Relationship of physical activity to eating behaviors and weight loss in women

PURPOSE: To examine whether change in physical activity is associated with compliance to changes in dietary intake and eating behaviors in an 18-month behavioral weight loss program, and to examine the contribution of exercise to weight loss when these other weight loss behaviors are also considered. METHODS: Data from 104 subjects who completed an 18-month behavioral weight loss program were analyzed in this study. All subjects were prescribed a reduced energy (1,200-1,500 kcal x d(-1)) and fat (20 to 30%) diet, and exercise progressed from 100 to 200 min x wk(-1). Subjects attended group behavioral lessons throughout the study. Weight, physical activity, energy intake, and weight loss eating behaviors were assessed at 0 and 18 months. RESULTS: Body weight decreased 7.8 +/- 7.5 kg and body mass index decreased 2.8 +/- 2.7 kg x m(-2) from 0 to 18 months ( < 0.05). Total energy intake (kcal x d(-1)) and macronutrient intake (g x d(-1)) decreased, whereas physical activity and eating behaviors associated with weight loss increased from 0 to 18 months ( < 0.05). Change in physical activity was significantly correlated with weight loss (r = 0.33), reductions in energy intake (r = 0.20), and improvements in eating behaviors associated with weight loss (r = 0.24) ( < 0.05). Regression analysis indicated that change in physical activity significantly improved weight loss after changes in energy intake and weight loss eating behaviors were considered in the analysis, with R(2)significantly improving by approximately 0.04 ( < 0.05). However, results from multiple regression showed weight loss was influence more by changes in eating behaviors than changes in physical activity (R(2) = 0.17 vs R(2) = 0.04). CONCLUSIONS: The combination of changes in eating and physical activity behaviors can improve long-term weight loss compared with either behavior alone. Interventions targeting both behaviors are recommended for improving long-term weight loss.     

Vascular anomalies: what they are, how to diagnose them, and how to treat them

Vascular anomalies are congenital lesions that most often first present in pediatric patients. Treatment of these lesions is a multidisciplinary team approach, involving several specialties, including diagnostic and interventional radiology, dermatology, general and plastic surgery, otolaryngology, and hematology. Knowing the characteristic findings of vascular anomalies on ultrasound, computed tomography, and magnetic resonance imaging leads to early, accurate diagnosis and therapeutic intervention of these lesions. This article discusses the gross and radiographic appearances and the latest treatment options for vascular anomalies.     

Exercise and diet, independent of weight loss, improve cardiometabolic risk profile in overweight and obese individuals

Diet and/or exercise are routinely advised as methods for weight loss in overweight/obese individuals, particularly those who are at high risk for cardiovascular disease and type 2 diabetes mellitus. However, physical activity and structured exercise programs rarely result in significant loss of body weight or body fat, and weight-loss diets have extraordinarily high recidivism rates. Despite only modest effects on body weight, exercise and ad libitum nutrient-dense diets for overweight/obese individuals have many health benefits, including skeletal muscle adaptations that improve fat and glucose metabolism, and insulin action; enhance endothelial function; have favorable changes in blood lipids, lipoproteins, and hemostatic factors; and reduce blood pressure, postprandial lipemia and glycemia, and proinflammatory markers. These lifestyle-induced adaptations occur independently of changes in body weight or body fat. Thus, overweight/obese men and women who are at increased risk for cardiovascular disease and type 2 diabetes as a result of sedentary lifestyle, poor diet, and excess body weight should be encouraged to engage in regular physical activity and improve their diet, regardless of whether the healthier lifestyle leads to weight loss.     

Exercise responses prior to pregnancy and in the postpartum state.

