Continuous Moderate Intensity Research Articles

Performance on a domain-general and a domain-specific cognitive task during exercise: what are the effects of exercise intensity, exercise modality, and time of cognitive assessment among highly-trained athletes?

ABSTRACT This study examined cognitive performance during exercise and the effects of exercise intensity, exercise modality, cognitive task type, and time of assessment, as well as assessed the accompanying self-reported measures. Eighteen highly-trained and elite water polo players (21.04 ± 3.27 years of age; 12 male, 6 female) completed a dual-task protocol on two occasions: once performing a domain-general task (Stroop test with three cognitive trial types) and once performing a domain-specific task (water polo video-based test) during cycling exercise. The exercise involved three work-matched bouts of cycling: continuous moderate intensity, continuous high intensity, and interval high intensity. Self-reported measures (rating of perceived exertion, affect, mental effort, mental and physical demands) were recorded after each exercise condition. There were exercise intensity-related effects on Stroop performance only, including faster reaction time during moderate-intensity exercise for naming trials (p < 0.001), and interactions with cognitive trial type (p = 0.037). There were no differences between continuous and interval high-intensity exercise conditions for either performance or self-reported responses. Notably, mental effort and demand, in addition to physical effort and demand, were perceived to be significantly higher for the Stroop task than for the video-based test despite identical exercise conditions. Furthermore, Stroop accuracy was associated with more positive affect (r = 0.47) and lower ratings of physical demand (r = −0.37). These findings imply possible task-specificity of athletes’ dual-task performance. They also support the importance of further exploring how task duration and participants' perceptions relate to executive function performance during exercise.

Impact of pre- and post-exercise strategies on hypoglycemic risk for two modalities of aerobic exercise among adults and adolescents living with type 1 diabetes using continuous subcutaneous insulin infusion: A randomized controlled trial.

We investigated strategies to mitigate hypoglycemic risk during and after different aerobic exercises in people with type 1 diabetes (pwT1D) using continuous subcutaneous insulin infusion. Thirty-seven pwT1D (21 adults, 16 adolescents; HbA1c = 7.5 ± 1.0 %) participated in two post-absorptive (4-h post-meal) exercise sessions (60-min continuous moderate intensity [CONT] vs. intermittent [INT]). Pre-exercise basal rate reduction (BRR) was either 40 % or 80 %, 90 min before exercise. Post-exercise, participants undertook either a 20 % BRR for 10 h with 20 % reduced dinner bolus (INS) or a 45 g post-exercise carbohydrate (CHO) snack with a 50 % insulin bolus, and a 30 g bedtime CHO snack without bolus (snack). While a similar number of hypoglycemic events (31 vs. 28) were observed between exercise modalities, CONT led to a greater decrease in blood glucose during exercise compared to INT (-3.1 ± 2.3, CONT vs. -2.7 ± 2.2 mmol/l, INT, P = 0.005). Changes in blood glucose during exercise (-3.0 ± 2.4, 40 %BRR vs. -2.8 ± 2.1 mmol/l, 80 %BRR, P = 0.076) and the number of hypoglycemic events (35 vs. 24) were similar between 40 % and 80 %BRR. Time in hyperglycemia was lower with INS compared to snack in the first 30 min after exercise, but no differences were observed for late recovery period or nighttime. Compared to INT, CONT led to greater blood glucose decline without increasing hypoglycemia risk. A larger pre-exercise BRR did not further reduce hypoglycemia risk during exercise. Post-exercise INS and snack strategies led to comparable glucose profiles in pwT1D.

Acute endothelial, blood pressure, and glycemic responses after aerobic sessions in type-2 diabetic with hypertension: A double-blinded randomized study

