[Dietary iron intake and deficiency in elite women volleyball players]

INTRODUCTION

Volleyball practice requires repeated impacts on arms and feet caused by vertical jumps, falls, auctions, sudden and rapid changes of direction, which is why might raise us problems in the metabolism of iron (Fe) and the recommended intake of 18 mg/day (in the women in general), is not sufficient to meet the needs of the players of volleyball female (JVF).

OBJECTIVE

We analyzed the FS and IST of 10 JVF a team of Spanish SuperLeague (26.6 ± 5.9 years and height 178.05 ± 8.7 cm) in two moments of the season: Week 0 (pre-start of preseason) and week 11 (after 11 weeks of training and 6 games of the regular season). Also calculated Fe intake in this period with consumption frequency questionnaire developed and tested with food dietary records of 7 days.

RESULTS

We observed that an intake of 25.8 mg/day of dietary Fe is not sufficient to prevent 30% of the JVF suffer pre-latent iron deficiency and 20% latent deficit (pre-anemia).

CONCLUSION

It could be recommended conducting periodic blood analytical and a food education, teaching which foods containing a high content of Fe-type heme, and the factors that can interfere with absorption.

Changes induced by diet and nutritional intake in the lipid profile of female professional volleyball players after 11 weeks of training

Background

The relationship between cardiovascular disease and lipid profile is well known. Apart from a heart-healthy diet, exercise is the primary factor that can modify this lipid-associated cardiovascular risk. The aim of the study was to evaluate potential changes in the levels of triglycerides, total cholesterol (TC), low-density lipoprotein-cholesterol (LDLc), and high-density lipoprotein-cholesterol (HDLc), as well as atherogenic indices (TC/HDLc and LDLc/HDLc), and also to analyse the diet over 11 weeks of training in female professional volleyball players.

Methods

The lipid profile of 22 female professional volleyball players was analysed on Day T0 (pre-preseason) and Day T11 (after 11 weeks of training). The consumption of fats by the players was estimated using a food frequency questionnaire, confirmed by seven days of full dietary records.

Results

By the end of the study, the LDLc levels and both atherogenic indices of the players had decreased (p < 0.05) compared to the values obtained at baseline. In addition, the diet of the players contained 35.5 ± 3.2% of fats (saturated fatty acid: 11.1 ± 1.2%, monounsaturated fatty acid: 14.3 ± 1.9%, and polyunsaturated fatty acid: 7.0 ± 1.1%) and 465 ± 57 mg of dietary cholesterol. Their score for the (monounsaturated + polyunsaturated fatty acid)/saturated fatty acid ratio was 1.9 ± 0.4, less than the recommended ≥ 2.

Conclusion

These data indicate that the activity of the female professional volleyball players during the first 11 weeks of training in the season was heart healthy, because their lipid profile improved, despite an inadequate intake of fats.

Análisis nutricional de la ingesta dietética realizada por jugadoras de voleibol profesional durante la fase competitiva de la liga regular

Introducción: los aspectos nutricionales del voleibol femenino han sido poco estudiados y más en un periodo específico de entrenamiento como el periodo competitivo. El objetivo es valorar y conocer la ingesta calórica y de macronutrientes realizada por jugadoras de voleibol profesional de la superliga española durante 16 semanas de entrenamiento correspondientes a la fase competitiva y compararlas con las referencias marcadas para la población deportista.Material y Métodos: se analizó a 10 jugadoras de voleibol femenino (JVF) (26,6±5,9 años y talla 178,05±8,7cm), durante un total de 16 semanas de entrenamiento y competición correspondiente a la fase competitiva. Todas ellas firmaron el consentimiento informado. Todasrellenaron un cuestionario de frecuencia de consumo de alimentos (CFCA) de las 16 semanas del estudio, datos corroborados mediante un registro dietético de 7 días consecutivos, en la semana 9 y 16. Se calculó la ingesta de nutrientes diaria a partir de los datos del CFCA utilizando la tabla de composición de alimentos del CESNID, mediante el software Easy Diet, de la Asociación Española de Dietistas-Nutricionistas (AEDN).Resultados: el análisis energético-nutricional realizado a las jugadoras profesionales de voleibol muestra que la cantidad de energía y de los macronutrientes no se ajusta a las recomendaciones para el colectivo deportivo. Se observa una ingesta energética y de hidratos de carbono baja y una ingesta demasiado elevada en proteínas y lípidos.Conclusiones: se recomiendan aspectos prácticos para la mejora de la educación alimentaria en este grupo deportivo profesional.