Increased women in the work force and requirements for maximal employee productivity have necessitated examination of the optimal time for parturients to resume normal activities. This prospective study was designed to determine whether prepregnancy measures of aerobic capacity are regained by 4-8 wk postpartum. Weight, percent body fat, recall energy expenditure, and exercise responses via a stage 1, graded cycle ergometer exercise test were determined in 11 subjects (mean age = 27.56 +/- 2.2) in a postabsorptive state prior to pregnancy and 4-8 wk postpartum. Subject characteristics were compared by the Student's t-test and differences across workloads and time by analysis of variance with repeated measures. Prepregnant weight (mean = 58.80 +/- 7.26 kg) was significantly less (P less than 0.05) than postpartum weight (mean = 62.81 +/- 9.12 kg), and prepregnant energy expenditure (1352 +/- 453 kJ) per day was significantly higher (P less than 0.05) than in the postpartum period (274 +/- 333 kJ). Maximal oxygen uptake was significantly higher (35.2 +/- 0.7 vs 30.5 +/- 2.0 ml.kg-1min-1) in the prepregnant as compared with the postpartum period. Further, heart rate at 125 and 150 W was significantly lower prepregnancy as compared with postpregnancy. Results support a detraining effect in the early postpartum period. Whether this detraining is an inevitable factor associated with pregnancy or whether exercising throughout pregnancy can ameliorate the decline in aerobic capacity postpartum is uncertain.     

Medical and surgical devices in the emergency and trauma patient: what the radiologist should know,and how they can add value

A variety of different external and internal medical devices are used in the acute setting to maintain life support and manage severely injured and unstable trauma or emergency patients. These devices are inserted into the acutely ill patient with the specific purpose of improving outcome, but misplacement can cause additional morbidity and mortality. Consequently, meaningful interpretation of the position of devices can affect acute management. Some devices such as nasopharyngeal, nasogastric and endotracheal tubes and chest and surgical drains are well known to most clinicians, however, little formal training exists for radiologists in composing their report on the imaging of these devices. The novice radiologist often relies on tips and phrases handed down in an aural tradition or resorts to phrases such as: “position as shown”. Furthermore, radiologists with limited experience in trauma might not be familiar with the radiological appearance of other more specific devices. This review will focus on the most common medical devices used in acute trauma patients, indications, radiological appearance and their correct and suboptimal positioning.     

Radiation dose exposure in patients affected by lymphoma undergoing repeat CT examinations: how to manage the radiation dose variability

Purpose

To assess the variability of radiation dose exposure in patients affected by lymphoma undergoing repeat CT (computed tomography) examinations and to evaluate the influence of different scan parameters on the overall radiation dose.

Materials and methods

A series of 34 patients (12 men and 22 women with a median age of 34.4 years) with lymphoma, after the initial staging CT underwent repeat follow-up CT examinations. For each patient and each repeat examination, age, sex, use of AEC system (Automated Exposure Control, i.e. current modulation), scan length, kV value, number of acquired scans (i.e. number of phases), abdominal size diameter and dose length product (DLP) were recorded. The radiation dose of just one venous phase was singled out from the DLP of the entire examination. All scan data were retrieved by our PACS (Picture Archiving and Communication System) by means of a dose monitoring software.

Results

Among the variables we considered, no significant difference of radiation dose was observed among patients of different ages nor concerning tube voltage. On the contrary the dose delivered to the patients varied depending on sex, scan length and usage of AEC. No significant difference was observed depending on the behaviour of technologists, while radiologists’ choices had indirectly an impact on the radiation dose due to the different number of scans requested by each of them.

Conclusions

Our results demonstrate that patients affected by lymphoma who undergo repeat whole body CT scanning may receive unnecessary overexposure. We quantified and analyzed the most relevant variables in order to provide a useful tool to manage properly CT dose variability, estimating the amount of additional radiation dose for every single significant variable. Additional scans, incorrect scan length and incorrect usage of AEC system are the most relevant cause of patient radiation exposure.