ObjectivesTo compare the acute response of moderate intensity continuous exercise (MICE) vs moderate intensity interval exercise (MIIE) on endothelial function, post-exercise hypotension (PEH), and glycemia in type 2 diabetes (T2DM) with hypertension. MethodsTwelve T2DM (aged 52.8 ± 3.8 years old) patients with hypertension underwent a randomized cross-over study following isocaloric (200 kcal) protocols: (i) MICE: walk-jogging at 50% of VO2peak, (ii) MIIE session: walking – jogging (stimulus/recovery – 3:3 min each) at 60% of VO2peak followed by recovery at 40% of VO2peak, and (iii) control (CON): lying quietly in a supine position for 30 min. A generalized estimating equation was utilized to verify possible differences over time × session. ResultsThe %FMD (Baseline: 3.59 ± 1.58 vs. 30 min: 6.73 ± 4.34) and the absolute FMD changed after MIIE (Baseline: 0.16 ± 0.10 vs. 30 min: 0.17 ± 0.14). Only absolute FMD changed after MIIE (Baseline: 0.14 ± 0.07 vs. 30 min: 0.16 ± 0.07). Besides, MIIE at 30 min provides higher absolute FMD values when compared to baseline from MICE and baseline, 30 min, and 60 min from control. Regarding blood pressure, no PEH statistical main effect was found. Finally, the glycemia changed at baseline vs. 30 min and 60 min after MIIE (210.5 ± 9.4 vs. 127.6 ± 10.0 and 120 ± 8.9), MICE (219.5 ± 12.7 vs. 125.2 ± 12.0 and 118.2 ± 11.6), and control sessions (215.9 ± 11.8 vs. 187.4 ± 11.2 and 172.6 ± 11.3 mg/dL, p < 0.05). However, MIIE and MICE showed higher decreases compared to the control. ConclusionsMIIE and MICE sessions are similar and effective exercise strategies to induce changes in endothelial function and glycemic responses in type-2 diabetics with hypertension.

Acute natural killer cells response to a continuous moderate intensity and a work-matched high intensity interval exercise session in metastatic cancer patients treated with chemotherapy

BackgroundIt has been suggested that the acute natural killer (NK) cell response to aerobic exercise might contribute to the tumor suppressor effect of regular exercise observed in preclinical studies. Moreover, because this response is modulated by exercise intensity, high-intensity intervals exercise (HIIE) might represent an interesting therapeutic approach in cancer patients. However, this immune response remains unstudied in cancer patients currently undergoing chemotherapy. ObjectiveTo characterize the acute NK cell response following a moderate-intensity continuous aerobic exercise session (MOD), and a HIIE session in metastatic cancer patients treated with chemotherapy. MethodsTwelve cancer patients (45–65 years old) underwent a MOD and a duration and work-matched HIIE trial, in a block-randomized order. Peripheral blood mononuclear cells (PBMC) were isolated before, after and 1h after each trial. NK cell subsets were enumerated using flow cytometry and complete blood counts. The surface expression of the cytotoxic NK cell (cNK; CD56dimCD16+) subset was evaluated for its expression of the differentiation markers CD57 and CD158a, the activating receptor NKG2D, the immune checkpoints TIM-3 and PD-1, and the chemokine receptors CXCR3, CXCR4 and CCR2. ResultscNK cell blood counts increased immediately following MOD (p < 0.001) and decreased back to pre-exercise values 1 h after exercise cessation (p < 0.001). The most responsive cNK cell subsets were expressing CD57, CD158a, NKG2D, TIM-3 and CXCR3. The HIIE trial elicited a similar biphasic response, without any difference between trials (all p ≥ 0.38). However, significant changes in the MFI values of CXCR4 and NKG2D were observed in the cNK cell subset following HIIE (all p ≤ 0.038), but not MOD. ConclusionIn metastatic cancer patients undergoing chemotherapy, both MOD and HIIE can elicit an acute mobilisation and egress of NK cells exhibiting phenotypic characteristics associated with high cytotoxicity and tumor homing. Future longitudinal trials are needed to determine if combining aerobic exercise training and chemotherapy will translate towards favorable immune and clinical outcomes.

Greater glycemic control following low-load, high-repetition resistance exercise compared with moderate-intensity continuous exercise in males and females: a randomized control trial.

