The adaptive effects of exercise-induced inflammation and reactive oxygen species production has been well studied in adults, but not in children. Characterizing the exercise responses in children compared with adults will start clarifying the transition from the child phenotype to that of an adult. Ten children aged 8–10 and 12 adults aged 19–21 performed 2 × 30-min bouts of continuous cycling, separated by a 6-min rest period, at a target work rate of 60% of their maximum aerobic capacity. Blood samples were collected pre- and immediately postexercise, and analyzed for neutrophil count, systemic oxidative and inflammatory markers, and intracellular neutrophil-derived reactive oxygen species. Although postexercise absolute neutrophils increased by approximately twofold in men (2.72 ± 0.49 × 109/L to 4.85 ± 2.05 × 109/L; p = .007), boys showed no such change (3.18 ± 0.67 × 109/L to 3.57 ± 0.73 × 109/L; p = .52). Contrary to these findings, boys did show an increase in overall intracellular neutrophil ROS production, whereas men did not. Boys also demonstrated higher overall protein carbonyl levels (0.07 nmol/mg vs 0.04 nmol/mg; boys vs men respectively), whereas men showed higher overall malondialdehyde (0.24 μM vs 0.67 μM; boys vs men respectively). The differences observed in the exercise-induced inflammatory and oxidative stress response may indicate growth-mediated adaptive responses to exercise during childhood development.
Maple Liu, Linda J. Gillis, Nicholas R. Persadie, Stephanie A. Atkinson, Stuart M. Phillips and Brian W. Timmons
There is some evidence that a combination of factors can reduce inflammation and associated metabolic risk factors. We studied the early cardiometabolic and inflammatory adaptations to a short-term exercise intervention with and without milk in obese adolescents. Fifty-four adolescents were randomized to consume milk post exercise (MILK) or a carbohydrate beverage (CONT) during one-week of daily exercise. Insulin levels were not different between the groups post training. Glucose was reduced over time in both groups (-9 ± 13 mg/dl MILK and -6 ± 14 mg/dl CONT, p < .05) but not different between groups. There was a greater decrease in mean arterial pressure (MAP) in the MILK group (-3 ± 6 mmHg MILK vs. 2 ± 7 mmHg CONT, p < .04). Milk provided postexercise did not affect C-reactive protein (CRP), tumor necrosis factor-α (TNF-α) or interleukin-6 (IL-6). The exercise intervention led to an increase in TNF-α in both groups (0.27 ± 0.7 pg/ml MILK and 0.48 ± 0.6 pg/ml CONT, p < .001). The early adaptations to a short-term exercise intervention in obese adolescents include a reduction in MAP and an increase in some inflammatory markers.
Irena Auersperger, Bojan Knap, Ales Jerin, Rok Blagus, Mitja Lainscak, Milan Skitek and Branko Skof
Exercise-associated iron deficiency is a common disorder in endurance athletes. The authors investigated the effects of long-term endurance exercise on hepcidin concentrations, inflammatory parameters, and iron status in moderately trained female long-distance runners. Eighteen runners were assigned to either an interval- or a continuous-training exercise group. The physical training consisted of two 3-week progressive overload periods, each followed by a week’s recovery, and concluded with a 10- or 21-km competitive run. Samples were taken 6 times during the 8-wk training program, first at baseline (BPre), then after the first and second 3-wk training loads (TPost1, TPost2), after each recovery week (Recovery1 and Recovery2), and poststudy (BPost). Soluble transferrin receptor (sTfR) concentrations were increased in Recovery2 and BPost compared with BPre (p = .02), hemoglobin decreased in TPost1 and TPost2 (p < .001), and red blood cells decreased in TPost2 (p = .01). Hepcidin decreased with time in TPost1 and in BPost compared with BPre (p < .001) and increased in TPost2 compared with TPost1 (p < .001). No differences over time were found for high-sensitivity C-reactive protein. The main findings of the current study indicate that serum hepcidin and sTfR were affected after 8 weeks of endurance running in women. No positive relation was found with inflammation.
Mette S. Nielsen, Jonas S. Quist, Jean-Philippe Chaput, Stine-Mathilde Dalskov, Camilla T. Damsgaard, Christian Ritz, Arne Astrup, Kim F. Michaelsen, Anders Sjödin and Mads F. Hjorth
Inflammatory markers, adiponectin, and movement/nonmovement behaviors have all been linked to risk factors for cardiovascular disease; however, the association between childhood movement/nonmovement behaviors and inflammatory markers and adiponectin is unknown.
