Months Of Aerobic Training Research Articles

Sex-Specific Skeletal Muscle Gene Expression Responses to Exercise Reveal Novel Direct Mediators of Insulin Sensitivity Change.

Understanding the causal pathways, systems, and mechanisms through which exercise impacts human health is complex. This study explores molecular signaling related to whole-body insulin sensitivity (Si) by examining changes in skeletal muscle gene expression. The analysis considers differences by biological sex, exercise amount, and exercise intensity to identify potential molecular targets for developing pharmacologic agents that replicate the health benefits of exercise. The study involved 53 participants from the STRRIDE I and II trials who completed eight months of aerobic training. Skeletal muscle gene expression was measured using Affymetrix and Illumina technologies, while pre- and post-training Si was assessed via an intravenous glucose tolerance test. A novel gene discovery protocol, integrating three literature-derived and data-driven modeling strategies, was employed to identify causal pathways and direct causal factors based on differentially expressed transcripts associated with exercise intensity and amount. In women, the transcription factor targets identified were primarily influenced by exercise amount and were generally inhibitory. In contrast, in men, these targets were driven by exercise intensity and were generally activating. Transcription factors such as ATF1, CEBPA, BACH2, and STAT1 were commonly activating in both sexes. Specific transcriptional targets related to exercise-induced Si improvements included TACR3 and TMC7 for intensity-driven effects, and GRIN3B and EIF3B for amount-driven effects. Two key signaling pathways mediating aerobic exercise-induced Si improvements were identified: one centered on estrogen signaling and the other on phorbol ester (PKC) signaling, both converging on the epidermal growth factor receptor (EGFR) and other relevant targets. The signaling pathways mediating Si improvements from aerobic exercise differed by sex and were further distinguished by exercise intensity and amount. Transcriptional adaptations in skeletal muscle related to Si improvements appear to be causally linked to estrogen and PKC signaling, with EGFR and other identified targets emerging as potential skeletal muscle-specific drug targets to mimic the beneficial effects of exercise on Si.

Long-term detraining reverses the improvement of lifelong exercise on skeletal muscle ferroptosis and inflammation in aging rats: fiber-type dependence of the Keap1/Nrf2 pathway.

We investigated the effects of lifelong aerobic exercise and 8months of detraining after 10months of aerobic training on circulation, skeletal muscle oxidative stress, and inflammation in aging rats. Sprague-Dawley rats were randomly assigned to the control (CON), detraining (DET), and lifelong aerobic training (LAT) groups. The DET and LAT groups began aerobic treadmill exercise at the age of 8months and stopped training at the 18th and 26th month, respectively; all rats were sacrificed when aged 26months. Compared with CON, LAT remarkably decreased serum and aged skeletal muscle 4-hydroxynonenal (4-HNE) and 8-hydroxy-2-deoxyguanosine (8-OHdG) levels. Superoxide dismutase 2(SOD2) levels were higher in the LAT group than in the CON group in skeletal muscle. However, DET remarkably decreased SOD2 protein expression and content in the skeletal muscle and increased malondialdehyde (MDA) level compared with LAT. Compared with LAT, DET remarkably downregulated adiponectin and upregulated tumor necrosis factor alpha (TNF-α) expression, while phosphoinositide 3-kinase (PI3K), protein kinase B (AKT), and 70-kDa ribosomal protein S6 kinase (P70S6K) protein expression decreased, and that of FoxO1 and muscle atrophy F-box (MAFbX) proteins increased in the quadriceps femoris. Adiponectin and TNF-α expression in the soleus muscle did not change between groups, whereas that of AKT, mammalian target of rapamycin (mTOR), and P70S6K was lower in the soleus in the DET group than in that in the LAT group. Compared with that in the LAT group, sestrin1 (SES1) and nuclear factor erythroid 2-related factor 2 (Nrf2) protein expression in the DET group was lower, whereas Keap1 mRNA expression was remarkably upregulated in the quadriceps femoris. Interestingly, the protein and mRNA levels of SES1, Nrf2, and Keap1 in soleus muscle did not differ between groups. LAT remarkably upregulated ferritin heavy polypeptide 1(FTH), glutathione peroxidase 4(GPX4), and solute carrier family 7member 11 (SLC7A11) protein expression in the quadriceps femoris and soleus muscles, compared with CON. However, compared with LAT, DET downregulated FTH, GPX4, and SLC7A11 protein expression in the quadriceps femoris and soleus muscles. Long-term detraining during the aging phase reverses the improvement effect of lifelong exercise on oxidative stress, inflammation, ferroptosis, and muscle atrophy in aging skeletal muscle. The quadriceps femoris is more evident than the soleus, which may be related to the different changes in the Keap1/Nrf2 pathway in different skeletal muscles.

