Importance:Little evidence exists on which exercise modality is optimal for obese adolescents. Ob... more Importance:Little evidence exists on which exercise modality is optimal for obese adolescents. Objective: To determine the effects of aerobic training, resistance training, and combined training on percentage body fat in overweight and obese adolescents.Design, Setting, and Participants:Randomized, parallel-group clinical trial at community-based exercise facilities in Ottawa (Ontario) and Gatineau (Quebec), Canada, among previously inactive postpubertal adolescents aged 14-18 years (Tanner stage IV or V) with body mass index at or above the 95th percentile for age and sex or at or above the 85th percentile plus an additional diabetes mellitus or cardiovascular risk factor. Interventions: After a 4-week run-in period, 304 participants were randomized to the following 4 groups for 22 weeks: aerobic training (n = 75), resistance training (n = 78), combined aerobic and resistance training (n = 75), or nonexercising control (n = 76). All participants received dietary counseling, with a daily energy deficit of 250 kcal.Main Outcomes and Measures:The primary outcome was percentage body fat measured by magnetic resonance imaging at baseline and 6 months. We hypothesized that aerobic training and resistance training would each yield greater decreases than the control and that combined training would cause greater decreases than aerobic or resistance training alone.Results:Decreases in percentage body fat were −0.3 (95% CI, −0.9 to 0.3) in the control group, −1.1 (95% CI, −1.7 to −0.5) in the aerobic training group (p = .06 vs. controls), and −1.6 (95% CI, −2.2 to −1.0) in the resistance training group (p = .002 vs controls). The −1.4 (95% CI, −2.0 to −0.8) decrease in the combined training group did not differ significantly from that in the aerobic or resistance training group. Waist circumference changes were −0.2 (95% CI, −1.7 to 1.2) cm in the control group, −3.0 (95% CI, −4.4 to −1.6) cm in the aerobic group (p = .006 vs controls), −2.2 (95% CI −3.7 to −0.8) cm in the resistance training group (p = .048 vs controls), and −4.1 (95% CI, −5.5 to −2.7) cm in the combined training group. In per-protocol analyses (> 70% adherence), the combined training group had greater changes in percentage body fat (-2.4, 95% CI, −3.2 to −1.6) vs the aerobic group (-1.2; 95% CI, −2.0 to −0.5; p = .04 vs the combined group) but not the resistance group (-1.6; 95% CI, −2.5 to −0.8).Conclusions and Relevance:Aerobic, resistance, and combined training reduced total body fat and waist circumference in obese adolescents. In more adherent participants, combined training may cause greater decreases than aerobic or resistance training alone.
Journal of Pediatric Endocrinology and Metabolism, 2013
Introduction: Obesity has become the most common modern pediatric chronic disease. Early preventi... more Introduction: Obesity has become the most common modern pediatric chronic disease. Early prevention and treatment of childhood and adolescent obesity is mandated. Severe obesity [body mass index (BMI) percentile > 98 % ] reduces the likelihood of the multidisciplinary childhood obesity program to succeed, suggesting, most probably, that a more intense program is needed to treat severely obese children. To prospectively examine the effects of an intense, 3-month, combined dietary-behavioral-physical activity intervention on anthropometric measures, leisure time activity patterns, and fitness in prepubertal severely obese (BMI percentile > 98 % ) children (n = 22) compared to age, gender, and obesity matched controls (n = 18). Results: At 3 months, there were significant differences (p < 0.05) in changes in body weight ( -0.5 ± 2.4 vs. 1.7 ± 1.9 kg), BMI ( -0.9 ± 1.2 vs. 0.4 ± 1.0 kg/m 2 ), BMI percentile (0.39 ± 0.39 % vs. -0.04 ± 0.32 % ), sum skinfolds ( -3.1 ± 8.1 vs. 1.1 ± 4.7 mm), total habitual physical activity (25.4 ± 10.8 vs. 0.3 ± 10.1 Mets), and fitness (142 ± 72 vs. -8 ± 88 s) in the intervention vs. control participants. Conclusions: Our data demonstrate the beneficial, shortterm effects of an intense combined dietary-behavioralphysical activity intervention on anthropometric measures, activity patterns, and fitness in severely obese children. However, despite the encouraging results, the modest effect on BMI percentiles emphasizes the difficulty of treating severely obese children using the conventional nutritional-behavioral-physical activity approach.