Exercise has long been known for its beneficial effects on insulin sensitivity (IS) and glucose handling with both moderate-intensity continuous (MIC) exercise and resistance exercise (RE) inducing beneficial effects. In recent years, low-load, high-repetition (LLHR) RE has emerged as a strategy to increase muscle mass and strength to levels similar to traditional RE; however, the effects of LLHR RE on glucose handling has yet to be investigated. The purpose of this trial was to compare the acute effects of LLHR RE to MIC exercise on post-exercise glycemic control and insulin sensitivity in males and females. Twenty-four (n=12/sex) participants completed acute bouts of MIC exercise (30 min at 65% V̇O₂peak) and LLHR (3 circuits, 6 exercises/circuit, 25-35 repetitions/exercise/circuit) matched for time with muscle biopsies immediately pre and post exercise and an oral glucose tolerance test (OGTT) 90 min following exercise. Blood glucose concentrations (p=0.002, ηp 2=0.37), glucose AUC (p=0.002, ηp 2=0.35) and max glucose concentration (p=0.003, ηp 2=0.34) were lower during the post exercise OGTT following LLHR RE compared to MIC exercise. There was a main effect of trial on TBC1D1 Ser237 phosphorylation (p=0.04, ηp 2=0.19) such that it was greater following MIC exercise compared to LLHR RE. Furthermore, phosphorylated ACC Ser79 increased following MIC exercise with no change following LLHR RE (p<0.001, ηp 2=0.50). Phosphorylation of PTEN Ser380 was greater in males than females during LLHR RE (p=0.01, ηp 2=0.27). These findings suggest that LLHR RE is a feasible exercise modality to improve post-exercise glycemic control in both males and females. Trial registration number: NCT06217679.

Acute effects of high intensity interval training versus moderate intensity continuous training on haemostasis in patients with coronary artery disease

Exercise training is associated with an acute net increase in coagulation, which may increase the risk of atherothrombosis in coronary artery disease (CAD) patients. We sought to compare the acute haemostatic effects of a bout of moderate-intensity continuous (MICT) and high-intensity interval training (HIIT) in patients with CAD. Patients after a recent myocardial infarction were randomized into a HIIT or MICT session of exercise training on a stationary bike. Blood was sampled at baseline, after the exercise bout and after a one-hour resting period. We measured overall haemostatic potential (OHP), overall coagulation potential (OCP), fibrinogen, D-dimer and von Willebrand factor (vWF) and calculated overall fibrinolytic potential (OFP). Linear mixed models for repeated measures were constructed to assess the treatment effect. A total of 117 patients were included. OCP, OHP, fibrinogen, D-dimer and vWF significantly increased after exercise and returned to baseline after a one-hour rest, OFP decreased after exercise and returned to baseline levels after a one-hour rest. Linear mixed models showed a significant difference between HIIT and MICT in fibrinogen (p 0.043) and D-dimer (p 0.042). Our study has shown that an exercise bout is associated with a transient procoagulant state in patients with CAD, with similar exercise-induced haemostatic changes for HIIT and MICT.

Effects of Continuous Moderate Intensity Training (MICT) and Intermittent Calorie Restriction on Changes in Blood Sugar Levels and The Number of Pancreatic Beta Cells of Female Mice Pancreas (Mus Musculus) on A High Glycemic Index Diet

Effects of Continuous Moderate Intensity Training (MICT) and Intermittent Calorie Restriction on Changes in Blood Sugar Levels and The Number of Pancreatic Beta Cells of Female Mice Pancreas (Mus Musculus) on A High Glycemic Index Diet

Effects of Specific Bioactive Collagen Peptides in Combination with Concurrent Training on Running Performance and Indicators of Endurance Capacity in Men: A Randomized Controlled Trial

BackgroundFirst evidence indicates that the supplementation of specific collagen peptides (SCP) is associated with a significant improvement in running performance in physically active women; however, it is unclear if the same is true in males. The purpose of the present study was to investigate the effects of a concurrent training program including 60 min of continuous moderate intensity running training and 15 min of dynamic resistance training combined with supplementation of SCP on parameters of running performance in moderately trained males.MethodsIn a double-blind, placebo-controlled, randomized trial, participants performed a 12 weeks concurrent training and ingested 15 g of SCP [treatment group (TG)] or placebo [control group (CG)] daily. Before and after the intervention, running endurance performance was measured by a 1-h time trial on a running track. Velocity at the lactate threshold (VLT) and at the individual anaerobic threshold (VIAT) were assessed on a treadmill ergometer. Body composition was evaluated by bioelectrical impedance analysis.ResultsThirty-two men (28.4 ± 5.2 years) completed the study and were included in the analysis. After 12 weeks, TG had a statistically significant (p ≤ 0.05) higher increase in running distance (1727 ± 705 m) compared to the CG (1018 ± 976 m) in the time trial. VLT increased in the TG by 0.680 ± 1.27 km h−1 and slightly decreased by − 0.135 ± 0.978 km h−1 in the CG, resulting in statistically significant group differences (p ≤ 0.05). A significantly higher improvement in VIAT (p ≤ 0.05) was shown in the TG compared with the CG only (1.660 ± 1.022 km h−1 vs 0.606 ± 0.974 km h−1; p ≤ 0.01). Fat mass decreased (TG − 1.7 ± 1.6 kg; CG − 1.2 ± 2.0 kg) and fat free mass increased (TG 0.2 ± 1.2 kg; CG 0.5 ± 1.3 kg) in both groups with no significant group differences.ConclusionIn summary, supplementation with 15 g of SCP improved running performance in a 1-h time trial and enhanced indicators of endurance capacity at submaximal exercise intensities such as an increased velocity at the lactate as well as the anaerobic threshold more effectively than CT alone.Trial registration: ETK: 123/17; DRKS-ID: DRKS00015529 (Registered 07 November 2018—Retrospectively registered); https://drks.de/search/de/trial/DRKS00015529

