Long-duration Exercise Research Articles

Impact of high intensity and long duration exercise in genetic arrhythmogenic left ventricular cardiomyopathy

Abstract Background Arrhythmogenic left ventricular (LV) cardiomyopathy (ALVC) is a genetic disease associating extensive LV myocardial fibrosis with or without dysfunction and no or mild right ventricle (RV) involvement, at risk of life-threatening ventricular arrhythmias (VA). While high intensity (HI) and long duration (LD) exercise has been identified as a precipitating factor of RV dysfunction and VA in arrhythmogenic RV cardiomyopathy including in asymptomatic genetic variant carriers, the impact of exercise on disease phenotype and risk is not known in ALVC. Objective To study the relationship between practicing HI and LD exercise and the risk of developing an ALVC phenotype and its severity. Methods In a monocentric retrospective observational study, patients with a pathogenic variant in common ALVC genes (DSP, FLNC, DES, PLN, RBM20, TMEM43), including asymptomatic carriers without ALVC phenotype, were interviewed about their physical practice from age 7 to the time of genetic or disease diagnosis. Intensity and weekly duration of each activity were reported. HI and LD exercise were defined as having practiced at least 1 sport with an intensity ≥ 6 METs and ≥ 2.5 hours/week respectively. We studied the association of HI and LD exercise practice with the risk of ALVC phenotype occurrence and its severity, derived from clinical, ECG and imaging data. Results 114 out of 128 eligible patients answered the questionnaire and were included (85 (74.6%) with a DSP variant, 22 FLNC (19.3%), 6 DES (5.3%), 1 RBM20 (0.9%)). 35 were probands (31%) and 79 relatives (69%) among 46 families. 31 (27%) had no ALVC phenotype at the time of genetic diagnosis. Mean age at diagnosis was 41±18. 62 (54%) patients were women. 97 (85%) had practiced at least one sport, among which 81 (83.5%) at HI and 79 (81.4%) of LD. Median lifetime exercise dose was 18.5 MET.h/week. There were no differences in HI and LD exercise practice between probands and relatives (74.3% vs 69.6%, p=0.6 and 74.3% vs 67.1%, p=0.4 respectively), as well as between patients with and patients without ALVC phenotype at the time of diagnosis (74.7% vs 61.3%, p=0.2 and 72.3% vs 61.3%, p=0.3 respectively). Phenotypic features at diagnosis did not differ between patients with and without HI and LD practice (Table 1). Multivariate analysis adjusted on age and gender showed that HI and LD exercise were not significantly associated with an increased risk of developing an ALVC phenotype (Odds Ratio [95% confidence interval] for age, gender, HI and LD exercise were 1.03 [1.01-1.06] (p=0.013), 1.41 [0.58 ; 3.47] (p=0.45), 2.15 [0.63 ; 7.27] (p=0.22) and 1.17 [0.35 ; 3.87] (p=0.79) respectively). Phenotypic features at diagnosis did not differ across observed quartiles of lifetime exercise dose (Table 2). Conclusion Practicing HI and LD exercise was not associated with an increased risk of developing an ALVC phenotype and its severity at the time of diagnosis in genetic ALVC variant carriers.

The impact of COVID-19 infection on musculoskeletal pain and its associating factors: a cross-sectional study.

Musculoskeletal pain after COVID-19 infection remains a concerning long-term complication of COVID-19. Here, our study aimed to investigate the prevalence of musculoskeletal pain associated with COVID-19 (MSPC) and healthcare-seeking behaviors, as well as the associating factors. A cross-sectional survey was conducted using convenience sampling and distributed to participants anonymously through the online platform Credamo. Demographic and characteristic data of the participants were collected and analyzed. Logistic regression analysis was employed to investigate potential factors associated with MSPC and healthcare-seeking tendencies. A total of 1,510 participants responded to the survey, with 42.6% (643 individuals) exhibiting MSPC. Higher education level and a greater number of concomitant symptoms were significant risk factors for MSPC, while longer exercise duration and higher PSS-10 scores were protective factors. Additionally, higher income level, frequency and severity of pain, and greater PSS-10 scores increased healthcare-seeking intention. A significant proportion of individuals experience MSPC. Education level and concomitant symptoms were risk factors for MSPC, while exercise duration and PSS-10 score were potential protective factors. Income level, frequency and severity of pain, and PSS-10 score are significantly related to the willingness to seek medical treatment for MSPC.