Six months of aerobic exercise training does not prevent a worsening of glucose tolerance in individuals with acute spinal cord injury

Individuals with spinal cord injuries (SCI) have a greater incidence of Type 2 Diabetes (T2D) than their non-injured peers. The increased incidence of T2D has been noted in individuals within the first few years after injury, and incidence increases with time since injury. Aerobic exercise training improves long-term glycemic control in non-injured individuals and results in improved glycemic control in individuals with chronic SCI (>10 years). However, it is unknown whether individuals with acute injuries (<3 years) display altered glucose control, and if aerobic training may prevent worsening of glucose control and T2D. Therefore, we assessed blood glucose regulation in individuals <3 years post SCI injury. Glucose regulation was assessed through fasting blood glucose, insulin, hemoglobin A1C (HbA1C), homeostatic model assessment for insulin resistance (HOMA-IR), and an oral glucose tolerance test (OGTT). In addition, body composition was estimated via dual energy x-ray absorptiometry. These assessments were made prior to, and following 3- and 6-months (mo) of aerobic exercise training consisting of hybrid functional electrical stimulation rowing. Data were analyzed with 1-way RMANOVA. Eight individuals (1F, 7M, age 20-45 years) with SCI 9-27 mo post-injury and a neurological level of injury from spinal cord segments C3 to T3 were enrolled. Individuals exercised for 30min per session, at ~60% VO2peak, 2-3 times per week. Fasting glucose (Pre:85±9, 3m:88±8, 6m:86±2 mg/dL, p=0.55), insulin (Pre:6.0±3.8, 3m:5.7±2.5, 6m:3.9±2.5 uIU/mL, p=0.25), HbA1C (Pre:4.9±0.3, 3m:5.0±0.3, 6m:4.8±0.1%, p=0.73) and HOMA-IR (Pre:1.4±1.0, 3m:1.2±0.7, 6m:0.7±0.4, p=0.26) did not change after 6-mo of training. In contrast, the dynamic assessment of glucose tolerance (OGTT) showed dramatic worsening (AUC Pre:15.7±3.8, 3m:17.8±5.9, 6m:17.6±5.8 units, p=0.04) from pre-exercise to 3-mo. Moreover, following 6-mo of exercise training, 1 individual met the diagnostic criteria for impaired glucose tolerance and another 2 for diabetes. Exercise training did not change visceral adipose mass (Pre:1.4±0.9, 3m:1.4±1.2, 6m:1.3±1.2 kg, p=0.96) or total body lean mass (Pre:50.4±9.5, 3m:49.6±9.6, 6m:49.5±9.5kg, p=0.98). These results suggest that fasting measures alone are not sensitive enough in detecting impairments in glucose metabolism in the acute period following a SCI. Interestingly, in people with SCI, whole-body aerobic exercise does not prevent the occurrence of impaired glucose metabolism. The worsening of glucose tolerance occurs despite a conservation of lean mass and no increase in visceral adiposity. It will be of importance to determine the mechanisms underlying the worsening of glycemic control and develop therapies to prevent metabolic disease in SCI. R01 HL117037, F32 HL156675 This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Aerobic exercise improves executive functions in females, but not males, without the BDNF Val66Met polymorphism

BackgroundAerobic exercise promotes cognitive function in older adults; however, variability exists in the degree of benefit. The brain-derived neurotropic factor (BDNF) Val66Met polymorphism and biological sex are biological factors that have been proposed as important modifiers of exercise efficacy. Therefore, we assessed whether the effect of aerobic exercise on executive functions was dependent on the BDNFval66met genotype and biological sex.MethodsWe used data from a single-blind randomized controlled trial in older adults with subcortical ischemic vascular cognitive impairment (NCT01027858). Fifty-eight older adults were randomly assigned to either the 6 months, three times per week progressive aerobic training (AT) group or the usual care plus education control (CON) group. The secondary aim of the parent study included executive functions which were assessed with the Trail Making Test (B–A) and the Digit Symbol Substitution Test at baseline and trial completion at 6 months.ResultsAnalysis of covariance, controlling for baseline global cognition and baseline executive functions performance (Trail Making Test or Digit Symbol Substitution Test), tested the three-way interaction between experimental group (AT, CON), BDNFval66met genotype (Val/Val carrier, Met carrier), and biological sex (female, male). Significant three-way interactions were found for the Trail Making Test (F(1,48) = 4.412, p < 0.04) and Digit Symbol Substitution Test (F(1,47) = 10.833, p < 0.002). Posthoc analyses showed female Val/Val carriers benefited the most from 6 months of AT compared with CON for Trail Making Test and Digit Symbol Substitution Test performance. Compared with CON, AT did not improve Trail Making Test performance in male Val/Val carriers or Digit Symbol Substitution Test performance in female Met carriers.ConclusionsThese results suggest that future randomized controlled trials should take into consideration BDNF genotype and biological sex to better understand the beneficial effects of AT on cognitive function in vascular cognitive impairment to maximize the beneficial effects of exercise and help establish exercise as medicine for cognitive health.