Impact of high-intensity interval hyperpnea on aerobic energy release and inspiratory muscle fatigue

Respiratory muscle endurance training reportedly has beneficial effects on whole-body endurance performance. We produced a novel high-intensity interval (HII) protocol and characterized the associated physiological responses and respiratory muscle fatigue. Peak oxygen uptake of respiratory muscle (V̇O2peakRM) was estimated during the respiratory incremental test. The HII session consisted of five 3-minute hyperpnea periods at 100%V̇O2peakRM interspersed with 2-minute periods at 40%V̇O2peakRM (25 min total). The high-intensity continuous (HIC) session involved a single time-to-end bout of hyperpnea at 100%V̇O2peakRM. The moderate-intensity continuous (MIC) session involved 25 min of hyperpnea at 60% of maximal voluntary ventilation. V̇O2RM was recorded continuously, and maximal inspiratory pressure (PImax) was assessed before and after the sessions. HII session: V̇O2RM gradually increased as the sets proceeded, whereas PImax decreased significantly. HIC session: V̇O2RM increased progressively, and the time to end was 6.5 ± 0.5 min. PImax decreased significantly. MIC session: V̇O2RM did not change for 25 min, and PImax remained unchanged. The duration of V̇O2RM at near- and supra-maximal levels in the HII session (10 ± 1 min) was longer than that in the HIC session (4 ± 1 min). The decrease in PImax was larger in the HII session (−12 ± 3 %) than MIC session (−4 ± 3 %). The HII protocol is characterized by a longer time to maximally stimulate the aerobic energy system of respiratory muscle than the HIC protocol and greater inspiratory muscle fatigue than the traditional MIC protocol. These results suggest that the HII protocol could enhance the efficacy of respiratory muscle training programs.

578-P: Effect of Two Timings for Postprandial Exercise Onset on Hypoglycemic Risk in Adults Living with Type 1 Diabetes

Introduction: To limit hypoglycemic risk of during postprandial aerobic exercise the importance of reducing prandial insulin dose have been established with exercise starting 90-min after the meal. People with type 1 diabetes also exercise closer or further away of their mealtime and hypoglycemic risk associated with those timings may be different. Objective: We aimed to evaluate the effect of two different timings for exercise onset (60-min vs. 120-min post-meal) during moderate intensity exercise. Methods: 37 participants (25 M/ 12 F; HbA1c: 7.4 ± 0.9%) received an ultra-rapid insulin dose reduced by 50% and performed 1 hour of continuous moderate intensity exercise (at 60% of VO2peak) started either 60-min (EX60min) or 120-min (EX120min) after breakfast. Venous blood glucose was measured every 10-min during exercise. Results: Decrease in blood glucose between exercise onset and nadir (lowest point during exercise) was more important with EX120min (-68.5 ± 43.2 mg/dL, EX60min vs. -75.7 ± 39.6 mg/dL, EX120min, p=0.015). The number of hypoglycemic events during exercise and during recovery (90-min post-exercise) were similar between EX60min and EX120min (3 vs. 4 and 3 vs. 0, respectively). Postprandial glucose excursion before exercise onset was reduced with Ex60min compared to Ex120min. Conclusion: For postprandial aerobic exercise, with a reduced insulin meal bolus, hypoglycemic risk is comparable if exercise is started at 60 or 120min after the meal. Guidelines established with exercise starting 90min after the meal can probably be used for earlier or later timing. Disclosure J.Molveau: None. É.Myette-côté: None. S.Tagougui: None. N.Taleb: Consultant; Viatris Inc. E.Heyman: None. C.Suppere: None. R.Rabasa-lhoret: Consultant; Dexcom, Inc., Abbott, Janssen Pharmaceuticals, Inc., Novo Nordisk Canada Inc., Sanofi, Lilly, Tandem Diabetes Care, Inc., Insulet Corporation.

