QUITE apart from the academic consideration that vital and medical statistics now form an obligatory part of the education of students seeking the University of London's diploma in public health, the demand for information about the methods of vital and medical statistics is increasing. The most casual reader of the newspapers is now aware that population problems are of serious practical importance and that the publications of the General Register Office cannot be ignored. It is scarcely an exaggeration to say that the recently issued preliminary report on the census of 1931 is one of the most sensational documents which has appeared for years, and that he who reads it intelligently will understand what is meant by saying that civilisation is in the melting pot. An Introduction to Medical Statistics. By Hilda M. Woods William T. Russell. Pp. x + 125. (London: P. S. King and Son, Ltd., 1931.) 7s. 6d.

/pdf/an-introduction-to-medical-statistics-58gm2cuxfv.pdf

An Introduction to Medical Statistics

The purpose of this study was to evaluate the physical demands of English Football Association (FA) Premier League soccer of three different positional classifications (defender, midfielder and striker). Computerised time-motion video-analysis using the Bloomfield Movement Classification was undertaken on the purposeful movement (PM) performed by 55 players. Recognition of PM had a good inter-tester reliability strength of agreement (κ = 0.7277). Players spent 40.6 ± 10.0% of the match performing PM. Position had a significant influence on %PM time spent sprinting, running, shuffling, skipping and standing still (p 0.05). Players spent 48.7 ± 9.2% of PM time moving in a directly forward direction, 20.6 ± 6.8% not moving in any direction and the remainder of PM time moving backward, lateral, diagonal and arced directions. The players performed the equivalent of 726 ± 203 turns during the match; 609 ± 193 of these being of 0° to 90° to the left or right. Players were involved in the equivalent of 111 ± 77 on the ball movement activities per match with no significant differences between the positions for total involvement in on the ball activity (p > 0.05). This study has provided an indication of the different physical demands of different playing positions in FA Premier League match-play through assessment of movements performed by players.

Physical demands of different positions in FA Premier League soccer

This review discusses human thermoregulation during exercise and the measurement of body temperature in clinical and exercise settings. The thermoregulatory mechanisms play important roles in maintaining physiological homeostasis during rest and physical exercise. Physical exertion poses a challenge to thermoregulation by causing a substantial increase in metabolic heat production. However, within a non-thermolytic range, the thermoregulatory mechanisms are capable of adapting to sustain physiological functions under these conditions. The central nervous system may also rely on hyperthermia to protect the body from "overheating." Hyperthermia may serve as a self-limiting signal that triggers central inhibition of exercise performance when a temperature threshold is achieved. Exposure to sub-lethal heat stress may also confer tolerance against higher doses of heat stress by inducing the production of heat shock proteins, which protect cells against the thermolytic effects of heat. Advances in body temperature measurement also contribute to research in thermoregulation. Current evidence supports the use of oral temperature measurement in the clinical setting, although it may not be as convenient as tympanic temperature measurement using the infrared temperature scanner. Rectal and oesophagus temperatures are widely accepted surrogate measurements of core temperature (Tc), but they cause discomfort and are less likely to be accepted by users. Gastrointestinal temperature measurement using the ingestible temperature sensor provides an acceptable level of accuracy as a surrogate measure of Tc without causing discomfort to the user. This form of Tc measurement also allows Tc to be measured continuously in the field and has gained wider acceptance in the last decade.

https://www.annals.edu.sg/PDF/37VolNo4Apr2008/V37N4p347.pdf

Human thermoregulation and measurement of body temperature in exercise and clinical settings.

ASB Clinical Biomechanics Award Winner 2006 Prospective study of the biomechanical factors associated with iliotibial band syndrome

Cardiovascular disease (CVD) is the leading cause of on-duty death among firefighters (45% of on-duty fatalities) and a major cause of morbidity CVD in the fire service also has adverse public safety implications as well as significant cost impacts on government agencies Over the last decade, our understanding of CVD among firefighters has significantly improved and provides insight into potential preventive strategies The physiology of cardiovascular arousal and other changes that occur in association with acute firefighting activities have been well-characterized However, despite the strenuous nature of emergency duty, firefighters' prevalence of low fitness, obesity, and other CVD risk factors are high Unique statistical approaches have documented that on-duty CVD events do not occur at random in the fire service They are more frequent at certain times of day, certain periods of the year, and are overwhelmingly more frequent during strenuous duties compared with nonemergency situations Moreover, as expected on-duty CVD events occur almost exclusively among susceptible firefighters with underlying CVD These findings suggest that preventive measures with proven benefits be applied aggressively to firefighters Furthermore, all fire departments should have entry-level medical evaluations, institute periodic medical and fitness evaluations, and require rigorous return to work evaluations after any significant illness Finally, on the basis of the overwhelming evidence supporting markedly higher relative risks of on-duty death and disability among firefighters with established coronary heart disease, most firefighters with clinically significant coronary heart disease should be restricted from participating in strenuous emergency duties

Cardiovascular disease in US firefighters: a systematic review.

Telemetric gastrointestinal (GI) temperature pills are now commonly used to measure core body temperature and could minimize the risk of heat illness while maximizing operational effectiveness in workers subject to high levels of thermal strain.

Purpose: To quantify the effect of repeated cool water ingestion on the accuracy of GI pill temperature.

