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Background The aim of this study was to compare the outcome of patients who have undergone distal biceps tendon repair by a single-incision Endobutton fixation technique with the results of another cohort of patients who elected not to undergo surgery for distal biceps tendon rupture. Methods A retrospective cohort study was performed of patients diagnosed with distal biceps ruptures, repaired with an Endobutton (Smith & Nephew, Andover, MA, USA) technique or treated nonoperatively by the senior surgeon (S.A.S.). With a minimum follow-up of 6 months, a routine elbow examination, radiographs, and functional questionnaires were performed. Isometric supination, flexion, and grip strength was measured using a BTE machine (Baltimore Therapeutic Equipment, Hanover, MD, USA). There were 47 patients available for follow-up with 50 distal biceps ruptures; 40 ruptures have undergone repair, and 10 have been managed nonoperatively. Three patients had sustained bilateral ruptures. Results There was a significant difference in flexion and supination isometric strength between the operative and nonoperative cohorts compared with the uninjured contralateral side (92.94% vs. 70.65%, P = .01512; 87.91% vs 59.11%, P = .00414, respectively). The difference in grip strengths between the 2 cohorts compared with the uninjured side was not significant (100.00% vs. 79.16%; P = .16002). The operated cohort had significantly better QuickDASH score, Oxford Elbow Score, and Mayo Elbow Performance Score (6.29 vs. 14.10, P = .02123; 44.71 vs. 38.70, P = .00429; 93.13 vs. 84.50, P = .01423). Conclusion Repair of distal biceps ruptures using an Endobutton fixation results in nearly normal return of strength and function, which is significantly better than in those managed nonoperatively. Level of evidence Level III, Retrospective Cohort Design; Treatment Study

Background A novel ibuprofen (IBU) formulation, Advil® Film-Coated Tablets (IBUNa), was developed. Objective Pharmacokinetic comparison of IBUNa versus other IBU formulations. Study Design Two randomized, single-dose, open-label, five-way crossover pharmacokinetic studies. Setting Inpatient research clinic. Subjects Seventy-one healthy adult volunteers. Intervention Study 1: In three periods, fasted subjects received 400-mg IBU dose equivalents as IBUNa 2 × 256 mg, Advil® Liqui-Gels® (IBULG) 2 × 200 mg, and Motrin® IB (IBUMot) 2 × 200 mg tablets. In two periods following a high-fat breakfast, subjects received 400-mg IBU dose equivalents as IBUNa 2 × 256 mg and IBULG 2 × 200 mg. Study 2: In five study periods, fasted subjects received 400-mg IBU dose equivalents as IBUNa 2 × 256 mg, Advil® FastGel® (IBUFG) 2 × 200 mg, Nurofen® (IBUNur) 2 × 200 mg, Advil® (IBUAdv) 2 × 200 mg, and Nurofen® Express containing IBU lysinate (IBULys) 2 × 342 mg. Main Outcome Measure Log-transformed area under the plasma concentration versus time curve to last observable concentration (AUCL) and maximum plasma concentration (Cmax) were the primary pharmacokinetic parameters; time to maximum measured plasma concentration (Tmax) was analyzed post hoc. Results IBUNa was bioequivalent to IBULG (fasted and fed) and IBUFG and IBULys (fasted) for rate (Cmax) and extent (AUCL) of IBU absorption. After fasting, AUCL was bioequivalent for IBUNa and IBUMot, IBUAdv, and IBUNur, but Cmax occurred significantly earlier with IBUNa. After fasting, median IBUNaTmax was comparable to that for IBULG, IBUFG, and IBULys, but was much shorter than that for IBUMot, IBUNur, and IBUAdv. Food slowed absorption of IBUNa and IBULG similarly. All treatments were tolerated similarly. Conclusion IBUNa is absorbed faster but to a similar extent as standard IBU formulations.

Demands on publicly funded ophthalmic services worldwide continue to increase with new treatments, waiting time targets, working time limits, and restricted budgets. These highlight the necessity to develop innovative ways of utilising existing capacity more effectively. A new regional, fully electronic ophthalmic-referral service with digital imaging was trialled using existing information-technology (IT) infrastructure. Following successful pilot study, the service was rolled out regionally. Service delivery data was prospectively collated for all the attendances in the year prior to (2006) and the year following (2008) introduction. Comparing 2006 against 2008, median waiting times reduced (14 vs 4 weeks), and fewer new patients were observed (8714 vs 7462 P