Aerobic exercise training resets the human skeletal muscle methylome 10 years after breast cancer treatment and survival.

Cancer survivors suffer impairments in skeletal muscle in terms of reduced mass and function. Interestingly, human skeletal muscle possesses an epigenetic memory of earlier stimuli, such as exercise. Long-term retention of epigenetic changes in skeletal muscle following cancer survival and/or exercise training has not yet been studied. We, therefore, investigated genome-wide DNA methylation (methylome) in skeletal muscle following a 5-month, 3/week aerobic-training intervention in breast cancer survivors 10-14 years after diagnosis and treatment. These results were compared to breast cancer survivors who remained untrained and to age-matched controls with no history of cancer, who undertook the same training intervention. Skeletal muscle biopsies were obtained from 23 females before(pre) and after(post) the 5-month training period. InfiniumEPIC 850K DNA methylation arrays and RT-PCR for gene expression were performed. The breast cancer survivors displayed a significant retention of increased DNA methylation (i.e., hypermethylation) at a larger number of differentially methylated positions (DMPs) compared with healthy age-matched controls pre training. Training in cancer survivors led to an exaggerated number of DMPs with a hypermethylated signature occurring at non-regulatory regions compared with training in healthy age-matched controls. However, the opposite occurred in important gene regulatory regions, where training in cancer survivors elicited a considerable reduction in methylation (i.e., hypomethylation) in 99% of the DMPs located in CpG islands within promoter regions. Importantly, training was able to reverse the hypermethylation identified in cancer survivors back toward a hypomethylated signature that was observed pre training in healthy age-matched controls at 300 (out of 881) of these island/promoter-associated CpGs. Pathway enrichment analysis identified training in cancer survivors evoked a predominantly hypomethylated signature in pathways associated with cell cycle, DNA replication/repair, transcription, translation, mTOR signaling, and the proteosome. Differentially methylated region (DMR) analysis also identified genes: BAG1, BTG2, CHP1, KIFC1, MKL2, MTR, PEX11B, POLD2, S100A6, SNORD104, and SPG7 as hypermethylated in breast cancer survivors, with training reversing these CpG island/promoter-associated DMRs toward a hypomethylated signature. Training also elicited a largely different epigenetic response in healthy individuals than that observed in cancer survivors, with very few overlapping changes. Only one gene, SIRT2, was identified as having altered methylation in cancer survivors at baseline and after training in both the cancer survivors and healthy controls. Overall, human skeletal muscle may retain a hypermethylated signature as long as 10-14 years after breast cancer treatment/survival. Five months of aerobic training reset the skeletal muscle methylome toward signatures identified in healthy age-matched individuals in gene regulatory regions.

Carotid Arterial Compliance and Aerobic Exercise Training in Chronic Traumatic Brain Injury: A Pilot Study.