Does Higher Intensity Increase the Rate of Responders to Endurance Training When Total Energy Expenditure Remains Constant? A Randomized Controlled Trial

BackgroundStandardized training prescriptions often result in large variation in training response with a substantial number of individuals that show little or no response at all. The present study examined whether the response in markers of cardiorespiratory fitness (CRF) to moderate intensity endurance training can be elevated by an increase in training intensity.MethodsThirty-one healthy, untrained participants (46 ± 8 years, BMI 25.4 ± 3.3 kg m−2 and {dot{text{V}}}O2max 34 ± 4 mL min−1 kg−1) trained for 10 weeks with moderate intensity (3 day week−1 for 50 min per session at 55% HRreserve). Hereafter, the allocation into two groups was performed by stratified randomization for age, gender and VO2max response. CON (continuous moderate intensity) trained for another 16 weeks at moderate intensity, INC (increased intensity) trained energy-equivalent for 8 weeks at 70% HRreserve and then performed high-intensity interval training (4 × 4) for another 8 weeks. Responders were identified as participants with VO2max increase above the technical measurement error.ResultsThere was a significant difference in {dot{text{V}}}O2max response between INC (3.4 ± 2.7 mL kg−1 min−1) and CON (0.4 ± 2.9 mL kg−1 min−1) after 26 weeks of training (P = 0.020). After 10 weeks of moderate training, in total 16 of 31 participants were classified as VO2max responders (52%). After another 16 weeks continuous moderate intensity training, no further increase of responders was observed in CON. In contrast, the energy equivalent training with increasing training intensity in INC significantly (P = 0.031) increased the number of responders to 13 of 15 (87%). The energy equivalent higher training intensities increased the rate of responders more effectively than continued moderate training intensities (P = 0.012).ConclusionHigh-intensity interval training increases the rate of response in VO2max to endurance training even when the total energy expenditure is held constant. Maintaining moderate endurance training intensities might not be the best choice to optimize training gains.Trial Registration German Clinical Trials Register, DRKS00031445, Registered 08 March 2023—Retrospectively registered, https://www.drks.de/DRKS00031445

Exercise-induced responses in matrix metalloproteinases and osteopontin are not moderated by exercise format in males with overweight or obesity

PurposeMatrix metalloproteinase-2 (MMP-2) and -3 (MMP-3), and osteopontin (OPN) are associated with adipose-tissue expansion and development of metabolic disease. The purpose of the current study was to assess the circulating concentration of these markers, along with adiponectin and glucose concentrations, in response to acute exercise in individuals with overweight or obesity.MethodsFourteen sedentary males with overweight or obesity (29.0 ± 3.1 kg/m2) completed two separate, 3-day trials in randomised and counterbalanced order. An oral glucose tolerance test (OGTT) was performed on each day of the trial. Day two of each trial consisted of a single 30 min workload-matched bout of either high-intensity interval exercise (HIIE; alternating 100% and 50% of peak pulmonary oxygen uptake, mathop {text{V}}limits^{.}O2peak) or continuous moderate intensity (CME; 60% mathop {text{V}}limits^{.}O2peak) cycling completed 1 h prior to the OGTT. Glucose and physical activity were continuously monitored, while MMP-2, MMP-3, OPN and adiponectin were measured pre-, 0 h post-, 1 h post- and 25 h post-exercise.ResultsExercise transiently increased MMP-3 and decreased OPN (both p < 0.01), but not MMP-2 or adiponectin. There were no differences in the response of inflammatory markers to the different exercise formats. Exercise increased mean daily glucose concentration and area under the glucose curve during the OGTT on Day 2 and Day 3 (main effect of time; p < 0.05).ConclusionAcute cycling exercise decreased OPN, which is consistent with longer term improvements in cardiometabolic health and increased MMP-3, which is consistent with its role in tissue remodelling. Interestingly, exercise performed prior to the morning OGTT augmented the glucose concentrations in males.Trial registrationACTRN12613001086752.