The kinetics of cardiac troponin T release during and after 1- and 6-h maximal cycling trials

ObjectivesIn this study, the effects of short-duration high-intensity exercise and long-duration exercise on high-sensitivity cardiac troponin T (hs-cTnT) levels were compared. MethodsTwelve male amateur cyclists performed 1- and 6-h cycling trials. In both exercise trials, hs-cTnT was assessed at rest, immediately postexercise and at 1, 3, 6, 12, and 24 h postexercise. Additionally, hs-cTnT levels were assessed every hour during the 6-h trial. ResultsExercise resulted in an increase in hs-cTnT levels in all subjects. Circulating hs-cTnT levels increased in both exercise trials (p < 0.001), with higher peak values occurring after the 1-h trial compared with those of the 6-h trial (p = 0.023). The upper reference limit (URL) exceeded 83 % of the participants in the 1-h trial and 42 % of the participants in the 6-h trial. There was substantial individual variability in peak hs-cTnT in both trials. Values of hs-cTnT were greater after exercise than during exercise for the 6-h trial. For both exercise trials, the maximum postexercise hs-cTnT values correlated with the %HRMAX (r = 0.906 for the 1-h trial, r = 0.735 for the 6-h trial). For the 1-h trial, the maximum postexercise hs-cTnT values were observed at 3 h in all subjects. No significant difference in the hs-cTnT values was observed for the 6-h trial during the first 12 h postexercise. ConclusionsOur results demonstrated greater hs-cTnT levels in young male participants after a 1-h cycling trial than after a 6-h cycling trial, despite a substantially greater energy expenditure and total external work completed in the 6-h trial. Postexercise hs-cTnT values are associated with relative exercise intensity.

Personality profiles and exercise behaviour across adulthood

AbstractPersonality has constituted a significant psychological component predicting physical exercise. Prior research mostly focused on how personality domains are associated with exercise behaviour. Yet, focusing more closely on combinations of personality domains may be valuable in the future. The present cross‐sectional study aimed to bridge this gap by investigating the associations between Big Five personality profiles and exercise behaviour based on a person‐centred approach in adults. Data from the China Family Panel Studies (CFPS) were used (N = 28,304), in which participants reported their Big Five personality and exercise behaviour. Latent profile analyses, grounded in young adulthood, middle adulthood, and later adulthood sub‐samples, identified five personality profiles: moderate, reserved, confident, resilient, and vulnerable. Across three age groups, significant differences between the five personality profiles in relation to exercise behaviour were revealed. Individuals with the resilient or confident profiles generally had longer exercise duration while people with the vulnerable profile tended to exercise less. Our findings give greater insight into the relationship between exercise and personality, suggesting that different combinations of personality traits may determine individuals' exercise behaviour. It opens promising avenues for identification of adults at risk of lacking exercise, and for development of personality‐targeted exercise interventions.