The objective of this study was to determine the change in elite dinghy sailor's knowledge and use of sport science, three years after the adoption of a sport science support (SSS) programme by Yachting New Zealand for its elite dinghy sailors. A questionnaire was administered to 28 (22 male, six female) elite sailors in April 1994 and to 33 (24 male and nine female) in March 1997 during a training camp for elite sailors. 15 of the sailors participated in 1994 and 1997. The questionnaire asked whether or not the sailors used a training race diary and inquired about their knowledge and use of sport science in the areas of nutrition, psychology and physical conditioning. In 1997, additional questions enquired about sailor's perception of sport science and its affect on their racing performance. Between April 1994 and March 1997, sailors received sport science support in nutrition, psychology and physical conditioning. Sailors reported a greater amount of fluid drunk on a four-hour sail in 1997 than in 1994 and a greater proportion of sailors ate a high carbohydrate meal after a race in 1997 than in 1994. In 1997, sailors reported feeling less anxiety before a race, and the sailors common to 1994 and 1997 reported feeling less sick before a race in 1997 than in 1994. Increases were observed in volume and intensity of physical training, and improvements were noticed in the chosen type of aerobic training in 1997. Most sailors believed that their knowledge and use of sport science has increased and that their increased use of sport science has led to improvements in racing performance. The results suggest that elite New Zealand sailors' use of sport science improved in the areas of nutrition, sports psychology and physical conditioning between 1994 and 1997. However, when the results were compared with those of Legg and Mackie (1999), it was evident that greater physical conditioning improvements had occurred between 1994 and 1995 than had been sustained since, while the majority of sailor's sport psychology improvements occurred between 1995 and 1997. Sailors reported fluid intake between 1994 and 1997 had steadily improved. The reason for sailor's change in emphasis on different areas of sport science over time may be a result of their adopting ideas with which they were most familiar (physical conditioning and nutrition) first, and then adopting the less widely understood discipline of sport psychology once they felt that they had mastered their use of physical conditioning and nutrition. This study indicates that sailors are beginning to understand the importance of personal preparation using sport science principles.

The purpose of this study was to evaluate the influence of British army recruit training on the physical fitness and strength of female recruits. A total of 73 females (aged 17-23 years) of a single intake of Women's Royal Army Corps (WRAC) recruits were tested at the beginning and end of their 6-week recruit training programme at the WRAC training centre, Guildford. The battery of tests comprised the maximal cycle time for a standard NATO test as an indirect method of determination of maximal oxygen intake (VO2 max) using a cycle ergometer; maximal isometric hand grip strength (Max Grip); maximal isometric 38 cm upright pull strength (Max 38) and maximal incremental dynamic lift to 152 cm (IDL 152). In addition, body-weight and the sum of biceps, triceps, suprailiac and subscapular skinfold thicknesses were measured in order to assess alterations in fat-free mass and percentage of body fat (BF). The recruits responded to training with significant increases in mean VO2 max from 45.7 ml kg-1 min-1 (SD = 5.2) to 46.7 ml kg-1 min-1 (SD = 4.4) or 2.2% (p.05), mean Max Grip from 263.1 N (SD = 52.2) to 304.9 N (SD = 54.0) or 15.9% (p0.001) and mean IDL 152 from 328.0 N (SD = 78.1) to 361.2 N (SD = 74.6) or 10.1% (p0.001). There was a significant increase in the mean body-weight of 0.61 kg or 1% (p0.05), mean fat-free mass of 1.05 kg or 2.4% (p0.001), and a significant reduction in the mean % BF by 3.3% (p0.001). It is concluded that female recruit training in the British army is effective in terms of increasing aerobic fitness, physical strength and fat-free mass and in reducing the percentage of body fat.

Sixty-two Adult Artillery Recruits, 95 Junior Infantry Soldier Recruits and 104 Junior Infantry Leader Recruits were studied before and after 3, 5 and 11 months, respectively, of British Army basic training. Before basic training the mean maximal oxygen uptake predicted from cycle ergometry (pred VO2max) for Adult Artillery Recruits was 56.1 ml (kg min)-1. It was 58.3 ml (kg min)-1 for the Junior Infantry Soldier Recruits and 58.0 ml (kg min)-1 for the Junior Infantry Leader Recruits. For Adult Artillery Recruits, after basic training there were statistically significant increases in body weight (+2.1%) and pred VO2max (+3.6%) but mixed responses for muscular strength, endurance and fatigue. For Junior Infantry Soldier Recruits, there was no significant change in body weight but a significant reduction in pred VO2max (-2.4%) and a trend towards increased isometric muscular strength. For Junior Infantry Leader Recruits, there were significant increases in body weight (+4.9%), pred VO2max (+3.0%), and isometric muscular strength. These results suggest that the intensity and nature of 3 months of basic training for Adult Artillery Recruits was sufficient to improve their aerobic fitness but was not effective in materially improving muscular strength and endurance. The intensity and nature of basic training for Junior Infantry Soldier Recruits over 5 months was effective in increasing muscular strength but resulted in a decrease in aerobic fitness possibly on account of their high initial fitness level. Basic training over 11 months for Junior Infantry Leader recruits was effective in increasing body weight, aerobic fitness and muscular strength. This may have reflected a change in the intensity and nature of training and in lifestyle after the initial 5 months of basic training, which was undertaken in common with the Junior Infantry Soldier Recruits, or it may be related to normal ageing.