Effect of High-Intensity Interval, Moderate-Intensity Continuous, and Self-Selected Intensity Training on Health and Affective Responses

ABSTRACT Purpose: To compare the effects of 12-week high-intensity interval (HIIT), moderate-intensity continuous (MICT), and self-selected intensity training (SSIT) on health outcomes and affective responses. Methods: Seventy-three overweight/obese inactive adults (62% woman; age, 31.4 ± 7.2 years; height, 1.66 ± 0.09 cm; Body mass index, 28.9 ± 2.7 kg.m−2) who were randomized into HIIT (n = 23), MICT (n = 24) and SSIT (n = 26) groups. The training was conducted three times per week in an outdoor environment, with 4 weeks under direct supervision and 8 weeks with semi-supervision. Cardiorespiratory fitness, body composition, and metabolic profile were evaluated at baseline and at the end of the 4th and 12th weeks. Core affect was measured during all training sessions. Results: Peak oxygen uptake improved in all groups after 4 and 12 weeks compared with baseline. Only the SSIT had reductions in body fat throughout the intervention. No improvements were observed in the metabolic profile across all groups. SSIT was perceived as more pleasurable than HIIT; however, there were no differences in affective responses between SSIT and MICT. Affective responses in-task (e.g. negative and positive peak, rate of change and affect at the end of the exercise session) predicted the HIIT and SSIT exercises attendance rate. Conclusion: Regardless of the exercise training protocol, overweight/obese inactive adults improved health outcomes, which suggests the prescribing HIIT, MICT, and SSIT in outdoor environments. SSIT should be considered in order to optimize the pleasure during training sessions. Affective response more positive in-task of the HIIT and SSIT is associated with greater attendance rate in these exercise protocols.

Effect of 4 Weeks Preconditioning with High Intensity Interval Training and Moderate Intensity Continuous Training on Brain Levels of TNF-Α and TLR4 in Male Wistar Rats

Introduction: Inflammation in the brain is known as neuroinflammation and increases TNF-α (Tumor necrosis factor alpha) secretion and activates the TLR4 (Toll-like receptor 4) pathway. The aim of this study was to evaluate the effect of 4 weeks preconditioning with high intensity intermittent training (HIIT) and moderate intensity training (MICT) on TNF-α and TLR4 levels in male Wistar rats.&#x0D; Methods: The current research was an experimental study.18 male Wistar rats were divided into three groups: high intensity intermittent training (6 heads), continuous moderate intensity training (6 heads) and the control group (6 heads). HIIT program included 6 stages of 2-minute activity with intensity of 85-90% VO2max and 5 stages of active rest for 2 minutes and MICT program with intensity of 65% VO2max with the same duration as HIIT for 4 weeks and 5 days per week was implemented. 48 hours after the last training session, rats were dissected and cortical tissues and layers of mice were extracted for TNF-α and TLR-4 using western blotting. Data analysis was performed using ANOVA test at a significance level of 0.05 With the help of SPSS version 16 software.&#x0D; Results: The results of the present study showed that TNF-α and TLR4 in the cortex and stratum cerebral areas after 4 weeks of high-intensity and moderate-intensity intermittent aerobic exercise did not change significantly compared to the control group (p≥0.05).&#x0D; Conclusion: According to these findings, it can be stated that exercise with high or moderate intensity cannot be an effective factor in increasing inflammatory markers in the brain.

The Effect of a 12 Week Mixed-Modality Training Intervention on the Cardio-Metabolic Health of Rotational Shift Workers

PurposeTo assess the effect of a 12 week resistance or aerobic training intervention on markers of cardio-metabolic function and sleep among male rotational shift workers.MethodThirty-eight sedentary, apparently healthy, male rotational shift workers were recruited and randomly allocated to a non-exercise control (CON) group, 3 sessions/week of moderate intensity continuous (MICT), or resistance training (RT) for 12 weeks in a semi-supervised setting. Pre- and post-testing assessed markers of cardio-metabolic function including peak oxygen uptake (VO2peak), glucose metabolism, insulin sensitivity, body composition, inflammatory markers, and 14 day actigraphy sleep assessment.ResultsMean session attendance across the intervention was 25 (± 7) of a possible 36 sessions. A significant group by time interaction was observed for MICT, with lower c-reactive protein (CRP) values observed post-training (P = 0.049). A significant effect for time was observed for both MICT (n = 9; P = 0.04) and RT (n = 10; P = 0.021), increasing total sleep time (TST) following a night shift post-intervention. Data redistribution regarding exercise adherence: < 24 (N-ADHERE) or ≥ 24 (ADHERE) resulted in significant pre-to-post reduction in body fat (P = 0.024) and fat mass percentage (P = 0.014) among ADHERE. No differences were observed for any intervention group on insulin sensitivity, glucose metabolism or oxygen uptake.ConclusionThe results of the current study support exercise as a valid intervention to improve the cardio-metabolic health of rotational shift workers. Average sessional attendance suggests shift workers face barriers to exercise that may need to be addressed to improve health outcomes.