EXERCISE IN ADULTS WITH ATTENTION-DEFICIT/HYPERACTIVITY DISORDER: A SYSTEMATIC REVIEW

INTRODUCTION &amp; AIMS Attention-Deficit/Hyperactivity Disorder (ADHD) is one of the most common neurodevelopmental disorders in adults. Stimulant medications are first-line treatments, they have many side effects and do not address common comorbidities such as cardiometabolic disease, depression, and anxiety. Exercise, by contrast, not only improves ADHD symptoms in youth but effectively treats such comorbidities, making it a potentially valuable treatment option. However, exercise efficacy in adults with ADHD has not been systematically reviewed. Therefore, we aimed to summarise the results of acute exercise and training interventions on health-related outcomes for adults with ADHD, including ADHD symptoms, cognitive function, and psychological well-being. METHODS Using PRISMA guidelines, fifteen databases were searched (including grey literature) on 27/08/2020, yielding 22,088 unique publications. Database alerts were created to capture additional studies (n= 2). Screening, data extraction, Risk of Bias and GRADE assessment was conducted by CEHB. RESULTS Seven acute (6 cycling, 1 self-selected, 1 yoga) and 6 training studies (Yoga, Pilates, Kickboxing, Tai Chi, General Coordination, Group Circuit Class, Cycling) were included. Among acute studies, those reporting small-to-moderate improvements in cognitive function were characterised by longer duration exercise (&amp;gt;30 minutes), withholding ADHD medication before exercise, and using cohorts with clinician-confirmed ADHD diagnosis. Among the training studies, only one reported an improvement in cognition following Pilates when compared to an inactive control. It was longer (6 months vs. &amp;lt;8 weeks), prescribed progressive intensity and volume, and had high adherence compared to the non-significant trials. The certainty of evidence was low or very low for all outcomes. CONCLUSIONS Overall, acute exercise may have a small positive effect on cognition in adults with ADHD; however, certainty of the evidence is low. Further research is needed to investigate the impact of different modalities, durations, and intensities of acute exercise and chronic exercise on adult ADHD.

Increased risk of acute kidney injury in the first part of an ultra-trail-Implications for abandonment.

Acute kidneys injuries (AKIs) have been described in marathon and trail running. The currently available data allows assessment of before/after comparisons but does not allow an analysis of what happens during the race. A multidisciplinary assessment protocol was performed during the first trail of Clécy (Normandy France) in November 2021. This allowed an initial assay to be carried out, then at the end of each of the 6 loops of 26 km, and finally after 24 h of recovery. The race extends over 156 km in hilly terrain and 6000 m of elevation gain (D+). The level of impairment according to the RIFLE classification was defined for each runner at each assay. Fifty-five runners were at the start, and the per protocol analysis involved 36 runners (27 men and 9 women, 26 finishers). Fifteen (41.7%) of the riders presented at least one result corresponding to a "RIFLE risk" level. After 24 h of rest, only one runner still had a "RIFLE Risk". The distance around the marathon seems to be the moment of greatest risk. For the first time, we find an association between this renal risk and the probability of abandonment. Many runners are vulnerable to kidney damage during long-duration exercise, which is why it's important to limit risk situations, such as the use of potentially toxic drugs or hydration disorders. The consumption of NSAIDs (nonsteroidal anti-inflammatory drugs) before or during an ultra-distance race should therefore be prohibited. Attention should be paid to hydration disorders.

Physical Activity Components that Determine Daily Life Satisfaction Among Older Adults: An Intensive Longitudinal Diary Study.

Although previous studies have shown that engaging in physical activity can elevate daily life satisfaction, few studies have identified the specific aspects that can result in this. This study examined whether enjoying moderate-to-vigorous intensity exercises with others for a longer time, but not any aspects of non-exercise physical activity, was associated with higher daily life satisfaction among older adults. We conducted an intensive longitudinal diary survey of 182 individuals for 1week and obtained valid data for 853 person-days. The time spent engaging in light and moderate-to-vigorous physical activity at 8:00-11:59, 12:00-15:59, and 16:00-19:59h was measured using an accelerometer. Duration, intensity, timing, social context, and enjoyment of the exercises were assessed based on diary entries. Stratified by non-exercise and exercise days, we conducted multilevel models. On non-exercise days, longer duration of light physical activity from 12:00 to 15:59 at the within-person level was associated with higher daily life satisfaction. On exercise days, longer duration of moderate-to-vigorous physical activity from 12:00 to 15:59 at the within-person level, longer exercise duration at the within-person level, exercising with moderate-to-vigorous intensity, and enjoyment of exercise at both the within- and between-person levels were associated with higher daily life satisfaction. These findings indicate that enjoying moderate-to-vigorous intensity exercise for a longer duration than usual and engaging in non-exercise physical activity in the afternoon are important for elevating older adults' daily life satisfaction.