We report two cases of Langerhans' cell histiocytosis with unusual central nervous system (CNS) involvement. The first patient had behavioural disturbances, memory loss and diabetes insipidus. His response to a range of treatments was poor. The second patient presented with seizures and headaches suggestive of raised intracranial pressure. Etoposide (VP16) chemotherapy led to a dramatic clinical and radiological improvement. The various CNS manifestations of Langerhans' cell histiocytosis and their management are discussed.

Previous studies have suggested that short-term whole-body vibration (WBV) training produces neuromuscular improvement similar to that of power and strength training. However, it is yet to be determined whether short-term WBV exposure produces neurogenic enhancement for power, speed, and agility. The purpose of this study was to investigate the effect short-term WBV training had on vertical jump, sprint, and agility performance in nonelite athletes. Twenty-four sport science students (16 men and 8 women) were randomly assigned to 2 groups: WBV training or control. Each group included 8 men and 4 women. Countermovement jump (CMJ) height, squat jump (SJ) height, sprint speed over 5, 10, and 20 m, and agility (505, up and back) were performed by each participant before and after 9 days of either no training (control) or WBV training. Perceived discomfort of every participant was recorded after daily WBV exposure and nonexposure. There were no significant differences between WBV and control groups for CMJ, SJ, sprints, and agility. Perceived discomfort differed between the first and subsequent days of WBV training (p < 0.05); however, there was no difference between the WBV and control groups. It is concluded that short-term WBV training did not enhance performance in nonelite athletes.

This study enquired about the knowledge and reported use of sport science in elite Olympic class sailors.The sailors responded to a simple questionnaire.The questionnaire was administered as part of an introductory seminar on sport science during a training camp.The participants were 28 (22 male, 6 female) elite New Zealand Olympic class sailors.None.The questionnaire asked whether or not they used a training race diary, enquired about their current and past injuries and their knowledge and use of sport science in the areas of nutrition, psychology and physical training.Only ten (36%) of the sailors kept a training/race diary. Whilst only four (14%) had a current injury, sixteen (57%) reported an injury in the previous three years. The injuries were in the lower back (45%), knee (22%), shoulder (18%), and arm (15%). Although nineteen (68%) of the sailors had experienced dehydration during racing, the average volume of fluid reported to be taken on a four hour sail was only 0.9 litre, of which only an average of 0.7 litres (77%) was reported to be drunk. All the sailors reported being sometimes (46%) to very often (3%) anxious before races and sometimes (43%) to always (7%) being frustrated with their own mistakes. Only one sailor reported never having negative thoughts whilst fifteen (53%) reported having them sometimes, and seven (25%) often or very often. Twenty-four (86%) of the sailors reported that they sometimes had a loss of concentration near the end of the race. Whilst eighteen (64%) reported practising relaxation and seventeen (61%) reported practising visualisation as a mental skill, only five (18%) practised progressive mental relaxation, two (7%) practised meditation and none practised yoga. Seventeen (61%) undertook strength/circuit training, ten (36%) flexibility and twenty-one (75%) off water aerobic training. Twenty-four (86%) reported undertaking on-water aerobic training.The results indicate that there is considerable scope for improvement in the knowledge and use of sports science amongst elite New Zealand Olympic class sailors.

Primary care physicians continue to play an important role in preventing HIV transmission by targeting messages to their high-risk patients. The risk of HIV transmission cannot be eliminated entirely; however, clinicians have a variety of prevention interventions at their disposal. Behavioral and therapeutic interventions offered in a client-centered environment have the greatest chance of success. Patients can benefit from individualized prevention plans that decrease risk by treating drug addiction and by modifying sexual and drug-taking behaviors. The risk of HIV infection in health care workers can be reduced by strict adherence to universal precautions and the use of postexposure antiretroviral therapy.