A long-term physical activity training program increases strength and flexibility, and improves balance in older adults

PURPOSE

Physical activity training programs in older adults have recognized health benefits. Evidence suggests that training should include a combination of progressive resistance, balance, and functional training. Our aim was to assess the effects of a simple physical activity program working on strength, flexibility, cardiovascular fitness, and balance in older adults, as well as the effects of a detraining period, at various different ages.

METHODS

This was longitudinal prospective study, including a convenience sample of 227 independent older adults (54 men, 173 women) who completed a simple 9-month training program and 3-month detraining follow-up. The subjects were categorized into two age groups (65-74 [n = 180], and >74 years [n = 47]). At the beginning of the study (baseline), the end of the training period, and 3 months later (postdetraining), body mass index, body fat percentage, triceps skinfold thickness, hand grip strength, lower limb and trunk flexibility, resting heart rate, heart rate after exercise, and balance were measured, while VO(2 max) was estimated using the Rockport fitness test and/or measured directly.

RESULTS

Significant improvements in strength (p < .0001), flexibility (p < .0001), heart rate after exercise (p < .0001), and balance (p < .0001) were observed at the end of the training program. Flexibility and balance (p < .0001) improvements were maintained at the end of the detraining.

CONCLUSION

A simple long-term physical activity training program increases strength in both sexes, improves flexibility in women, and improves balance in older adults. The results also indicate the importance of beginning early in old age and maintaining long-term training.

Adaptive response in the antioxidant defence system in the course and outcome in first-episode schizophrenia patients: a 12-months follow-up study

Correlation of plasma antioxidant enzyme activity with the course and outcome in first-episode schizophrenia patients (n=49) was analyzed in order to assess the possible utility of peripheral markers of oxidative stress as prognostic factors. These markers were measured shortly after the onset of schizophrenia, and again 1, 6 and 12 months later. A decrease in catalase (CAT), glutathione peroxidase (GPx), superoxide dismutase (SOD), and glutathione (GSH) levels and total antioxidant status (TAS), as well as an increase in thiobarbituric acid reactive substances (TBARS), were observed 1 month after (p<0.05). 6-Months later, there was a reduction in TAS, GSH, SOD and GPx, and a increase in TBARS (p<0.05), with a normalization of CAT levels, indicating a persistent alteration of the antioxidant system and the maintenance of oxidative stress. At 12-months, a considerable decrease was observed in TBARS. Additionally, while the level of GPx decreased (p<0.05) further, SOD and GSH levels and TAS were normalizing, indicating a partial regeneration of the antioxidant defence system. These results indicate the possible contribution of oxidative stress to the onset and pathophysiology of schizophrenia, suggesting the involvement of an adaptive response in the antioxidant defence system in the course and outcome in first-episode schizophrenia patients.

Predicting the evolution of low back pain patients in routine clinical practice: results from a registry within the Spanish National Health Service

BACKGROUND CONTEXT

The Spanish National Health Service (SNHS) is a tax-funded public organization that provides free health care to every resident in Spain.

PURPOSE

To develop models for predicting the evolution of low back pain (LBP) in routine clinical practice within SNHS.

STUDY DESIGN

Analysis of a prospective registry in routine clinical practice, in 17 centers across SNHS.

PATIENT SAMPLE

Patient sample includes 4,477 acute and chronic LBP patients treated in primary and hospital care.

OUTCOME MEASURES

Pain and disability, measured through validated instruments.

METHODS

Patients treated for LBP were assessed at baseline and 3 months later. Data gathered were the following: sex, age, employment status, duration of pain, severity of LBP, pain down to the leg (LP) and disability, history of lumbar surgery, diagnostic procedures undertaken, imaging findings, and treatments used throughout the study period. Three separate multivariate logistic regression models were developed for predicting a clinically relevant improvement in LBP, LP, and disability at 3 months.