Decreased carotid arterial compliance (CAC) is associated with cerebral microvascular damage, cerebral blood flow (CBF) dysregulation, and increased risk for stroke and dementia, which are reported to be prevalent after traumatic brain injury (TBI). However, the effect of TBI on CAC has not been reported. The purposes of this pilot study were to (1) compare CAC between participants with chronic traumatic brain injury (cTBI) and age-matched healthy control (HC) subjects and (2) to examine whether CAC changed after 3 months of exercise training in those with cTBI. Community based. Nineteen participants with cTBI (6-72 months postinjury) and 19 HC matched for age and sex were tested at baseline. The same cTBI cohort was enrolled in a proof-of-concept randomized controlled exercise training program to investigate the effects of 3 months of aerobic exercise training (AET) or nonaerobic stretching and toning (SAT) on cerebrovascular parameters. Cross-sectional study and randomized controlled trial. CAC was measured by tonometry and ultrasonography at the common carotid artery; CBF was measured by ultrasonography at the bilateral internal carotid and vertebral arteries, and pulsatile CBF was measured by transcranial Doppler ultrasonography at the middle cerebral arteries. Cerebrovascular resistance (CVR) was calculated as mean arterial pressure divided by total CBF. Relative to HC, the participants with cTBI had lower CAC (0.10 ± 0.03 vs 0.12 ± 0.03 mm 2 /mm Hg, P = .046) and higher CVR (0.17 ± 0.03 vs 0.15 ± 0.03 mm Hg/mL/min, P = .028). CAC tended to increase after AET compared with SAT ( P = .080). Increases in CAC were associated with decreased pulsatile CBF ( r = -0.689, P = .003). These findings suggest that the individuals with cTBI have decreased CAC, which may potentially be improved by AET.

The Effect of Aerobic Training and Increasing Nonexercise Physical Activity on Cardiometabolic Risk Factors.

Epidemiological studies suggest that sedentary behavior is an independent risk factor for cardiovascular mortality independent of meeting physical activity guidelines. However, limited evidence of this relationship is available from prospective interventions. The purpose of the present study is to evaluate the combined effect of aerobic training and increasing nonexercise physical activity on body composition and cardiometabolic risk factors. Obese adults (N = 45) were randomized to 6 months of aerobic training (AERO), aerobic training and increasing nonexercise physical activity (~3000 steps above baseline levels; AERO-PA), or a control (CON) group. The AERO and AERO-PA groups performed supervised aerobic training (3-4 times per week). The AERO-PA group wore Fitbit One accelerometers and received behavioral coaching to increase nonexercise physical activity. There was a larger increase in fitness in the AERO-PA group (0.27 L·min-1; confidence interval (CI), 0.16 to 0.40 L·min-1) compared with the AERO group (0.09 L·min-1; CI, -0.04 to 0.22 L·min-1) and the CON group (0.01; CI, -0.11 to 0.12 L·min-1). Although significant findings were not observed in the entire study sample, when the analysis was restricted to participants compliant to the intervention (n = 33), we observed significant reductions in waist circumference, percent weight loss, body fat, 2-h glucose, and 2-h insulin in comparison to the CON group (P < 0.05), but not the AERO group. Furthermore, linear regression models showed that change in steps was associated with 21% and 26% of the variation in percent weight loss and percent fat loss, respectively. Increasing nonexercise physical activity with aerobic training may represent a viable strategy to augment the fitness response in comparison to aerobic training alone and has promise for other health indicators.

Aerobic Versus Resistance Training Effects on Ventricular-Arterial Coupling and Vascular Function in the STRRIDE-AT/RT Trial.

Background: The goal was studying the differential effects of aerobic training (AT) vs. resistance training (RT) on cardiac and peripheral arterial capacity on cardiopulmonary (CP) and peripheral vascular (PV) function in sedentary and obese adults.Methods: In a prospective randomized controlled trial, we studied the effects of 6 months of AT vs. RT in 21 subjects. Testing included cardiac and vascular ultrasoundography and serial CP for ventricular-arterial coupling (Ees/Ea), strain-based variables, brachial artery flow-mediated dilation (BAFMD), and peak VO2 (pVO2; mL/kg/min) and peak O2-pulse (O2p; mL/beat).Results: Within the AT group (n = 11), there were significant increases in rVO2 of 4.2 mL/kg/min (SD 0.93) (p = 0.001); O2p of 1.9 mL/beat (SD 1.3) (p = 0.008) and the brachial artery post-hyperemia peak diameter 0.18 mm (SD 0.08) (p = 0.05). Within the RT group (n = 10) there was a significant increase in left ventricular end diastolic volume 7.0 mL (SD 9.8; p = 0.05) and percent flow-mediated dilation (1.8%) (SD 0.47) (p = 0.004). Comparing the AT and RT groups, post exercise, rVO2 2.97, (SD 1.22), (p = 0.03), O2p 0.01 (SD 1.3), (p = 0.01), peak hyperemic blood flow volume (1.77 mL) (SD 140.69) (p = 0.009), were higher in AT, but LVEDP 115 mL (SD 7.0) (p = 0.05) and Ees/Ea 0.68 mmHg/ml (SD 0.60) p = 0.03 were higher in RT.Discussion: The differential effects of AT and RT in this hypothesis generating study have important implications for exercise modality and clinical endpoints.