The purpose of this study was to compare the physical performance of elite New Zealand and other nations olympic class sailors and to undertake an initial examination of the relation between physical and sailing performance.A comparative study.Healthy elite national level olympic class sailors were examined.Thirty-one elite New Zealand Olympic sailing squad team members and 108 Olympic team sailors from ten other nations.The data for the two groups of subjects was compared using unpaired "t"-tests. A qualitative analysis was used to examine the relation between physical and sailing performance.Measurements included age, body mass, muscular strength endurance (as assessed by the maximum number of push-ups, pull-ups and sit-ups that could be performed) and serobic power (as assessed by the time taken to cover 2500 m and the distance completed in 12 minutes in a maximal effort rowing ergometer test). Sailing performance was assessed by national coach ranking of each New Zealand sailor.On average the New Zealanders were younger and lighter than the sailors from the other nations. They tended to have greater shoulder/arm strength endurance as reflected in their performance for push-ups and pull-ups, but a lesser ability in their sit-up performance. They also tended to be aerobically fitter. There were clear and logical differences between body mass and both class of vessel and the position of the sailor i.c. crew or helmsman. Lighter sailors sailed lighter craft whilst heavier sailors sailed the heavier craft. Crew members were generally heavier than helmsmen. Age appeared to be related to sailing performance.Elite New Zealand Olympic class sailors tend to be younger, lighter, stronger and aerobically fitter than elite sailors from other nations. Age appeared to be related to on-water sailing performance.

Eleven healthy male volunteer soldiers (mean [SD] age 24.0 [2.8] years, stature 174.1 [5.2] cm, body weight 73.2 [10.8] kg, body fat 14.2 [5.0]% and maximal oxygen uptake 4.1 [0.4] 1 min-1) walked at 4.8 km h-1 on a motor driven treadmill for 5 min at each of three gradients (0, 2.5 and 5%) whilst carrying a two-part 26 kg load either on each shoulder or strapped to a backpack frame. The load was made up of two cylinders, one weighing 18.4 kg and the other weighing 7.6 kg. For all treadmill gradients the mean (SD) backpacking heart rates and oxygen uptakes (0% gradient, 122 [10] beats min-1, 1.51 [0.11] 1 min-1; 2.5% gradient, 135 [10] beats min-1, 1.81 [0.13] 1 min-1; 5% gradient, 155 [7] beats min-1, 2.21 [0.11] 1 min-1) were significantly (p less than 0.001) lower than for shoulder load carriage (0% gradient, 130 [9] beats min-1, 1.70 [0.12] 1 min-1, 2.5% gradient, 147 [8] beats min-1; 2.01 [0.10] 1 min-1; 5% gradient 164 [9] beats min-1, 2.39 [0.11] 1 min-1). The relative oxygen cost of backpacking was 4.3-4.7% VO2 max lower than for shoulder load carriage. It is concluded that the metabolic cost of backpacking an asymmetric two part 26 kg load was significantly less than for shoulder load carriage when walking at 4.8 km h-1 on a treadmill over gradients of 0-5%.(ABSTRACT TRUNCATED AT 250 WORDS)

Major scientific and clinical breakthroughs in HIV disease are rarely saved for the International Conference on AIDS. Nevertheless, this conference provides an opportunity for experts, providers, and patients to gain new information, exchange ideas, and assess progress. The Conference is also a public forum for political and social discussion and serves as a barometer of scientific and social trends as well. This year's conference featured refinements in clinical care, a deeper understanding of the epidemiologic trends, and a public awareness of the many political aspects of the AIDS epidemic. Contributions from family physicians and other primary care providers about problems they face and the family aspects of HIV need still greater prominence and exposure. Hopefully family physicians will use their expertise and report at future international conferences.

Cranial nuclear magnetic resonance (NMR) scans were performed on 13 healthy volunteers and 140 patients with a broad spectrum of neurologic disease and compared with x-ray computed tomography (CT) scans. The NMR scans included a variety of sequences reflecting proton density, blood flow, T1, and T2 as well as transverse, sagittal, and coronal images. White matter, gray matter, and cerebrospinal fluid were clearly distinguished in the normal brain with inversion-recovery (IR) sequences, and normal progressive myelination was demonstrated in infants and children. Acute hemorrhages displayed short T1 values, but other pathologic processes such as infarction, infection, demyelination, edema, and malignancy were associated with long T1 values. Cysts had very long T1 values (about that of cerebrospinal fluid). Spinecho (SE) sequences showed increased values of T2 in a variety of conditions and highlighted lesions against the relatively featureless background of the remaining brain. With inversion-recovery scans, different stages of infarction were recognized in the hemispheres. NMR was more useful than CT in demonstrating brainstem infarction. The white matter lesions in demyelinating diseases were well demonstrated with NMR scans. Many more lesions were observed in multiple sclerosis with NMR than with CT. Benign tumors were well seen and usually had shorter T1 values than malignant tumors. Mass effects from tumors were generally better demonstrated with NMR than with CT, including more subtle mass effects such as displacement of the external capsule. Abnormalities were seen in diseases of the basal ganglia, including marked atrophy of the head of the caudate nucleus in Huntington chorea. Advantages of NMR imaging include the high level of gray–white matter contrast, lack of bone artifact, variety of possible sequences, transverse, sagittal, and coronal imaging, sensitivity to pathologic change, and lack of known hazard. Disadvantages include lack of bone detail, limited spatial resolution, lack of contrast agent s, and cost. Promising directions for future clinical research include developmental neurology, tissue characterization with T1 and T2, assessment of blood flow, and the development of contrast agents. Much more detailed evaluation will be required, but NMR seems to be a potentially important addition to existing techniques of neurologic diagnosis.