     

Facing the future: the effects of the impending financial drought on NHS finances and how UK radiology services can contribute to expected efficiency savings

The recent turmoil within the banking sector has led to the development of the most significant recession since the "great depression" of the 1930s. Although the coalition government has promised to "guarantee that health spending increases in real terms in each year of Parliament", this may still not be enough to meet future needs over the coming years due to increasing demand and cost pressures. The expected mismatch between actual National Health Service (NHS) funding post-2011 and that required to satisfy increasing demand has been estimated by the Department of Health to require efficiency savings representing up to one-fifth of the overall NHS budget. This paper explains the reasons behind the anticipated slowdown in the growth of real NHS funding, and how, as a discipline, radiology can increase the efficiency of the services it provides in anticipation of future financial austerity within the NHS.     

MR imaging features of high-grade gliomas in murine models: how they compare with human disease, reflect tumor biology, and play a role in preclinical trials

Murine models are the most commonly used and best investigated among the animal models of HGG. They constitute an important weapon in the development and testing of new anticancer drugs and have long been used in preclinical trials. Neuroimaging methods, particularly MR imaging, offer important advantages for the evaluation of treatment response: shorter and more reliable treatment end points and insight on tumor biology and physiology through the use of functional imaging DWI, PWI, BOLD, and MR spectroscopy. This functional information has been progressively consolidated as a surrogate marker of tumor biology and genetics and may play a pivotal role in the assessment of specifically targeted drugs, both in clinical and preclinical trials. The purpose of this Research Perspectives was to compile, summarize, and critically assess the available information on the neuroimaging features of different murine models of HGGs, and explain how these correlate with human disease and reflect tumor biology.     

Exercise heat acclimation and post-exercise hot water immersion improve resting and exercise responses to heat stress in the elderly

ObjectivesTo investigate the efficacy of heat acclimation (HA) in the young (Y_EX) and elderly (E_EX) following exercise-HA, and the elderly utilising post-exercise hot water immersion HA (E_HWI).DesignCross-sectional study.MethodTwenty-six participants (Y_EX: n = 11 aged 22 ± 2 years, E_EX: n = 8 aged 68 ± 3 years, E_HWI: n = 7 aged 73 ± 3 years) completed two pre-/post-tests, separated by five intervention days. Y_EX and E_EX exercised in hot conditions to raise rectal temperature (T_rec) ≥38.5 °C within 60 min, with this increase maintained for a further 60 min. E_HWI completed 30 min of cycling in temperate conditions, then 30 min of HWI (40 °C), followed by 30 min seated blanket wrap. Pre- and post-testing comprised 30 min rest, followed by 30 min of cycling exercise (3.5 W·kg⁻¹ Ḣ_prod), and a six-minute walk test (6MWT), all in 35 °C, 50% RH.ResultsThe HA protocols did not elicit different mean heart rate (HR), T_rec, and duration T_rec ≥ 38.5 °C (p > 0.05) between Y_EX, E_EX, and E_HWI groups. Resting T_rec, peak skin temperature, systolic and mean arterial pressure, perceived exertion and thermal sensation decreased, and 6MWT distance increased pre- to post-HA (p < 0.05), with no difference between groups. Y_EX also demonstrated a reduction in resting HR (p < 0.05). No change was observed in peak T_rec or HR, vascular conductance, sweat rate, or thermal comfort in any group (p > 0.05).ConclusionsIrrespective of age or intervention, HA induced thermoregulatory, perceptual and exercise performance improvements. Both exercise-HA (E_EX), and post-exercise HWI (E_HWI) are considered viable interventions to prepare the elderly for heat stress.     