Aerobic exercise affects sleep, psychological wellbeing and immune system parameters among subjects with chronic primary insomnia.

Chronic primary insomnia is characterized by long-term difficulties in maintaining and initiating sleep, too early waking up, poor mood, fatigue, impaired concentration and poor quality of life. Exercise training is recommended to prevent and alleviate sleep disorders. The aim of the study was to investigate the influence of aerobic exercise training on quality of sleep, psychological wellbeing and immune system among subjects with chronic primary insomnia. Eighty previously sedentary subjects with chronic primary insomnia subjects enrolled in this study, their age ranged from 35-56 years. All participants were randomly assigned to supervised aerobic exercise intervention group (group A, n=40) or control group (group B, n=40). Polysomnographic recordings for sleep quality assessment, Beck Depression Inventory (BDI), Profile of Mood States(POMS), Rosenberg Self-Esteem Scale (RSES), number of CD3+, CD4+, CD8+ T cells count and CD4/CD8 ratio were measured before and at the end of the study after six months. There was a significant increase in the total sleep duration, sleep efficiency and sleep onset latency in group(A) after six months of aerobic exercise training, while, wake time after sleep onset and rapid eye movement (REM) latency significantly reduced after six months of aerobic training compared with values obtained prior to aerobic exercise training. Also, the mean values of BDI, POMS, CD3 count, CD4 count and CD8 count decreased significantly and the mean value of RSES significantly increased in group (A) after the aerobic exercise training, while the results of the control group were not significant. Moreover, there were significant differences between both groups at the end of the study. Exercise training can be considered as a non-pharmacological modalty for modifying sleep quality, psychological wellbeing and immune system among subjects with chronic primary insomnia.

Resistance exercise improves cognitive and brain health in overweight older adults

AbstractBackgroundApproximately 50% of Canadian older adults over the age of 60 are overweight or obese (based on body mass index; BMI). Individuals with high BMI (≥25) often experience cognitive and brain deficits (e.g., impaired memory, cortical atrophy, reduced neural activation), and are at high risk of dementia. One promising lifestyle intervention that may improve these deficits is exercise. For example, 6 months of aerobic training has been found to improve cognitive and brain function in overweight older adults, however studies examining whether resistance training (RT) can produce comparable results in this population is limited.MethodWe conducted a 6‐month, thrice‐weekly randomized controlled trial of RT in overweight older adults. Twenty‐four participants aged 60‐80 (sedentary; BMI ≥25) were randomized into one of two groups: 1) progressive resistance (weight) training, or 2) balance and tone (BAT; control; stretching exercises). At pre‐ and post‐intervention (0 and 6 months, respectively), we measured associative memory performance during functional MRI, and obtained high resolution T1 weighted structural images from a 3T scanner.ResultSix months of RT showed significant improvements in memory performance (6.38% reduced error rate) compared to BAT. Similarly, structural imaging showed increased hippocampal volume for RT (+0.04%) as well as increased percent signal change (neural activation) in memory‐related brain regions of interest, including the hippocampus, parahippocampal gyrus, lingual gyrus, and medial temporal gyrus, suggesting improved functional brain health overtime.ConclusionOverall, our findings offer a feasible, cost‐efficient lifestyle intervention strategy to improve cognitive and brain health in overweight older adults.

Women and men with coronary heart disease respond similarly to different aerobic exercise training modalities: a pooled analysis of prospective randomized trials.

We aimed to compare cardiopulmonary exercise test (CPET) parameters, cardiac adaptations, and proportion of responders after different aerobic training programs amongst women and men with coronary heart disease (CHD). Patients with CHD were evaluated with a CPET and echocardiography before and after 3 months of aerobic exercise training. Peak oxygen uptake exercise training response was assessed according to the median peak oxygen uptake change for post- versus pretraining in the whole cohort (stratification non/low responders (NLR) vs. high-responders) and normalized for lean body mass (LBM). Eighty-three CHD patients were included (19 women, 64 men; 27 patients with interval, 19 with continuous, and 37 with combination exercises). Peak oxygen uptake, peak workload normalized for LBM, pulmonary variables (i.e., ventilation and oxygen uptake efficiency slope), and O2 pulse were significantly lower in women versus men. These parameters improved similarly with training in both sexes (p < 0.05). There were no differences in the proportion of NLR among women and men with CHD (7/19 (37%) vs. 35/64 (55%), p = 0.1719). Left ventricular ejection fraction and mean peak early diastolic mitral annulus velocity improved similarly with training in both sexes (p < 0.05). Women and men with CHD have a similar exercise training response regarding key CPET and echocardiographic parameters. The proportion of responders is similar. ClinicalTrials.gov: NCT03414996, NCT02048696, NCT03443193. Novelty: Cardiopulmonary adaptations to exercise training are similar among CHD men and women. Proportion of peak oxygen uptake for non/low/high responders is similar in CHD men and women. Left ventricular systolic and diastolic function improved similarly after exercise training in CHD men and women.