In emergencies, it may be necessary for men to manually handle very large quantities of materials. Although data are available for loads carried on the back and there are specific civilian and military recommendations concerning safe maximum loads and acceptable workloads for repetitive lifting, data quantifying maximum capabilities for repetitive lifting tasks are not available. We have therefore undertaken a preliminary study to determine the relationship between lifting rate and time to exhaustion using three standard loads. Eight healthy, fit, well-trained young soldiers bimanually lifted three loads (25, 50 and 75% of their maximal lifting capacity (MLC) for a single lift to waist height) from the floor to a platform at waist height (40% stature) situated directly in front of them at lifting rates of 2, 3 and 4 lifts min −1 (75% MLC), 4, 6 and 8 lifts min−1 (50% MLC) and at 8, 10 and 12 lifts min−1 (25% MLC) for 1 hour or until they become exhausted or were unwilling or unable to continue or maintain...

Studies performed on 18 patients with Parkinson's disease and 6 control subjects have shown that acute administration of L-DOPA in clinically effective doses gives rise to a diffuse increase in regional cerebral blood flow without accompanying stimulation of regional oxygen utilization. The data suggest that this rise in rCBF is caused by vasodilatation due to a direct action of the drug on the cerebral blood vessels. The effect of L-DOPA on rCBF did not correlate with the degree of clinical improvement seen in each patient after treatment. The therapeutic effect of L-DOPA in the brain was not reflected in any change of regional cerebral oxygen utilization as measured by our technique. We suggest that the pharmacological actions of L-DOPA in the brain take place on at least two different levels.

This study was designed to investigate the cardiorespiratory, metabolic, and subjective responses to carrying a load close to the trunk in five different ways. Each of five subjects carried a load equivalent to 35% body weight (BW) for one hour at 4-5 km hr−1 and 0%grade on a motor driven treadmill using each of the following modes of load carriage: (1) the total load carried in a backpack with frame (BP/F), (2) the total load carried in a backpack with no frame (BP/NF), (3) half the load in a backpack (with frame) and half in pouches attached to a waist belt (BP/WB), (4) half the load in a backpack (with frame) and half in a front pack on the chest (BP/FP), and (5) the total load carried as a trunk jacket (TJ), i.e. a military type ‘flak’ jacket with weights inserted in pockets evenly distributed about the trunk. There were no statistically significant differences in the mean cardiorespiratory and metabolic costs associated with each of the five modes of load carriage. However, BP/FP and TJ were...

Observations are reported on six patients with inflammatory polyneuropathy who were treated by plasma exchange. In four cases the polyneuropathy was acute and in two it was chronic or relapsing. Two acute cases and one chronic relapsing case had plasma exchange during a rapidly progressive phase of the disease, and showed a prompt and substantial recovery of function. The other three patients were exchanged when disease activity had reached a plateau. Only minor degrees of improvement were seen in two of these cases. One patient showed an initial mild deterioration before subsequent recovery. There were no significant side effects. These findings are discussed in relation to the pathogenesis and clinical management of inflammatory polyneuropathy.

Human capabilities in manual materials-handling activities may be influenced by a number of task variables. The psychophysical method of Snook (1978) was used to determine the effects of load and lifting frequency upon workloads selected by eight male soldiers. The subjects repeatedly lifted and lowered a box (38 × 55 × 24 cm) to and from a platform set at 40% stature for 10 minutes and either adjusted the load, or the lifting frequency, or a combination of both variables in order to select a workload which they considered to be a maximum acceptable workload (MAWL) for a work-period of one hour. When the lifting frequency was adjusted, the mean MAWL was 94·5 kg m min −1 (S.D. 28·4). This was significantly greater (P ≤ 0·05) by 27% than when the load alone was adjusted (74·3 kg m min −1, S. D. 23·3). Control of both variables together produced a MAWL of 76·5 kg m min −1 (S. D. 24·1) which was similar to that selected when the load alone was adjusted. When the soldiers lifted and lowered their selected work...