Effect of caffeine on mitochondrial biogenesis in the skeletal muscle - A narrative review.

Caffeine is one of the most widely used substances as recreational drug for performance-enhancement in sport, underpinned by a strong evidence base. Although the effects of caffeine are widely investigated within the scope of performance physiology, the molecular effects of caffeine within skeletal muscle remain unclear. Evidence from invitro and invivo models suggest that caffeine regulates the glucose metabolism in the skeletal muscle. Moreover, caffeine seems to stimulate CaMKII, PPARδ/β, AMPK and PGC1α, classical markers of exercise-adaptations, including mitochondrial biogenesis and mitochondrial content. This review summarizes evidence to suggest caffeine-effects within skeletal muscle fibers, focusing on the putative role of caffeine on mitochondrial biogenesis to explore whether caffeine supplementation might be a strategy to enhance mitochondrial biogenesis.

The role of Aerobic Exercise in Bronchial Asthma: A review

Purpose of review: Asthma occurs as one of the most prevalent chronic disorders among children and adults in developed nations. Poor asthma control persists despite international treatment guidelines, resulting in frequent school and job absences, emergency room visits, and hospitalizations. Numerous asthmatic patients cite exercise as an asthma trigger, which likely results in exercise avoidance as a strategy of symptom control. Emerging evidence suggests that regular aerobic exercise may assist improve certain elements of asthma control. This article reviews on the effects of regular aerobic exercise on significant asthma-related outcomes, including symptoms, lung function, and quality of life. Recent findings: Many Randomized Control Trial, systematic reviews and meta-analysis in recent years have found that regular exercise is safe for children and adults with asthma. Asthma symptoms and quality of life appear to benefit with aerobic exercise, although gains in lung function and airway hyper responsiveness have been less consistent. Summary: Our review showed that frequent continuous moderate intensity aerobic exercise improved asthma symptoms and quality of life. Swimming or treadmill exercises are good possibilities.

Effects of moderate-continuous and high-intensity interval aerobic training on cardiac function of spontaneously hypertensive rats.

The aim of this study was to verify the effects of moderate-intensity continuous (MICT) and high-intensity interval (HIIT) aerobic training on cardiac morphology and function and the mechanical properties of single cardiomyocytes in spontaneously hypertensive rats (SHR) in the compensated phase of hypertension. Sixteen-week-old male SHR and normotensive Wistar (WIS) rats were allocated to six groups of six animals each: SHR CONT or WIS CONT (control); SHR MICT or WIS MICT (underwent MICT, 30 min/day, five days per week for eight weeks); and SHR HIIT or WIS HIIT (underwent HIIT, 30 min/day, five days per week for eight weeks). Total exercise time until fatigue and maximum running speed were determined using a maximal running test before and after the experimental period. Systolic (SAP), diastolic (DAP), and mean (MAP) blood pressures were measured using tail plethysmography before and after the experimental period. Echocardiographic evaluations were performed at the end of the experimental period. The rats were euthanized after in vivo assessments, and left ventricular myocytes were isolated to evaluate global intracellular Ca2+ transient ([Ca2+]i) and contractile function. Cellular measurements were performed at basal temperature (~37°C) at 3, 5, and 7 Hz. The results showed that both training programs increased total exercise time until fatigue and, consequently, maximum running speed. In hypertensive rats, MICT decreased SAP, DAP, MAP, interventricular septal thickness during systole and diastole, and the contraction amplitude at 5 Hz. HIIT increased heart weight and left ventricular wall thickness during systole and diastole and reduced SAP, MAP, and the time to peak [Ca2+]i at all pacing frequencies. In conclusion, both aerobic training protocols promoted beneficial adaptations to cardiac morphology, function, and mechanical properties of single cardiomyocytes in SHR.

