Bout Of Exercise Research Articles

The effects of acute exercise on emotional pattern separation in adolescents and young adults

Acute exercise has been associated with cognitive improvements, particularly in memory processes linked to the hippocampus, such as the ability to discriminate between similar stimuli, called hippocampal pattern separation. This can be assessed behaviorally with a mnemonic discrimination task and neurally with functional magnetic resonance imaging (fMRI). Additionally, previous research has shown an emotional modulatory effect on pattern separation, involving the amygdala. In this randomized between-subject study, we investigated whether a 10-minute bout of moderate-intensity exercise, compared to rest, could enhance pattern separation of neutral and emotional images in a group of healthy adolescents and young adults (n=53). Our results showed no significant effects of exercise on either mnemonic discrimination performance or neural activity in the hippocampus and amygdala. Additionally, arterial spin labeling (ASL) confirmed that there were no significant differences in cerebral blood flow between exercise and rest. We did observe worse discrimination for images with a higher similarity level and worse discrimination for highly similar positive images compared to negative and neutral images. However, there were no significant correlations between behavioral outcomes and neural activity. Exploratory analysis revealed a neural signal consistent with pattern completion in the bilateral CA1 and left CA3, but no evidence of pattern separation. Future studies should optimize the exercise characteristics necessary to robustly enhance pattern separation.

Training Status Influences Regulation of Muscle and PBMC TLR4 Expression and Systemic Cytokine Responses to Vigorous Endurance Exercise.

A bout of vigorous endurance exercise transiently activates Toll-like receptor 4 (TLR4) and reduces TLR4 protein expressed on peripheral blood mononuclear cells (PBMCs). Endurance training, on the other hand, reduces TLR4-mediated signaling and minimizes the physiological stress imposed by exercise. Less is known about what occurs in skeletal muscle regarding TLR4 regulation and signaling. Therefore, this study aimed to investigate the regulation of TLR4 expressed in different tissue types (PBMCs and skeletal muscle samples) between endurance-trained and untrained men following vigorous endurance exercise and determine the effect of training status on cytokine responses associated with TLR4 activation. Endurance-trained (n = 7) and untrained (n = 5) men cycled for 1-hr at their respiratory compensation point, with blood and skeletal muscle samples collected pre- and 3-hours post-exercise. In response to vigorous exercise, untrained men experienced a decrease in inhibitor of κBα (IκBα) protein (suggesting IκB degradation and the activation of TLR4-associated transcription factor NF-κB) and TLR4 protein levels, along with a simultaneous increase in TLR4 mRNA expression in both skeletal muscle and PBMCs. Moreover, this exercise session led to elevated levels of circulating interleukin-6, tumor necrosis factor-α, and interleukin-1β. Collectively, these results suggest a heightened TLR4-mediated signaling pathway in untrained men. However, no changes in these targets were observed in endurance-trained men, possibly indicating a potential mechanism by which regular endurance training blunts systemic inflammation. These findings highlight the potential of endurance training to mitigate TLR4-mediated signaling, such as systemic inflammation, and shed light on the effects of exercise on TLR4 expression in PBMCs and skeletal muscle.

Visceral Fat Affects Heart Rate Recovery but Not the Heart Rate Response Post-Single Bout of Vigorous Exercise: A Cross-Sectional Study in Non-Obese and Healthy Participants

Body composition could influence exercise physiology. However, no one has ever studied the effect of visceral fat (VF) on heart rate (HR) trends during and after exercise by using bioimpedance analysis (BIA). This study aims to investigate BIA variables as predictors of HR trends during vigorous exercise. Ninety-six participants (age 22.5 ± 4.8 years) were included in the data analysis. After performing BIA, the HR was recorded at three time points: baseline HR (BHR), peak HR (PHR) at the end of vigorous exercise, and resting HR (RHR) 1 min after the end of the exercise. After BHR, a 30 s squat jump test was performed. Linear regression analysis showed the body fat percentage and VF as a predictor of HR recovery post-exercise (p < 0.01). However, body weight has no association with HR recovery (p > 0.05). On the other hand, BIA variables were not associated with the variation of HR from the baseline to the end of the exercise. The results show that higher VF is associated with a slower HR recovery. To schedule a training program, it would be safer to monitor visceral fat before prescribing recovery time.