Current physiological criteria for limiting work in hot conditions are frequently based on responses to mainly dynamic work (eg treadmill walking). Their applicability to industrial situations containing mixed static and dynamic work is questioned, since the physiological responses to static work are different from those of dynamic work. Each of eight subjects attempted a one hour uphill treadmill walk (mainly dynamic work), and an uphill treadmill walk whilst intermittently carrying a 20 kg weight in the arms (mixed static and dynamic work). The external work rates in the two conditions were equal, effected by lowering the treadmill gradient in the loaded condition. Experiments were conducted in a hot climate (33 degrees C dry bulb, 25 degrees C wet bulb). Oxygen consumption, minute ventilation, sweat rate and rated perceived exertion were all significantly higher (p less than 0.001) for the mixed static and dynamic work than for the dynamic work. This was also the case for heart rate and forearm skin temperature (p less than 0.01), and for auditory canal temperature (p less than 0.05). There was no significant difference between the two types of work for mean skin temperature, calf skin temperature and chest skin temperature. These results show that for the same external work, physiological strain and perceived exertion are greater for mixed static and dynamic work (carrying a load in the arms) than for mainly dynamic work (walking on a treadmill). They suggest that it is not appropriate to make direct comparisons of laboratory studies based on dynamic work, with practical situations containing mixed static and dynamic work in the heat.

A multi-stage, repetitive lifting maximal oxygen uptake ( $$\dot V_{O_{2max} }$$ ) test was developed to be used as an occupational research tool which would parallel standard ergometric $$\dot V_{O_{2max} }$$ testing procedures. The repetitive lifting $$\dot V_{O_{2max} }$$ test was administered to 18 men using an automatic repetitive lifting device. An intraclass reliability coefficient of 0.91 was obtained with data from repeated tests on seven subjects. Repetitive lifting $$\dot V_{O_{2max} }$$ test responses were compared to those for treadmill, cycle ergometer and arm crank ergometer. The mean±SD repetitive lifting $$\dot V_{O_{2max} }$$ of 3.20±0.42 l · min−1 was significantly (p

There are many different ways in which loads may be carried, and the mode of load carriage adopted can be determined by factors such as weight, shape and size of the load, the duration for which it has to be carried, the terrain, climate and the physical characteristics and condition of the individual and the clothing he wears as well as his personal preference. It is generally more expensive in terms of energy cost to carry loads on the head, in the hands or arms, or attached to the legs, than to carry the load closely attached to the trunk as when using a backpack. A combined front-and backpack, or carriage of loads around the waist, tend to incur the lowest energy cost for a given load, as lateral and anteroposterior stability is optimized. However, there may be chest restriction and a limitation to evaporate body cooling, and donning and doffing problems may mitigate against the adoption of this method. Hand or arm carriage usually leads to local muscle fatigue rather quickly. Despite this, for conven...

The psychophysical method used by Snook [576] to determine maximum acceptable workloads for repetitive lifting during an 8 hour workday in industrial populations was evaluated for application in military ergonomics. Under the conditions of the present experiment, the mean load selected by 10 soldiers (17-5 kg) was lower than reported by Snook [576] for industrial workers, and by Garg and Saxena [243] for college students. When the soldiers lifted and lowered their selected load for an 8 hour workday, the average heart rate was 92 beats min−1 and the mean oxygen cost was 21% of their maximum oxygen uptake (determined for uphill treadmill running). There was no evidence of cardiovascular, metabolic or subjective fatigue. The results indicate that with good subject co-operation and firm experimental control in a laboratory, the psychophysical method can identify loads that soldiers can lift repetitively for an 8 hour workday without metabolic, cardiovascular or subjective evidence of fatigue, but it is not c...

The sedative effects of single doses of hypnotic drugs in normals are still detectable on behavioural tests 13 hours after administration, and on the electroencephalogram (EEG) at 18 hours (Malpas et al., 1970), and similar results have been noted by other workers (Lader and Walters, 1971). Using measures of driving skill, Betts et al. (1972) have also found that normal subjects may be impaired after five doses of amylobarbitone sodium taken over the preceding 36 hours. However, the relevance of all these results to the prediction of effects in patients for whom the drugs are prescribed is uncertain, as our preliminary report indicated (Legg et al., 1973). Here we present the more detailed results of a study carried out on anxious out-patients, using behavioural and EEG measures to determine whether or not persistent effects were present following a course of 7 days treatment with hypnotic drugs.

In emergencies, it may be necessary for men to manually handle very large quantities of materials. Although data are available for loads carried on the back and there are specific civilian and military recommendations concerning safe maximum loads and acceptable workloads for repetitive lifting, data quantifying maximum capabilities for repetitive lifting tasks are not available. We have therefore undertaken a preliminary study to determine the relationship between lifting rate and time to exhaustion using three standard loads. Eight healthy fit, well-trained young soldiers bi-manually lifted 3 loads lpar;25, 50 and 75percnt; of their maximal lifting capacity (MLC) for a single lift to waist height) from the floor to a platform at waist height (40% stature) situated directly in front of them at lifting rates of 2,3 and 4 lifts min−1 (75% MLC), 4,6 and 8 lifts min−1 (50% MLC) and at 8,10 and 12 lifts min−1 (25% MLC) for one hour or until they became exhausted or were unwilling or unable to continue or main...