Exercise mode influences post-exercise glucose sensitivity and insulin clearance in young, healthy males and females in a sex-dependent manner: A randomized control trial.

Type 2 diabetes (T2D) risk is lower in females than males. It has been reported that females have greater pancreatic 𝛽‐cell function than males, which may at least in part contribute to the T2D risk in females. 𝛽‐cell function is influenced by exercise training; however, previous trials comparing 𝛽‐cell function between the sexes have not included participants matched for training status. Furthermore, the acute effects of different modes of exercise on 𝛽‐cell function, and whether sex inherently influences these effects, are largely unexamined. Males and females (12/sex) completed a 120‐min oral glucose tolerance test (OGTT) at rest (CON) and following acute bouts of high‐intensity interval exercise (HIIE), moderate intensity continuous (MIC) exercise, and low‐load high‐repetition (LLHR) resistance exercise to assess whether sex inherently influences baseline and/or post‐exercise pancreatic function in the absence of pathology. We found no sex differences in basal pancreatic 𝛽‐cell function. Females had greater basal insulin clearance following MIC exercise compared to males (p = 0.01) and males tended to have a higher potentiation ratio following HIIE (p = 0.07). Females also had lower glucose sensitivity following MIC exercise compared to HIIE (p = 0.007) and LLHR (p = 0.003). Insulin clearance during the OGTT was greater following HIIE as compared with CON and MIC exercise (p = 0.02). 2‐H oral glucose insulin sensitivity was greater following LLHR compared to CON (p = 0.01). Acute bouts of different modes of exercise do not differentially influence 𝛽‐cell function but do influence insulin clearance and insulin sensitivity. Therefore, sex and exercise mode interact to differentially influence insulin clearance and glucose sensitivity.

Dynamic lighting schedules to facilitate circadian adaptation to shifted timing of sleep and wake.

Circadian adaptation to shifted sleep/wake schedules may be facilitated by optimizing the timing, intensity and spectral characteristics of light exposure, which is the principal time cue for mammalian circadian pacemaker, and possibly by strategically timing nonphotic time cues such as exercise. Therefore, circadian phase resetting by light and exercise was assessed in 44 healthy participants (22 females, mean age [±SD] 36.2 ± 9.2 years), who completed 8-day inpatient experiments simulating night shiftwork, which included either an 8 h advance or 8 h delay in sleep/wake schedules. In the advance protocol (n = 18), schedules were shifted either gradually (1.6 h/day across 5 days) or abruptly (slam shift, 8 h in 1 day and maintained across 5 days). Both advance protocols included a dynamic lighting schedule (DLS) with 6.5 h exposure of blue-enriched white light (704 melanopic equivalent daylight illuminance [melEDI] lux) during the day and dimmer blue-depleted light (26 melEDI lux) for 2 h immediately before sleep on the shifted schedule. In the delay protocol (n = 26), schedules were only abruptly delayed but included four different lighting conditions: (1) 8 h continuous room-light control; (2) 8 h continuous blue-enriched light; (3) intermittent (7 × 15 min pulses/8 h) blue-enriched light; (4) 8 h continuous blue-enriched light plus moderate intensity exercise. In the room-light control, participants received dimmer white light for 30 min before bedtime, whereas in the other three delay protocols participants received dimmer blue-depleted light for 30 min before bedtime. Both the slam and gradual advance protocols induced similar shifts in circadian phase (3.28 h ± 0.37 vs. 2.88 h ± 0.31, respectively, p = .43) estimated by the change in the timing of timing of dim light melatonin onset. In the delay protocol, the continuous 8 h blue-enriched exposure induced significantly larger shifts than the room light control (-6.59 h ± 0.43 vs. -4.74 h ± 0.62, respectively, p = .02). The intermittent exposure induced ~60% of the shift (-3.90 h ± 0.62) compared with 8 h blue-enriched continuous light with only 25% of the exposure duration. The addition of exercise to the 8 h continuous blue-enriched light did not result in significantly larger phase shifts (-6.59 h ± 0.43 vs. -6.41 h ± 0.69, p = .80). Collectively, our results demonstrate that, when attempting to adapt to an 8 h overnight work shift, delay shifts are more successful, particularly when accompanied by a DLS with high-melanopic irradiance light stimulus during wake.