Eating disorder behavior in physically active Norwegian women

Competitive female athletes may have higher risk of eating disorders (ED) than recreational athletes, in part because low body fat may be advantageous in sports. However, women who participate in sports or physical activities might also do this for weight reduction, altering body shape, and for other food related reasons. This study was conducted to evaluate the association between hours of leisure time physical activity (PA) and prevalence of ED, and whether the association between the Eating Disorders Inventory (EDI) scales and ED, as classified by the Survey of Eating Disorders (SED), was the same among women with high vs. low physical activity levels. The community-based study sample consisted of 898 female students aged 18-50 years. Subjects filled out the EDI, the SED, and a questionnaire concerning physical activity and demographic data. Physical activity was not associated with increased risk of having a SED-defined diagnosis of an ED or of having an EDI score greater than 40, which is sometimes used to define women at risk for having an eating disorder. Women with a SED-defined ED had higher scores on all subscales of the EDI, but did not differ with respect to age, BMI or hours of weekly activity. The strongest predictors of having a SED-defined ED were body mass index (BMI), two EDI scales, drive of thinness and Bulimia Nervosa, with no differences between the two PA groups. Among women with a SED-defined ED, those with more than 5 h weekly PA did not differ from others with respect to scoring on the EDI or BMI. Results suggest that hours of physical activity may not increase risk of developing ED. Effective interventions are needed to help the growing numbers of persons with body-image and eating difficulties. For some, moderate physical training might be helpful.     

Effect of energy restriction and exercise on vitamin B-6 status of women during lactation

PURPOSE: Lactation increases vitamin B-6 requirements because its concentration in breast milk is related to maternal intake and it is essential for infants. Exercise may also increase the requirement because it increases utilization and excretion of vitamin B-6. Therefore, the purpose of this study was to determine whether energy restriction and exercise affected vitamin B-6 status of lactating women. METHODS: Breastfeeding women with a body mass index > or = 25 and < or = 30 kg x m(-2) were randomly assigned at 4 wk postpartum to either restrict energy intake by 500 kcal x d(-1) and exercise for 45 min x d(-1), 4 d x wk(-1) (weight loss group, WG) or maintain usual diet and not exercise (control group, CG) for 10 wk. Women were given a supplement containing 2.0 mg of vitamin B-6. Measurements included vitamin B-6 concentrations in breast milk and plasma, plasma pyridoxal 5'-phosphate, and erythrocyte alanine aminotransferase activity. RESULTS: The WG lost more weight (-4.4 +/- 0.4 vs -0.9 +/- 0.5 kg, P < 0.01) than the CG. Cardiovascular fitness increased by 12% in the WG, compared to 3% in the CG (P = 0.09). Milk vitamin B-6 concentrations increased in both groups (161 +/- 107 and 191 +/- 85 nmol x L(-1), WG and CG, respectively, P = 0.05). There were no significant differences in other vitamin B-6 parameters. Weight and length gain (2.06 +/- 0.21 and 1.83 +/- 0.17 kg; 8.6 +/- 0.6 and 7.2 +/- 0.5 cm; WG and CG, respectively) of infants was not significantly different between groups. CONCLUSIONS: Energy restriction and exercise from 4 to 14 wk postpartum in overweight, breastfeeding women consuming adequate dietary intakes and 2.0 mg of supplemental vitamin B-6 does not adversely affect vitamin B-6 status or infant growth.     

The relationship between eating disorders and personality in physically active women