The rise in intra-abdominal pressure (IAP) during lifting reduces spinal stress by acting synergistically with the contraction of the extensor muscles of the spine. If the IAP does not rise during lifting it seems likely that there will be a greater risk of low back injury due to greater spinal instability. It is possible that abdominal muscle fatigue may prevent the development of an adequate IAP during lifting, thereby predisposing an individual to a low back injury. Strengthening of the abdominal muscles by training has been advocated as a way of reducing the likelihood of back injury. An experiment was conducted to investigate the effect of abdominal muscle fatigue and training on the intra-abdominal pressure during lifting. First, abdominal muscle fatigue was induced in six healthy young male subjects who performed ‘sit-ups’ repetitively to exhaustion, after which IAP was measured in a sub-maximal lifting test and compared with values obtained before the fatigue-inducing exercise. There was no statis...

Regional cerebral oxygen utilisation (rCMRO2), oxygen extraction (rOER), blood flow (rCBF), and blood volume (rCBV) have been determined for fifteen patients with multiple sclerosis in remission using positron emission tomography (PET). Cerebral oxygen utilisation and blood flow were significantly reduced in both white matter and peripheral cortical grey matter in the multiple sclerosis patients compared to a group of normal controls. No evidence of regional cerebral ischaemia in the multiple sclerosis group was found. Lowest levels of cerebral oxygen utilisation were found in patients with cerebral atrophy, and in patients in whom a significant fall in present full-scale IQ from estimated pre-morbid levels had occurred. No correlation was found between rCMRO2 values and severity of locomotor dysfunction or clinical disease duration.

The metabolic, cardiovascular and spinal strain of a representative fuel replenishment task for a tank crew were assessed using nine military subjects wearing coveralls in a comfortable ambient climate. The task involved lifting 5 gal jerry cans (weighing 23·4 kg) from the ground to a height representing a tank deck (1·676 m) at a rate of two lifts per minute for 15 min. Oxygen uptake ([Vdot]O2), minute ventilation ([Vdot]E), heart rate (HR) and intra-abdominal pressure (IAP) were monitored continuously. After 15 min of lifting the mean [Vdot]O2 was 0·821 min−1 (S.D. 0·18). This was 27% of the predicted [Vdot]O2 max. The mean [Vdot]E was 21·81 min−1 (S.D.4·1) and the HR was 111·3 beats min−1 (S.D. 17·8). The mean peak IAP was 105·6 mmHg, with 56% of the peak IAPs exceeding 90 Hg. The mean intrasubject coefficient of variation was 10·7% (range 7·2–24·2). In a separate series of 20 consecutive bimanual straight arm vertical lifts of 10 kg at 15 s intervals, the mean intrasubject COV% was 7·2% (range 3·2–11·...

An echo ultrasound technique for the measurement of the lumbar spinal canal has been assessed. Duplicate measurements of each lumbar vertebral level were made by one experienced technician on 50 healthy young males. The mean spinal canal measurement of 1.37 cm was approximately 0.2 cm less than previously reported. Seven subjects returned for reassessment. The within and between session coefficients of variation were 3.7% and 5.8%, respectively. In contrast to previous reports of three distinctly separate echoes, the authors found that the first two echoes seldom were separated clearly and most commonly formed a complex. It is concluded that if suitable interobserver and interlaboratory comparisons are made at an early stage, the reproducibility of the method is likely to be adequate for prospective epidemiologic studies.

Psychophysical methods have been used successfully to establish maximal acceptable loads (MALs) in industrial repetitive lifting tasks, and it is known that physical tasks remain relatively unaffected by sleep deprivation, whereas cognitive tasks may be significantly degraded. Since the psychophysical method is essentially a physical task yet has a cognitive element (in that subjects are required continuously to reassess their decisions concerning MAL based upon their perceptions of the load weight), it was not known whether MAL would remain unchanged or be degraded by sleep deprivation. Consequently, two groups of soldiers (a sleep-deprived and control group) were studied over a 3 week period. After 5 training days, a week-end and 2 baseline days, the sleep-deprived group were partially sleep deprived for 3 days and then totally sleep deprived for 2 days, whilst the control group were allowed 4 hours uninterrupted sleep daily. There followed 1 day during which the subjects were allowed to sleep ...

