Aerobic Cycling Training Research Articles

Brain-Derived neurotrophic factor and inflammatory biomarkers are unaffected by acute and chronic intermittent hypoxic-hyperoxic exposure in geriatric patients: a randomized controlled trial

Background Animal and human studies have shown that exposure to hypoxia can increase brain-derived neurotrophic factor (BDNF) protein transcription and reduce systematic inflammatory cytokine response. Therefore, the aim of this study was to investigate the acute and chronic effects of intermittent hypoxic-hyperoxic exposure (IHHE) prior to aerobic exercise on BDNF, interleukin-6 (IL-6), and C-reactive protein (CRP) blood levels in geriatric patients. Patients and Methods Twenty-five geriatric patients (83.1 ± 5.0 yrs, 71.1 ± 10.0 kg, 1.8 ± 0.9 m) participated in a placebo-controlled, single-blinded trial and were randomly assigned to either an intervention (IG) or control group (CG) performing an aerobic cycling training (17 sessions, 20 min·session−1, 3 sessions·week−1). Prior to aerobic cycling exercise, the IG was additionally exposed to IHHE for 30 min, whereas the CG received continuous normoxic air. Blood samples were taken immediately before (pre-exercise) and 10 min (post-exercise) after the first session as well as 48 h (post-training) after the last session to determine serum (BDNFS) and plasma BDNF (BDNFP), IL-6, and CRP levels. Intervention effects were analyzed using a 2 x 2 analysis of covariance with repeated measures. Results were interpreted based on effect sizes with a medium effect considered as meaningful (ηp 2 ≥ 0.06, d ≥ 0.5). Results CRP was moderately higher (d = 0.51) in the CG compared to the IG at baseline. IHHE had no acute effect on BDNFS (ηp 2 = 0.01), BDNFP (ηp 2 < 0.01), BDNF serum/plasma-ratio (ηp 2 < 0.01), IL-6 (ηp 2 < 0.01), or CRP (ηp 2 = 0.04). After the 6-week intervention, an interaction was found for BDNF serum/plasma-ratio (ηp 2 = 0.06) but not for BDNFS (ηp 2 = 0.04), BDNFP (ηp 2 < 0.01), IL-6 (ηp 2 < 0.01), or CRP (ηp 2 < 0.01). BDNF serum/plasma-ratio increased from pre-exercise to post-training (d = 0.67) in the CG compared to the IG (d = 0.51). A main effect of time was found for BDNFP (ηp 2 = 0.09) but not for BDNFS (ηp 2 = 0.02). Within-group post-hoc analyses revealed a training-related reduction in BDNFP in the IG and CG by 46.1% (d = 0.73) and 24.7% (d = 0.57), respectively. Conclusion The addition of 30 min IHHE prior to 20 min aerobic cycling seems not to be effective to increase BDNFS and BDNFP or to reduce IL-6 and CRP levels in geriatric patients after a 6-week intervention. The study was retrospectively registered at drks.de (DRKS-ID: DRKS00025130).

Rapid recovery in a patient with severe COVID-19 after a low-load, high-frequency rehabilitation program using an ergometer in the supine position.

Background Rehabilitation therapy for patients with severe coronavirus disease 2019 (COVID-19) is crucial; however, studies regarding rehabilitation strategies for intensive care unit (ICU) patients with COVID-19 are limited. We report a case of severe COVID-19 in an ICU patient whose physical function and basic movement ability rapidly improved after the initiation of active aerobic exercise in the supine position.Case A 70-year-old man with hypertension and obesity was admitted to the ICU and managed with a ventilator because of severe COVID-19. Physical therapy started on postadmission day 34. Problems encountered during physical therapy included low saturation of percutaneous oxygen (SpO2; <90%), dyspnea with a light exercise load, advancing muscle weakness, and endurance decline. The rehabilitation program included getting out of bed and resistance training of the upper and lower limbs twice daily while maintaining SpO2 at ≥90%. After ventilator weaning, we initiated aerobic training using a supine ergometer with varying load volume. On discharge from the ICU on postadmission day 45, the patient' s physical function (handgrip strength, Medical Research Council score, and Borg scale) and basic movement ability (Functional Status Score for ICU) rapidly improved.Conclusion Rehabilitation therapy involving aerobic cycling training based on a quantitative load setting may be effective in treating COVID-19.