Four-compartment muscle fatigue model to predict metabolic inhibition and long-lasting nonmetabolic components.

Introduction: Computational muscle force models aim to mathematically represent the mechanics of movement and the factors influencing force generation. These tools allow the prediction of the nonlinear and task-related muscle behavior, aiding biomechanics, sports science, and rehabilitation. Despite often overlooking muscle fatigue in low-force scenarios, these simulations are crucial for high-intensity activities where fatigue and force loss play a significant role. Applications include functional electrical stimulation, motor control, and ergonomic considerations in diverse contexts, encompassing rehabilitation and the prevention of injuries in sports and workplaces. Methods: In this work, the authors enhance the pre-existing 3CCr muscle fatigue model by introducing an additional component of force decay associated with central fatigue and a long-term fatigue state. The innovative four-compartment model distinguishes between the short-term fatigued state (related to metabolic inhibition) and the long-term fatigued state (emulating central fatigue and potential microtraumas). Results: Its validation process involved experimental measurements during both short- and long-duration exercises, shedding light on the limitations of the traditional 3CCr in addressing dynamic force profiles.

Compositional Aspects of Beverages Designed to Promote Hydration Before, During, and After Exercise: Concepts Revisited.

Hypohydration can impair aerobic performance and deteriorate cognitive function during exercise. To minimize hypohydration, athletes are recommended to commence exercise at least euhydrated, ingest fluids containing sodium during long-duration and/or high-intensity exercise to prevent body mass loss over 2% and maintain elevated plasma osmolality, and rapidly restore and retain fluid and electrolyte homeostasis before a second exercise session. To achieve these goals, the compositions of the fluids consumed are key; however, it remains unclear what can be considered an optimal formulation for a hydration beverage in different settings. While carbohydrate-electrolyte solutions such as sports drinks have been extensively explored as a source of carbohydrates to meet fuel demands during intense and long-duration exercise, these formulas might not be ideal in situations where fluid and electrolyte balance is impaired, such as practicing exercise in the heat. Alternately, hypotonic compositions consisting of moderate to high levels of electrolytes (i.e., ≥45 mmol/L), mainly sodium, combined with low amounts of carbohydrates (i.e., <6%) might be useful to accelerate intestinal water absorption, maintain plasma volume and osmolality during exercise, and improve fluid retention during recovery. Future studies should compare hypotonic formulas and sports drinks in different exercise settings, evaluating different levels of sodium and/or other electrolytes, blends of carbohydrates, and novel ingredients for addressing hydration and rehydration before, during, and after exercise.

Effect of exercise training on functional capacity, muscle strength, exercise capacity, dialysis efficacy and quality of life in children and adolescents with chronic kidney disease: a systematic review and meta-analysis.

To synthesize the effect of exercise training on functional capacity, muscle strength, exercise capacity, dialysis efficacy, and quality of life (QOL) in children and adolescents with CKD. PubMed/Medline, Scopus, PEDro, Web of Science, CINAHL, Cochrane, and Embase were searched from inception to September 30, 2023. Randomized control trials (RCTs) and clinical trials that assessed the effect of exercise training programs on functional capacity, muscle strength, exercise capacity, dialysis efficacy, and QOL in children and adolescents with CKD were included. Random effect model and meta-regression were used for the meta-analysis. Four clinical trials and three RCTs were included. The results showed that exercise training improves strength, but meta-analysis did not show a significant effect of exercise on functional capacity (WMD: 1.02; 95% CI: - 0.14 to 2.18; p = 0.083) and QOL (WMD: 8.00; 95% CI: - 3.90 to 19.91; p = 0.187). Subgroup analysis revealed that more than 25 sessions and 45min per session of intervention, a PEDro score of more than 5, and being younger than 12years of age had a large effect on functional capacity and QOL results. Due to the limited number of studies that reported the effect of exercise on dialysis efficacy and exercise capacity, the findings were inconclusive. Exercise training could benefit children and adolescents with CKD by increasing their strength. Longer exercise interventions may be beneficial for improving functional capacity and QOL. Future well-designed RCTs should overcome the existing limitations using adequate sample sizes and longer exercise durations.