International Journal of Behavioral Nutrition and Physical Activity, 2012
Objective: The aim of the present study was to determine physical activity (PA) and nutrition kno... more Objective: The aim of the present study was to determine physical activity (PA) and nutrition knowledge and preferences in low socioeconomic status kindergarten children. Methods: Following height and weight measurement, 795 low socioeconomic status kindergarten children (age 3.8-6.8 y.o) completed a photo-pair knowledge and preferences food and exercise questionnaire. Results: No difference was found between nutrition and PA knowledge scores (52.3 ± 0.9 versus 52.6 ± 0.8%, respectively). There was no difference between the nutrition knowledge and preference score (52.3 ± 0.9 versus 50.9 ± 0.9%, respectively). PA preference was significantly higher than knowledge (56.9 ± 1.5 versus 52.6 ± 0.8%, respectively; p < 0.0001). Significant correlations were found between nutrition knowledge and preferences (r = 0.55, p < 0.0001), physical activity knowledge and preferences (r = 0.46, p < 0.0001), and nutrition and PA preferences (r = 0.46, p < 0.001). Nutrition preference scores were significantly lower in overweight compared to normal weight kindergartners 48.1 ± 1.7 versus 52.0 ± 1.0%; p < 0.05). PA knowledge and preference scores were significantly higher among male compared to the female kindergartners (p < 0.001 for both). Conclusion: Our data demonstrate diversities in physical activity and nutrition knowledge and preferences among low socioeconomic status kindergarten children. These findings may be important for the development of health promotion programs in low socioeconomic kindergarten children.
Importance:Little evidence exists on which exercise modality is optimal for obese adolescents. Ob... more Importance:Little evidence exists on which exercise modality is optimal for obese adolescents. Objective: To determine the effects of aerobic training, resistance training, and combined training on percentage body fat in overweight and obese adolescents.Design, Setting, and Participants:Randomized, parallel-group clinical trial at community-based exercise facilities in Ottawa (Ontario) and Gatineau (Quebec), Canada, among previously inactive postpubertal adolescents aged 14-18 years (Tanner stage IV or V) with body mass index at or above the 95th percentile for age and sex or at or above the 85th percentile plus an additional diabetes mellitus or cardiovascular risk factor. Interventions: After a 4-week run-in period, 304 participants were randomized to the following 4 groups for 22 weeks: aerobic training (n = 75), resistance training (n = 78), combined aerobic and resistance training (n = 75), or nonexercising control (n = 76). All participants received dietary counseling, with a daily energy deficit of 250 kcal.Main Outcomes and Measures:The primary outcome was percentage body fat measured by magnetic resonance imaging at baseline and 6 months. We hypothesized that aerobic training and resistance training would each yield greater decreases than the control and that combined training would cause greater decreases than aerobic or resistance training alone.Results:Decreases in percentage body fat were −0.3 (95% CI, −0.9 to 0.3) in the control group, −1.1 (95% CI, −1.7 to −0.5) in the aerobic training group (p = .06 vs. controls), and −1.6 (95% CI, −2.2 to −1.0) in the resistance training group (p = .002 vs controls). The −1.4 (95% CI, −2.0 to −0.8) decrease in the combined training group did not differ significantly from that in the aerobic or resistance training group. Waist circumference changes were −0.2 (95% CI, −1.7 to 1.2) cm in the control group, −3.0 (95% CI, −4.4 to −1.6) cm in the aerobic group (p = .006 vs controls), −2.2 (95% CI −3.7 to −0.8) cm in the resistance training group (p = .048 vs controls), and −4.1 (95% CI, −5.5 to −2.7) cm in the combined training group. In per-protocol analyses (&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt; 70% adherence), the combined training group had greater changes in percentage body fat (-2.4, 95% CI, −3.2 to −1.6) vs the aerobic group (-1.2; 95% CI, −2.0 to −0.5; p = .04 vs the combined group) but not the resistance group (-1.6; 95% CI, −2.5 to −0.8).Conclusions and Relevance:Aerobic, resistance, and combined training reduced total body fat and waist circumference in obese adolescents. In more adherent participants, combined training may cause greater decreases than aerobic or resistance training alone.