Effectiveness of physical activity interventions on reducing perceived fatigue among adults with chronic conditions: a systematic review and meta-analysis of randomised controlled trials

Fatigue is barrier of physical activity participation in adults with chronic conditions. However, physical activity alleviates fatigue symptoms. This systematic review and meta-analysis aimed to (1) synthesise evidence from randomised controlled trials (RCTs) exploring the effects of physical activity interventions on fatigue reduction and (2) evaluate their effectiveness. Medline/CINAHL/EMBASE/Web of Science and Scopus were searched up to June 24th, 2023. Two reviewers independently conducted study screening and selection (RCTs), extracted data and assessed risk of bias (RoB2). Outcome was the standardised mean difference (SMD) with 95% confidence intervals in fatigue between experimental and control groups. 38 articles met the inclusion criteria. Overall, physical activity interventions moderately reduced fatigue (SMD = 0.54, p < 0.0001). Interventions lasting 2–6 weeks demonstrated a larger effect on fatigue reduction (SMD = 0.86, p < 0.00001). Interventions with 18–24 sessions showed a large effect on fatigue reduction (SMD = 0.97, p < 0.00001). Aerobic cycling and combination training interventions had a large to moderate effect (SMD = 0.66, p = 0.0005; SMD = 0.60, p = 0.0010, respectively). No long-term effects were found during follow-up. Physical activity interventions moderately reduced fatigue among adults with chronic conditions. Duration, total sessions, and mode of physical activity were identified as key factors in intervention effectiveness. Further research is needed to explore the impact of physical activity interventions on fatigue.

Blood flow restriction accelerates aerobic training-induced adaptation of {dot{text{V}}}{text{O}}_{2} kinetics at the onset of moderate-intensity exercise

It is unclear whether blood flow restriction (BFR) accelerates the adaptation of the time constant (τ) of phase II oxygen uptake ( {dot{text{V}}}{text{O}}_{2} ) kinetics in the moderate-intensity exercise domain via moderate-intensity aerobic training. Therefore, healthy participants underwent moderate-intensity [45–60% {dot{text{V}}}{text{O}}_{2} Reserve] aerobic cycle training with or without BFR (BFR group, n = 9; CON group, n = 9) for 8 weeks to evaluate {dot{text{V}}}{text{O}}_{2} kinetics during moderate-intensity cycle exercise before (Pre) and after 4 (Mid) and 8 (Post) weeks of training. Both groups trained for 30 min, 3 days weekly. BFR was performed for 5 min every 10 min by applying cuffs to the upper thighs. The τ significantly decreased by Mid in the BFR group (23.7 ± 2.9 s [Pre], 15.3 ± 1.8 s [Mid], 15.5 ± 1.4 s [Post], P < 0.01) and by Post in the CON group (27.5 ± 2.0 s [Pre], 22.1 ± 0.7 s [Mid], 18.5 ± 1.9 s [Post], P < 0.01). Notably, the BFR group’s τ was significantly lower than that of the CON group at Mid (P < 0.01) but not at Post. In conclusion, BFR accelerates the adaptation of the {dot{text{V}}}{text{O}}_{2} kinetics of phase II by moderate-intensity aerobic training.

Influence of acute and chronic intermittent hypoxic-hyperoxic exposure prior to aerobic exercise on cardiovascular risk factors in geriatric patients-a randomized controlled trial.

Background: Intermittent hypoxic-hyperoxic exposure (IHHE) and aerobic training have been proposed as non-pharmacological interventions to reduce age-related risk factors. However, no study has yet examined the effects of IHHE before aerobic exercise on cardiovascular risk factors in the elderly. Therefore, the aim of this study was to investigate the acute and chronic effects of IHHE prior to aerobic cycling exercise on blood lipid and lipoprotein concentrations as well as blood pressure in geriatric patients. Methods: In a randomized, controlled, and single-blinded trial, thirty geriatric patients (72-94years) were assigned to two groups: intervention (IG; n = 16) and sham control group (CG; n = 14). Both groups completed 6 weeks of aerobic cycling training, 3 times a week for 20min per day. The IG and CG were additionally exposed to IHHE or sham IHHE (i.e., normoxia) for 30min prior to aerobic cycling. Blood samples were taken on three occasions: immediately before the first, ∼10min after the first, and immediately before the last session. Blood samples were analyzed for total (tCh), high-density (HDL-C), and low-density lipoprotein cholesterol (LDL-C), and triglyceride (Tgl) serum concentration. Resting systolic (SBP) and diastolic blood pressure (DBP) was assessed within 1week before, during (i.e., at week two and four), and after the interventions. Results: The baseline-adjusted ANCOVA revealed a higher LDL-C concentration in the IG compared to the CG after the first intervention session (ηp 2 = 0.12). For tCh, HDL-C, Tgl, and tCh/HDL-C ratio there were no differences in acute changes between the IG and the CG (ηp 2 ≤ 0.01). With regard to the chronic effects on lipids and lipoproteins, data analysis indicated no differences between groups (ηp 2 ≤ 0.03). The repeated measures ANOVA revealed an interaction effect for SBP (ηp 2 = 0.06) but not for DBP (ηp 2 ≤ 0.01). Within-group post-hoc analysis for the IG indicated a reduction in SBP at post-test (d = 0.05). Conclusion: Applying IHHE prior to aerobic cycling seems to be effective to reduce SBP in geriatric patients after 6 weeks of training. The present study suggests that IHHE prior to aerobic cycling can influence the acute exercise-related responses in LDL-C concentration but did not induce chronic changes in basal lipid or lipoprotein concentrations.