Effect of exercise on plasma insulin levels in individuals with type 1 diabetes: A systematic review and meta-analysis.

Current evidence of the impact of acute exercise on insulin levels in individuals with type 1 diabetes remains controversial. Therefore, we conducted a systematic review and meta-analysis to explore exercise-induced changes in insulin levels. We conducted a systematic review (until 05 November 2023) and meta-analysis exploring the effect of exercise on insulin concentration in individuals with type 1 diabetes. We included randomised cross-over studies for rapid-acting insulin and pre- and post-studies for long-acting insulin in individuals with type 1 diabetes performing any type of acute exercise and had a control condition. The exercise-induced change in insulin levels was the outcome of interest. When possible, the mean differences (MDs) in insulin levels were pooled using the DerSimonian and Laird random effect method. Risk of bias was assessed for each included study. Seventeen trials, encompassing 186 participants with type 1 diabetes, were included in the systematic review. Twelve out of 17 studies included participants on rapid-acting insulin regimens and used a cross-over design, whereas five out of 17 single-arm studies included participants on (ultra)long-acting insulin. Seven out of 12 studies on rapid-acting insulins and all the single-arm studies were at high risk of bias. Results suggest a statistically significant, small-to-moderate increase of rapid-acting insulin after 30 min of exercise (MD of 18.44 [95% CI 0.02; 36.86; I2 0%] pmol/L); meanwhile, findings on (ultra)long-acting insulin were inconclusive. A small-to-moderate increase of insulin levels in studies including rapid-acting insulin was found after a bout of physical exercise in individuals with type 1 diabetes. However, current gaps in high-quality evidence challenge our understanding of insulin kinetics around exercise.

Cardiorespiratory Responses to Flywheel-Based Inertial Training Squats With Varying Moments of Inertia.

Mitchinson, CJ, Best, S, Caruso, J, and Bollinger, LM. Cardiorespiratory responses to flywheel-based inertial training squats with varying moments of inertia. J Strength Cond Res XX(X): 000-000, 2024-Flywheel-based inertial training (FIT) has gained popularity as a means to enhance muscle hypertrophy. Other applications, such as aerobic exercise training, remain unexplored. The aim of this study was to determine the cardiorespiratory responses to acute FIT with varying moments of inertia (MOIs). Methods: Overall, 20 (10 M, 10 F) healthy, physically active subjects underwent maximal graded exercise testing and completed 3 bouts of FIT exercise (1 familiarization session and 2 identical data collection sessions). Subjects completed quarter squats (60° peak knee flexion) at a pace of 50 squats·minute-1 until volitional fatigue. Flywheel-based inertial training MOI was increased by 0.005 kg·m2 every 3 minutes until a final workload of 0.020 kg·m2. Heart rate and gas exchange data were collected continuously and averaged over the final 60 s of each stage. Data were analyzed by a linear mixed model. Results: During the final testing session, there was a main effect of MOI to increase heart rate (HR), V̇o2, and RER. Men displayed greater oxygen consumption, but asimilar %V̇o2peak compared with women. We noted a significant inertia × sex interaction where RER tended to be lesser in women at higher MOI. In the final stage of exercise (MOI: 0.020 kg·m2), HR and V̇o2 were approximately 75-80 and 55% of peak, respectively, and RER was approximately 0.95-1.00. Conclusions: FIT quarter squats elicit moderate HR and V̇o2 responses, but near-maximal RER suggests a novel metabolic training stimulus. This exercise may supersede thelactate threshold and may not be sustainable for prolonged times. The physiological and performance effects of training in this manner are unclear.

Effects of different postures on the hemodynamics and cardiovascular autonomic control responses to exercise in postural orthostatic tachycardia syndrome.