In contrast to the effect of exercise training on the menstrual cycle in female athletes, the eff... more In contrast to the effect of exercise training on the menstrual cycle in female athletes, the effect of physical activity on the male reproductive system is described far less extensively in the scientific literature. The male reproductive system consists of the hypothalamic-pituitary unit and the testes. The testes are responsible for the production of sperm and androgens, mainly testosterone. Androgens are responsible for the development of secondary male characteristics, muscle and bone growth, production of red blood cells, sex drive and other behavioral aspects. The effect of physical activity on the male reproductive axis depends on the intensity and duration of the activity, the fitness level of the individual, and his nutritional status. A single bout of short and intensive aerobic and anaerobic exercise usually increases serum testosterone level. Prolonged moderate to intense exercise (> 2 hours) leads to an initial increase followed by a decline to or below the baseline levels. Exercise training frequently results in a decrease of serum testosterone, and may rarely be associated with reduced libido, sperm production and fertility. In addition, the reduced testosterone levels may attenuate the exercise-associated muscle hypertrophy, reduce the repair of muscle damage, reduce post exercise muscle rehabilitation and may play an important role in the development of over-training syndrome. Other consequences include decreased bone density and a possible effect on mood and behavior. Surprisingly, even in the medically well-supervised elite athletes, changes in testosterone levels and their effects on performance and health are rarely evaluated.
Children do not typically appear to move with the same skill and dexterity as adults, although th... more Children do not typically appear to move with the same skill and dexterity as adults, although they can still improve their motor performance in specific tasks with practice. One possible explanation is that their motor performance is limited by an inherently higher level of movement variability, but that their motor adaptive ability is robust to this variability. To test this hypothesis, we examined motor adaptation of 43 children (ages 6-17) and 12 adults as they reached while holding the tip of a lightweight robot. The robot applied either a predictable, velocity-dependent field (the "mean field") or a similar field that incorporated stochastic variation (the "noise field"), thereby further enhancing the variability of the subjects' movements. We found that children exhibited greater initial trial-to-trial variability in their unperturbed movements but were still able to adapt comparably to adults in both the mean and noise fields. Furthermore, the youngest children (ages 6-8) were able to reduce their variability with practice to levels comparable to the remaining children groups although not as low as adults. These results indicate that children as young as age 6 possess adult-like neural systems for motor adaptation and internal model formation that allow them to adapt to novel dynamic environments as well as adults on average despite increased neuromotor or environmental noise. Performance after adaptation is still more variable than adults, however, indicating that movement inconsistency, not motor adaptation inability, ultimately limits motor performance by children and may thus account for their appearance of incoordination and more frequent motor accidents (e.g., spilling, tripping). The results of this study also suggest that movement variability in young children may arise from two sources-a relatively constant, intrinsic source related to fundamental physiological constraints of the developing motor system and a more rapidly modifiable source that is modulated depending on the current motor context.
Forty-three patients with epithelial ovarian carcinoma, were treated by cyclophosphamide and cisp... more Forty-three patients with epithelial ovarian carcinoma, were treated by cyclophosphamide and cisplatin (CP) following initial laparotomy. The mean dose intensity (DI) and mean relative dose intensity (RDI) respectively were for cyclophosphamide: 166.69 mg/sqm/week and 0.67, and for cisplatin: 16.29 mg/sqm/week and 0.65. The mean average relative dose intensity (ARDI) was 0.66. The three-year survival for all patients was 44.3%. The three-year survival for patients receiving cyclophosphamide with a RDI of more than median value was 63.82%, while for patients receiving cyclophosphamide with a RDI of less than median value three-year survival was 26.3% (p < 0.02). The three-year survival for patients receiving cisplatin with an RDI of more than median value was 62.01%, as compared to 24.17% for patients receiving cisplatin with a RDI of less than median value (p < 0.02). The three-year survival for patients receiving the CP regimen with an ARDI of more than median value was significantly higher than that for patients receiving the CP regimen with an ARDI of less than median value (63.82% versus 26.03%, p < 0.02). Dose intensity of cisplatin-based chemotherapy in epithelial ovarian carcinoma is an important factor affecting survival.
Objective: To perform a literature review of the current available data on protein and amino acid... more Objective: To perform a literature review of the current available data on protein and amino acid supplementation in sports, their efficacy and safety. Data sources: The search was limited to English language citations published in the years 1980-2007. MEDLINE and PubMed searches were performed in March 2007 on all studies using the Mesh terms: proteins, amino acids, supplement, the desired supplement name and sports / exercise. Study section: Initially, only randomised controlled clinical trials were included in the analysis. In addition, several recent reviews and relevant meta-analyses were used. Data extraction: A title scan was performed to exclude references that did not include protein supplementation, exercise, or the population's health status was abnormal. Relevant literature was identified, sourced, and reviewed and the selected manuscripts are cited. Data synthesis: Although protein supplementation has been widely discussed in the literature for many years, it was surprising to find the relatively low number of randomised controlled trials that met the inclusion criteria for this review. When the general terms "protein / amino acids" were used, 43 citations met the criteria; "creatine" yielded 53 citations; "glutamine" 2 citations, and "β-hydroxy-β-methylbutyric acid (HMB)" 9 citations. The bulk of the data suggests that protein requirements are usually met by an iso-caloric, balanced diet, for both endurance and resistance training. Supplementing the athlete's diet with protein or amino acids has not proven beneficial and may even sometimes be harmful. Creatine is currently the only product that has clear scientific support to enhance sporting performance. The timing of protein supplementation may be an important factor in trying to achieve anabolic effects. Conclusions: The use of protein supplements for the healthy, non-competitive adult engaged in recreational sports is usually not warranted. There are only limited data to support protein supplementation in competitive sports. There is some evidence supporting the use of creatine and possibly HMB as ergogenic aids in specific situations. Further research is needed before definitive recommendations can be made on the type, timing and effectiveness of protein supplements.