The effect of a 9-month hybrid intradialytic exercise training program on nerve conduction velocity parameters in patients receiving hemodialysis therapy.

Neurological complications such as peripheral neuropathy are very common in the end-stage renal disease (ESRD) patients, occurring in 60-80% of this specific population. The aim of the present study was to examine whether a 9-month hybrid intradialytic exercise training program could alter motor and sensory nerve conduction study (NCS) parameters in hemodialysis population. Seventeen stable patients undergoing HD with no clinical evidence of uremic polyneuropathy were included in the study (15M/2F, 59 ± 13.7years). All patients completed a 9-month supervised exercise training program composed of both aerobic cycling and resistance training (hybrid) during HD. Functional capacity was assessed by a battery of tests, while pain levels and fatigue profile were assessed via validated questionnaires. Motor and sensory NCS on bilateral median, ulnar, peroneal and tibial nerves as well as F-wave were assessed using a full neurographic electromyography (EMG) assessment. After the 9-month exercise training intervention, exercise capacity was increased by 65% and functional capacity by an average of 40%. The neurological assessment showed that conduction velocity from tibial and peroneal nerves was improved by 3.7% and 4.2%, respectively, while tibial F-wave latency and peroneal and sural nerve distal latency were significantly improved by 4.2%, 4.9% and 10%, respectively. Fatigue and pain were improved after the exercise intervention while fatigue score was positively correlated with conduction velocity and amplitude values. The results of the current study demonstrate that 9-month hybrid exercise training induces beneficial effects on both sensory and motor NCS parameters, improving conduction velocity and F-wave latency. Improvements in neural activity were accompanied by changes in fatigue score and pain-related aspects. The parallel improvement in motor nerve conduction velocity and its correlations with functional tests supports the hypothesis that exercise could be beneficial for preventing a decline in neural function in HD patients.

Effects of multimodal training program on muscle deoxygenation in women with breast cancer: Arandomized controlled trial.

Chemotherapy and/or radiation are the most often delivered treatments to cancer patients. Usually during the adjuvant treatment, patients complain about fatigue. In addition, physical exercise during adjuvant treatment of cancer seems to have beneficial effects. The aim of this investigation was to assess the effects of multimodal aerobic and strength exercises programs on muscle deoxygenation of patients with breast cancer undergoing adjuvant chemotherapy treatment. Thirty-two women with breast cancer (20 patients as the training group and 12 patients as the control group) undergoing adjuvant chemotherapy participated in the study. The training group took part in 6 weeks of supervised intermittent aerobic cycling, home-based walking, isometric and electrical muscle stimulation (EMS) exercise training programs. The Outcome measures were muscle deoxygenation (ΔHHb), Maximal Voluntary isometric Contraction (MViC) and Endurance Time (ET) before and after the training period. Compared to the control group, a significant increase in ΔHHb (P < 0.01) accompanied with an increase in ET (P < 0.01) and MViC (P < 0.01) of the quadriceps was obtained in the training group. However, no significant differences of MViC, ET and ΔHHb were observed in the control group. Multimodal aerobic and strength exercise programs enhance muscle oxygen utilization, which may partly explain the improvement in muscular strength and endurance, and the reduction of muscle fatigue in patients with breast cancer during an adjuvant chemotherapy period.

Exercise Training Lowers Arterial Blood Pressure Independently of Pannexin 1 in Men with Essential Hypertension.