To assess the effects of two different body positions on the cardiovascular autonomic profile during a single bout of exercise in patients with postural orthostatic tachycardia syndrome (POTS). Thirteen patients with POTS and thirteen healthy controls (C) participated in the study. ECG, respiration, beat-by-beat arterial pressure and O2 consumption (VO2) were continuously recorded while on a cycle ergometer in supine and upright positions, before and during exercise (6min, 50 Watts). Spectral analysis of RR intervals and systolic arterial pressure (SAP) variability provided indexes of cardiac sympathovagal interaction (LF/HF ratio), cardiac vagal modulation (HFRR, high-frequency component of RR variability, ~ 0.25Hz), sympathetic vasomotor control (LFSAP, low-frequency component of SAP variability, 0.1Hz) and baroreflex sensitivity (BRS, αLF). While supine, patients with POTS showed lower HFRR and αLF, greater heart rate (HR), LF/HF and LFSAP, compared with C, suggesting cardiovascular sympathetic over-activity and reduced BRS. While sitting upright, POTS showed greater HR and reduced HFRR and αLF compared with C. During supine exercise, SAP, HR, LF/HF increased and HFRR and αLF decreased similarly in POTS and C. In POTS, upright sitting exercise was associated with slightly higher , a greater increase in HR whereas LFSAP was lower than in C. Upright exercise was associated with excessive enhancement of HR and a blunted increase of the sympathetic vasomotor control in POTS. Conversely, supine exercise-induced hemodynamic and autonomic changes similar in POTS and C, thus making supine exercise potentially more suitable for physical rehabilitation in POTS.

The effects of a short exercise bout on executive functions in healthy older adults

Regular physical activity is associated with healthier brains and improved cognition among older adults. Yet, the impact of a short bout of exercise on older adults’ cognition still is not fully clarified. The present study explored the effects of 20 min of moderate-intensity aerobic exercise (on a cycle ergometer) on cognition. Forty-eight healthy older adults were randomly assigned to an exercise or a control group and completed four cognitive tests: Affective Go/No-Go (AGN), Simple Reaction Time (SRT), Spatial Working Memory (SWM) and a Backward Counting task. Tests were administered prior to and immediately after 20 min of cycling (exercise group) or rest (control group). Mixed-design 2 × 2 ANOVAs indicated a significant interaction of Group x Session, for commission errors on the positive valence of the Affective Go/No-go task, indicating that the exercise group performed better on one aspect of this inhibition test after cycling (p = 0.004), while the control group’s performance declined after rest. A similar pattern was found for the SWM, with the exercise group showing a significantly better performance after the exercise both for total error (p = 0.027) and the strategy (p = 0.002), while no improvement was observed after rest (controls). The study suggests that inhibitory control functions and working memory may be improved by a single relatively short bout of moderate exercise. However, the null effects of exercise on the other cognitive measures indicate that the neurocognitive benefits of acute exercise for older adults may be selectively sensitive to exercise parameters and to specific aspects of cognition.

The effects of acute exercise intensity on memory: Controlling for state-dependence.

The present experiment evaluated the effects of varying intensities of acute exercise on free-recall memory performance while controlling for potential state-dependent effects. Forty-eight young adults completed a within-subject experiment involving seven primary laboratory visits. The encoding and retrieval phases were matched or mismatched by taking place either during rest or during a less than 5-min bout of acute exercise, and at moderate or vigorous intensity. We did not find evidence that the effects of acute exercise on memory were state-dependent but instead demonstrated that memory recall was greater when memory retrieval occurred during vigorous-intensity exercise compared to rest. These findings have important implications for the strategic placement of exercise during the phases of memory (e.g., acquisition, storage, retrieval) to optimize memory performance and suggest boundary conditions of state-dependent learning. We discuss various theoretical accounts (e.g., shift in metabolic resources across brain regions) to explain these findings.

Acute exercise impacts heart rate variability but not cognitive flexibility during subsequent simulated firefighter occupational tasks.