Three Months Of Aerobic Exercise Training Improves Vascular Endothelial Function In Overweight/obese Older Adults

Aging and overweight/obesity (OW/O) are associated with insulin resistance (IR) and impaired vascular endothelial function (VEF), potentially increasing cardiovascular disease (CVD) risk. Aerobic exercise training is an effective intervention to improve IR and VEF. PURPOSE: To determine changes in IR and VEF following aerobic exercise training in older OW/O adults. We hypothesized that 3 months of aerobic exercise training would improve IR and VEF, independent of weight loss. METHODS: Preliminary data are from 11 (8 women) older OW/O adults participating in a randomized clinical trial: 4 control (CON) (64±8 y; BMI=32.7±3.3 kg/m2, body fat=41.5±8.0%) and 7 exercisers (EX) (62±4 y; 32.2±5.5 kg/m2, 40.2±10.2%). Supervised aerobic exercise training consisted of moderate-intensity (40-60% heart rate reserve) cycling performed 3 d/wk for 3 months. Body mass and composition were measured by bioelectrical impedance analysis following an overnight fast. Brachial artery flow-mediated dilation (FMD), a non-invasive measure of VEF that predicts incident CVD events, was assessed by a trained technician using high-resolution ultrasonography. HOMA-IR was calculated from fasting blood glucose and insulin. RESULTS: No between group differences were detected at baseline. Compared to baseline, no changes were found in CON at 3 months (all P≥0.19). However, percent body fat (40.2±10.2% vs. 38.9±10.4% for baseline vs. 3 months, respectively (P<0.05)) and brachial artery FMD (3.2±3.0% vs. 5.1±2.8% (P<0.05)) improved at 3 months in EX. No other time effects were found in EX. CONCLUSIONS: Preliminary data from our ongoing clinical study show that 3 months of moderate-intensity aerobic exercise training improves body composition and VEF in OW/O older adults. Continued recruitment of participants completing a longer exercise training program (i.e., 6 months) will more definitely determine the beneficial impact of aerobic exercise training on VEF and related cardiometabolic risk factors.

Brain Perfusion Change in Patients with Mild Cognitive Impairment After 12 Months of Aerobic Exercise Training.

Aerobic exercise (AE) has recently received increasing attention in the prevention of Alzheimer's disease (AD). There is some evidence that it can improve neurocognitive function in elderly individuals. However, the mechanism of these improvements is not completely understood. In this prospective clinical trial, thirty amnestic mild cognitive impairment participants were enrolled into two groups and underwent 12 months of intervention. One group (n = 15) performed AE training (8M/7F, age = 66.4 years), whereas the other (n = 15) performed stretch training (8M/7F, age = 66.1 years) as a control intervention. Both groups performed 25-30 minutes training, 3 times per week. Frequency and duration were gradually increased over time. Twelve-month AE training improved cardiorespiratory fitness (p = 0.04) and memory function (p = 0.004). Cerebral blood flow (CBF) was measured at pre- and post-training using pseudo-continuous-arterial-spin-labeling MRI. Relative to the stretch group, the AE group displayed a training-related increase in CBF in the anterior cingulate cortex (p = 0.016). Furthermore, across individuals, the extent of memory improvement was associated with CBF increases in anterior cingulate cortex and adjacent prefrontal cortex (voxel-wise p < 0.05). In contrast, AE resulted in a decrease in CBF of the posterior cingulate cortex, when compared to the stretch group (p = 0.01). These results suggest that salutary effects of AE in AD may be mediated by redistribution of blood flow and neural activity in AD-sensitive regions of brain.

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.

Effects of long-term aerobic training and detraining on functional capacity and quality of life in hemodialysis patients: A pilot study.