RESULTS

In total, 4,261 patients (95.2%) attended follow-up. For all the models, calibration was reasonable and the area under the receiver operating characteristic curve was ≥0.640. For LBP, LP, and disability, factors associated with a higher probability of improvement at 3 months were the following: not having undergone lumbar surgery, higher baseline scores for the corresponding variable, lower ones for the rest, and being treated with neuroreflexotherapy. Additional factors were the following: for LBP, shorter pain duration; for LP, not undergoing electromyography; and for disability, shorter pain duration, not being diagnosed with disc degeneration, and being treated with muscle relaxants and not opioids.

CONCLUSIONS

A prospective registry can be used for developing predictive models to quantify the odds that a given LBP patient will experience a clinically relevant improvement. This may empower patients for an informed shared decision making.

SU-E-I-111: Evaluation of the Analytical Scattering Models of 1) Lynch-Dahl 2) Highland and 3) Rossi for Proton Beams and Comparison with GEANT4 Monte Carlo Simulations as a Prerequisite for Proton Radiography Applications for Patients

PURPOSE

To evaluate the approximate 1) Lynch-Dahl 2) Highland and 3) Rossi scattering models for proton beams with GEANT4 Monte Carlo. This is a prerequisite for proton radiography applications for patients.

METHODS

A Matlab program developed in-house at MGH was used to obtain a semianalytical generalized Fermi-Eyges theory estimation of the spatial and angular spreads of a 230 MeV zero-spread incident proton beam as a function of depth. The constants of 1) Lynch-Dahl 2) Highland and 3) Rossi were used respectively for each model. MC simulations will determine which approximation provides the best prediction for different media configurations. Further, the calculated spreads were used to inform proton radiography imaging by calculating two limiting angles, a positional Acut and a directional Ccut. Acut is defined as the viewing angle of a point of incidence observer at which they see a point displaced by one positional standard deviation. Ccut is defined as the direction cosine of one angular standard deviation momenta.

RESULTS

Both the angular and spatial spreads as well as their respective model differences rose monotonically with depth in water. At 30 cm depth the angular spread reached values around 3 degrees with about 0.32 degrees model difference, translating to Ccut differences in the first or second significant digit. At the same depth the spatial spread reached values around 1.2 cm with about 0.7 mm model difference, translating to Acut differences in the first or second significant digit. Preliminary MC data (not shown) indicate that the signals obtained due to the influence of inhomogeneities are small and the model differences may be relevant.

CONCLUSIONS

We observed non-negligible differences between the models using MC. Further analysis is required to understand, which model provides most accurate scattering predictions for protons penetrating different media configurations.

SU-E-I-97: Characterizing the Modulation Transfer Function (MTF) of Proton Radiography

PURPOSE

To characterize the modulation transfer function (MTF) of proton radiography using GEANT4 Monte Carlo simulations.

METHODS

A phantom was specifically modeled using five main materials: bone (1.92 g/cm³ ), muscle (1.2 g/cm³ ), water (1.0 g/cm³ ), adipose tissue (0.9 g/cm³ ), and lung (0.3 g/cm³ ). The basic geometry of the phantom consists of cube-shaped inserts of biological materials placed in water. The thickness of the water, the size of the cube, the depth of the cube in the water, and the proton beam energy have all been varied and studied. The contrast-to-noise ratio (CNR) between the two materials was evaluated at multiple points along a line-of-interest (LOI) in order to ultimately characterize the spatial resolution by the 10% point of the modulation-transfer-function (MTF10% or MTF 10).

RESULTS

The MTF was generated for interfaces of water-lung, water-bone, water-muscle, water-adipose. This study indicates that proton radiography can distinguish one material from another with a resolution better than 1 mm for water-adipose and water-muscle or sub-millimeter in cases of water-bone and water-lung interfaces.

CONCLUSIONS

The sub-millimeter resolution of proton radiography offers clinicians a potentially tool in specific tumor diagnostics (such as in lung cancer), patient-setup for daily proton therapy, and the reduction of absorbed dose delivered when compared to photon imaging.