Exercise immunology: future directions for research related to athletes, nutrition, and the elderly

This article examines three questions related to exercise immunology: 1) Can exercise attenuate changes in the immune system related to aging? The few research papers available suggest that the answer may be "yes", but exercise training may have to be long-term and of sufficient volume to induce changes in body weight and fitness before any change in immunity can be expected in old age. 2) Is the athlete an immunocompromised host? For most athletes, probably not, although the answer may be 'yes' during certain periods when the athlete exceeds normal training limits or competes in endurance events. Most studies have reported that the immune systems of athletes and nonathletes in the resting state are more similar than disparate with the exception of natural killer cell activity which tends to be elevated in athletes. Infection risk may be more related to the acute changes in immunity that occur following heavy exercise, but this hypothesis has not been sufficiently studied. 3) Are nutrition supplements effective countermeasures to exercise-induced inflammation and immunosuppression? Except for carbohydrate, the answer at this time for all other nutrients studied is 'no'. While data from the vitamin and mineral studies have been negative, and those involving glutamine conflicting, several investigations indicate that carbohydrate compared to placebo ingestion is associated with attenuated hormonal and immune responses.     

Heart rate variability in adolescents: relations to physical activity, fitness, and adiposity

PURPOSE: We determined the degree to which variation in cardiac autonomic modulation was explained by race, sex, moderate-vigorous physical activity (MVPA), cardiovascular fitness (CVF), percent body fat (%BF), waist girth, subcutaneous abdominal adipose tissue (SAAT), and visceral adipose tissue (VAT). METHODS: Subjects were 304 adolescents; SAAT and VAT values were available for 168 youths. Cardiac parasympathetic modulation (PM) was the root mean square of successive differences (RMSSD). Sympathetic-parasympathetic balance was the ratio of low- to high-frequency power (LFnu:HFnu). MVPA was measured with accelerometry, CVF with a treadmill, %BF with dual-energy x-ray absorptiometry (DXA), and SAAT and VAT with magnetic resonance imaging (MRI). RESULTS: Root mean square of successive differences was higher, and LFnu:HFnu was lower, in blacks than in whites. The final regression model revealed positive relations with CVF and MVPA, and a %BF by race by sex interaction, such that higher %BF was associated with lower RMSSD in black females and higher RMSSD in white females. Higher RMSSD was associated with lower VAT; for SAAT, the relationship was negative for blacks and positive for whites. For LFnu:Hfnu, a negative relationship was seen with MVPA and higher waist girth was associated with a higher ratio in blacks, but not in whites. Both higher VAT and SAAT were related to higher LFnu:HFnu. CONCLUSIONS: Black youths had a more favorable HRV profile than white youths. After controlling for age, race, and sex, more favorable HRV profiles were associated with more MVPA, better CVF, and less visceral and subcutaneous adiposity. The deleterious impact of higher adiposity was greater in blacks, especially females, than in whites. Enhancement of cardiac autonomic modulation may be a pathway through which physical activity, fitness, and leanness contribute to cardiovascular health early in life.     

When, why, and how to examine the heart during thoracic CT: Part 2, clinical applications

OBJECTIVE: CT examination of the thorax is often requested for the investigation of disorders that may have an important underlying cardiac cause or association that is not clinically obvious. Conditions such as idiopathic and acquired cardiomyopathy, ischemic heart disease, and valvular dysfunction may underlie symptoms such as dyspnea, chest pain, and hemoptysis that prompt the request for CT of the thorax. Other conditions such as pulmonary thromboembolic disease, chronic obstructive airways disease, pectus excavatum, sleep apnea, and many intrathoracic malignancies may have an important effect on cardiac structure and function. Patients undergoing thoracic surgery may have unsuspected coronary artery disease that can be detected in the course of preoperative evaluation by CT; similarly, postoperative complications often have a cardiogenic basis. CONCLUSION: Examination of the heart in the course of CT of the chest often can provide important and clinically relevant information that is not otherwise easily available.     

When, why, and how to examine the heart during thoracic CT: Part 1, basic principles

OBJECTIVE: MDCT systems with fast scanning capabilities can acquire images of the thorax with reduced cardiac motion artifacts, enabling improved evaluation of the heart and surrounding structures in the course of routine thoracic CT. This article describes the principles of including an evaluation of the heart in the course of a chest CT examination in terms of both examination technique and image interpretation. In addition, both the normal appearances and some of the most common abnormal appearances of the cardiac structures will be described. CONCLUSION: Details concerning the cardiac structures can inform interpretation of thoracic CT studies and can influence the patient's clinical management. Both unenhanced and contrast-enhanced scans can detect significant cardiac disorders that may otherwise go undetected. In certain situations, a CT examination of the entire chest, complemented by cardiac gating, can provide a more dedicated analysis of the heart and coronary arteries, providing both morphologic and functional information.     

