Altered dynamic postural stability and joint position sense following British Army foot-drill

Impaired proprioceptive acuity negatively affects both joint position sense and postural control and is a risk factor for lower-extremity musculoskeletal injury in athletes and military personnel. British Army foot-drill is an occupational military activity involving cyclical high impact loading forces greater than those observed in athletes during high level plyometrics. Foot-drill may contribute to the high rates of lower-extremity overuse injuries observed in recruits during basic training. There is limited research investigating foot-drill specific injury risk factors in women. This study aimed to quantify changes in ankle joint proprioception and dynamic postural stability following a period of British Army foot-drill. Fourteen recruit age-matched women underwent pre-post foot-drill measures of frontal plane ankle joint position sense (JPS) and dynamic postural stability using the dynamic postural stability index (DPSI). Passive ankle JPS was assessed from relative test angles of inversion (IN) and eversion (EV) 30% and IN60% using an isokinetic dynamometer. The DPSI and the individual stability indices (medio-lateral [MLSI], anterior-posterior [APSI] and vertical [VSI]) were calculated from lateral and forward jump-landing conditions using force plates. Foot-drill was conducted by a serving British Army drill instructor. Significantly greater absolute mean JPS error for IN30% and EV30% was observed post foot-drill (p ? 0.016, d ? 0.70). For both the lateral and forward jump-landing conditions, significantly greater stability index scores were observed for MLSI, APSI and DPSI (p ? 0.017, d ? 0.52). Significantly greater JPS error and stability index scores are associated with the demands of British Army foot-drill. These results provide evidence that foot-drill negatively affects lower-extremity proprioceptive acuity in recruit age-matched women, which has implications for increased injury risk during subsequent military physical activity, occurring in a normal training cycle

Wearable Devices Suitable for Monitoring Twenty Four Hour Heart Rate Variability in Military Populations

Heart rate variability (HRV) measurements provide information on the autonomic nervous system and the balance between parasympathetic and sympathetic activity. A high HRV can be advantageous, reflecting the ability of the autonomic nervous system to adapt, whereas a low HRV can be indicative of fatigue, overtraining or health issues. There has been a surge in wearable devices that claim to measure HRV. Some of these include spot measurements, whilst others only record during periods of rest and/or sleep. Few are capable of continuously measuring HRV (≥24 h). We undertook a narrative review of the literature with the aim to determine which currently available wearable devices are capable of measuring continuous, precise HRV measures. The review also aims to evaluate which devices would be suitable in a field setting specific to military populations. The Polar H10 appears to be the most accurate wearable device when compared to criterion measures and even appears to supersede traditional methods during exercise. However, currently, the H10 must be paired with a watch to enable the raw data to be extracted for HRV analysis if users need to avoid using an app (for security or data ownership reasons) which incurs additional cost

Wearable Devices Suitable for Monitoring Twenty Four Hour Heart Rate Variability in Military Populations

Heart rate variability (HRV) measurements provide information on the autonomic nervous system and the balance between parasympathetic and sympathetic activity. A high HRV can be advantageous, reflecting the ability of the autonomic nervous system to adapt, whereas a low HRV can be indicative of fatigue, overtraining or health issues. There has been a surge in wearable devices that claim to measure HRV. Some of these include spot measurements, whilst others only record during periods of rest and/or sleep. Few are capable of continuously measuring HRV (≥24 h). We undertook a narrative review of the literature with the aim to determine which currently available wearable devices are capable of measuring continuous, precise HRV measures. The review also aims to evaluate which devices would be suitable in a field setting specific to military populations. The Polar H10 appears to be the most accurate wearable device when compared to criterion measures and even appears to supersede traditional methods during exercise. However, currently, the H10 must be paired with a watch to enable the raw data to be extracted for HRV analysis if users need to avoid using an app (for security or data ownership reasons) which incurs additional cost

Table_1_Sleep duration and perceptions of sleep quality in British Army recruits during basic training - an observational analysis.xlsx