The aim of the study was to examine the relationship between personality factors, self-reported eating disorders, type of physical activity, level of sport competition and hours spent on physical activity each week among physically active non-athletes and athletes. A total of 591 high school women participated in the study. The mean age was 19 during the data collection. Scores were obtained on the Karolinska Scales of Personality (KSP) and a questionnaire concerning eating disorders (1) and physical activity. All diagnoses were based upon the DSM-IV criteria for anorexia nervosa (AN), bulimia nervosa (BN) and eating disorder not otherwise specified (EDNOS). The prevalence of AN was 1.5%, BN 2.0%, AN+BN 0.3% and EDNOS 12.9%. The prevalence of eating disorders (ED) was highest among physically active non-athletes who were members of fitness clubs (odds ratio (OR)= 1.86, 95% CI: 1.08-2.79). However, there was no relationship between the prevalence of eating disorders and the level of sport competition or time spent on physical activity. The results showed that women with eating disorders scored higher in anxiety, hostility and detachment, and lower in socialisation than the women without eating disorders. The results indicated that individuals with certain personality characteristics had a higher risk for being classified with ED, but it does not seem to be related to whether they are physically active or not. The findings in this study may support the hypothesis that participating in physical activity can have some positive psychological effects, but this does not necessarily apply to patients with AN and BN. ED may have a biological/genetic explanation according to Eysenck's personality theory.     

Dietary protein requirements of physically active individuals

The dietary protein requirement of physically active individuals has received considerable scrutiny in recent years. Because the current United States Recommended Daily Allowance (USRDA) for protein (0.8 g/kg/day) already contains a safety margin (0.35 g/kg/day) to assure adequate protein intake, no increment in the USRDA was thought necessary to meet the demands of physical activity. Recently, collective evidence from research techniques utilising nitrogen balance, labelled amino acid isotopes, urea production and 3-methylhistidine excretion indicates that exercise (endurance and weightlifting) can significantly alter protein metabolism and that the dietary protein needs of physically active individuals may exceed the current USRDA. During endurance exercise, protein synthesis is depressed and protein degradation increases. Thus, amino acids become available for oxidation in energy-yielding processes. Amino acid catabolism has been estimated to contribute between 5 and 15% of the energy required during endurance exercise. Definitive conclusions regarding the changes that occur in protein synthesis and protein degradation during weightlifting exercise must await further research. The net contribution of amino acids to the energy required during weightlifting exercise is unknown but, due to the anaerobic nature of the event, it is most likely less than during endurance exercise. However, following both endurance and weightlifting exercise, protein synthesis increases. Based on current research, it is not yet possible to make recommendations for the daily protein needs of exercising individuals. It does appear that physically active individuals require more dietary protein per kilogram of bodyweight than sedentary individuals. However, when protein intake is expressed as a percentage of daily energy intake, physically active and sedentary individuals have similar requirements (approximately 12 to 15% of total energy as protein). Therefore, to cover the protein requirements of both physically active individuals and sedentary individuals it is suggested that future protein allowances be based on a percentage of the daily energy requirements. Protein consumption in excess of the current USRDA may minimise changes in body nitrogen stores, particularly during the first few weeks of training. However, further research is needed before a definitive conclusion can be made regarding protein ingestion and athletic performance.     

Effect of increasing the choice of active options on children's physically active play

ObjectivesTo determine whether increasing the choice of physical activity options increases the duration and intensity of children's physically active play.DesignThis cross-sectional laboratory study included gender (male and female) and choice group [single toy (no choice), three toys (low choice), five toys (high choice)] as between participant factors.MethodsBoys and girls (n = 36, 8–12 y) were stratified, randomly assigned to a choice group that always provided access to each participant's most liked active toy(s), and allowed 60 min of free time. The same sedentary alternatives were freely available to all participants. Physical activity outcomes were measured by accelerometry, heart rate, and direct observation.ResultsThe number of active toys the children played with increased (p < 0.001) across each choice group. Minutes spent in MPA were greater in the low choice (p < 0.05) and high choice (p < 0.02) groups than the no choice group. Active playtime was greater (p < 0.01) in the low choice (79%) and high choice (95%) groups compared to the no choice group. Girls in the low and high choice groups had greater (p < 0.05) percent heart rate reserve when compared to girls in the no choice group. There was no difference in the boys’ percent heart rate reserve between the no choice, low choice and high choice groups.ConclusionsIncreasing the choice of active toys increases both the duration and intensity of physically active play, especially in girls.     