Regular exercise training reduces arterial blood pressure, but the underlying mechanisms are unclear. Here, we evaluated the potential involvement of pannexin 1, an ATP releasing channel, in the blood pressure-reducing effect of training. Middle-age men, 13 normotensive and 14 nonmedicated stage 1 hypertensive, completed 8 wk of intensive aerobic cycle training. Before and after training, blood pressure and changes in leg vascular conductance, induced by femoral arterial infusion of tyramine (induces endogenous noradrenaline release), acetylcholine, or sodium nitroprusside, were measured during control conditions and after acute pannexin 1 inhibition by probenecid. A skeletal muscle biopsy was obtained from the thigh, pre- and posttraining. Exercise training reduced mean systolic and diastolic blood pressure by ~5 ( P = 0.013) and 5 mm Hg ( P < 0.001), respectively, in the hypertensive group only. The reduction in blood pressure was not related to changes in pannexin 1 function because mean arterial blood pressure and tyramine-induced vasoconstriction remain unaltered by pannexin 1 inhibition after training in both groups. After training, pannexin 1 inhibition enhanced leg vascular conductance in the normo- and hypertensive groups at baseline (41.5%, P = 0.0036, and 37.7%, P = 0.024, respectively) and in response to sodium nitroprusside infusion (275%, P = 0.038, and 188%, P = 0.038, respectively). Training did not alter the pannexin 1 protein expression in skeletal muscle. Training enhanced the vasodilator response to acetylcholine infusion and increased the expression of microvascular function-relevant proteins. The exercise training-induced lowering of arterial blood pressure in nonmedicated hypertensive men does not involve an altered function of pannexin 1.

The Preliminary Effects of Aerobic Cycling Training on Cognitive Function in People with Traumatic Brain Injury and Significant Memory Impairment: a Proof-Of-Concept Randomized Controlled Trial

<h3>Research Objectives</h3> To investigate effects of aerobic exercise training in persons with TBI-related memory impairment. <h3>Design</h3> Single-blinded randomized controlled trial. <h3>Setting</h3> Kessler Foundation. <h3>Participants</h3> Five participants completed the trial. All were right handed, suffered a severe TBI at least 10 years ago, were physically inactive, and were prescreened for significant memory impairment. <h3>Interventions</h3> Participants were randomly assigned to either 12-weeks of supervised moderate intensity (60% peak watts) aerobic cycling exercise training or 12-weeks of supervised stretching-and-toning as an active control condition. Both conditions took place 3x/week for 30 mins/session. <h3>Main Outcome Measures</h3> Pre- and post-intervention measures included a battery of neuropsychological assessments of memory and processing speed and structural neuroimaging (MRI), administered by treatment-blinded assessors. <h3>Results</h3> Based on effect size estimates, the exercise group demonstrated substantially greater improvements in auditory verbal learning (RAVLT) (d=1.54), and larger increases in volumes of the left hippocampus (d=1.49), left cerebellar cortex (d=0.95), and right cerebellar cortex (d=1.40). There were large intervention effects favoring the exercise condition on processing speed (SDMT) (d=1.58) and volume of the right thalamus (d=1.44). <h3>Conclusions</h3> Pilot data provide important proof-of-concept suggesting that a 12-week, moderate intensity, aerobic cycling exercise training program may specifically improve memory and more generally improve processing speed in those with TBI and impaired memory. <h3>Author(s) Disclosures</h3> The authors have no conflicts of interest to disclose.

Efficacy of simultaneous aerobic exercise and cognitive training in subjective cognitive decline: study protocol for randomized controlled trial of the Exergames Study

BackgroundSubjective cognitive decline (SCD) is an early manifestation of Alzheimer’s disease (AD) and offers a therapeutic window where interventions have strong potential to prevent or delay the progression of AD. Aerobic exercise and cognitive training represent two promising interventions for AD prevention, but their synergistic effect has yet to be assessed in persons with SCD.Methods/designThe purpose of this single-blinded, 3-parallel group randomized controlled trial is to test the synergistic efficacy of an exergame intervention (simultaneous moderate-intensity aerobic cycling and cognitive training) on cognition and aerobic fitness in community-dwelling older adults with SCD. The Exergames Study will randomize 96 participants on a 2:1:1 allocation ratio to 3-month exergame, cycling only, or attention control (stretching). Primary outcomes include global cognition and aerobic fitness, which will be assessed at baseline and after 3 months. The specific aims of the Exergames Study are to (1) determine the efficacy of the exergame in older adults with SCD and (2) assess the distraction effect of exergame on aerobic fitness. Data will be analyzed using ANOVA following intention-to-treat.DiscussionThis study will test the synergistic effects of exergame on cognition and aerobic fitness. It has the potential to advance prevention research for AD by providing effect-size estimates for future trials.Trial registrationClinicalTrials.gov NCT04311736. Registered on 17 March 2020.