Ethiopian runners are famous for their achievements in long-distance running. The recent immigrat... more Ethiopian runners are famous for their achievements in long-distance running. The recent immigration of Ethiopians to Israel provided an opportunity to compare some physiological variables between elite Ethiopian and white Israeli runners. Six Ethiopian and five white Israeli runners, aged 20 to 40 years, were studied before and after an 11 km race. Venous blood was sampled from each runner prior to the race, and 1 h, 48 h, and 5 days following the race. The activities of creatine kinase (CK), lactate dehydrogenase (LDH) and aspartate aminotransferase (AST) were measured, and levels of serum electrolytes, urea, creatinine, phosphorus, albumin, cholesterol, and alkaline phosphatase were also determined. CK activity rose 2.6-fold with a peak 5 days after the race. LDH and AST levels rose as well (1.4-1.3-fold, respectively). Significant elevations also occurred in serum phosphorus, uric acid, and creatinine concentrations 1 h after the race. In contrast to previous studies in which higher enzyme activities were reported in blacks, we did not detect any difference in serum enzyme values between black and white runners.
Journal of Strength and Conditioning Research, 2011
A case study of virilizing adrenal tumor in an adolescent female elite tennis playerinsight into ... more A case study of virilizing adrenal tumor in an adolescent female elite tennis playerinsight into the use of anabolic steroids in young athletes.
Journal of Pediatric Gastroenterology and Nutrition, Aug 1, 2003
Polyethylene glycol solution (PEG) is a purgative solution most commonly used for bowel preparati... more Polyethylene glycol solution (PEG) is a purgative solution most commonly used for bowel preparation in both adults and children. Nasogastric infusion of PEG is considered a safe and effective means of administration when patients cannot or will not take the solution orally. Nausea, vomiting, and bloating are commonly reported adverse reactions. We present an 8-year-old girl with life-threatening respiratory failure after aspiration of PEG, which was treated successfully by bronchoalveolar lavage. CASE REPORT The patient was an 8-year-old girl with chronic abdominal pain. Two months before her current admission, she was diagnosed with fecal impaction and had a successful disimpaction with PEG solution. Because her abdominal pain had continued, the patient was admitted to a regional hospital for intestinal lavage and colonoscopy. A nasogastric tube was placed with difficulty and PEG solution was infused via the nasogastric tube. No radiographic verification of the position of the nasogastric tube was obtained. The patient subsequently vomited several times. Two hours after starting the infusion, the patient experienced difficulty breathing, chest pain, and tachypnea, which became worse during the following few hours. Oxygen saturation was 70% on room air. Respiratory rate was 50 to 70 breaths per minute. The patient was placed on supplemented oxygen therapy, up to 100% oxygen via a non-rebreathing mask. Arterial blood gas obtained while the patient was on 100% oxygen supplement showed pH 7.38, pCO 2 38 mm Hg, paO 2 93 mmHg, BE-2 and HCO3-22. Chest roentgenogram
Journal of Pediatric Endocrinology and Metabolism, 2013
Persistent hyperinsulinemic hypoglycemia of infancy (PHHI), the most common cause of persistent h... more Persistent hyperinsulinemic hypoglycemia of infancy (PHHI), the most common cause of persistent hypoglycemia in the neonatal period and infancy, is a genetic disorder characterized by abnormal regulation of insulin secretion. Octreotide, a somatostatin analog, is often used as a second-line treatment when diazoxide therapy fails to control hypoglycemia. We report herein a rare development of octreotide-induced hepatitis following prolonged treatment for PHHI in an infant. Octreotide-induced hepatitis may occur mostly when high doses are given, or when dosing is increased. This warrants routine examination of liver function. When hepatitis develops, prompt cessation of octreotide therapy will probably result in subsequent resolution.