Comparison of continuous and intermittent multistage maximal exercise testing during beta-adrenoceptor blockade in physically active men

Cardiorespiratory responses of 11 healthy males were studied, with placebo and propranolol, during a continuous and an intermittent multistage maximal treadmill test. With placebo, equivalent maximal heart rates were attained for the disparate test modes, and the intermittent protocol yielded a slightly higher (2%, P less than 0.01) maximal O2 consumption. In contrast, during beta-adrenoceptor blockade, higher maximal heart rates (5.1%, P less than 0.01) and O2 consumptions (4.4%, P less than 0.02) were reached with intermittent compared with continuous testing. Values were, however, markedly lower (P less than 0.001) for both protocols than with placebo. These results demonstrate that the precise degree of attenuation of maximal heart rate and O2 consumption observed in physically active persons receiving propranolol is partly dependent upon the actual test protocol utilized. Furthermore, the present data suggest an advantage for intermittent testing when accurate evaluation of the maximal cardiorespiratory capacity is desired in such individuals.     

Application of the Transtheoretical Model to physically active adults

BACKGROUND: A physically activity lifestyle has established health benefits, but interventions to increase exercise adherence have had mixed success. Examining physically active individuals could provide insight into strategies that are effective for exercise maintenance. The purpose of this study was to compare active adults based on exercise stage classification [action (ACT) and maintenance (MT)] according to the Transtheoretical Model (TTM). Physiological and psychosocial differences between stages were hypothesized to be consistent with theory and previous research. METHODS: A cross-sectional design was used to examine components of the TTM, exercise behavior, resting cardiovascular variables, and VO(peak). Data from 57 physically active college students (age= 21.2 +/- 3.7 yrs, 67% female, 71.9% Caucasian) were included in the analysis. TTM variables and self-report of behavior were measured with established questionnaires. VO(peak) was determined from expired gases during a maximal exercise test. RESULTS: Volume of weekly exercise and number of months consistently active were significantly greater for MT (n=35) than for ACT (n=22). When controlling for gender effects, VO(peak) and systolic blood pressure were also greater in MT than ACT. MT also scored higher than ACT on decisional balance (pros-cons of exercise) and 4 processes of change. CONCLUSIONS: Membership in MT and ACT stages was corroborated by aerobic capacity. Predicted differences in TTM components were only partially supported, but behavioral strategies were used more by participants who were consistently active longer. Physically active individuals should be studied over time to determine if targeting behavioral processes of change will enhance long-term exercise adherence.     

Short-term dietary energy restriction reduces lean body mass but not performance in physically active men and women.

We studied the effect of moderate, short-term energy restriction on physical performance in physically fit men (n = 13) and women (n = 11) in a controlled clinical research setting with a metabolic kitchen, exercise testing laboratory and training facility. The experiment consisted of a 10 d baseline period followed by either 2 wk of dietary energy restriction (750 kcal/d; n = 16) or energy balance (control; n = 8). During this 24 day study, exercise energy expenditure averaged 465 +/- 5.7 kcal/d in all subjects and was accomplished through treadmill running at a self-selected pace. Body weight was maintained in the control group (-0.36 +/- 0.24kg), but energy restriction resulted in weight loss of -1.29 +/- 0.16 kg (p < 0.001). There was a trend for lean body mass to decline more in the energy restriction group (p = 0.093), accounting for 61% of the weight loss, and urinary nitrogen excretion also tended to be higher in the energy restriction vs. control group (i.e., 13.2 +/- 1.1 vs. 11.2 +/- 1.0g/d; p = 0.089). Muscle strength (leg & shoulder press; 1 repetition maximum) was maintained or increased during the energy restriction period. Muscle endurance, assessed by leg squats to fatigue, and 5 mile run time improved following two weeks of energy restriction or balance. Anaerobic capacity (Wingate Test) increased slightly in the restriction (+ 368 +/- 219 joules) but declined in the control group 649 +/- 288 joules; p<0.05). We conclude that short-term (2 weeks) moderate energy restriction (approximately 750 kcal/d) results in weight loss but does not impair performance in physically fit young men and women.     