Long-term intradialytic hybrid exercise training on fatigue symptoms in patients receiving hemodialysis therapy

Hemodialysis (HD) patients suffer from generalized weakness, exercise intolerance and muscle atrophy, all leading to generalized fatigue and lack of energy. HD patients spend at least 50% of their time in a functionally "switch off" mode with their fatigue sensations reaching a peak in the immediate hours after the dialysis session. The purpose of the current study was to assess the effectiveness of a nine-month hybrid intradialytic exercise program on fatigue symptoms occurring during and after hemodialysis session. Twenty stable hemodialysis patients were included in the study (59 ± 13.7 years; 16 males). All patients completed a 9-month supervised exercise training program composed of both aerobic cycling and resistance training during HD. Aspects related to physical and generalized fatigue were assessed via validated questionnaires, while physical performance was assessed by a battery of tests, before and after the intervention period. Exercise capacity and physical performance were increased by an average of 65 and 40%, respectively. Patients reported feeling better during post-dialysis hours in question 1 (p = 0.000), question 3 (p = 0.009) and question 4 (p = 0.003) after the 9-month intervention. In addition, exercise training improved scores in cognitive function (p = 0.037), vitality (p = 0.05), depression (p = 0.000) and fatigue (p = 0.039). The present study showed that a 9-month hybrid (aerobic + resistance) exercise training program improved symptoms of post-dialysis fatigue and overall general perception of fatigue. Hybrid exercise training is a safe and effective non-pharmacological approach to ameliorate fatigue symptoms in HD patients. Trial registration number The study is registered at ClinicalTrials.gov (NCT01721551, 2012) as a clinical trial.

Effects of aerobic cycling training on mobility and functionality of acute stroke subjects: A randomized clinical trial.

Studies demonstrate the benefits of aerobic cycling training in subacute and chronic stroke subjects, but there is a lack in the literature about its effects on the acute phase. Verify the effects of aerobic cycling training on lower limbs muscle strength, gait speed, balance, mobility and functionality of acute stroke subjects. Control group (CG) performed conventional physiotherapy twice a day and the intervention group (IG) performed a conventional physiotherapy and a cycle ergometer session, for five consecutive days. Subjects were assessed for muscle strength by a digital dynamometer, gait speed by the 10-meter-walk-test, balance by the Berg Balance Scale, mobility by the ICU-Mobility-Scale and functionality by the Perme Score. Twenty subjects were enrolled in the study, 10 in the CG and 10 in the IG. Lower limbs muscle strength, the main endpoint, was better in the IG compared to the CG. The same was found in the secondary endpoints. The intragroup analysis was also positive for the CG in the mobility and functionality. Conventional physiotherapy combined with cycling exercise showed better results in the improvement of muscle strength of lower limbs, mobility and functionality of subjects who suffered from acute stroke.

Combined training of aerobic exercise and 3D video game to improve hippocampal and memory functions in older adults: An RCT trial

AbstractBackgroundWith the proportion of older adults rising, the progressive cognitive decline and dementia have become one of the most serious public health issues worldwide. As a result, there is a pressing need for developing effective non‐pharmaceutical intervention programs to counteract age‐related cognitive decline. Animal models robustly support that aerobic exercise can effectively improve neurogenesis and memory, whereas most of the current findings from human studies are in contrast. We speculated that two reasons may contribute to these inconsistent findings in human research. One is that hippocampal neurogenesis induced by the aerobic exercise is more likely to survive when simultaneously accompanied by cognitive stimulations, particularly when the cognitive goals are challenging. Another is that the beneficial effects from aerobic exercise are specific to hippocampal dependent memory tasks. Therefore, we designed a training program by combining aerobic cycling with 3D video game.MethodWe conducted a randomized controlled trial with healthy older adults randomly assigned to combined aerobic cycling and 3D video game training group (n=22), aerobic cycling group (n=23), 3D video games group (n=25), or control group (n=28). The effects of combined training on neuroplasticity (including plasma brain‐derived neurotrophic growth factor, hippocampal gray matter volume, and hippocampal‐cortical functional connectivity) and cognitive plasticity (focusing on hippocampal‐dependent memory, tested via Mnemonic Similarity Task) were examined compared with all three other groups. The training lasted four months with a frequency of twice per week, 1hour per session.ResultThe combined and video game training groups reported equivalent game experiences and reached similar game levels. The average and maximum heart rates were being monitored to ensure a medium exercise intensity in both combined and cycling groups. In addition self‐reported fatigue levels were equivalent in these two groups. The preliminary behavioral data analysis revealed that combined group performed better on immediate and delayed memory recall. More importantly, there was a larger effect size in pattern separation task in combined group (Cohen’s d =1.12) than in cycling (Cohen’s d =0.49) and video game (Cohen’s d =0.55) groups.ConclusionCombined aerobic exercise ‐ video game training could improve hippocampal‐dependent memory functions, which waits the MRI data analysis to further prove.