Although previous studies have shown the benefits of exercise training in hemodialysis patients, little is known about the effects of long-term of exercise program on these patients. We investigated the effects and the safety of long-term aerobic training and the effects of detraining on functional capacity and quality of life in hemodialysis patients. Ten patients were allocated to two groups: training and detraining. The training group completed at least 30 months of aerobic training, and the detraining group completed at least 20 months and then discontinued the training for at least 10 months. The outcomes were analyzed at baseline, after 3 months of aerobic training and at the 30-month follow-up. The training and detraining groups performed 37 (5.5) and 24 (3.0) months of aerobic training, respectively. The detraining group discontinued the training for 11.0 (2.0) months. After 3 months of aerobic training, six-minute walking test distance increased significantly in both groups (training group = 569 (287.8) vs 635.5 (277.0) m, p = 0.04; detraining group = 454.5 (72.3) vs 515.0 (91.8) m, p = 0.04). There was no significant difference in the six-minute walking test distance in the training group (576.5 (182.5), p > 0.05) and a significant decrease (436.2 (89.6) m, p = 0.04) in the detraining group at the follow-up compared to the third month of aerobic training. No significant difference was observed in quality of life during the study. No complications were found during the protocol of the exercise. These results suggest that long-term aerobic training is safe and can maintain functional capacity in hemodialysis patients. In contrast, detraining can result in loss of functional capacity in these patients.

Exercise effects on arterial stiffness and heart health in children with excess weight: The SMART RCT.

IntroductionChildhood obesity and inactivity are associated with cardiovascular risk. Evidence is limited for exercise effects on arterial health in children.MethodsOne hundred seventy-five inactive children with overweight or obesity (8–11 years, ≥85th percentile BMI, 61% female, 87% Black, 73% with obesity) were randomized to an 8-month daily after-school aerobic exercise program (40 min/d, n=90) or a sedentary control condition (n=85). Carotid-femoral pulse wave velocity (PWV, primary outcome, arterial stiffness), fitness, adiposity, blood pressure (BP), glucose, insulin resistance, lipids, and C-reactive protein were measured at baseline and posttest (8 months). Adiposity, fitness, and BP were measured again at follow-up, 8–12 months later. Intent-to-treat analyses were conducted using mixed models.ResultsThe study had 89% retention, with attendance of 59% in exercise and 64% in the control condition, and vigorous exercise participation (average heart rate 161±7 beats/min). Compared to controls, the exercise group had twice the improvement in fitness (VȮ2 peak, 2.7 (95% CI 1.8, 3.6) vs. 1.3 (0.4, 2.3) ml/kg/min) and adiposity (−1.8 (−2.4, −1.1) vs. −0.8 (−1.5, -0.1)%), each p=0.04, and a large improvement in HDL-cholesterol (0.13 (0.075, 0.186) vs. -0.028 (−0.083, 0.023) mmol/l, p<0.0001). There was no group×time effect on other outcomes at 8 months, or on any outcomes at follow-up. The change in PWV at 8 months correlated with changes in insulin and insulin resistance (both r=0.32), diastolic BP (r=0.24), BMI (r=0.22) and adiposity (r=0.18).ConclusionsEight months of aerobic exercise training improved fitness, adiposity, and HDL-cholesterol levels, but did not reduce arterial stiffness in children with excess weight. PWV improved as a function of insulin resistance, BP, BMI and adiposity. Weight loss may be required to improve arterial stiffness. Exercise benefits waned after discontinuing the program.Trial RegistrationThis study is registered at www.clinicaltrials.gov NCT02383485.

Exercise Training in Amnestic Mild Cognitive Impairment: A One-Year Randomized Controlled Trial.

The current evidence is inconclusive to support the benefits of aerobic exercise training (AET) for preventing neurocognitive decline in patients with amnestic mild cognitive impairment (aMCI). To examine the effect of a progressive, moderate-to-high intensity AET program on memory and executive function, brain volume, and cortical amyloid-β (Aβ) plaque deposition in aMCI patients. This is a proof-of-concept trial that randomized 70 aMCI patients to 12 months of AET or stretching and toning (SAT, active control) interventions. Primary neuropsychological outcomes were assessed by using the California Verbal Learning Test-second edition (CVLT-II) and the Delis-Kaplan Executive Function System (D-KEFS). Secondary outcomes were the global and hippocampal brain volumes and the mean cortical and precuneus Aβ deposition. Baseline cognitive scores were similar between the groups. Memory and executive function performance improved over time but did not differ between the AET and SAT groups. Brain volume decreased and precuneus Aβ plaque deposition increased over time but did not differ between the groups. Cardiorespiratory fitness was significantly improved in the AET compared with SAT group. In amyloid positive patients, AET was associated with reduced hippocampal atrophy when compared with the SAT group. The AET and SAT groups both showed evidence of slightly improved neuropsychological scores in previously sedentary aMCI patients. However, these interventions did not prevent brain atrophy or increases in cortical Aβ deposition over 12 months. In amyloid positive patients, AET reduced hippocampal atrophy when compared with the SAT group.