We explored the association between accelerometer determined moderate-to-vigorous physical activity (MVPA), sedentary time, and sleep (7 days/8 nights) and fasting C-reactive protein (CRP), interleukin-6 (IL-6), and adiponectin in 806 school children. A sleep variability score was calculated.
MVPA was negatively associated with adiponectin in boys and girls (P < .001) and with CRP and IL-6 in girls (P < .05) independent of sleep duration, sedentary time, age, fat mass index (FMI), and pubertal status. Sedentary time was positively associated with adiponectin in boys and girls (both P < .001), and sleep duration with adiponectin in boys independent of age, FMI, and pubertal status (P < .001); however, these associations disappeared after mutual adjustments for movement behavior. Sleep duration variability was positively associated with CRP in girls independent of all covariates (P < .01).
MVPA remained negatively associated with inflammatory markers and adiponectin, and sleep duration variability positively associated with CRP after adjustment for FMI, pubertal status, and other movement behavior. The inverse association between MVPA and adiponectin conflicts with the anti-inflammatory properties of adiponectin.
Gina Many, Maria-Eugenia Hurtado, Charles Tanner, Joseph Houmard, Heather Gordish-Dressman, Jung-Jun Park, Gabriel Uwaifo, William Kraus, James Hagberg and Eric Hoffman
We initiated a pilot study to investigate the effects of 8 wks of aerobic exercise training (ET) on insulin sensitivity and inflammatory markers in obese and insulin-resistant minority adolescents. Eleven morbidly obese (BMI 41.4 ± 1.8 kg/m2) minority adolescents were entered into a supervised ET intervention (~180 min/wk at 40–55%VO2PeakR [(VO2Peak − VO2Rest)/VO2Rest]). The effects of training on insulin sensitivity (SI), inflammation and other metabolic syndrome features were examined. Results: Insulin action improved in response to training, as indicated by a ~37% increase in SI (p = .018). Plasma levels of several proinflammatory cytokines were reduced in response to ET, as indicated by significant decrements in sTNF-R, CCL2, MPO, IL-6, resistin, and leptin, with no significant changes in hsCRP. ET induced reductions in BMI and percent total body fat. Conclusions: The present study supports the efficacy of ET interventions on metabolic syndrome features in morbidly obese minority youth.
Nosotros iniciamos un estudio piloto para investigar los efectos de 8 semanas de entrenamiento con ejercicios aeróbicos (EA) sobre la sensibilidad insulinica y los marcadores inflamatorios en un grupo minoritario de adolescentes abesos con resistencia a lá insulina. Once adolescentes con obesidad mórbida (IMC 41, 4+1.8kg/m2) fueron asignados a un grupo de intervención que realizo un EA supervisado (~180 min/semana al 40-55%VO2 picoR [(VO2Pico − VO2Reposo)/VO2Reposo]). Se analizo el efecto del entrenamiento sobre la sensibilidad insulinica (IS), inflamación y otras características del síndrome metabòlico. RESULATDOS: El incremento del 37% en la SI (p = 0.018) indico que La acción de la insulina mejora en respuesta al entrenamiento. Como indican la disminución significativa de sTNF-R, CCL2, MPO, IL-6, resistina, and leptina, y la falta de cambios significativos en hsCR, los niveles plasmáticos de varias citoquinas proinflamatorias se redujeron en respuesta al EA. Además, el entrenamiento produjo una reducción del IMC y del porcentaje de grasa corporal. CONCLUSIONES: Los resultados del presente estudio apoyan la eficacia de una intervención con EA sobre las características del síndrome metabólico en un grupo minoritario de adolescentes con obesidad mórbida.