Microvascular Function Is Impaired after Short-Term Immobilization in Healthy Men.

We examined whether 2 wk of one-leg immobilization would impair leg microvascular function and to what extent a subsequent period of intense aerobic cycle training could restore function. Study participants were healthy young men (n = 12; 20-24 yr of age). Leg microvascular function was determined before the intervention, after the immobilization period, and after a 4-wk exercise training period. Microvascular function was assessed as the vasodilator response to intra-arterial infusion of acetylcholine and sodium nitroprusside and as the vasoconstrictor response to endogenous noradrenaline release induced by tyramine infusion. Vasodilator enzymes as well as prooxidant and antioxidant enzymes were assessed by protein analysis in skeletal muscle samples: endothelial nitric oxide synthase, NADPH oxidase (NOX p67 and NOX gp91), and superoxide dismutase 2 (SOD2). The acetylcholine-induced change in vascular conductance was reduced after the 2 wk of immobilization (P = 0.003), tended to increase (P = 0.061), and was back to baseline levels after the subsequent 4 wk of exercise training. Plasma prostacyclin levels in response to acetylcholine infusion were lower after immobilization than before (P = 0.041). The changes in vascular conductance with sodium nitroprusside and tyramine were similar during all conditions. Skeletal muscle protein levels of endothelial nitric oxide synthase in the experimental leg were unchanged with immobilization and subsequent training but increased 47% in the control leg with training (P = 0.002). NOX p67, NOX gp91, and SOD2 in the experimental leg remained unaltered with immobilization, and SOD2 was higher than preimmobilization after 4 wk of training (P < 0.001). The study shows that 2 wk of immobilization impairs leg microvascular endothelial function and prostacyclin formation but that 4 wk of intense aerobic exercise training restores the function. The underlying mechanism may reside in the prostacyclin system.

Angiogenic potential is reduced in skeletal muscle of aged women.

The risk of cardiovascular disease and associated skeletal muscle microvascular rarefaction is enhanced in women after menopause, yet knowledge about the angiogenic potential in ageing women is generally sparse. Aged healthy and sedentary women were found to present a markedly impaired capacity for proliferation of skeletal muscle derived microvascular endothelial cells compared to young women. Vascular endothelial growth factor (VEGF) levels in skeletal muscle myocytes and release of VEGF from myocytes tended to be lower in aged compared to young women. The aged women did not show a detectable increase in skeletal muscle capillarization with 8weeks of intense aerobic cycle training. Combined, the findings indicate that aged women have a reduced potential for capillary growth in skeletal muscle which, with ageing, may lead to age-induced microvascular rarefaction. Skeletal muscle angiogenic potential was examined in cell cultures derived from aged and young women, and the effect of 8weeks of intense cycle training on muscle capillary growth was determined in the group of aged women. Basal muscle samples were obtained from healthy sedentary aged (n=12; 64±4.2years) and young women (n=5; 24±3.2years) for endothelial cell and skeletal muscle myocyte isolation and experiments. In addition, the aged women completed an 8-week training intervention. Peak oxygen uptake and muscle samples for histology and protein determination were obtained before and after the training period. Before training, muscle microdialysate was collected from the aged women at rest and during exercise. In Part 1 of the experiments, growth-supplement stimulated proliferation of endothelial cells was ∼75% lower in cells from aged compared to young women (P<0.001). There was a tendency for a lower vascular endothelial growth factor (VEGF) concentration in muscle conditioned media (P=0.0696) and for a lower VEGF content in the myocytes (P=0.0705) from aged compared to young women. Endothelial proliferation was found to be highly dependent on mitochondrial function. Acute exercise resulted in a modest (1.3-fold; P=0.0073) increase in muscle interstitial VEGF protein in the aged women. In Part 2, 8weeks of intense training did not change muscle capillarization (P≥0.1502) in the aged women, but led to an increased amount of muscle VEGF (P=0.0339). In conclusion, aged women have impaired angiogenic potential, which is associated with a compromised response both at the skeletal muscle myocyte and microvascular endothelial cell level.

