Oral contraceptive phase has no effect on endurance test.

Thirteen female cyclists/triathletes (mean peak VO(2) = 53.0 + 5.6 ml . kg (-1) . min (-1)) using a monophasic oral contraceptive (OC) performed an endurance test (1-h cycle) at three time points of an OC cycle. Testing times were during the OC consumption phase (CONS), early in the OC withdrawal phase (WITH1) and late in the OC withdrawal phase (WITH2). Resting endogenous serum oestradiol and progesterone concentrations were measured. Power output, heart rate (HR), ventilation (V(E)), oxygen consumption (VO(2)), respiratory exchange ratio (RER), rating of perceived exertion (RPE), blood lactate and blood glucose were measured throughout the 1-h test. Serum oestradiol levels were greater during WITH2 compared to the CONS (p < 0.05). No significant differences were present between the testing times for mean power output (172 - 173 watts), HR (163 - 166 bpm), VO(2) (41.3 - 41.7 mL . kg (-1) . min (-1)), RER (0.93 - 0.94), RPE (14.5 - 14.8) and blood glucose concentration (5.3 - 5.5 mmol . L (-1)) (p > 0.05). Greater mean V. (E) (by 3.4 and 5.7 L . min (-1)) and VE/VO(2) (by 1.0 and 2.0) values were measured during CONS compared to WITH1 and WITH2 respectively and blood lactate values (by 1.2 mmol . L (-1)) compared to WITH1 only (p < 0.05). Despite variation in some physiological variables, there was no difference in endurance performance throughout an OC cycle in endurance trained female athletes.

Time-motion analysis of elite field hockey during several games in succession: a tournament scenario.

International field hockey tournaments may require teams to play three games within a period of four days. Therefore, there is potential for residual fatigue to affect the movement patterns of players during subsequent games. The purpose of this study was to document changes in time-motion analysis of 14 elite male field hockey players during three games within a period of four days during an international tournament. In addition, the nature of and any changes in repeated-sprint activity were investigated using a criteria of a minimum of three sprints with a mean recovery duration between sprints of < 21 s. The percent of total game time spent standing significantly increased across all three games (7.4+/-.2, 11.2+/-2.7 and 15.6+/-5.6%, respectively, P<0.05). Conversely, the percent time spent jogging significantly decreased from game 1 to game 2 and from game 1 to game 3 (40.5+/-7.3, 34.8+/-7.4 and 29.4+/-5.7%, respectively, P<0.05). Furthermore, the percent time in striding significantly increased from game 1 to game 3 and from game 2 to game 3 (4.1+/-1.3, 5.1+/-0.9 and 5.8+/-1.4%, respectively. P<0.05). Changes in mean motion frequency and duration were recorded across games for the motions of standing, striding and sprinting. The frequency of exercise bouts that met the criteria for 'repeated-sprint' decreased across the three games (17, 11 and 8, respectively). In summary, the results suggest that when elite field hockey players play three games within four days there are significant changes in time-motion analysis.

A multistage shuttle swim test to assess aerobic fitness in competitive water polo players.

A 10m multistage shuttle swim test (MSST) was designed for the assessment of aerobic fitness of competitive water polo players. Test-retest reliability was determined using a sample of 22 female and 22 male trained water polo players. An intraclass correlation coefficient of 0.99 (p>0.05) was calculated between the two test scores. The technical error of measurement for the test was 2.3 shuttles or 5.0%. The validity of the test was determined using a sample of 13 female and 12 male water polo players. A validation correlation coefficient of 0.88 resulted between the number of shuttles completed during the MSST and VO2max [litres/body surface area/ minute (l x BSA-1 x min-1)] measured during an incremental tethered swim test to exhaustion. A stepwise multiple regression revealed that VO2max (l x BSA-1 x min-1) accounted for approximately 78% of the MSST variance. It was concluded that the 10m multistage shuttle swim test is a reliable and valid field test of aerobic fitness for use with trained water polo players.

The role of class I and class II HLA antigens in primary open angle glaucoma (POAG).

Several clinical and epidemiological studies have shown the role of genetic factors in the pathogenesis of primary open angle glaucoma (POAG). In this study, 30 patients affected by this disease were tissue-typed for HLA Class I and Class II antigens. The results pointed up an increased incidence of some antigens and, particularly, a statistically significant association with DQ1 and DR11 alleles.

Psoriatic arthritis or overlap syndrome.

In this work we describe a case of papillophlebitis type II according to Hayreh in a young woman affected by psoriatic arthritis. On the basis of an analysis of the patient's HLA system--B7, DR7 (characteristics of psoriatic arthritis) and B51 (present in 81% of patients affected by Behçet's syndrome)--we hypothesize that this may be a case of an 'overlap syndrome'. In rheumatology, this term usually refers to the presence in a single patient of characteristic features of two or more diseases. In fact, papillophlebitis is a complication which has never been described in psoriatic arthritis, while, in Behçet's syndrome, retinal vasculitis is well known.