This study was designed to determine if post exercise recovery measurements could be used to predict oxygen uptake (VO2), minute ventilation (VE) and heart rates (HR) during exercise. VO2, VE and HR were measured in 11 healthy males during the last minute of treadmill running and during standing recovery. Since it is often impractical to collect data during the first 15 s of recovery in the field, the equations which best predicted the observed last-minute exercise values were obtained from enhanced linear least squares regressions of data collected between 15 and 60 s after cessation of exercise. In a separate validation experiment the mean (S.E.) difference between predicted and observed values for VO2, VE, and HR were 0.08 (0.06) L.min-1, 1.0 (5.1) L.min-1, and 2.2 (1.4) beats.min-1, respectively. We conclude that the equations described in this study may be used to estimate the metabolic cost of exercise in situations where it is impossible to make direct measurements.

The psychophysical method used by Snook (1978) to determine maximum acceptable workloads for repetitive lifting during an 8-hour work-day in industrial populations was evaluated for application in military ergonomics. Under the conditions ofthe present experiment, the mean load selected by 10 soldiers (17·5 kg) was lower than reported by Snook (1978) for industrial workers and by Garg and Saxena (1979) for college students. When the soldiers lifted and lowered their selected load for an 8-hour work-day, the average heart rate was 92 beats min−1 and the mean oxygen cost was 21% of their maximum oxygen uptake (determined for uphill treadmill running). There was no evidence of cardiovascular, metabolic or subjective fatigue. A subjective rating method tended to identify slightly lower loads than the psychophysical method. The results indicate that with good subject cooperation and firm experimental control in a laboratory, the psychophysical method can identify loads that soldiers can lift repetitively for a...

Previous studies have investigated the oxygen cost ([Vdot]02) of increasing boot weight during unloaded walking or running, and have shown that for each 100 g increase in weight of footwear there is a 0·7-1·0% increase in [Vdot]O2 In reality (except in athletic events) the use of heavy footwear is associated with load carriage, usually backpacking. We therefore investigated the effects of increasing boot weight by 5% of body weight on the [Vdot]02 of backpacking a load amounting to 35% of the body-weight in five healthy young males who walked at 4·5 km/hour (0% grade) on a motor-driven treadmill. The results indicated a mean increase of 0·96% in [Vdot]02 whilst backpacking for each 100thinsp;-g increase in boot weight. In contrast the oxygen cost of increasing the backpack load was only 0·15% indicating that it was 6·4 times more expensive to carry weight on the feet as compared to the back. It is concluded that the relation between boot weight and oxygen cost, previously developed for unloaded walking an...

In a military field artillery trial, the effects of 8 days of sustained manual work and partial sleep loss on isometric right hand grip strength and upper and lower body anaerobic power (using the Wingate test) was investigated in 25 healthy young male soldiers. During the trial, the physical activity of each subject was essentially identical except that an experimental group (n = 18) manually handled a large quantity of artillery shells (weighing 45 kg) and charges (13 kg), whilst a control group (n = 7) merely simulated manual handling activities and did no lifting or loading of shells. The daily amount of sleep obtained by each group was similar (3 to 4 hours), as were their activity patterns and food and fluid intake. Isometric right hand grip strength for both groups fell progressively during the trial and did not return to pre-trial levels during 3 days of recovery. At the end of the 8 day trial, there were statistically significant reductions in the body weight (1.9%, p less than 0.001), % body fat (7.1%, p less than 0.001) and upper body mean power (7.3%, p less than 0.01) of the experimental group but not in the controls. Lower body peak and mean power were significantly increased at the end of the trial in both the experimental (14.7%, p less than 0.001 and 17.0%, p less than 0.001 respectively) and control (14.3%, p less than 0.01 and 15.0%, p less than 0.05 respectively) groups. Lower body power decrease was significantly increased (18.1%, p less than 0.05) in the experimental group but not in the controls.(ABSTRACT TRUNCATED AT 250 WORDS)

Ten patients with multiple sclerosis (MS) were scanned by means of cranial X-ray computed tomography (CT) with and without intravenous contrast enhancement, and by nuclear magnetic resonance (NMR) using an inversion-recovery sequence. Altogether 19 lesions varying in size between about 7 mm X 5 mm and 13 mm X 8 mm were demonstrated by CT. They were all situated in the periventricular region. Two patients also showed moderate ventricular enlargement. In addition to these abnormalities 112 further lesions were demonstrated on the NMR scans. These lesions varied in size from 4 mm X 3 mm to 12 mm X 7 mm and were particularly well seen in the periventricular region and brainstem. Care is required in the assessment of NMR scans to exclude artefacts, background noise, and mottle as well as normally situated grey matter and partial volume effects from cerebral sulci. NMR nevertheless demonstrates abnormalities in MS on a scale not previously seen except at necropsy.