Acute effects of high- and low-intensity exercise bouts on leukocyte counts.

BACKGROUND/OBJECTIVE: It is widely accepted that physical exercise may bring about changes in the immune system. Even acute bouts of exercise can alter the number and function of leukocytes, but the degree of white blood cell trafficking depends on the intensity and duration of exercise. The aim of this study was to analyze the acute and short-term effects of exercise intensity on leukocyte counts and leukocyte subsets. METHODS: Nine physically healthy, active young males (21.0 ± 1.9 years) underwent three experimental trials: high exercise intensity [80% peak oxygen consumption (VO2peak)], low exercise intensity (40% VO2peak), and the control condition (no exercise). Blood samples were collected prior to exercise, immediately after exercise, and 2 hours after exercise. Two-way analysis of variance for repeated measures was used to evaluate differences between the trials and the time-points, and to compare times within trials. RESULTS: There was a greater increase in the leukocyte count after high-intensity exercise, compared to the control condition (p < 0.01) and low-intensity exercise (p < 0.01). This effect was still present 2 hours after passive recovery (p < 0.01). CONCLUSION: When the same participants were submitted to different exercise intensities, the acute and short-term effects of exercise on white blood cells were intensity-dependent immediately after exercise (i.e., lymphocytosis and monocytosis) and 2 hours after passive recovery (i.e., neutrophilia).

Relationship between lipid and hematological profiles with adiposity in obese adolescents.

BACKGROUND: An excess of weight including obesity have reached epidemic rates in all age groups, both in developed and developing countries. It is notable that overweight children and adolescents have a higher likelihood of becoming obese adults and to present health-related problems early in life. OBJECTIVES: [corrected] To verify associations of the lipid and hematological profiles with adiposity in obese adolescents beginning multidisciplinary weight loss therapy. METHODS: This cross-sectional study was conducted with 85 adolescents of both genders, aged 12-19 years (Tanner staging 3 or 4) and body mass index greater than the 95(th) percentile. The sum of the triceps, subscapular and calf skinfolds and the waist circumference were used to estimate adiposity. Blood samples were collected from all patients after overnight fasting to analyze blood lipids (total cholesterol, high-density lipoprotein, low-density lipoprotein, very low-density lipoprotein and triglycerides), blood sugar and the hematological profile (hemoglobin, platelets and red blood cells). The Kolmogorov-Smirnov test and Spearman and Pearson correlation coefficients were used for statistical analysis with significance set for p-values ≤ 0.05. RESULTS: There were statistical differences between genders for red blood cells (p-value = 0.000), hemoglobin (p-value = 0.000) and platelets (p-value = 0.002). Positive correlations were found for red blood cells (p-value = 0.031) and hemoglobin (p-value = 0.024) with waist circumference. There was a negative correlation between hemoglobin and the sum of skinfolds (p-value = 0.022). CONCLUSION: The results demonstrate an association between the lipid and hematological profiles and body adiposity in obese adolescents thus reinforcing the importance of treating obese adolescents early to prevent health related problems in adult life.

Relationship between lipid and hematological profiles with adiposity in obese adolescents

Background: An excess of weight including obesity have reached epidemic rates in all age groups, both in developed and developing countries. It is notable that overweight children and adolescents have a higher likelihood of becoming obese adults and to present health-related problems early in life. Objetives: To verify associations of the lipid and hematological profiles with adiposity in obese adolescents beginning multidisciplinary weight loss therapy. Methods: This cross-sectional study was conducted with 85 adolescents of both genders, aged 12-19 years (Tanner staging 3 or 4) and body mass index greater than the 95th percentile. The sum of the triceps, subscapular and calf skinfolds and the waist circumference were used to estimate adiposity. Blood samples were collected from all patients after overnight fasting to analyze blood lipids (total cholesterol, high-density lipoprotein, low-density lipoprotein, very low-density lipoprotein and triglycerides), blood sugar and the hematological profile (hemoglobin, platelets and red blood cells). The Kolmogorov-Smirnov test and Spearman and Pearson correlation coefficients were used for statistical analysis with significance set for p-values ≤ 0.05. Results: There were statistical differences between genders for red blood cells (p-value = 0.000), hemoglobin (p-value = 0.000) and platelets (p-value = 0.002). Positive correlations were found for red blood cells (p-value = 0.031) and hemoglobin (p-value = ...

Acute effects of aerobic exercise on mood and hunger feelings in male obese adolescents: a crossover study.

BACKGROUND: The aim of this study was to determine the acute effects of exercise intensity on anxiety, mood states and hunger in obese adolescents. METHODS: Subjects were eight male obese adolescents (age 15.44 ± 2.06 y; BMI 33.06 ± 4.78 kg/m2). Each subject underwent three experimental trials: (1) Control, seated for 30 min; (2) Low intensity exercise (LIE)--exercise at 10% below ventilatory threshold (VT); (3) High intensity exercise (HIE)--exercise at 10% above VT. Anxiety (STAI Trait/State), mood (POMS) and hunger (VAS) were assessed before and immediately after the experimental sessions. Comparisons between trials and times were assessed using Kruskal-Wallis and Wilcoxon tests, respectively. Associations between variables were described using a Spearman test. RESULTS: The largest increase in hunger was observed after LEI (914.22%). Both exercise sessions increased anxiety, fatigue and decreased vigor (p < 0.05). CONCLUSIONS: Acute exercise bouts are associated with negative changes in anxiety and mood, and with increases in hunger in obese adolescents.