Reproductive profile of physically active men after exhaustive endurance exercise

The purpose of this study on non-professional (recreational) athletes was two-fold: 1) to determine if endurance exercise (EE) routinely used by professional athletes would produce reproductive changes in the general population, and 2) to assess reversion. Short-term exhaustive endurance exercise (EEE) can produce alterations in the hypothalamic-pituitary-gonadal (HPG) axis with subsequent fertility changes. Sixteen healthy adult male volunteers were divided into experimental (8) and control (8) groups for the exercise period. A cycloergometer provided EEE for a period of 2 weeks. The experimental group exercised four times a week; controls were without EEE. The hormonal and seminological profiles of all subjects were evaluated. Two weeks of EEE produced hormonal and seminological values in the experimental group that were statistically different from their own pre-treatment values (FSH: 3.33 +/- 1.7; LH: 3.73 +/- 1.36; sperm concentration/ml: 42.50 +/- 29.46; type a velocity: 25.23 +/- 10.9; type d velocity: 46.18 +/- 15.81; % of normal forms: 10.42 +/- 1.97) as well as from the pre- and post-treatment control group values. The measured parameters almost returned to pre-treatment levels in the experimental group 2 - 3 days after EEE ended. From this study we concluded that when subjected to EEE, individuals drawn from a recreational exercising life style experienced changes similar to those observed in studies done with athletes, and short-term EEE induced a reversible alteration to the HPG axis.     

Epidemiology of musculoskeletal injuries among sedentary and physically active adults

PURPOSE: This study describes the types and frequencies of musculoskeletal injuries among a cohort of adults with above average activity levels who were enrolled in the Aerobics Center Longitudinal Study (Dallas, TX). METHODS: Participants were adults aged 20-85 yr who completed a baseline clinical examination (1970-1982) and returned a mailed follow-up survey in 1986. Participants (5,028 men, 1,285 women) were measured for aerobic fitness, height, and body weight during the baseline examination. They reported detailed information about their physical activity levels and injury experiences on the follow-up survey (1986). An injury was defined as any self-reported soft tissue or bone injury that occurred within the previous 12 months. Activity-related injuries were those injuries participants attributed to participation in a formal exercise program. RESULTS: A quarter of all participants reported a musculoskeletal injury. Of these, 83% were activity-related. More than 66% of activity-related injuries occurred in the lower extremity; the knee was listed as the joint most often affected. There were no significant sex differences in the prevalence of injury, regardless of cause. Sport participants had the highest proportion of all-cause and activity-related musculoskeletal injuries among both men and women. Self-perceived severe injuries had a significant negative impact on physical activity levels since almost 1/3 of subjects reported permanently stopping their exercise program after injury. CONCLUSION: These results suggest the need for developing and implementing injury prevention programs targeted toward moderately active adults.     

Nandrolone excretion in sedentary vs physically trained young women

We investigated the effects of the menstrual cycle, oral contraception and physical training on exhaustive exercise-induced changes in the excretion of nandrolone metabolites [19-norandrosterone (19-NA), and 19-noretiocholanolone (19-NE)] in young women. Twenty-eight women were allocated to an untrained group ( n =16) or a trained group ( n =12), depending on their physical training background. The untrained group was composed of nine oral contraceptive users (OC+) and seven eumenorrheic women (OC−), while the trained group was entirely composed of OC+ subjects. Three laboratory sessions were conducted in a randomized order: a prolonged exercise test, a short-term exercise test and a control session. Urine specimens were collected before and 30, 60 and 90 min after the exercise test and at the same times of the day during the control session. Urinary concentrations of nandrolone metabolites were determined by gas chromatography coupled to mass spectrometry. Urinary concentrations of 19-NA and 19-NE ranged from undetectable levels to 1.14 and 0.47 ng/mL, respectively. Nandrolone excretion was not affected by the menstrual cycle phase (early follicular vs mid-luteal), prior physical training, oral contraception or acute physical exercise. Therefore, a urinary concentration of 2 ng/mL of 19-NA appears to be fair as the upper acceptable limit in doping control tests for female athletes.     