Importance:Little evidence exists on which exercise modality is optimal for obese adolescents. Ob... more Importance:Little evidence exists on which exercise modality is optimal for obese adolescents. Objective: To determine the effects of aerobic training, resistance training, and combined training on percentage body fat in overweight and obese adolescents.Design, Setting, and Participants:Randomized, parallel-group clinical trial at community-based exercise facilities in Ottawa (Ontario) and Gatineau (Quebec), Canada, among previously inactive postpubertal adolescents aged 14-18 years (Tanner stage IV or V) with body mass index at or above the 95th percentile for age and sex or at or above the 85th percentile plus an additional diabetes mellitus or cardiovascular risk factor. Interventions: After a 4-week run-in period, 304 participants were randomized to the following 4 groups for 22 weeks: aerobic training (n = 75), resistance training (n = 78), combined aerobic and resistance training (n = 75), or nonexercising control (n = 76). All participants received dietary counseling, with a daily energy deficit of 250 kcal.Main Outcomes and Measures:The primary outcome was percentage body fat measured by magnetic resonance imaging at baseline and 6 months. We hypothesized that aerobic training and resistance training would each yield greater decreases than the control and that combined training would cause greater decreases than aerobic or resistance training alone.Results:Decreases in percentage body fat were −0.3 (95% CI, −0.9 to 0.3) in the control group, −1.1 (95% CI, −1.7 to −0.5) in the aerobic training group (p = .06 vs. controls), and −1.6 (95% CI, −2.2 to −1.0) in the resistance training group (p = .002 vs controls). The −1.4 (95% CI, −2.0 to −0.8) decrease in the combined training group did not differ significantly from that in the aerobic or resistance training group. Waist circumference changes were −0.2 (95% CI, −1.7 to 1.2) cm in the control group, −3.0 (95% CI, −4.4 to −1.6) cm in the aerobic group (p = .006 vs controls), −2.2 (95% CI −3.7 to −0.8) cm in the resistance training group (p = .048 vs controls), and −4.1 (95% CI, −5.5 to −2.7) cm in the combined training group. In per-protocol analyses (&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt; 70% adherence), the combined training group had greater changes in percentage body fat (-2.4, 95% CI, −3.2 to −1.6) vs the aerobic group (-1.2; 95% CI, −2.0 to −0.5; p = .04 vs the combined group) but not the resistance group (-1.6; 95% CI, −2.5 to −0.8).Conclusions and Relevance:Aerobic, resistance, and combined training reduced total body fat and waist circumference in obese adolescents. In more adherent participants, combined training may cause greater decreases than aerobic or resistance training alone.
Journal of Pediatric Endocrinology and Metabolism, 2013
Introduction: Obesity has become the most common modern pediatric chronic disease. Early preventi... more Introduction: Obesity has become the most common modern pediatric chronic disease. Early prevention and treatment of childhood and adolescent obesity is mandated. Severe obesity [body mass index (BMI) percentile > 98 % ] reduces the likelihood of the multidisciplinary childhood obesity program to succeed, suggesting, most probably, that a more intense program is needed to treat severely obese children. To prospectively examine the effects of an intense, 3-month, combined dietary-behavioral-physical activity intervention on anthropometric measures, leisure time activity patterns, and fitness in prepubertal severely obese (BMI percentile > 98 % ) children (n = 22) compared to age, gender, and obesity matched controls (n = 18). Results: At 3 months, there were significant differences (p < 0.05) in changes in body weight ( -0.5 ± 2.4 vs. 1.7 ± 1.9 kg), BMI ( -0.9 ± 1.2 vs. 0.4 ± 1.0 kg/m 2 ), BMI percentile (0.39 ± 0.39 % vs. -0.04 ± 0.32 % ), sum skinfolds ( -3.1 ± 8.1 vs. 1.1 ± 4.7 mm), total habitual physical activity (25.4 ± 10.8 vs. 0.3 ± 10.1 Mets), and fitness (142 ± 72 vs. -8 ± 88 s) in the intervention vs. control participants. Conclusions: Our data demonstrate the beneficial, shortterm effects of an intense combined dietary-behavioralphysical activity intervention on anthropometric measures, activity patterns, and fitness in severely obese children. However, despite the encouraging results, the modest effect on BMI percentiles emphasizes the difficulty of treating severely obese children using the conventional nutritional-behavioral-physical activity approach.