VDU work: longitudinal survey on refractive defects.

A longitudinal survey in two different phases with an interval of 4 years (including more than 23,000 employees) has been carried out to study whether the time spent using VDU (daily hours and years of work) can change the refractive state. With reference to the whole sample including all refractions, there was no significant difference in the refractive state in employees who spent varying daily hours or years working at VDU. Furthermore, there were no significant changes in the refractive states of emmetropic, hypermetropic and myopic subjects, with regard to the time spent working at VDU. The data have shown that a high exposure to VDU work (more than 6 h per day or more than 6 years spent working at a VDU) is not responsible for inducing or worsening refractive error.

Trends regarding myopia in video terminal operators.

A longitudinal study with a 4-year follow-up was carried out on 6101 employees of the Italian Telecommunications Company (Telecom Italia) to study the role of work at Video Display Units (VDU) for the evolution of different types of myopia (mild, intermediate and pathologic). The refractive modifications of myopic VDU operators were further studied with regard to differences in time of use of VDU (daily hours and years spent working at a VDU). No statistically significant difference was found for refractive modifications, neither with regard to the type of myopia, nor to the daily hours and years spent working at a VDU. The results have indicated that the use of VDU is not responsible for a worsening of myopia.

Psychology of computer use: XXXVI. Visual discomfort and different types of work at videodisplay terminals.

The relationship between visual discomfort (or asthenopia) and different types of work using display units for 10,626 videodisplay terminal operators of the Italian Telecommunication Company was studied. Visual discomfort was evaluated as related to data entry, data checking, word processing, dialogue, enquiry, and various services. Chi-squared indicated that visual discomfort was not significantly related to any particular type of work for subjects with similar amounts of weekly time using videodisplay units. These findings are consistent with earlier results indicating that the main factor determining visual fatigue in VDT operators is the amount of time spent on the display units.

Protective filters in the prevention of asthenopia at a video display terminal.

In this work 25,064 employees were studied with the aim of investigating whether the video display terminal (VDT) equipped with filters reduces the incidence of asthenopia with reference to weekly time spent at a VDT and duration of work at a VDT. Analysis showed that the filters themselves do not reduce the occurrence of asthenopia consequent to various factors (refractive defects, time spent at a VDT, and monitors' characteristics).

Is the type of VDT work important in asthenopia?

The Authors studied the relationship between visual fatigue (or asthenopia) and different types of work with display units on about 30,000 videoterminal (VDT) operators of the Italian telecommunication company. Visual fatigue was reported with data entry, data checking, word processing, dialogue enquiry, and various services. The Chi-square test showed that asthenopia was not related to any particular type of VDT work, comparing subjects working at the VDT for similar times each week. These findings provide further confirmation that the main factor determining visual fatigue in VDT operators is the amount of time spent at the display units.

Natural versus haploscopic stereopsis.

Natural stereopsis is better with a large interpupillary distance (IPD). With haploscopic devices, depth perception is better with a small IPD. This apparently unknown fact has been trigonometrically calculated and experimentally shown by enlarging and diminishing the IPD in 20 subjects.

[Asthenopia and monitor characteristics]. / Asthénopie et écran de visualisation.

An epidemiological survey on 30,000VDT operators has been carried out to evaluate the relationship between asthenopia and monitor characteristics. A VDU operator has been classified as asthenopeic if he complained about at least two of the following ten symptoms: headache, tearing, eye smarting, blurred vision, double vision, ocular itching, photophobia, blinking, nausea, eye heaviness. Visual discomfort has been related to 1) the presence of flicker; the possibility to regulate, 2) brightness, 3) height; and 4) inclination of monitor. Asthenopia has resulted statistically correlated to the presence of flicker and to the impossibility of regulating height and inclination of monitor for both sexes. The possibility to regulate monitor brightness has not determined a reduction of visual discomfort either in men or in women.

The clinical significance of the reduced capillary resistance factor in the diabetic patient.

A statistical survey in a group of 235 subjects (174 diabetic patients and 61 nondiabetic control subjects) was conducted to evaluate the incidence of reduced capillary resistance factor in respect to diabetic disease, to its duration, and to the severity of retinopathy. To evaluate the capillary resistance we used a cupping-glass method (Parrot's angiosterrometer test). The incidence of reduced capillary resistance proved to increase in frequency with diabetes, with its duration, and with the severity of retinopathy. Thus, reduced capillary resistance represents a negative prognostic element for retinopathy.