Nutrient intake of physically fit and unfit men and women

OBJECTIVE: Participation in physical activity and following a diet low in fat, saturated fat, and cholesterol and high in fiber are important in the prevention and treatment of cardiovascular disease and other health problems. Despite the importance of both behaviors, little is known about the interactive role of diet and physical activity. The association between physical activity and diet has been studied, but data on the association between cardiorespiratory fitness (CRF), which is an objective measure of habitual physical activity, and diet are lacking in adults. This report examines nutrient intakes of men and women across low, moderate, and high fitness categories and compares the intakes to national dietary recommendations. It is the first step in examining the relationship between diet, CRF, and morbidity and mortality endpoints in the Aerobics Center Longitudinal Study (ACLS). METHODS: Between 1987 and 1995, 7959 men and 2453 women participating in the ACLS provided 3-d diet records and completed a preventive medical examination. CRF was measured using a maximal exercise test, anthropometric and other clinical variables were measured following a standardized protocol, and lifestyle factors were assessed with a medical history questionnaire. RESULTS: After adjusting for potential confounders, there was a significantly lower percent of energy from fat and saturated fat across low, moderate, and high CRF categories. With additional adjustment for total energy intake, there was a significantly higher dietary fiber intake and a significantly lower cholesterol intake across CRF categories. The percentage of men and women meeting national dietary recommendations was higher at higher CRF levels. CONCLUSIONS: Men and women with higher fitness levels consumed diets that more closely approached national dietary recommendations than their lower fit peers.     

Television time and continuous metabolic risk in physically active adults

PURPOSE: Among Australian adults who met the public health guideline for the minimum health-enhancing levels of physical activity, we examined the dose-response associations of television-viewing time with continuous metabolic risk variables. METHODS: Data were analyzed on 2031 men and 2033 women aged > or = 25 yr from the 1999-2000 Australian Diabetes, Obesity and Lifestyle study without clinically diagnosed diabetes or heart disease, who reported at least 2.5 h.wk of moderate- to vigorous-intensity physical activity. Waist circumference, resting blood pressure, and fasting and 2-h plasma glucose, triglycerides, and high-density-lipoprotein cholesterol (HDL-C) were measured. The cross-sectional associations of these metabolic variables with quartiles and hours per day of self-reported television-viewing time were examined separately for men and for women. Analyses were adjusted for age, education, income, smoking, diet quality, alcohol intake, parental history of diabetes, and total physical activity time, as well as menopausal status and current use of postmenopausal hormones for women. RESULTS: Significant, detrimental dose-response associations of television-viewing time were observed with waist circumference, systolic blood pressure, and 2-h plasma glucose in men and women, and with fasting plasma glucose, triglycerides, and HDL-C in women. The associations were stronger in women than in men, with significant gender interactions observed for triglycerides and HDL-C. Though waist circumference attenuated the associations, they remained statistically significant for 2-h plasma glucose in men and women, and for triglycerides and HDL-C in women. CONCLUSIONS: In a population of healthy Australian adults who met the public health guideline for physical activity, television-viewing time was positively associated with a number of metabolic risk variables. These findings support the case for a concurrent sedentary behavior and health guideline for adults, which is in addition to the public health guideline on physical activity.     

Clinical management of the physically active patient with type 1 diabetes

The prevalence and incidence of type 1 diabetes continues to increase worldwide. Most patients with type 1 diabetes are young at the time of diagnosis and wish to continue leading a physically active life. Although regular exercise, insulin therapy, and proper nutrition are the cornerstone of treatment, there are considerable challenges in managing the active individual with type 1 diabetes. The current recommendation for diabetes management is intensive glycemic control for all patients when possible to help prevent secondary complications. Both insulin pump therapy and multiple daily injections are beneficial treatment options to lower average glucose levels; however, without continuous glucose monitoring, these treatment options typically increase the risk of hypoglycemia. In active patients with type 1 diabetes, the challenges of maintaining good glycemia are complicated by the inability to regulate insulin concentrations during and after exercise. Physiological and psychosocial factors during growth and maturation also provide additional challenges. This article highlights challenges and key strategies for diabetes management in the active individual with type 1 diabetes, including the application of the most recent diabetes technologies.     