International Journal of Behavioral Nutrition and Physical Activity, 2012
Objective: The aim of the present study was to determine physical activity (PA) and nutrition kno... more Objective: The aim of the present study was to determine physical activity (PA) and nutrition knowledge and preferences in low socioeconomic status kindergarten children. Methods: Following height and weight measurement, 795 low socioeconomic status kindergarten children (age 3.8-6.8 y.o) completed a photo-pair knowledge and preferences food and exercise questionnaire. Results: No difference was found between nutrition and PA knowledge scores (52.3 ± 0.9 versus 52.6 ± 0.8%, respectively). There was no difference between the nutrition knowledge and preference score (52.3 ± 0.9 versus 50.9 ± 0.9%, respectively). PA preference was significantly higher than knowledge (56.9 ± 1.5 versus 52.6 ± 0.8%, respectively; p < 0.0001). Significant correlations were found between nutrition knowledge and preferences (r = 0.55, p < 0.0001), physical activity knowledge and preferences (r = 0.46, p < 0.0001), and nutrition and PA preferences (r = 0.46, p < 0.001). Nutrition preference scores were significantly lower in overweight compared to normal weight kindergartners 48.1 ± 1.7 versus 52.0 ± 1.0%; p < 0.05). PA knowledge and preference scores were significantly higher among male compared to the female kindergartners (p < 0.001 for both). Conclusion: Our data demonstrate diversities in physical activity and nutrition knowledge and preferences among low socioeconomic status kindergarten children. These findings may be important for the development of health promotion programs in low socioeconomic kindergarten children.
Importance:Little evidence exists on which exercise modality is optimal for obese adolescents. Ob... more Importance:Little evidence exists on which exercise modality is optimal for obese adolescents. Objective: To determine the effects of aerobic training, resistance training, and combined training on percentage body fat in overweight and obese adolescents.Design, Setting, and Participants:Randomized, parallel-group clinical trial at community-based exercise facilities in Ottawa (Ontario) and Gatineau (Quebec), Canada, among previously inactive postpubertal adolescents aged 14-18 years (Tanner stage IV or V) with body mass index at or above the 95th percentile for age and sex or at or above the 85th percentile plus an additional diabetes mellitus or cardiovascular risk factor. Interventions: After a 4-week run-in period, 304 participants were randomized to the following 4 groups for 22 weeks: aerobic training (n = 75), resistance training (n = 78), combined aerobic and resistance training (n = 75), or nonexercising control (n = 76). All participants received dietary counseling, with a daily energy deficit of 250 kcal.Main Outcomes and Measures:The primary outcome was percentage body fat measured by magnetic resonance imaging at baseline and 6 months. We hypothesized that aerobic training and resistance training would each yield greater decreases than the control and that combined training would cause greater decreases than aerobic or resistance training alone.Results:Decreases in percentage body fat were −0.3 (95% CI, −0.9 to 0.3) in the control group, −1.1 (95% CI, −1.7 to −0.5) in the aerobic training group (p = .06 vs. controls), and −1.6 (95% CI, −2.2 to −1.0) in the resistance training group (p = .002 vs controls). The −1.4 (95% CI, −2.0 to −0.8) decrease in the combined training group did not differ significantly from that in the aerobic or resistance training group. Waist circumference changes were −0.2 (95% CI, −1.7 to 1.2) cm in the control group, −3.0 (95% CI, −4.4 to −1.6) cm in the aerobic group (p = .006 vs controls), −2.2 (95% CI −3.7 to −0.8) cm in the resistance training group (p = .048 vs controls), and −4.1 (95% CI, −5.5 to −2.7) cm in the combined training group. In per-protocol analyses (&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt; 70% adherence), the combined training group had greater changes in percentage body fat (-2.4, 95% CI, −3.2 to −1.6) vs the aerobic group (-1.2; 95% CI, −2.0 to −0.5; p = .04 vs the combined group) but not the resistance group (-1.6; 95% CI, −2.5 to −0.8).Conclusions and Relevance:Aerobic, resistance, and combined training reduced total body fat and waist circumference in obese adolescents. In more adherent participants, combined training may cause greater decreases than aerobic or resistance training alone.