Acute exercise can transiently enhance cognitive flexibility. The cognitive demand of firefighters makes it relevant to understand if on-shift exercise could produce similar improvements in cognitive performance during subsequent occupational tasks. Metrics of heart rate variability (HRV), such as time- and frequency-domain outcomes, may shed light upon the influence exercise has on cognition, as they discern information related to cardiac autonomic (sympathetic/parasympathetic) function. We aimed to determine if acute resistance and aerobic exercise impact cognitive flexibility during occupational tasks and its relation to HRV. 32 participants completed a baseline Wisconsin Card Sorting Task (WCST) and three experimental trials: resistance exercise (RE), aerobic exercise (AE), or a rested control (CON). An occupational task assessment (OTA) including four rounds of 10 deadlifts and a 0.15-mile sandbag carry in an environmental chamber (35°C/50% humidity) was completed after each trial. The second round was followed by the WCST. Repeated measures ANOVAs were used to analyze differences by condition. For the WCST, total, perseverative, and non-perseverative errors did not differ (ps > 0.39). Time-domain HRV metrics were not different (ps > 0.05). All frequency-domain metrics, other than low-frequency power, were not different (ps > 0.24). Low-frequency power was lower based on condition (p = 0.03). Post hoc analysis showed low-frequency power was lower following AE compared to RE and CON. Results suggest an acute bout of on-shift aerobic or resistance exercise may not impact cognitive flexibility during subsequent simulated occupational tasks, despite depressed metrics of heart rate variability following aerobic exercise.

Extracellular vesicle transfer of miR-1 to adipose tissue modifies lipolytic pathways following resistance exercise.

Extracellular vesicles (EVs) have emerged as important mediators of intertissue signaling and exercise adaptations. In this human study, we provide evidence that muscle-specific microRNA-1 (miR-1) was transferred to adipose tissue via EVs following an acute bout of resistance exercise. Using a multimodel machine learning automation tool, we discovered muscle primary miR-1 transcript and CD63+ EV count in circulation as top explanatory features for changes in adipose miR-1 levels in response to resistance exercise. RNA-Seq and in-silico prediction of miR-1 target genes identified caveolin 2 (CAV2) and tripartite motif containing 6 (TRIM6) as miR-1 target genes downregulated in the adipose tissue of a subset of participants with the highest increases in miR-1 levels following resistance exercise. Overexpression of miR-1 in differentiated human adipocyte-derived stem cells downregulated these miR-1 targets and enhanced catecholamine-induced lipolysis. These data identify a potential EV-mediated mechanism by which skeletal muscle communicates with adipose tissue and modulates lipolysis via miR-1.

Time Spent Near Maximal Oxygen Uptake During Exercise at Different Regions of the Severe-Intensity Domain.

Faricier, R, Fleitas-Paniagua, PR, Iannetta, D, Millet, GY, Keir, DA, and Murias, JM. Time spent near maximal oxygen uptake during exercise at different regions of the severe-intensity domain. J Strength Cond Res XX(X): 000-000, 2024-This study applied the critical power (CP) model and several bouts of constant-power exercise within different regions of the severe-intensity domain to determine whether there exists an optimal intensity to maximize time spent near V̇o2peak. Subjects visited the laboratory 9 times. After a ramp-incremental test to determine V̇o2peak and peak power output (POpeak), 9 active individuals (5 females) performed 4 constant-power bouts to task failure between 65 and 100%POpeak to estimate CP and total finite work above CP (W'). Subjects then completed 4 additional exhaustive trials predicted to result in task failure in ∼3, 6, 9, and 12 minutes. Time spent at V̇o2peak was calculated as the duration at which V̇o2 ≥ 95% of the trial-specific V̇o2peak. The level of significance set for the study was p < 0.05. Mean CP and W' were 201 ± 48 W and 17.6 ± 8.4 kJ, respectively. For each bout, time to task failure was 2.7 ± 0.5, 6.3 ± 0.6, 9.5 ± 1.2, and 13.1 ± 3.1 minutes for the 3-, 6-, 9-, and 12-minute conditions. Time spent at V̇o2peak during the 3-minute trial (45 ± 22 seconds) was shorter than during the 9-minute (204 ± 104 seconds; p = 0.002) and 12-minute trials (260 ± 155 seconds; p < 0.001). The 6-minute trial (117 ± 46 seconds) had shorter (p = 0.005) time spent at V̇o2peak compared with the 12-minute trial. At least when performing single bouts of exercise, intensities closer to CP (i.e., those sustainable for ∼9 minutes or longer) seem preferable compared with POs in the upper regions of the severe-intensity domain to maximize time at V̇o2peak.

Post-exercise hot-water immersion is not effective for ribosome biogenesis in rat skeletal muscle.