Impact of Acute Exercise Challenge on Airway Dynamics in Children and Young Adults with Sickle Cell Anemia

Background Sickle cell anemia (SCA) complications such as frequent pain, chronic anemia, and acute and chronic organ damage lead to reduced physical functioning and cardiopulmonary fitness in affected individuals. Limited data support the safety of maximal cardiopulmonary exercise testing (CPET) in SCA, yet the safety of submaximal, longer-duration exercise at moderate to high intensity in SCA is unclear. The Sickle Cell Pro-Inflammatory Response to Interval Testing Study (SPRINTS) was a multicenter, prospective study that evaluated the impact of longer, submaximal exercise, which mimics the physical activity patterns of children better than CPET, on the acute inflammatory response and airway dynamics in children and young adults with SCA. In this analysis, we defined the effect of moderate to vigorous exercise on forced expiratory volume in 1 second (FEV1) and acute bronchoconstriction. We hypothesized the risk of exercise-induced bronchoconstriction (EIB) in children with SCA is greater than in controls. Methods SPRINTS was approved by the Lurie Children's central Institutional Review Board. Subjects 10-21 years old with hemoglobin (Hb) SS or S/β0 thalassemia and race-matched controls without SCA or sickle cell trait were enrolled across 4 institutions. Subjects were excluded for 1) inability to perform exercise, 2) receiving chronic transfusions, 3) history of exercise-related arrhythmia/syncope, 4) physician-diagnosed asthma, 5) history of EIB, or 6) history of cardiac disease precluding exercise testing. Participants performed maximal CPET on a cycle ergometer using a standardized Godfrey protocol. At least 2 weeks later, participants performed a controlled intensity interval test (CIIT) consisting of 8 bouts of constant workload cycling randomized to either 50% (moderate intensity) or 70% (vigorous intensity) of peak workload achieved during CPET. Exercise bouts were 2 min each with 1-min rest intervals between bouts. Spirometry was performed pre/post (5, 10, 15, and 30 min) CPET and CIIT. EIB was defined as a drop in FEV1 ≥10% from baseline to the lowest FEV1 recorded. Bivariable comparisons were performed, and logistic regression models analyzed the association between EIB and covariables (age, sex, SCA status, max workload, exercise intensity (CIIT only), baseline FEV1 % predicted, FEV1/FVC % predicted) using IBM ® SPSS ® Statistics. Results Available data from 64 subjects (48% F, 73% on hydroxyurea, mean 13.8±2.8 years) and 40 controls (45% F, mean 15.4±2.9 years) were analyzed. Baseline Hb (8.5±1.2 vs. 13±1.4 g/dL, p &amp;lt; 0.001) and maximal workload achieved during CPET (85±26 vs. 135±45 watts, p &amp;lt; 0.001) were lower in subjects vs. controls. The percentage of participants who completed CIIT did not differ between subjects and controls, and no respiratory-related adverse events, including need for bronchodilator therapy, occurred. At baseline, FEV1 and FEV1 % predicted and other parameters (FVC and FVC % predicted, MMEF and MMEF % predicted) were significantly lower in subjects vs. controls (Table 1). However, there was no between-group difference in baseline FEV1/FVC % predicted. Post-exercise, the percentage of participants who met criteria for EIB did not differ between subjects and controls after CPET (21 vs. 26%, p = 0.537) or CIIT (32 vs. 17%, p = 0.126). There was also no significant between-group difference in the greatest drop in FEV1 from baseline to any post-exercise timepoint (mean value or as % of baseline) after CPET or CIIT. In logistic regression models, SCA status, age, sex, maximal workload during CPET, exercise intensity (CIIT only), baseline FEV1 % predicted and FEV1/FVC % predicted were not associated with EIB after CPET or CIIT (Table 2). Conclusion Compared to controls, children and young adults with SCA and no history of asthma or EIB had lower baseline values on all spirometry parameters except FEV1/FVC % predicted. EIB was not more common in subjects with SCA vs. controls after maximal CPET or a submaximal exercise challenge of longer duration at moderate or vigorous intensity. No independent factors were associated with development of EIB after acute exercise. Despite concerns that undiagnosed lower airways disease in children with SCA is common, our results suggest the risk of EIB in SCA is low and underscore the safety of moderate to vigorous exercise toward developing evidence-based exercise guidelines in non-asthmatic children and young adults with SCA.