A modification of flattening filter free linac for IMRT

PURPOSE

This study investigates the benefits of a modified flattening filter free (FFF) linac over the standard (STD) linac equipped with the flattening filter. Energy and angular spread of the electron beam of the FFF linac were modified. Modification of FFF beam parameters is explored to maximize the monitor unit efficiency and to minimize the head scatter in IMRT delivery for large target volumes or targets lying away from the central axis.

METHODS

The EGSnrc code is used to model FFF and STD linacs and study basic beam properties for both linac types in various beam configurations. Increasing energy of FFF linac results in similar beam attenuation properties and maximized dose rate compared to STD linac. Matching beam attenuation properties allows a more direct exploration of beam flatness of FFF linac in regard to IMRT delivery, especially away from the central axis where the effective dose rate is considerably smaller than the one at the central axis. Flatness of open beam dose profile of FFF linac is improved by increasing the angular spread of the electron beam. The resulting dose rate within the treatment field and outside of the field (peripheral dose) are characterized and compared to the unmodified FFF and STD linacs,

RESULTS

In order to match beam penetration properties, the energy of FFF is adjusted from 6.5 to 8.0 MeV for small to medium field sizes and from 6.5 to 8.5 MeV for larger ones. Dose rate of FFF vs STD linac increased by a factor of 1.9 (6.5 MeV) and 3.4-4.1 (8.0-8.5 MeV). Adjusting the mean angular spread of the electron beam from 0 degrees to 5 degrees-10 degrees resulted in complete flattening of photon beam for field sizes between 10 x 10 cm2 and 15 x 15 cm2 and partial flattening for field sizes from 15 x 15 cm2 to 30 x 30 cm2. Values of angular spread > or =14 degrees are not recommended as they exceed the opening of the primary collimator, affecting the area at the edges of the field. FFF fields of sizes smaller than 6 x 6 cm2 are already flat and beam flattening is not necessary. Overall, the angular spread of 5 degrees-10 degrees is sufficient and can satisfactorily flatten open beam dose profiles even for larger field sizes. Increasing the electron beam angular spread amounts to a slight decrease of dose rate of FFF linac. However, for angular spread, 5 degrees-10 degrees dose rate factor of FFF vs STD is still about 1.6-2.6, depending on the field size (and the adjusted energy). Similarly, in case of peripheral dose, a moderate increase in dose can be observed for angular spread of 5 degrees-10 degrees and for field sizes 10 x 10 cm2 to 30 x 30 cm2. Lastly, beam flatness of not modified FFF linac can be conveniently described by an analytical function representing a ratio of STD vs FFF doses: 1 + b|r|(n).

CONCLUSIONS

A modified FFF beamline with increased energy and electron beam angular spread results in satisfactory flattened beam and high dose rate within the field. Peripheral dose remaining at similar (or smaller) level than that of STD linac for the same delivered dose within the treatment field.

Comparative study of a low-Z cone-beam computed tomography system

Computed tomography images have been acquired using an experimental (low atomic number (Z) insert) megavoltage cone-beam imaging system. These images have been compared with standard megavoltage and kilovoltage imaging systems. The experimental system requires a simple modification to the 4 MeV electron beam from an Elekta Precise linac. Low-energy photons are produced in the standard medium-Z electron window and a low-Z carbon electron absorber located after the window. The carbon electron absorber produces photons as well as ensuring that all remaining electrons from the source are removed. A detector sensitive to diagnostic x-ray energies is also employed. Quantitative assessment of cone-beam computed tomography (CBCT) contrast shows that the low-Z imaging system is an order of magnitude or more superior to a standard 6 MV imaging system. CBCT data with the same contrast-to-noise ratio as a kilovoltage imaging system (0.15 cGy) can be obtained in doses of 11 and 244 cGy for the experimental and standard 6 MV systems, respectively. Whilst these doses are high for everyday imaging, qualitative images indicate that kilovoltage like images suitable for patient positioning can be acquired in radiation doses of 1-8 cGy with the experimental low-Z system.