Effects of Aerobic Exercise on Atherosclerotic Risk in Postmenopausal Women

To study the effects of aerobic exercise on lipid metabolism, endothelial function, and oxidative stress reaction in postmenopausal women, in order to prevent and control atherosclerosis. Thirty-two women with natural menopause were randomly divided into an exercise group and a control group. Participants in the exercise group (n = 16) took part in a 3-month aerobic training program according to their exercise prescription, while participants in the control group (n = 16) maintained their usual lifestyles. Lipids, endothelial function, and oxidative stress-related indicators were measured before and after the intervention. After 3 months of aerobic training at an intensity of 50–60% of cardiorespiratory fitness, serum total cholesterol and low-density lipoprotein cholesterol decreased significantly (P < 0.05), and high-density lipoprotein cholesterol increased significantly (P < 0.01). A significant reduction in endothelin (P < 0.01) and a significant increase in nitric oxide (P < 0.05) were also observed. The training intervention also delayed the increase in homocysteine and cysteine aspartate-specific protease-3 in postmenopausal women. Aerobic exercise had a positive effect on blood lipids, endothelial function, and oxidative stress of postmenopausal women, and these changes may mitigate the risk of atherosclerosis occurrence. Similar exercise programs could be used as a primary atherosclerosis prevention strategy for postmenopausal women.

The Effect of Short- and Long-Term Aerobic Training Years on Systemic O2 Utilization, and Muscle and Prefrontal Cortex Tissue Oxygen Extraction in Young Women

Buzza, G, Lovell, GP, Askew, CD, and Solomon, C. The effect of short- and long-term aerobic training years on systemic O2 utilization, and muscle and prefrontal cortex tissue oxygen extraction in young women. J Strength Cond Res 33(8): 2128-2137, 2019-This study aimed to determine if systemic O2 utilization (VO2) and tissue oxygen extraction (deoxyhemoglobin [HHb]) in the vastus lateralis (VL), gastrocnemius (GAST), and prefrontal cortex were different during exercise between short-term trained (STT, 6-24 months) and long-term trained (LTT, >5 years) young women while controlling for current training load. Thirteen STT and 13 LTT participants completed ramp incremental (RI) and square-wave constant load (SWCL) tests on a cycle ergometer. In LTT compared with STT: (a) VO2 was higher during the RI (p = 0.024) and SWCL (p = 0.001) tests; (b) HHb in the VL (p = 0.044) and GAST (p = 0.027) was higher in the RI test; and (c) there were significant group × intensity interactions for VO2 in the SWCL test. The additional years of aerobic training in LTT compared with STT (LTT 7.1 ± 1.9 vs. STT 1.5 ± 0.4 years) resulted in higher VO2 and HHb in the VL and GAST. These results indicate that in young women, independent of current training load, systemic VO2 and peripheral muscle O2 extraction during exercise continues to increase beyond 24 months of aerobic training.

Cognitive Effects of Adding Caloric Restriction to Aerobic Exercise Training in Older Adults with Obesity.

ObjectiveThis study examined the short and long-term effects of adding caloric restriction to five months of aerobic exercise training on executive function in sedentary older adults with obesity.MethodsSedentary years adults with obesity aged 65–79 completed a randomized trial investigating the cardiorespiratory benefits of adding moderate (~250kcal) or high (~600kcal) caloric restriction to a 20-week aerobic exercise program. Approximately half (n=88) completed a cognitive assessment battery at baseline, post-intervention, and 18–24 months after intervention completion. The primary outcome was an executive function composite score.ResultsIn the overall sample, the executive function composite increased 0.114 from baseline to post-intervention (p=0.01). Randomization to caloric restriction did not significantly alter executive function over aerobic exercise alone, nor were there between-group differences on any individual executive function test at post-intervention or long-term follow-up. Adding caloric restriction to exercise was associated with a modest increase in MMSE score (p=0.04). In the overall sample, increases from baseline at long-term follow-up were noted in digit symbol and word list recall performance as well.ConclusionsAdding caloric restriction to a 20-week aerobic exercise program does not worsen or improve executive function more than exercise alone assessed up to 24 months post-randomization.