Thicker radial cortex in physically active prepubertal girls compared to controls

This study was carried out to investigate the effects of physical activity on cortical bone of the radius in a population of prepubertal girls. Forty-nine healthy girls, 17 actives (10.62 +/- 1.56 years) and 32 controls (9.84 +/- 1.23 years) participated in this study. The active group was involved in gymnastics, judo, and dance on average 7.76 +/- 3.94 h/week. Bone mineral content (BMC) and density (BMD) were performed at the distal third of the non-dominant radius using DXA. The lean mass of the non-dominant forearm was derived from the total body analysis performed with DXA. In order to obtain bone cortical thickness, standard radiographs of the non-dominant radius were scanned and computed using a software program based on radiogrammetry. BMD and BMC values were higher in actives than in controls. Cortical thickness at the ulnar side correlated significantly with all the anthropometric and densitometric values as well as the duration of training. In addition, cortical thickness at the ulnar side was significantly higher in the actives compared to the controls. After adjustment for the duration of training per week, cortical thickness of the ulnar side did not differ any more between actives and controls. The same observation was obtained after adjustment for the forearm lean mass. In our active population, physical practice seemed to have induced greater BMC and higher cortical thickness than those observed in the sedentary.     

MRI abnormalities of foot and ankle in asymptomatic, physically active individuals

Objective. To assess MRI changes in the ankle and foot after physical exercise. Design and patients. Nineteen non-professional marathon runners and 19 age- and sex-matched controls volunteered for the study. All had ankle and foot MR images (1.5 T) taken in three perpendicular planes (STIR, T2F and T1FS sequences) within 3 h of running a full-length marathon (42.125 km). Three radiologists independently analysed the groups on a masked basis using a predefined form. Results. Severe bone marrow oedema was seen in one and slight bone marrow oedema in three marathon runners. Slight bone marrow oedema was found in three control subjects. Signal alteration within the soleus muscle, consistent with a grade 1 strain, was found in one marathon runner. Small punctate hyperintensities within the Achilles tendon were seen in 26% of the marathon runners and in 63% of controls (P=0.016). An increased amount of fluid in the retrocalcaneal bursa was found in one control and in none of the marathon runners. Small amounts of fluid in the retrocalcaneal bursa were seen in 68% of marathon runners and in 53% of controls. Grade 1 or 2 peritendinous joint fluid was found around 22% of tendons, among both marathon runners and controls, most often involving the tendon sheath of the flexor hallucis longus muscle. An increased amount of joint fluid was noted in 34% of the joints of the marathon runners, and in 18% of the controls. Conclusion. MRI shows several abnormalities in the ankle and foot both after marathon races and in asymptomatic physically active individuals without any preceding extraordinary strain. Recreational sports may lead to a number of positive MRI findings without correlation with clinical findings. Received: 3 May 2000 Revision requested: 11 July 2000 Revision received: 6 October 2000 Accepted: 13 November 2000     

Asian Indians of Guadeloupe are less physically active than their island counterparts

The status of ethnic minority has been reported to be associated with a tendency toward sedentary behavior. The Guadeloupean population is composed of Afro-Caribbeans and an Asian Indian minority. This study examined the association of ethnicity and physical activity on the island. Energy expenditures (EE), energy intakes (EI), and macronutrient intakes of 122 Guadeloupean workers (60 Indians and 62 controls) were assessed by three consecutive 24-h recalls. Two-way analyses of variance were conducted to test the hypothesis of an effect of ethnicity, taking the potential effect of sex into account, on these variables. Asian Indians reported lower EE ( P =0.011), lower EE/EI ratios ( P =0.001), and lower physical activity ( P =0.003) than their Afro-Carribean counterparts. Their food intakes were not different in terms of EI or macronutrient intake. No sex × ethnicity interactions were significant. The present study reports a tendency toward physical inactivity in Asian Indians of Guadeloupe associated with EI similar to those of controls. Sedentary lifestyles and energetic imbalances are well-documented risk factors for several diseases, including type 2 diabetes and cardiovascular disease, both major public health concerns in Guadeloupe. Strategies to prevent sedentary lifestyles should be considered for Asian Indian Guadeloupeans.