Samantha K. Gill, Dean M. Allerton, Paula Ansley-Robson, Krystal Hemmings, Martin Cox and Ricardo J.S. Costa
The study aimed to determine if short-term high dose probiotic supplementation containing Lactobacillus casei (L.casei) attenuates the commonly reported exertional-heat stress (EHS) induced endotoxinaemia and cytokinaemia. Eight endurance trained male volunteers (mean± SD: age 26 ± 6 y, nude body mass 70.2 ± 8.8 kg, height 1.75 ± 0.05 m, VO2max 59 ± 5 ml·kg-1·min-1) completed a blinded randomized cross-over design, whereby oral ingestion of a commercially available probiotic beverage containing L.casei (volume equivalent for ×1011 colony forming units·day-1) (PRO) or placebo (PLA) was consumed for 7 consecutive days before exposure to EHS, which comprised of 2h running exercise at 60% VO2max in hot ambient conditions (34.0 °C and 32% RH). Blood samples were collected at baseline (7 days before EHS), pre-EHS, post-EHS (1 hr, 2 hr, 4 hr, and at 24 hr). Plasma samples were analyzed for gram-negative bacterial endotoxin, cytokine profile (IL-6, IL-1β, TNF-α, IFN-γ, IL-8, and IL-10) and plasma osmolality. Plasma osmolality did not differ between trials. Seven days of L.casei supplementation did not show significant changes in resting circulatory endotoxin concentration or plasma cytokine profile compared with PLA. A main effect of time was observed for IL-6, TNF-α, IL-10 and IL-8; whereby levels increased in response to EHS (p < .05). Relative to pre-EHS concentrations, higher plasma concentrations of endotoxin (p = .05), and a trend for higher plasma TNF-α concentration (p = .09) was observed on PRO compared with PLA throughout recovery. Short-term high dose supplementation of a probiotic beverage containing L.casei before EHS did not attenuate EHS induced endotoxaemia and cytokinaemia; nor is it more positively favorable over a placebo.
Ken R. Mautner
Column-editor : Tracy Ray
Francisco J. Ordonez, Gabriel Fornieles-Gonzalez, Alejandra Camacho, Miguel A. Rosety, Ignacio Rosety, Antonio J. Diaz and Manuel Rosety-Rodriguez
Recent studies have reported that obese young people with Down syndrome suffer from low-grade systemic inflammation. Whereas this condition may be improved in the general population by regular exercise, the problem has received no attention in the case of people with intellectual disability. Therefore, the authors’ aim was to assess the influence of aerobic training on plasma adipokines in obese women with Down syndrome. Twenty obese young women with Down syndrome volunteered for this study, 11 of whom were randomly assigned to a 10-wk aerobic-training program. They attended 3 sessions/wk, which consisted of warm-up exercises followed by the main activity on a treadmill (30–40 min) at a work intensity of 55–65% of peak heart rate and ended with a cooling-down period. The control group included 9 women with Down syndrome matched for age, sex, and body-mass index. Fat-mass percentage and distribution were measured, and plasma adipokine levels (leptin and adiponectin) were assessed. In addition, each participant performed a maximal graded continuous treadmill exercise test. These parameters were assessed pre- and postintervention. Aerobic training produced a significant increase in participants’ maximal oxygen uptake (20.2 ± 5.8 vs.23.7 ± 6.3 ml · kg−1 · min−1; p < .001), and plasma leptin levels were significantly reduced in the intervention group (54.2 ± 6.7 vs.45.7 ± 6.1 ng/ml; p = .026). Further significant correlations between plasma leptin and indices of obesity were found. In contrast, no significant changes were found in adiponectin levels (p > .05). None of the tested parameters changed in the control group. In conclusion, a 10-week training program reduced leptin levels in obese young women with Down syndrome.
Anna Skarpanska-Stejnborn, Lucja Pilaczynska-Szczesniak, Piotr Basta, Ewa Deskur-Smielecka, Donata Woitas-Slubowska and Zdzislaw Adach
The aim of this study was to investigate the effect of plant superoxide dismutase extract (GliSODin) supplementation on the balance of oxidants and antioxidants in the serum and erythrocytes of competitive rowers. The double-blinded study included 19 members of the Polish rowing team who were participating in a preparatory camp. Subjects were randomly assigned to the supplemented group (n = 10), who received 2 capsules (500 mg) of GliSODin extract once daily for 6 weeks, or the placebo group (n = 9). At the beginning and end of the study, subjects performed a 2,000-m maximum-effort test on a rowing ergometer. Blood samples were taken from the antecubital vein before each exercise test, 1 min after completing the test, and after a 24-hr restitution period. The following redox parameters were assessed in erythrocytes: superoxide dismutase (SOD) activity, glutathione peroxidase activity, and concentrations of thiobarbituric-acid-reactive substances. In addition, creatine kinase activity and total antioxidant capacity were measured in plasma samples, lactate levels were determined in capillary blood samples, and C-reactive protein and lactate dehydrogenase concentrations were measured in serum. After supplementation, SOD activity was significantly higher (p = .0037) in the supplemented group than the placebo group, and C-reactive protein was significantly (p = .00001) lower in athletes receiving GliSODin than those in the placebo group. In conclusion, supplementation with an extract rich in SOD activity promoted antioxidant status and protected against increased inflammation in the serum of professional rowers but had no effect on oxidative damage induced by exhaustive exercise.