Methods: Ten operational firefighters ingested a pill to measure GI temperature (T1int) before overnight sleep. Two hours following breakfast and 11.5 h after ingesting T1int, the firefighters ingested a second pill (T2int) before performing 8.5 h of intermittent activity (repetitive cycles of 30 min of seated rest followed by 30 min of general firefighter duties). During the first 2 min of each 30-min rest period, the firefighters consumed 250 mL of chilled water (5-8[degrees]C).

Results: Water ingestion had a highly variable effect both within and between subjects in transiently (32 +/- 10 min) reducing the temperature of T2int in comparison with T1int. In general, this transient reduction in T2int became progressively smaller as time following ingestion increased. In some firefighters, the difference between T1int and T2int became negligible (+/- 0.1[degrees]C) after 3 h, whereas in two others, large differences (peaking at 2.0[degrees]C and 6.3[degrees]C) were still observed when water was consumed 8 h after pill ingestion.

Conclusion: These results show that a GI pill ingested immediately prior to physical activity cannot be used to measure core body temperature accurately in all individuals during the following 8 h when cool fluids are regularly ingested. This makes GI temperature measurement unsuitable for workers who respond to emergency deployments when regular fluid consumption is recommended operational practice.

The effect of cool water ingestion on gastrointestinal pill temperature.

This study aimed to identify risk factors for training injuries resulting in referral to a remedial instructor (RI) or medical discharge (MD) among British Army recruits undertaking initial training. Physical performance and anthropometric data for 11,937 male and 1,480 female recruits were examined as potential risk factors for RI referral and MD, using Cox regression. There was a trend showing that female recruits' MD rates were higher than male recruits' rates (p = 0.096), and RI referral rates were significantly greater for women than for men (p = 0.041). The independent risk factors for MD were 2.4-km run time, ethnicity, and Army training regiment attended (p < 0.001), and those for RI referral were 2.4-km run time, ethnicity, Army training regiment attended, and body mass index (p < 0.001). Gender was not an independent risk factor for injury, suggesting that lower levels of aerobic fitness are the primary cause of the greater incidence of injury among female recruits during British Army initial training.

/pdf/risk-factors-for-training-injuries-among-british-army-4o6a74384j.pdf

Risk Factors for Training Injuries among British Army Recruits

Strategies to combat heat strain during and after firefighting

PURPOSE: Blackcurrant intake increases peripheral blood flow in humans, potentially by anthocyanin-induced vasodilation which may affect substrate delivery and exercise performance. We examined the effects of New Zealand blackcurrant (NZBC) extract on substrate oxidation, cycling time-trial performance and plasma lactate responses following the time-trial in trained cyclists. 
METHODS: Using a randomized, double-blind, crossover design, fourteen healthy men (age: 38 ± 13 years, height: 178 ± 4 cm, body mass: 77 ± 9 kg, VO2max: 53 ± 6 ml·kg-1·min-1, mean ± SD) ingested NZBC extract (300 mg∙day-1 CurraNZ™ containing 105 mg anthocyanin) or placebo (PL, 300 mg microcrystalline cellulose M102) for 7-days (washout 14-days). On day 7, participants performed 30 min of cycling (3x10 min at 45, 55 and 65% VO2max), followed by a 16.1 km time-trial with lactate sampling during a 20-minute passive recovery. 
RESULTS: NZBC extract increased fat oxidation at 65% VO2max by 27% (P < 0.05) and improved 16.1 km time-trial performance by 2.4% (NZBC: 1678 ± 108 s, PL: 1722 ± 131 s, P < 0.05). Plasma lactate was higher with NZBC extract immediately following the time-trial (NZBC: 7.06 ± 1.73 mmol∙L-1, PL: 5.92 ± 1.58 mmol∙L-1 P < 0.01). 
CONCLUSIONS: Seven days intake of New Zealand blackcurrant extract improves 16.1 km cycling time-trial performance and increases fat oxidation during moderate intensity cycling.

/pdf/new-zealand-blackcurrant-extract-improves-cycling-oj9rqd81j2.pdf

New Zealand blackcurrant extract improves cycling performance and fat oxidation in cyclists.

The aim of this study was to quantify the physiological responses of Police Officers wearing chemical, biological, radiological and nuclear personal protective equipment (CBRN PPE) during firearms house entry (FE) unarmed house entry (UE) and crowd control (CC) simulations Participants volunteered from the UK Police Force [FE (n = 6, age 33 ± 4 years, body mass 853 ± 79 kg, [Vdot]O2max 53 ± 5 ml · kg−1 · min−1), UE and CC (n = 11, age 34 ± 5 years, body mass 885 ± 138 kg, [Vdot]O2max 51 ± 5 ml · kg−1 · min−1)] Heart rate reserve (HRR) during FE was greater than UE (74 ± 7 vs 62 ± 6%HRR, p = 001) but lower in CC (39 ± 7%HRR, p < 001) Peak core body temperature was greater during FE (392 ± 03°C) than UE (389 ± 04°C, p < 001) and CC (375 ± 03°C, p < 001), with similar trends in skin temperature There were no differences in the volume of water consumed (113 ± 044 l, p = 051) or change in body mass (−168 ± 065 kg, p = 074) between simulations The increase in body temperature was a pri

Sam D. Blacker

Papers

The effect of cool water ingestion on gastrointestinal pill temperature.

Risk Factors for Training Injuries among British Army Recruits

Strategies to combat heat strain during and after firefighting

New Zealand blackcurrant extract improves cycling performance and fat oxidation in cyclists.

Physiological responses of Police Officers during job simulations wearing chemical, biological, radiological and nuclear personal protective equipment