In contrast to the effect of exercise training on the menstrual cycle in female athletes, the eff... more In contrast to the effect of exercise training on the menstrual cycle in female athletes, the effect of physical activity on the male reproductive system is described far less extensively in the scientific literature. The male reproductive system consists of the hypothalamic-pituitary unit and the testes. The testes are responsible for the production of sperm and androgens, mainly testosterone. Androgens are responsible for the development of secondary male characteristics, muscle and bone growth, production of red blood cells, sex drive and other behavioral aspects. The effect of physical activity on the male reproductive axis depends on the intensity and duration of the activity, the fitness level of the individual, and his nutritional status. A single bout of short and intensive aerobic and anaerobic exercise usually increases serum testosterone level. Prolonged moderate to intense exercise (> 2 hours) leads to an initial increase followed by a decline to or below the baseline levels. Exercise training frequently results in a decrease of serum testosterone, and may rarely be associated with reduced libido, sperm production and fertility. In addition, the reduced testosterone levels may attenuate the exercise-associated muscle hypertrophy, reduce the repair of muscle damage, reduce post exercise muscle rehabilitation and may play an important role in the development of over-training syndrome. Other consequences include decreased bone density and a possible effect on mood and behavior. Surprisingly, even in the medically well-supervised elite athletes, changes in testosterone levels and their effects on performance and health are rarely evaluated.
Children do not typically appear to move with the same skill and dexterity as adults, although th... more Children do not typically appear to move with the same skill and dexterity as adults, although they can still improve their motor performance in specific tasks with practice. One possible explanation is that their motor performance is limited by an inherently higher level of movement variability, but that their motor adaptive ability is robust to this variability. To test this hypothesis, we examined motor adaptation of 43 children (ages 6-17) and 12 adults as they reached while holding the tip of a lightweight robot. The robot applied either a predictable, velocity-dependent field (the "mean field") or a similar field that incorporated stochastic variation (the "noise field"), thereby further enhancing the variability of the subjects' movements. We found that children exhibited greater initial trial-to-trial variability in their unperturbed movements but were still able to adapt comparably to adults in both the mean and noise fields. Furthermore, the youngest children (ages 6-8) were able to reduce their variability with practice to levels comparable to the remaining children groups although not as low as adults. These results indicate that children as young as age 6 possess adult-like neural systems for motor adaptation and internal model formation that allow them to adapt to novel dynamic environments as well as adults on average despite increased neuromotor or environmental noise. Performance after adaptation is still more variable than adults, however, indicating that movement inconsistency, not motor adaptation inability, ultimately limits motor performance by children and may thus account for their appearance of incoordination and more frequent motor accidents (e.g., spilling, tripping). The results of this study also suggest that movement variability in young children may arise from two sources-a relatively constant, intrinsic source related to fundamental physiological constraints of the developing motor system and a more rapidly modifiable source that is modulated depending on the current motor context.
Forty-three patients with epithelial ovarian carcinoma, were treated by cyclophosphamide and cisp... more Forty-three patients with epithelial ovarian carcinoma, were treated by cyclophosphamide and cisplatin (CP) following initial laparotomy. The mean dose intensity (DI) and mean relative dose intensity (RDI) respectively were for cyclophosphamide: 166.69 mg/sqm/week and 0.67, and for cisplatin: 16.29 mg/sqm/week and 0.65. The mean average relative dose intensity (ARDI) was 0.66. The three-year survival for all patients was 44.3%. The three-year survival for patients receiving cyclophosphamide with a RDI of more than median value was 63.82%, while for patients receiving cyclophosphamide with a RDI of less than median value three-year survival was 26.3% (p < 0.02). The three-year survival for patients receiving cisplatin with an RDI of more than median value was 62.01%, as compared to 24.17% for patients receiving cisplatin with a RDI of less than median value (p < 0.02). The three-year survival for patients receiving the CP regimen with an ARDI of more than median value was significantly higher than that for patients receiving the CP regimen with an ARDI of less than median value (63.82% versus 26.03%, p < 0.02). Dose intensity of cisplatin-based chemotherapy in epithelial ovarian carcinoma is an important factor affecting survival.
Objective: To perform a literature review of the current available data on protein and amino acid... more Objective: To perform a literature review of the current available data on protein and amino acid supplementation in sports, their efficacy and safety. Data sources: The search was limited to English language citations published in the years 1980-2007. MEDLINE and PubMed searches were performed in March 2007 on all studies using the Mesh terms: proteins, amino acids, supplement, the desired supplement name and sports / exercise. Study section: Initially, only randomised controlled clinical trials were included in the analysis. In addition, several recent reviews and relevant meta-analyses were used. Data extraction: A title scan was performed to exclude references that did not include protein supplementation, exercise, or the population's health status was abnormal. Relevant literature was identified, sourced, and reviewed and the selected manuscripts are cited. Data synthesis: Although protein supplementation has been widely discussed in the literature for many years, it was surprising to find the relatively low number of randomised controlled trials that met the inclusion criteria for this review. When the general terms "protein / amino acids" were used, 43 citations met the criteria; "creatine" yielded 53 citations; "glutamine" 2 citations, and "β-hydroxy-β-methylbutyric acid (HMB)" 9 citations. The bulk of the data suggests that protein requirements are usually met by an iso-caloric, balanced diet, for both endurance and resistance training. Supplementing the athlete's diet with protein or amino acids has not proven beneficial and may even sometimes be harmful. Creatine is currently the only product that has clear scientific support to enhance sporting performance. The timing of protein supplementation may be an important factor in trying to achieve anabolic effects. Conclusions: The use of protein supplements for the healthy, non-competitive adult engaged in recreational sports is usually not warranted. There are only limited data to support protein supplementation in competitive sports. There is some evidence supporting the use of creatine and possibly HMB as ergogenic aids in specific situations. Further research is needed before definitive recommendations can be made on the type, timing and effectiveness of protein supplements.
