Exercise Improves Insulin Sensitivity in the Absence of Changes in Cytokines.

PURPOSE: The benefits of aerobic exercise training on insulin sensitivity in subjects with the metabolic syndrome (MetS) are, at least in part, associated with changes in cytokines. Recent studies identified novel cytokines (e.g. fractalkine, omentin and osteopontin) that are strongly involved in glucose homeostasis and therefore potentially contribute in the exercise-induced changes in insulin sensitivity. Therefore, we aim to examine changes in skeletal muscle RNA expression and plasma levels of novel cytokines after exercise training, and correlate these changes to the exercise-induced changes in insulin sensitivity. METHODS: Women with the metabolic syndrome (MetS, n=11) and healthy women (n=10) participated in a 6-month aerobic exercise training intervention (3/week, 45min per session at 65%-85% of individual heart rate reserve). Before and after training, we examined insulin sensitivity (M-value during hyperinsulinemic euglycaemic clamp), circulating blood levels of cytokines (venous blood sample; leptin, adiponectin, omentin, fraktalkin, osteopontin). Skeletal muscle RNA-expression of these cytokines (muscle biopsy) was examined in two subgroups (MetS n=6; healthy women n=6). RESULTS: At baseline, plasma levels of omentin (85.8±26.2ng/ml) and adiponectin (5.0±1.7μg/ml) levels were significantly higher in controls compared to MetS (51.1±27.1; 3.6±1.1 respectively), and leptin levels were lower in controls (18.7±11.5ng/ml vs 53.0±23.5). M-value was significantly higher in controls (8.1±1.9mg/kg/min) than in MetS (4.0±1.7). Exercise training significantly improved M-values in both groups (P0.05). CONCLUSION: Whilst exercise training successfully improves insulin sensitivity in MetS and healthy women, we found no change in plasma and mRNA expression levels of novel cytokines

Post-exercise rehydration: Effect of consumption of beer with varying alcohol content on fluid balance after mild dehydration

Purpose: The effects of moderate beer consumption after physical activity on rehydration and fluid balance are not completely clear. Therefore, in this study we investigated the effect of beer consumption, with varying alcohol content, on fluid balance after exercise-induced dehydration.Methods: Eleven healthy males were included in this cross over study (age 24.5 ± 4.7 yrs, body weight 75.4 ± 3.3 kg, VO2max 58.3 ± 6.4 mL · kg · min-1). Subjects exercised on a cycle ergometer for 45 min at 60 % of their maximal power output (Wmax) until mild dehydration (1 % body mass loss). Thereafter, in random order, one of five experimental beverages was consumed, in an amount equal to 100% of their sweat loss: non-alcoholic beer (0.0 %), low-alcohol beer (2.0 %), full-strength beer (5.0 %), an isotonic sports drink and water. Fluid balance was assessed up till 5 hours after rehydration.Results: After 1 hour, urine production was significantly higher for 5 % beer compared to the isotonic sports drink (299 ± 143 mL vs 105 ± 67 mL; p < 0.01). At the end of the 5 h observation period net fluid balance (NFB) was negative for all conditions (p = 0.681), with the poorest fluid retention percentage for 5 % beer (21 % fluid retention) and the best percentage for the isotonic sports drink (42 %). Non-alcoholic beer, low-alcoholic beer and water resulted in fluid retention of 36 %, 36 % and 34 % respectively (p = 0.460). Conclusions: There was no difference in NFB between the different beverages. Only a short-lived difference between full-strength beer and the isotonic sports drink in urine output and NFB was observed after mild exercise-induced dehydration. Fluid replacement – either in the form of non-alcoholic beer, low-alcoholic beer, full-strength beer, water or an isotonic sports drink of 100 % of body mass loss was not sufficient to achieve full rehydration. The combination of a moderate amount of beer, with varying alcohol content, enough water or electrolyte- and carbohydrate beverages, and salty foods might improve rehydration, but more research is needed

Effects of Likeness and Synchronicity on the Ownership Illusion over a Moving Virtual Robotic Arm and Hand

In this study we investigated body ownership over a virtual hand and arm as a function of their visual appearance (likeness) and synchronicity of visuo-tactile stimulation with a virtual electric toothbrush and a vibrotactile glove. In all conditions, participants controlled the movement of arm and fingers, maintaining synchronicity in motor-proprioceptive-visual signals. While the effects of varying likeness and temporal synchronicity of visual and haptic stimuli on the ownership illusion have both been investigated individually before, their relative contribution is still unknown. We find that likeness should be complete: making only the hand robotic reduces the subjective ownership illusion to same level as that of a full robotic arm and hand. Visuo-tactile synchronicity is not a hard prerequisite for an ownership illusion to occur: a high degree of agency with congruent motor-proprioceptive-visual cues and an arm/hand layout similar to one's own body can be sufficiently strong to overrule incongruent visuo-tactile cues. This work is part of a larger study on the relative contribution of factors such as likeness, viewing mode, tactile stimulation and degree of agency on the body ownership illusion. The results may contribute to the enhancement of dexterous performance in remote telemanipulation tasks