Ribosome biogenesis is an important regulator of skeletal muscle hypertrophy induced by repeated bouts of resistance exercise (RE). Hot-water immersion (HWI), a widely used post-exercise recovery strategy, activates the mechanistic target of rapamycin (mTOR) signaling, a key regulator of ribosome biogenesis in skeletal muscle. However, the effect of HWI on skeletal muscle ribosome biogenesis is not well understood. Here, we aimed to investigate the effects of HWI and post-exercise HWI on ribosome biogenesis using a rat RE model. Male Sprague-Dawley rats were randomly assigned to HWI and non-HWI groups. In both groups, the right leg was isometrically exercised using transcutaneous electrical stimulation, while the left leg was used as an internal non-RE control. Following RE, both limbs were immersed in hot water (41.2 ± 0.03℃) for 20 min under isoflurane anesthesia in the HWI group and the gastrocnemius muscles were sampled at 3 and 24 h post-exercise. HWI significantly increased mTOR signaling and c-Myc mRNA expression, whereas post-exercise HWI significantly increased transcription initiation factor-IA mRNA expression. However, neither HWI nor post-exercise HWI enhanced 45S pre-rRNA expression, ribosomal RNA, or ribosomal protein content. Additionally, HWI tended to decrease 28S rRNA and 18S rRNA content, widely used markers of ribosome content. These results suggest that HWI as a post-exercise recovery is not effective in activating ribosome biogenesis.

Effect of habitual physical activity on motor performance and prefrontal cortex activity during implicit motor learning.

Acute bouts of exercise have been shown to improve motor learning. However, whether these benefits can be observed from habitual physical activity (PA) levels remains unclear and has important implications around PA guidelines to promote motor learning across the lifespan. This study investigated the effect of habitual PA levels on brain activity within the dorsolateral prefrontal cortex (DLPFC) during procedural motor skill acquisition. Twenty-six right-handed healthy young adults had physical activity levels quantified by calculating the metabolic equivalent of task (METs) in minutes per week, derived from the International Physical Activity Questionnaire (IPAQ). Functional near-infrared spectroscopy (fNIRS) over the DLPFC was recorded to measure neural activation during a serial reaction time task (SRTT). Behavioural indicators of procedural motor skill acquisition were quantified as reaction time and accuracy of correct trials during the SRTT. DLPFC activation was characterised as task-related changes in oxyhaemoglobin (∆[HbO2]). Findings showed that higher PA levels were associated with improvements in reaction time during procedural motor skill acquisition (p = 0.03). However, no significant effects of PA levels on accuracy or ∆[HbO2] during procedural motor skill acquisition were observed. These findings show that while habitual PA may promote motor performance in young adults, this is not reflected by changes in the DLPFC area of the brain.

Physiological, Performance and Perceptual Effects of Acute Intake of an L-Arginine and L-Citrulline Beverage Prior to a Repeated Bout of Intensive Running Among University Soccer Players

The purpose of this study was to determine whether a combined L-arginine and L-citrulline beverage can enhance total nitric oxide (NOx), as well as physiological (cardiopulmonary metrics) and perceptual (rate of perceived exertion) responses to a repeated bout of high-intensity exercise among university soccer players. Thirty male soccer players were included in a randomized double-blind, placebo-controlled, parallel design. Participants performed two bouts of high-intensity running, spaced two hours apart. Forty minutes before the second bout only, participants consumed a 500 mL beverage containing 6 g L-arginine and 6 g L-citrulline (n = 15) or placebo (n = 15). Blood NOx concentration was measured immediately before and after both bouts. There was no significant increase in NOx or significant interaction effects for physiological, performance, or perceptual variables between the L-arginine/L-citrulline and placebo groups. The peak volume of oxygen uptake of the L-arginine/L-citrulline group was significantly higher in the second compared with the first exercise bout (54.92 ± 4.81 vs. 50.54 ± 9.22 mL/kg/min; p = 0.01). In the second bout of exercise, time to exhaustion in the L-arginine/L-citrulline group increased by 8.5% (~60 s) compared to the first. In conclusion, these results suggest that a single dose of L-arginine/L-citrulline beverage did not increase NOx yet seemed to impact aerobic metabolism in university soccer players.