Regulation of Proteins in Human Skeletal Muscle: The Role of Transcription

Regular low intensity aerobic exercise (aerobic training) provides effective protection against various metabolic disorders. Here, the roles played by transient transcriptome responses to acute exercise and by changes in baseline gene expression during up-regulation of protein content in human skeletal muscle were investigated after 2 months of aerobic training. Seven untrained males were involved in a 2 month aerobic cycling training program. Mass-spectrometry and RNA sequencing were used to evaluate proteome and transcriptome responses to training and acute exercise. We found that proteins with different functions are regulated differently at the transcriptional level; for example, a training-induced increase in the content of extracellular matrix-related proteins is regulated at the transcriptional level, while an increase in the content of mitochondrial proteins is not. An increase in the skeletal muscle content of several proteins (including mitochondrial proteins) was associated with increased protein stability, which is related to a chaperone-dependent mechanism and/or reduced regulation by proteolysis. These findings increase our understanding of the molecular mechanisms underlying regulation of protein expression in human skeletal muscle subjected to repeated stress (long term aerobic training) and may provide an opportunity to control the expression of specific proteins (e.g., extracellular matrix-related proteins, mitochondrial proteins) through physiological and/or pharmacological approaches.

L’activité physique, un facteur protecteur cardiovasculaire et métabolique chez les patients porteurs d’une insuffisance rénale terminale

ObjectiveThe aim of the study was to test the effectiveness of Physical Activity (PA) during haemodialysis as a protective treatment against cardiovascular (CV) diseases. MethodsEighty volunteer patients were included in this multicentric prospective study and followed for two years: 40 patients in the Exercise group (EX), 40 patients in the Control group (Ctrl). CV risk factors: Total Cholesterol, HDL Cholesterol (HDL-c), LDL cholesterol (LDL-c), Triglycerides (TG) and Hemoglobin (Hb), and Prealbumin, Albumin, Parathormon, 25-OH Vitamin D, were checked at Month 0 (M0) and Month 24 (M24). The number of antihypertensive treatments and the Erythropoietin Stimulating Agent (ESA) required doses were collected. We noted for each group during the follow-up the number of hospitalizations for CV reasons. After two years, we compared 31 patients in EX and 35 in Ctrl. ResultsWe observed a significant decrease of total cholesterol EX group: 1.86±0.49g/L at M0 versus 1.64±0.38g/L at M24 (P<0.05). HDLc and but LDL-c remained stable in both groups. TG decreased significantly in EX: 1.76±0.89g/L vs 1.44±0.69g/L (P<0.05). The number of antihypertensive drugs per patient decreased significantly (P<0.05) in the EX group between M0 and M24 (1.61±1.28 at M0 and 0.74±0.85 at M24). The EX patients were three times less frequently hospitalized for cardiovascular reasons. There were five hospital stays versus 14 for the Ctrl group. ConclusionOur study demonstrates that an intradialytic aerobic cycling training program promotes beneficial effects on cardiovascular protection. Physical activity reduced the number of CV events in our population during two years follow-up.

Aerobic Exercise Training Increases Muscle Water Content in Obese Middle-Age Men.

The objective of this study is to determine whether muscle water content (H2Omuscle) expands with training in deconditioned middle-age men and the effects of this expansion in other muscle metabolites. Eighteen obese (BMI = 33 ± 3 kg⁻¹·m⁻²) untrained (V˙O2peak = 29 ± 7 mL⁻¹·kg⁻¹·min⁻¹) metabolic syndrome men completed a 4-month aerobic cycling training program. Vastus lateralis muscle biopsies were collected before and 72 h after the completion of the last training bout. Water content, total protein, glycogen concentration, and citrate synthase activity were measured in biopsy tissue. Body composition was assessed using dual-energy X-ray absorptiometry, and cardiometabolic fitness was measured during an incremental cycling test. Body weight and fat mass were reduced -1.9% and -5.4%, respectively (P < 0.05), whereas leg fat free mass increased with training (1.8%, P = 0.023). Cardiorespiratory fitness (i.e., V˙O2peak), exercise maximal fat oxidation (i.e., FOmax), and maximal cycling power (i.e., Wmax) improved with training (11%, 33%, and 10%, respectively; P < 0.05). After 4 months of training, H2Omuscle increased from 783 ± 18 to 799 ± 24 g·kg⁻¹ wet weight (ww) (2%, P = 0.011), whereas muscle protein concentration decreased 11% (145 ± 15 to 129 ± 13 g·kg⁻¹ ww, P = 0.007). Citrate synthase activity (proxy for mitochondrial density) increased by 31% (17 ± 5 to 22 ± 5 mmol·min⁻¹·kg⁻¹ ww, P = 0.024). Muscle glycogen concentration increased by 14% (22 ± 7 to 25 ± 7 g·kg⁻¹ ww) although without reaching statistical significance when expressed as per kilogram of wet weight (P = 0.15). Our findings suggest that aerobic cycling training increases quadriceps muscle water although reduces muscle protein concentration in obese metabolic syndrome men. Reduced protein concentration coexists with increased leg lean mass suggestive of a water dilution effect that however does not impair increased cycling leg power with training.