Effect of non-pharmacological interventions on the prevention of sarcopenia in menopausal women: a systematic review and meta-analysis of randomized controlled trials

BackgroundSarcopenia is a chronic disease marked by gradual muscle system and functional decline. Prior research indicates its prevalence in those under 60 varies from 8 to 36%. There is limited evidence on the effectiveness of non-pharmacological interventions for sarcopenia prevention in menopausal women aged 40–60. This study examines the influence of such interventions for sarcopenia prevention on these women.MethodsPubMed, EMBASE, Medline, Cochrane Library, CINAHL, PEDro, and Airiti Library were searched from inception until May 5, 2023. Randomized controlled trials that examined exercise, vitamin D and protein supplementation effects on muscle mass, strength, and physical function. Quality assessment used the Cochrane risk of bias tool, and analysis employed Comprehensive Meta-Analysis version 2.0.ResultsA total of 27 randomized controlled trials, involving 1,989 participants were identified. Meta-analysis results showed exercise improved lean body mass (SMD = 0.232, 95% CI: 0.097, 0.366), handgrip strength (SMD = 0.901, 95% CI: 0.362, 1.441), knee extension strength (SMD = 0.698, 95% CI: 0.384, 1.013). Resistance training had a small effect on lean body mass, longer exercise duration (> 12 weeks) and higher frequency (60–90 min, 3 sessions/week) showed small to moderate effects on lean body mass. Vitamin D supplementation improved handgrip strength (SMD = 0.303, 95% CI: 0.130, 0.476), but not knee extension strength. There was insufficient data to assess the impact of protein supplementation on muscle strength.ConclusionsExercise effectively improves muscle mass, and strength in menopausal women. Resistance training with 3 sessions per week, lasting 20–90 min for at least 6 weeks, is most effective. Vitamin D supplementation enhances small muscle group strength. Further trials are needed to assess the effects of vitamin D and protein supplementation on sarcopenia prevention.Registration numberThis review was registered on PROSPERO CRD42022329273.

Mouse skeletal muscle adaptations to different durations of treadmill exercise after the cessation of FOLFOX chemotherapy.

FOLFOX (5-fluorouracil, leucovorin, oxaliplatin) chemotherapy is a treatment for colorectal cancer that can induce persistent fatigue and metabolic dysfunction. Regular exercise after chemotherapy cessation is widely recommended for cancer patients and has been shown to improve fatigue resistance in mice. However, gaps remain in understanding whether the early systemic and skeletal muscle adaptations to regular exercise are altered by prior FOLFOX chemotherapy treatment. Furthermore, the effects of exercise duration on early metabolic and skeletal muscle transcriptional adaptations are not fully established. Purpose: Investigate the effects of prior FOLFOX chemotherapy treatment on the early adaptations to repeated short- or long-duration treadmill exercise, including the fasting regulation of circulating metabolic regulators, skeletal muscle COXIV activity and myokine/exerkine gene expression in male mice. Methods: Male C57BL6/J mice completed 4 cycles of FOLFOX or PBS and were allowed to recover for 4-weeks. Subsets of mice performed 14 sessions (6d/wk, 18m/min, 5% grade) of short- (10min/d) or long-duration (55min/d) treadmill exercise. Blood plasma and muscle tissues were collected 48-72h after the last exercise bout for biochemical analyses. Results: Long-duration exercise increased fasting plasma osteocalcin, LIF, and IL-6 in healthy PBS mice, and these changes were ablated by prior FOLFOX treatment. Slow-oxidative soleus muscle COXIV activity increased in response to long-duration exercise in PBS mice, which was blocked by prior FOLFOX treatment. Fast-glycolytic plantaris muscle COXIV activity increased with short-duration exercise independent of FOLFOX administration. There was a main effect for long-duration exercise to increase fasting muscle IL-6 and COXIV mRNA expression independent of FOLFOX. FOLFOX administration reduced muscle IL-6, LIF, and BDNF mRNA expression irrespective of long-duration exercise. Interestingly, short-duration exercise suppressed the FOLXOX induction of muscle myostatin mRNA expression. Conclusion: FOLFOX attenuated early exercise adaptations related to fasting circulating osteocalcin, LIF, and IL-6. However, prior FOLFOX treatment did not alter the exercise adaptations of plantaris muscle COXIV activity and plasma adiponectin. An improved understanding of mechanisms underlying exercise adaptations after chemotherapy will provide the basis for successfully treating fatigue and metabolic dysfunction in cancer survivors.

