Changes in physical performance, body composition and physical training during military operations: systematic review and meta-analysis.

Systematic review and meta-analysis applying PRISMA guidelines with a PICOS format was constructed to provide an overview of changes in physical performance, body composition and physical training in soldiers during prolonged (≥ 3 months) military operations. Twenty-four studies out of the screened 4431 records filled the inclusion criteria. A small decrease in endurance performance was the most consistent finding (Hedge's g [g] - 0.21, 95% CI - 0.01 to - 0.41) while small overall increases in maximal strength of the lower (g 0.33, 95% CI 0.16-0.50) and upper body (g 0.33, 95% CI 0.19-0.46) were observed. In addition, small increases in strength endurance (push-up, g 0.34, 95% CI 0.15-0.52; sit-up g 0.26, 95% CI 0.07-0.44) were observed. The overall changes in body composition were trivial. Heterogeneity in the outcome variables varied mainly between low to moderate. Large inter-individual variations were observed in physical training volume, including decrements especially in endurance training frequency and volume. A reduction in total training load was often associated with negative changes in body composition and physical performance according to the principle of training specificity. Individuals with higher initial fitness level were more susceptible to decrements in their physical performance during operation.

Physical fitness and anthropometrics in Finnish soldiers during their early career: prospective changes during a 3-year follow-up.

INTRODUCTION: Physical fitness is a fundamental capability required of military personnel, but studies focusing on longitudinal changes in physical fitness and anthropometrics in soldiers are lacking. The aim was to evaluate physical fitness and anthropometrics in soldiers during their early career. METHODS: A 3-year prospective study included 180 male soldiers (baseline age 26±2 years) with measures of a 12 min running test, standing long jump, sit-up and push-up tests, and body mass, height and waist circumference (WC). Baseline data were stratified into tertiles, and the changes within each tertile were analysed using dependent t-tests and analysis of variance. RESULTS: 12 min running test distance decreased on average by 2% (-54 m), sit-up performance 3% (-1.5 repetitions (reps)/min), push-up performance 4% (-1.9 reps/min) and standing long jump performance 1% (-2.1 cm) over the 3-year period (p<0.05). Both aerobic and muscular fitness decreased consistently among the highest baseline tertile (12 min running test: -70 m, sit-ups: -3.2 reps/min, push-ups: -7.5 reps/min, standing long jump: -5.5 cm; p<0.001), whereas both aerobic and muscular fitness levels were maintained and push-up performance was improved (p<0.05) in the lowest baseline tertiles. Body mass increased on average by 4% (+3.4 kg) and WC by 4% (+3.9 cm) (p<0.001), and these increases were observed for all baseline tertiles (p<0.05). CONCLUSIONS: Small decrements in physical fitness and anthropometrics exist during the early career of soldiers. The changes in physical fitness differed according to baseline fitness levels. The results indicate that support for exercise training may be needed even in a soldier's early career.

Aerobic fitness predicted by demographics, anthropometrics, health behaviour, physical activity and muscle fitness in male and female recruits entering military service.

INTRODUCTION: The physical and mental training load can be high during military service. Therefore, tailored preconditioning programmes based on assessment of physical fitness could increase readiness for military service, especially among those ones with lower baseline fitness level. The purpose of present study was to investigate how self-assessed health behaviour, physical activity and muscle fitness can predict physical fitness in young male and female military cohorts. METHODS: Demographics, health behaviour and daily physical activity preceding military service were surveyed by a questionnaire. Thereafter, physical fitness was assessed during the military service by the tests of 12 min running, 1 min push-ups and sit-ups. Explosive power of the lower extremities was studied by maximal standing long jump. Measurements of body anthropometry consisted of body mass, height, and waist circumference. RESULTS: The two strongest individual predictors of objectively measured running distance in 12 min were self-reported physical activity and physical readiness in both men and women. Self-reported physical activity, readiness for military service, sitting time, education, smoking and body anthropometrics together explained 52% of the variance in the 12 min running test result (R2=0.52, mean absolute percentage error (MAPE) 8.8%, mean absolute error (MAE) 207 m) in men, while for women the predictive values were weaker. Addition of muscle fitness results to the adjusted regression model further improved the model, which explained 59% of the variance in the 12 min running tests result of male conscripts (R2=0.59, MAPE 7.8%, MAE 181 m). CONCLUSION: In the present study, self-reported physical activity, muscle fitness, physical readiness for military service, sitting time, education, smoking and body anthropometrics predicted inadequately the measured endurance capacity among recruits. The present questionnaire-based variables do not accurately predict physical fitness of recruits and thus, they are not either suitable for practical use for preconditioning programmes or preselection before entering the military service.