Cooling vests alleviate perceptual heat strain perceived by COVID-19 nurses

Cooling vests alleviate heat strain. We quantified the perceptual and physiological heat strain and assessed the effects of wearing a 21°C phase change material cooling vest on these measures during work shifts of COVID-19 nurses wearing personal protective equipment (PPE). Seventeen nurses were monitored on two working days, consisting of a control (PPE only) and a cooling vest day (PPE + cooling vest). Sub-PPE air temperature, gastrointestinal temperature (T(gi)), and heart rate (HR) were measured continuously. Thermal comfort (2 [1–4] versus 1 [1–2], p(condtition) < 0.001) and thermal sensation (5 [4–7] versus 4 [2–7], p(condition) < 0.001) improved in the cooling vest versus control condition. Only 18% of nurses reported thermal discomfort and 36% a (slightly) warm thermal sensation in the cooling vest condition versus 81% and 94% in the control condition (OR (95%CI) 0.05 (0.01–0.29) and 0.04 (<0.01–0.35), respectively). Accordingly, perceptual strain index was lower in the cooling vest versus control condition (5.7 ± 1.5 versus 4.3 ± 1.7, p(condition) < 0.001, respectively). No differences were observed for the physiological heat strain index T(gi) and rating of perceived exertion across conditions. Average HR was slightly lower in the cooling vest versus the control condition (85 ± 12 versus 87 ± 11, p(condition) = 0.025). Although the physiological heat strain among nurses using PPE was limited, substantial perceptual heat strain was experienced. A 21°C phase change material cooling vest can successfully alleviate the perceptual heat strain encountered by nurses wearing PPE

Effectiveness of collagen supplementation on pain scores in healthy individuals with self-reported knee pain: a randomized controlled trial

The purpose of this study was to examine the effects of 12 weeks collagen peptide (CP) supplementation on knee pain and function in individuals with self-reported knee pain. Healthy physically active individuals (n = 167; aged 63 [interquartile range = 56–68] years) with self-reported knee pain received 10 g/day of CP or placebo for 12 weeks. Knee pain and function were measured with the Visual Analog Scale (VAS), the Lysholm questionnaire, and the Knee injury and Osteoarthritis Outcome Score (KOOS). Furthermore, we assessed changes in inflammatory, cartilage, and bone (bio)markers. Measurements were conducted at baseline and after 12 weeks of supplementation. Baseline VAS did not differ between CP and placebo (4.7 [2.5–6.1] vs. 4.7 [2.8–6.2], p = 0.50), whereas a similar decrease in VAS was observed after supplementation (−1.6 ± 2.4 vs. −1.9 ± 2.6, p = 0.42). The KOOS and Lysholm scores increased after supplementation in both groups (p values 0.05). A reduced knee pain and improved knee function were observed following supplementation, but changes were similar between groups. This suggests that CP supplementation over a 12-week period does not reduce knee pain in healthy, active, middle-aged to elderly individuals. Novelty CP supplementation over a 12-week period does not reduce knee pain in healthy, active, middle-aged to elderly individuals. CP supplementation over a 12-week period does not impact on inflammatory, cartilage, and bone (bio)markers in healthy, active, middle-aged to elderly individuals.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author

Subject characteristics (N = 12).

<p>Values are mean ± standard deviation. HR  =  heart rate, BMI  =  body mass index, VO2MAX  =  maximum oxygen uptake, VO2Peak  =  peak oxygen uptake, Wmax  =  maximum work load.</p

Top 20 of most highly induced genes in exercising and non-exercising leg.

<p>A) Left panel shows the top 20 of upregulated genes in the exercising leg (N = 9), right panel the corresponding genes in the non-exercising leg. B) Left panel shows the top 20 of upregulated genes in the non-exercising leg (N = 7), right panel the corresponding genes in the exercising leg. Green is a signal log ratio of −3, red a signal log ratio of 3. Values are displayed per subject to visualize inter-individual differences. FC = fold change, *  = p<0.05, ^#  = p<0.1 between exercising and non-exercising leg.</p

Exercise increases heart rate and plasma levels of FFA, insulin, cortisol and noradrenaline.

<p>Heart rate reserve (%) was calculated based on the heart rate measured during the exercise (N = 12). Plasma glucose, triglyceride, free fatty acids, lactate, insulin, cortisol, adrenaline and noradrenaline were measured before and after exercise (T0 and T1; N = 12) and after 2 hours of recovery (T3; N = 12). a = p<0.05 compared to T0, b = p<0.5 compared to T3, c = p<0.1 compared to T0, p<0.1 compared to T3, repeated measures ANOVA. Depicted is mean ± SEM.</p

Exercise mainly causes upregulation of gene expression in both the exercising and non-exercising leg.

<p>(A) Venn diagram of significantly regulated genes and their overlap. (B) Flowchart of microarray analysis. Heatmaps of all significant genes in the non-exercising (C) and exercising leg (D) N = 9, IQR  =  interquartile range.</p

Induction of transcription factor pathways by exercise.

<p>Transcription factor pathways related to growth, stress response, cAMP signalling and hypoxia were induced by exercise. Transcription factor pathways were identified for the exercising leg using IPA and are displayed in a bar diagram. Genes induced by exercise for the different transcription factors can be found in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0051066#pone.0051066.s005" target="_blank">table S1</a>. Transcription factors with a z-score above 1.5 (or under −1.5) are considered as biologically relevant.</p