Sex-based differences in the blood pressure responses to muscle metaboreflex activation are consistent between limb and respiratory muscle.

The purpose of this study was to compare sex-based differences in the mean arterial blood pressure (MAP) response to limb and inspiratory metaboreflex activation, during relative and absolute workloads. Healthy males (n = 9) and females (n = 8) completed pulmonary function testing, forearm volume and circumference measurements, and bouts of limb and inspiratory muscle exercise. The exercises performed included bouts of rhythmic handgrip exercise (RHG) and inspiratory pressure threshold loading (PTL) to task failure, performed in a randomized order and separated by 30 minutes of rest. Participants performed both RHG and PTL at predetermined relative (R) and absolute (A) workloads, while cardiopulmonary measurements were recorded continuously. A time-dependent rise in MAP was observed in all participants, regardless of sex, muscle, or workload (P < 0.001). MAP was greater in males than females during all exercise bouts regardless of muscle group or workload (P < 0.001). The change in MAP from baseline was also greater in males (R-RHG: Δ31 ± 12 mmHg; R-PTL: Δ31 ± 9; A-RHG: Δ35 ± 6; and A-PTL: Δ30 ± 7) than females (R-RHG: Δ21 ± 7 mmHg; R-PTL: Δ13 ± 7; A-RHG: Δ21 ± 7; and A-PTL: Δ14 ± 3) (P < 0.001). Results from this study show that when the forearm and diaphragm perform the same relative or absolute work, the blood pressure response is statistically similar, and both responses are greater in males than females. The findings from the present study suggest that the sex-based difference in the response to metaboreflex activation is similar between the limb and respiratory musculature.NEW & NOTEWORTHY With rhythmic handgrip exercise and inspiratory pressure threshold loading there was a time-dependent rise in the blood pressure that was significantly lower in females than males. The blunted blood pressure response in females was present whether handgrip or inspiratory workload was relative or absolute. An attenuated cardiovascular response to high levels of limb or respiratory muscle work may have implications for whole body exercise in health and disease.

Elevated Plasma IL-6 Coincides with Activation of STAT3 in PBMC After Acute Resistance Exercise.

Changes in plasma concentrations of anti-inflammatory cytokines, such as interleukin-6 (IL-6) and IL-10, after acute resistance exercise (RE) have been widely explored. Whether observed changes in plasma cytokine concentration correspond to the activation of anti-inflammatory signaling pathways in immune cells after acute RE is unknown. This study aimed to determine if changes in plasma cytokines after acute RE resulted in the activation of anti-inflammatory signaling pathways in peripheral blood mononuclear cells (PBMC). Healthy young males (N = 16; age = 23.5 ± 2.7 yr; BMI = 22.4 ± 1.7 kg·m-2) participated in a single session of whole-body RE (4 sets of 4 different exercises at 70% 1-repetition maximum with the last set to failure) and a sedentary control (CON) condition in a randomized crossover design. Blood samples were collected at several time points before and after the exercise bout. Higher plasma IL-6, IL-10, and IL-1 RA concentrations were observed after RE compared with CON. Phosphorylation of STAT3 and protein expression of SOCS3 in PBMC were increased in RE compared with CON. The elevation of plasma IL-6, but not IL-10, coincided with the activation of STAT3 signaling in PBMC. These results highlight a potential mechanism by which RE may exert anti-inflammatory actions in circulating immune cells.

The Effect of Multi-Ingredient Protein versus Collagen Supplementation on Satellite Cell Properties in Males and Females.