Ethiopian runners are famous for their achievements in long-distance running. The recent immigrat... more Ethiopian runners are famous for their achievements in long-distance running. The recent immigration of Ethiopians to Israel provided an opportunity to compare some physiological variables between elite Ethiopian and white Israeli runners. Six Ethiopian and five white Israeli runners, aged 20 to 40 years, were studied before and after an 11 km race. Venous blood was sampled from each runner prior to the race, and 1 h, 48 h, and 5 days following the race. The activities of creatine kinase (CK), lactate dehydrogenase (LDH) and aspartate aminotransferase (AST) were measured, and levels of serum electrolytes, urea, creatinine, phosphorus, albumin, cholesterol, and alkaline phosphatase were also determined. CK activity rose 2.6-fold with a peak 5 days after the race. LDH and AST levels rose as well (1.4-1.3-fold, respectively). Significant elevations also occurred in serum phosphorus, uric acid, and creatinine concentrations 1 h after the race. In contrast to previous studies in which higher enzyme activities were reported in blacks, we did not detect any difference in serum enzyme values between black and white runners.
Journal of Strength and Conditioning Research, 2011
A case study of virilizing adrenal tumor in an adolescent female elite tennis playerinsight into ... more A case study of virilizing adrenal tumor in an adolescent female elite tennis playerinsight into the use of anabolic steroids in young athletes.
Journal of Pediatric Gastroenterology and Nutrition, Aug 1, 2003
Polyethylene glycol solution (PEG) is a purgative solution most commonly used for bowel preparati... more Polyethylene glycol solution (PEG) is a purgative solution most commonly used for bowel preparation in both adults and children. Nasogastric infusion of PEG is considered a safe and effective means of administration when patients cannot or will not take the solution orally. Nausea, vomiting, and bloating are commonly reported adverse reactions. We present an 8-year-old girl with life-threatening respiratory failure after aspiration of PEG, which was treated successfully by bronchoalveolar lavage. CASE REPORT The patient was an 8-year-old girl with chronic abdominal pain. Two months before her current admission, she was diagnosed with fecal impaction and had a successful disimpaction with PEG solution. Because her abdominal pain had continued, the patient was admitted to a regional hospital for intestinal lavage and colonoscopy. A nasogastric tube was placed with difficulty and PEG solution was infused via the nasogastric tube. No radiographic verification of the position of the nasogastric tube was obtained. The patient subsequently vomited several times. Two hours after starting the infusion, the patient experienced difficulty breathing, chest pain, and tachypnea, which became worse during the following few hours. Oxygen saturation was 70% on room air. Respiratory rate was 50 to 70 breaths per minute. The patient was placed on supplemented oxygen therapy, up to 100% oxygen via a non-rebreathing mask. Arterial blood gas obtained while the patient was on 100% oxygen supplement showed pH 7.38, pCO 2 38 mm Hg, paO 2 93 mmHg, BE-2 and HCO3-22. Chest roentgenogram
Journal of Pediatric Endocrinology and Metabolism, 2013
Persistent hyperinsulinemic hypoglycemia of infancy (PHHI), the most common cause of persistent h... more Persistent hyperinsulinemic hypoglycemia of infancy (PHHI), the most common cause of persistent hypoglycemia in the neonatal period and infancy, is a genetic disorder characterized by abnormal regulation of insulin secretion. Octreotide, a somatostatin analog, is often used as a second-line treatment when diazoxide therapy fails to control hypoglycemia. We report herein a rare development of octreotide-induced hepatitis following prolonged treatment for PHHI in an infant. Octreotide-induced hepatitis may occur mostly when high doses are given, or when dosing is increased. This warrants routine examination of liver function. When hepatitis develops, prompt cessation of octreotide therapy will probably result in subsequent resolution.
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