 SF for injured recruit or 0.78 SF for each recruit in the course. 2) 36 recruits (of 203) or 17.7% suffered SF grade II or more (2.1 SF for injured recruit or 0.37 SF for each recruit in the course. 3) The data concerning 229 recruits along the 5 courses was recorded and found that the incidence of number of recruits suffering dangerous SF in all grades, or grade II or higher, and the number of dangerous SF per recruit was reduced gradually from course to course.

Conclusions: The incidence of stress fractures in female recruits during basic training is high, ranging in the series for the various courses from 23% to 35% for all grades and from 8.3% to 19% for “dangerous” SF (basically of the long bones) graded II onward. Various interventions including shoe modification, nutrition, controlled training program and pre-recruit course seems to have a possible combined effect in reducing the incidence and severity of stress fractures, especially those termed “dangerous stress fractures”.