A narrative review of exercise dose during pregnancy.

The current recommendations for prenatal exercise dose align with those from the American College of Sports Medicine; 150 min of moderate intensity every week of pregnancy. However, recent works suggest there may be a dose-dependent beneficial effect for mother and offspring; maternal and offspring health outcomes respond differently to low, medium, and high doses of prenatal exercise. It is, therefore, our aim to summarize the published evidence (years 1950-2023) for five metrics of prenatal exercise training commonly reported, that is, "FITT-V": Frequency (number of sessions), Intensity (metabolic equivalents "METs"), Time (duration of sessions), Type (exercise mode), Volume (exercise MET*mins). The target audience includes clinicians and health care professionals, as well as exercise professionals and physiologists. Data suggest that moderate exercise frequency (3-4 times weekly) appears safe and efficacious for mother and offspring, while there is contradictory evidence for the safety and further benefit of increased frequency beyond 5 sessions per week. Moderate (3-6 METs) and vigorous (>6 METs) intensity prenatal exercise have been shown to promote maternal and offspring health, while little research has been performed on low-intensity (<3 METs) exercise. Exercise sessions lasting less than 1 hr are safe for mother and fetus, while longer-duration exercise should be carefully considered and monitored. Taken together, aerobic, resistance, or a combination of exercise types is well tolerated at medium-to-high volumes and offers a variety of type-specific benefits. Still, research is needed to define (1) the "minimum" effective dose of exercise for mother and offspring health, as well as (2) the maximum tolerable dose from which more benefits may be seen. Additionally, there is a lack of randomized controlled trials addressing exercise doses during the three trimesters of pregnancy. Further, the protocols adopted in research studies should be more standardized and tested for efficacy in different populations of gravid women.

A 0.1% L-Menthol Mouth Swill in Elite Male Rugby Players Has Different Effects in Forwards and Backs.

Menthol mouth swills can improve endurance performance in the heat, which is attributed to attenuations in nonthermally derived thermal sensation (TS) and perception of effort. However, research in elite team-sport athletes is absent. Therefore, this study investigated the performance and TS responses to a 0.1% menthol mouth rinse (MR) or placebo (PLA) among elite male rugby union players. Twenty-seven (15 Forwards and 12 Backs) elite male Super Rugby players completed two 3-minute 15-a-side rugby-specific conditioning blocks, with MR or PLA provided at the start of training (baseline), at the start of each 3-minute block (swill 1 [S1] and swill 2 [S2]), and at the end of training (swill 3 [S3]). TS was assessed using the American Society of Heating, Refrigerating and Air-Conditioning Engineers 9-point Analog Sensation Scale after each swill and at baseline (preconditioning block). Acceptability was measured after baseline swill and S3 using a 5-question Likert scale. Physical performance was measured throughout training using global positioning system metrics. MR attenuated TS from baseline to S1 (P = .003, SD = 1.01) and S2 (P = .002, SD = 1.09) in Forwards only, compared with PLA. Acceptability was higher only for Forwards in MR versus PLA at baseline (P = .003, SD = 1.3) and S3 (P = .004, SD = 0.75). MR had no effect on physical performance metrics (P > .05). MR attenuated the rise in TS with higher acceptability at S1 and S3 (in Forwards only) with no effect on selected physical performance metrics. Longer-duration exercise (eg,a match) in hot-humid conditions eliciting markedly increased body temperatures could theoretically allow favorable changes in TS to enhance performance-these postulations warrant experimental investigation.