Changes in physical fitness and anthropometrics differ between female and male recruits during the Finnish military service.

INTRODUCTION: Military training programmes are often similar for male and female recruits despite sex differences in physical performance that may influence training adaptations during military service. The present study aimed to compare changes in physical fitness and anthropometrics between Finnish female and male recruits during military service. METHODS: A total of 234 690 male and 3549 female recruits participated in fitness tests at the beginning and end of military service between 2005 and 2015. Anthropometric measurements were body mass, height, body mass index (BMI) and waist circumference (WC). Fitness tests consisted 12 min running, standing long jump, and sit-ups and push-ups. RESULTS: No changes were observed in anthropometrics, while both sexes improved most of the fitness test results. After adjustment for service time, branch, age, initial fitness test results, BMI and WC, improvement in running test performance was 158 m (95% CI 142 to 173, p≤0.001) greater in male than female recruits. Similarly, improvements were larger in male recruits for push-ups (5 reps/min, 95% CI 5 to 6, p≤0.001), sit-ups (2 reps/min, 95% CI 2 to 3, p≤0.001) and standing long jump (12 cm, 95% CI 11 to 13, p≤0.001) when compared with women. CONCLUSIONS: The study revealed sex differences in adaptations to the standardised military training. Both male and female recruits improved their physical fitness, but smaller gains were observed in women using the same training programme. The mechanisms explaining sex differences in adaptations to military training, and whether tailored training programmes are needed specifically for female recruits to reduce sex differences during military service, warrants further studies.

Identification limits for volatile organic compounds in the blood by purge-and-trap GC-FTIR.

An analysis method for volatile organic compounds in blood based on purge-and-trap extraction coupled with gas chromatography-Fourier transform infrared spectroscopy (GC-FTIR) was developed. The sample volume was 5 mL, and the internal standard was diethyl ketone. The chromatographic separation was carried out on a PoraPLOT Q capillary column, and the effluent was first directed to the FTIR and then to a flame ionization detector (FID). FTIR identification limits were measured for 27 volatile organic compounds; the criteria for the limit were that the first hit-list position should be obtained against the Sadtler library, which contains 3240 spectra, and that the correlation value should exceed 0.5. It was required that the peak be seen by FID but not necessarily by a Gram-Schmidt chromatogram. The FTIR identification limits, ranging from 0.01 mg/L for ethyl acetate, methylethyl ketone, and sevoflurane to 24 mg/L for methanol, generally allowed the detection of volatile-substance exposure at a lower level than is acutely toxic. Quantitative calibration data were presented for selected substances, based on the FID response, which shows that the method is also amenable to quantitative analysis. The throughput of the method without additional automation is five samples per day, the purge-and-trap stage being the limiting factor.

Analytical toxicology of fluorinated inhalation anaesthetics.

The chemical and pharmacological properties of the current fluorinated inhalation anaesthetics, halothane, enflurane, isoflurane, sevoflurane and desflurane, are surveyed with implications to toxicity. Analytical methods, especially gas chromatography with head space, purge and trap, or pulse heating extraction, are reviewed in forensic toxicological and occupational/therapeutic monitoring contexts.