Skeletal muscle satellite cells (SC) contribute to the adaptive process of resistance exercise training (RET) and may be influenced by nutritional supplementation. However, little research exists on the impact of multi-ingredient supplementation on the SC response to RET. We tested the effect of a multi-ingredient supplement (MIS) including whey protein, creatine, leucine, calcium citrate, and vitamin D on SC content and activity as well as myonuclear accretion, SC and myonuclear domain compared with a collagen control (COL) throughout a 10-wk RET program. Twenty-six participants underwent a 10-wk linear RET program while consuming either the MIS or COL supplement twice daily. Muscle biopsies were taken from the vastus lateralis at baseline and 48 h after a bout of damaging exercise, before and after RET. Muscle tissue was analyzed for SC and myonuclear content, domain, acute SC activation, and fiber cross-sectional area (fCSA). MIS resulted in a greater increase in type II fCSA following 10 wk of RET (effect size (ES) = 0.89) but not myonuclear accretion or SC content. Change in myonuclei per fiber was positively correlated with type I and II and total fiber hypertrophy in the COL group only, indicating a robust independent effect of MIS on fCSA. Myonuclear domain increased similarly in both groups, whereas SC domain remained unchanged following RET. SC activation was similar between groups for all fiber types in the untrained state but showed a trend toward greater increases with MIS after RET (ES = 0.70). SC responses to acute damaging exercise and long-term RET are predominantly similar in MIS and COL groups. However, MIS can induce greater increases in type II fCSA with RET and potentially SC activation following damage in the trained state.

Movement boosts memory: Investigating the effects of acute exercise on episodic long-term memory

Long-term memory is important for cognitive health across the lifespan. Previously research has indicated that a bout of exercise improves memory retention for approximately one week; however, its prolonged effects are unknown. This study investigated the effects of acute moderate-intensity exercise on long-term memory for 11 months. Participants engaged in the exercise intervention and seated rest control condition, followed by a word encoding memory task. Word retention in the exercise intervention was better than in the control condition at 6- and 8-weeks post-encoding. These findings suggest that exercise before encoding enhances long-term episodic memory recall for at least eight weeks.

Skeletal muscle from TBC1D4 p.Arg684Ter variant carriers is severely insulin resistant but exhibits normal metabolic responses during exercise.

In the Greenlandic Inuit population, 4% are homozygous carriers of a genetic nonsense TBC1D4 p.Arg684Ter variant leading to loss of the muscle-specific isoform of TBC1D4 and an approximately tenfold increased risk of type 2 diabetes1. Here we show the metabolic consequences of this variant in four female and four male homozygous carriers and matched controls. An extended glucose tolerance test reveals prolonged hyperglycaemia followed by reactive hypoglycaemia in the carriers. Whole-body glucose disposal is impaired during euglycaemic-hyperinsulinaemic clamp conditions and associates with severe insulin resistance in skeletal muscle only. Notably, a marked reduction in muscle glucose transporter GLUT4 and associated proteins is observed. While metabolic regulation during exercise remains normal, the insulin-sensitizing effect of a single exercise bout is compromised. Thus, loss of the muscle-specific isoform of TBC1D4 causes severe skeletal muscle insulin resistance without baseline hyperinsulinaemia. However, physical activity can ameliorate this condition. These observations offer avenues for personalized interventions and targeted preventive strategies.

Benefits of a light- intensity bout of exercise on attentional networks functioning

The effects of physical exercise on attentional performance have received considerable interest in recent years. Most of previous studies that assessed the effect of an acute bout of exercise on attentional performance have generally been approached by analysing single attentional functions in isolation, thus ignoring the functioning of other attentional functions, which characterizes the real perception-action environmental conditions. Here, we investigated the effect of two different intensities (light vs. vigorous) of acute exercise on attentional performance by using the ANTI-Vea, a behavioral task that simultaneously measures three attentional functions (phasic alertness, orienting, and cognitive control) and the executive and arousal components of vigilance. 30 young (age = 20.93; SD = 1.51 years) physically active participants (21 men and 9 women) completed three experimental sessions: the first one to assess their physical fitness and baseline performance in the ANTI-Vea, and the other two sessions (in counterbalanced order) to assess changes in attentional and vigilance performance after an acute bout of light- intensity vs. vigorous- intensity physical exercise. Beneficial effects on some accuracy scores (i.e., overall higher accuracy in the attentional sub-task and fewer false alarms in the executive vigilance sub-task) were observed in the light- intensity exercise condition compared to baseline and vigorous- intensity. Additionally, the RT score of phasic alertness was increased after the light- intensity exercise in comparison with baseline. The present findings suggest that a bout of acute exercise at light- intensity might induce some short-term beneficial effects on some aspects of attention and vigilance.