Efeitos agudos de diferentes intensidades de exercício sobre a ingestão alimentar pós-exercício / Acute effects of exercise intensity on pos-exercise food intake in young men

O objetivo do presente estudo foi verificar os efeitos agudos de diferentes intensidades de exercício aerróbio (40 e 80 por cento do VO2pico) sobre a ingestão alimentar pós-exercício. Participaram do estudo 18 adultos jovens, eutróficos (22,20 ± 1,72 kg/m²) e fisicamente ativos. Todos os sujeitos foram submetidos aleatoriamente a três condições experimentais: controle (sem exercício); EBI, exercício de baixa intensidade (40 por cento doVO2pico) e EAI, exercício de alta intensidade (80 por cento do VO2pico). As sessões de exercício foram isocalróricas (350 kcal). Após 120 minutos de recuperação passiva, os voluntários tinham livre acesso a um "buffet" variado de alimentos, a ingestão alimentar foi determinada atravéz da pesagem dos alimentos ingeridos. Os dados alimentares obtidos foram então tabulados e analisados por meio do "software" Nutwin 6.0 (UNIFESP, 2002), para estimativa do consumo energético total (kcal) e ingestão dos macronutrientes (carboidratos, proteínas e lipídeos) em gramas. Os resultados não demonstram nenhuma diferença na ingesto alimentar entre as condições experimentais analisadas. Dessa forma, podemos concluir que a ingestão alimentar pós-exercício não se mostrou dependente da intensidade do esforóo em curto prazo em indivíduos adultos jovens fisicamente ativos.

The aim of this study was to investigate the acute effects of different aerobic exercise intensities (40 and 80 percent do VO2peak) on post-exercise food intake. The sample was composed of eighteen healthy, physically active young men, of normal weight (22.20 ± 1.72 kg/m²). Subjects were randomly submitted to three experimental conditions: control (no exercise); low-intensity exercise (LIE -40 percent of VO2peak) and high-intensity exercise (HIE- 80 percent of VO2peak). Exercise trials were iso-caloric (350 Kcal). After 120 minutes of passive recovery, the volunteers had free access to a variety food buffet, and food intake was determined thru food weight. Data was analyzed by the software Nutwin 6.0 (UNIFESP, 2002) to estimate total energy intake (kcal) and consumption of the macronutrients (carbohydrates, proteins and lipids). The results suggest that food intake after exercise showed no significant differences between the experimental conditions. In conclusion, food intake after exercise is not dependent on exercise intensity in healthy young men.

Efeitos de diferentes intensidades de exercício sobre o gasto energético e a sensação de fome em jovens / Effects of different exercise intensities on energy expenditure and hunger sensation in young adults

O presente estudo objetiva investigar os efeitos agudos e de curto prazo (2 horas) de diferentes intensidades de exercício aeróbio sobre o gasto energético pós-exercício, a razão de troca respiratória (QR) e a sensação de fome em homens. Participaram do estudo, 20 sujeitos eutróficos (22,41±1,76 kg/m²) e praticantes de exercício físico. Todos os sujeitos foram submetidos, aleatoriamente, a quatro condições experimentais: controle (sem exercício); EBI, exercício de baixa intensidade (40% do VO2pico); EMI, exercício de moderada intensidade (60% do VO2pico) e EAI, exercício de alta intensidade (80% do VO2pico). A magnitude do(EPOC - consumo excessivo de oxigênio após o exercício) e o comportamento do QR foram mensurados através de análise direta de gases. A escala visual analógica foi utilizada para avaliar a sensação de fome em (basal, imediatamente após a sessão experimental, aos 30,60, 90 e 120 minutos de recuperação passiva). Os resultados demonstraram que o EPOC teve uma correlação positiva com a intensidade do exercício (r=0,74, p<0,01), sendo a duração e a magnitude dependentes da intensidade do exercício. Entre todas as condições experimentais, a sensação de fome ao término do exercício foi maior no EBI (p <0,01). Ao longo do período de 120 minutos de recuperação passiva, a sensação de fome aumentou independente da condição experimental. A partir dos resultados, podemos sugerir que apóso EAI a magnitude do EPOC é maior, promovendo maior gasto energético no pós-exercício, com um concomitante aumento na utilização de gordura (menor QR) e supressão transitória da sensação de fome em adultos jovens.

The aim of this study was to investigate the acute and short-term effects of different aerobic exercise intensities on postexercise energy expenditure, respiratory exchange ratio (RER), and hunger sensation in young adults. Twenty healthy, physically active (>6 months) young menof normal weight (22.41±1.76 kg/m²) participated in this study. All subjects were randomly submitted to four experimental conditions: control (no exercise); LIE, low-intensity exercise (40% of VO2peak); MIE, exercise of moderate intensity (60% of VO2peak), and HIE, high-intensity exercise(80% of VO2peak). The magnitude of (EPOC - excess post-exercise oxygen consumption), and RER were measured by direct gas analysis. A visual analogue scale was used to rate hunger sensation at baseline, immediately after the experimental session, and after 30, 60, 90 and 120minutes of passive recovery. The results showed a positive correlation between the magnitude of EPOC and exercise intensity (r=0.74, p<0.01), with the duration and magnitude depending on exercise intensity. For all experimental conditions, the hunger sensation was greater in theLIE group (p<0.01). The hunger scores increased over the 120 minutes of passive recovery in all exercise and control sessions. The results suggest that the magnitude of EPOC is higher after HIE, promoting higher postexercise energy expenditure and a concomitant increase in fat utilization (lower RER) and transient suppression of hunger sensation in young adults.