Strategies of endoleak management following endoluminal treatment of abdominal aortic aneurysms in 95 patients: how, when and why

Purpose

This study reviews, on the basis of our experience, the indications and options for treating endoleaks (EL) after endovascular repair of abdominal aortic aneurysms (AAA) by endografting.

Materials and methods

Ninety-five patients (M/F =92/3; mean age at time of operation 70.7±7.8 years) who underwent endovascular repair of infrarenal AAA between April 1997 and October 2004 were considered. All images of 420 pre-and postoperative computed tomography (CT) studies were reviewed.

Results

A total of 37 EL occurred in 33/95 patients (34.7%), four of whom had two EL of different types. Eighteen EL were treated, 16 by endoluminal treatment. Six EL were type I: 2 were treated by percutaneous transluminal angioplasty (PTA) and 4 by cuff deployment (2 proximal cuffs and 2 distal cuffs). Eight EL were type II: 2 were treated by PTA, 2 by cuff deployment, 1 by transcatheter coil embolisation of the inferior mesenteric artery, two by thrombin injection in the aneurysm sac and one underwent surgical conversion during an attempt to treat a concomitant type I EL. Finally, 2 EL were type III: 1 was treated by PTA and 1 by cuff deployment. Endovascular treatment was successful in 12/16 cases (75%), whereas 3/16 cases (18.8%) were converted to open surgery, and 1 patient died of AAA rupture the day after endovascular repair.

Conclusions

EL is the most common complication after endovascular repair of AAA. In type I and type III EL, treatment is mandatory, whereas in type II (and type V) EL, treatment is indicated in the presence of AAA enlargement. Type IV EL generally disappear spontaneously. Endovascular repair is feasible and can be performed with different techniques according to EL aetiology, but it is not always decisive, and in some cases surgical conversion is required.     

Radiologists in the emergency department: when and how to use multislice CT

Chest pain is a challenging clinical problem in the emergency department. Despite advances in clinical diagnosis, many patients with atypical chest pain are needlessly hospitalized and others are mistakenly discharged. Faced with the specific clinical situation in which a patient has chest pain, an initially normal or inconclusive electrocardiogram, and normal cardiac biomarkers, multislice CT has proven useful for ruling out the conditions that involve the greatest morbidity and mortality and for establishing the cause of pain. This article reviews the current usefulness of multislice CT in the diagnostic workup of patients presenting at the emergency department with chest pain. We review the technique, define the most appropriate population, describe the acquisition protocols, and discuss the advantages and disadvantages of each study protocol.     

Physical activity in the management of obesity in adults: A position statement from Exercise and Sport Science Australia

This Position Statement examines the evidence for physical activity in weight and adiposity loss, prevention of weight and adiposity gain, and in weight regain in adults, and provides guidance on implications for exercise practitioners. Research evidence indicates that >150 min but preferably 300 min per week of aerobic activity of at least moderate intensity is required to prevent weight and adiposity gain, and at least the upper end of this range of activity to prevent weight regain after weight loss. For meaningful weight and total adiposity loss, a minimum of 300–420 min per week of aerobic activity of at least moderate intensity is required. The evidence around the volume of aerobic physical activity required to reduce central adiposity is emerging, and research suggests that it may be substantially less than that required for weight loss. The impact of high-intensity physical activity and resistance exercise for weight management is uncertain. During consultations for weight management, exercise practitioners should advise that metabolic and cardiovascular health benefits can be achieved with physical activity at any weight, and irrespective of weight change.