IntroductionSleep is critical to the health, wellbeing and performance of military personnel during basic training. This two-part study evaluated sleep-wake patterns and sleep disturbances in junior soldiers (JS) and infantry recruits in Autumn 2021 (study 1), and non-infantry recruits in spring 2022 (study 2).MethodsDuring studies 1 and 2, validated wearable technology combined with a sleep diary was used to quantify sleep-wake indices, sleep disturbances and perceptions of sleep quality. Sleep diary data was analysed descriptively. A series of repeated-measures ANOVAs examined differences in objective sleep-wake indices. Correlation analysis determined associations between time in bed (TIB) and total sleep time (TST).ResultsSignificant (p Discussion/ConclusionOur findings contribute to the existing evidence that long-term sleep loss is pervasive during initial military training programmes. The average sleep durations indicate chronic and unrecoverable sleep loss which would be expected to significantly impair physical and cognitive military performance, and increase the risk of injury, illness and attrition rates during basic training. Changes in the design and scheduling of basic training programmes to enable, at the least, minimum sleep recommendations to be met, and to improve sleep hygiene in the primary sleeping environment are warranted.</p

Modelling the implications of reducing smoking prevalence : the benefits of increasing the UK tobacco duty escalator to public health and economic outcomes

INTRODUCTION: Taxing tobacco is one of the most effective ways to reduce smoking prevalence, mitigate its devastating consequential health harms and progress towards a tobacco-free society. This study modelled the health and economic impacts of increasing the existing cigarette tobacco duty escalator (TDE) in the UK from the current 2% above consumer price inflation to 5%. METHODS: A two-stage modelling process was used. First, a non-linear multivariate regression model was fitted to cross-sectional smoking data, creating longitudinal projections from 2015 to 2035. Second, these projections were used to predict the future incidence, prevalence and cost of 17 smoking-related diseases using a Monte Carlo microsimulation approach. A sustained increase in the duty escalator was evaluated against a baseline of continuing historical smoking trends and the existing duty escalator. RESULTS: A sustained increase in the TDE is projected to reduce adult smoking prevalence to 6% in 2035, from 10% in a baseline scenario. After increasing the TDE, only 65% of female and 60% of male would-be smokers would actually be smoking in 2035. The intervention is projected to avoid around 75 200 new cases of smoking-related diseases between 2015 and 2035. In 2035 alone, £49 m in National Health Service and social care costs and £192 m in societal premature mortality and morbidity costs are projected to be avoided. CONCLUSION: Increasing the UK TDE to 5% above inflation could effectively reduce smoking prevalence, prevent diseases and avoid healthcare costs. It would deliver substantial progress towards a tobacco-free society and should be implemented by the UK Government with urgency

Changes in Physical Performance during British Army Junior Entry, British Army Standard Entry, and Royal Air Force Basic Training

Introduction: To quantify changes in physical performance in men and women during British Army Junior Entry (Army-JE), Standard Entry (Army-SE), and Royal Air Force (RAF) Basic Training (BT). Design: Prospective longitudinal study. Methods: 381 participants [(339 men, 42 women) n=141 Army-JE; n=132 Army-SE; n=108 RAF] completed a 2-km Run, Medicine Ball Throw (MBT) and isometric Mid-Thigh Pull (MTP), pre- and post-BT. To examine changes in pre- to post- BT physical test performance, for each course, paired students t-tests, and Wilcoxon tests were applied to normally and non-normally distributed data respectively; with effect sizes reported as Cohen’s D and with rank biserial correlations, respectively. A one-way between-subjects ANOVA (or Welch ANOVA for non-normally distributed data) compared performance between quartiles based on test performance pre-BT. Where the main tests statistic, p value and effect sizes identified likely effect of quartile, post-hoc comparisons were made using Games-Howell tests with Tukey’s p value. Data are presented as mean ± standard deviation, statistical significance set at p<0.05. Results: During BT, 2-km run time improved by 13±46 (-2.1±8.1%), 30±64 (-4.8±12.3%), and 24±27 s (-4.5±5.1%) for Army-JE, Army-SE, and RAF, respectively (all p<0.005). MBT distance increased by 0.27±0.28 m (6.8±7.0%) for Army-JE (p<0.001) and 0.07±0.46 m (2.3±10.9%) for Army-SE (p=0.040), but decreased by 0.08±0.27 m (-1.4±6.0%) for RAF (p=0.002). MTP force increased by 80±281 N (10.8±27.6%) for Army-JE (p<0.001) and did not change for Army-SE (-36±295 N, -0.7±20.6%, p=0.144) or RAF (-9±208 N, 1.0±17.0, p=0.603). For all tests and cohorts, participants in the lowest quartile of pre-BT performance scores demonstrated greater improvements, compared with participants in the highest quartile (except Army-JE MBT; ∆% change similar between all quartiles). Conclusions: Changes in physical performance were observed for the three fitness tests following the different BT courses, but recruits with the lowest strength and aerobic fitness experienced greatest improvements