Combined omega-3 fatty acids, aerobic exercise and cognitive stimulation prevents decline in gray matter volume of the frontal, parietal and cingulate cortex in patients with mild cognitive impairment

Previous studies in older adults suggested beneficial effects of omega-3 fatty acid (FA) supplementation, aerobic exercise, or cognitive stimulation on brain structure and function. However, combined effects of these interventions in patients suffering from mild cognitive impairment (MCI) are unknown. Using a randomized interventional design, we evaluated the effect of combined omega-3 FA supplementation, aerobic exercise and cognitive stimulation (target intervention) versus omega-3 FA supplementation and non-aerobic exercise (control intervention) on cognitive function and gray matter volume in patients with MCI. Moreover, we analyzed potential vascular, metabolic or inflammatory mechanisms underlying these effects. Twenty-two MCI patients (8 females; 60–80years) successfully completed six months of omega-3 FA intake, aerobic cycling training and cognitive stimulation (n=13) or omega-3 FA intake and non-aerobic stretching and toning (n=9). Before and after the interventions, cognitive performance, magnetic resonance imaging of the brain at 3T (n=20), intima-media thickness of the internal carotid artery and serum markers of glucose control, lipid and B-vitamin metabolism, and inflammation were assessed. Intervention-related changes in gray matter volume of Alzheimer's disease (AD)-related brain regions, i.e., frontal, parietal, temporal and cingulate cortex were examined using voxel-based morphometry of high resolution T1-weighted images.After the intervention period, significant differences emerged in brain structure between groups: Gray matter volume decreased in the frontal, parietal and cingulate cortex of patients in the control intervention, while gray matter volume in these areas was preserved or even increased after the target intervention. Decreases in homocysteine levels in the target intervention group were associated with increases in gray matter volume in the middle frontal cortex (p=0.010). No significant differences in cognitive performance or other vascular, metabolic and inflammatory parameters were observed between groups. This pilot study provides preliminary evidence that omega-3 FA intake combined with aerobic exercise and cognitive stimulation prevents atrophy in AD-related brain regions in MCI patients, compared to omega-3 FA intake plus the control condition of stretching and toning. These promising findings should now be validated in a larger interventional trial.

Skeletal muscle mitochondrial H2 O2 emission increases with immobilization and decreases after aerobic training in young and older men.

Currently, it is not known whether impaired mitochondrial function contributes to human ageing or whether potential impairments in mitochondrial function with age are secondary to physical inactivity. The present study investigated mitochondrial respiratory function and reactive oxygen species emission at a predefined membrane potential in young and older men subjected to 2 weeks of one-leg immobilization followed by 6 weeks of aerobic cycle training. Immobilization increased reactive oxygen species emission and decreased ATP generating respiration. Subsequent aerobic training reversed these effects. By contrast, age had no effect on the measured variables. The results of the present study support the notion that increased mitochondrial reactive oxygen species production mediates the detrimental effects seen after physical inactivity and that ageing per se does not cause mitochondrial dysfunction. Mitochondrial dysfunction, defined as increased oxidative stress and lower capacity for energy production, may be seen with ageing and may cause frailty, or it could be that it is secondary to physical inactivity. We studied the effect of 2 weeks of one-leg immobilization followed by 6 weeks of supervised cycle training on mitochondrial function in 17 young (mean ± SEM: 23 ± 1 years) and 15 older (68 ± 1 years) healthy men. Submaximal H2 O2 emission and respiration were measured simultaneously at a predefined membrane potential in isolated mitochondria from skeletal muscle using two protocols: pyruvate + malate (PM) and succinate + rotenone (SR). This allowed measurement of leak and ATP generating respiration from which the coupling efficiency can be calculated. The protein content of the anti-oxidants manganese superoxide dismuthase (MnSOD), CuZn superoxide dismuthase, catalase and gluthathione peroxidase 1 was measured by western blotting. Immobilization decreased ATP generating respiration using PM and increased H2 O2 emission using both PM and SR similarly in young and older men. Both were restored to baseline after the training period. Furthermore, MnSOD and catalase content increased with endurance training. The young men had a higher leak respiration at inclusion using PM and a higher membrane potential in State 3 using both substrate combinations. Collectively, the findings of the present study support the notion that increased mitochondrial reactive oxygen species mediates the detrimental effects seen after physical inactivity. Age, on the other hand, was not associated with impairments in anti-oxidant protein levels, mitochondrial respiration or H2 O2 emission using either protocol.