Effect of an acute long-duration exercise bout on skeletal muscle lipid droplet morphology, GLUT 4 protein, and perilipin protein expression.

Smaller lipid droplet morphology and GLUT 4 protein expression have been associated with greater muscle oxidative capacity and glucose uptake, respectively. The main purpose of this study was to determine the effect of an acute long-duration exercise bout on skeletal muscle lipid droplet morphology, GLUT4, perilipin 3, and perilipin 5 expressions. Twenty healthy men (age 24.0 ± 1.0 years, BMI 23.6 ± 0.4 kg/m2) were recruited for the study. The participants were subjected to an acute bout of exercise on a cycle ergometer at 50% VO2max until they reached a total energy expenditure of 650kcal. The study was conducted after an overnight fast. Vastus lateralis muscle biopsies were obtained before and immediately after exercise for immunohistochemical analysis to determine lipid, perilipin 3, perilipin 5, and GLUT4 protein contents while GLUT 4 mRNA was quantified using RT-qPCR. Lipid droplet size decreased whereas total intramyocellular lipid content tended to reduce (p=0.07) after an acute bout of endurance exercise. The density of smaller lipid droplets in the peripheral sarcoplasmic region significantly increased (0.584 ± 0.04 to 0.638 ± 0.08 AU; p=0.01) while larger lipid droplets significantly decreased (p<0.05). GLUT4 mRNA tended to increase (p=0.05). There were no significant changes in GLUT 4, perilipin 3, and perilipin 5 protein levels. The study demonstrates that exercise may impact metabolism by enhancing the quantity of smaller lipid droplets over larger lipid droplets.

Effects of High-Intensity Interval Training on Melatonin Function and Cellular Lymphocyte Apoptosis in Sedentary Middle-Aged Men.

Background: Physical performance increased by controlled interventions of high-intensity intermittent training (HIIT); however, little is known about their influence as anti-aging and antioxidant effects, or their role in mitochondrial biogenesis. Purpose: This study aimed to determine the effects of HIIT for 12 weeks on melatonin function, lymphocyte cell apoptosis, oxidative stress on aging, and physical performance. Methods: Eighty healthy male subjects aged 18-65 years randomly participated in a HIIT-exercise training program for 12 weeks. Anthropometric analysis, cardiovascular fitness, total antioxidant capacity (TAC), lymphocyte count and apoptosis, and serum melatonin and cytochrome c oxidase (COX), were estimated for all subjects before and after HIIT-exercise training. HIIT training was performed in subjects for 12 weeks. Results: Data analysis showed a significant increase in the expression levels of the melatonin hormone (11.2 ± 2.3, p < 0.001), TAC (48.7 ± 7.1, p < 0.002), COX (3.7 ± 0.75, p < 0.001), and a higher percentage of lymphocyte apoptosis (5.2 ± 0.31, p < 0.003). In addition, there was an improvement in fitness scores (W; 196.5 ± 4.6, VO2max; 58.9 ± 2.5, p < 0.001), adiposity markers (p < 0.001); BMI, WHtR, and glycemic control parameters (p < 0.01); FG, HbA1c (%), FI, and serum C-peptide were significantly improved following HIIT intervention. Both melatonin and lymphocyte apoptosis significantly correlated with the studied parameters, especially TAC and COX. Furthermore, the correlation of lymphocyte apoptosis with longer exercise duration was significantly associated with increased serum melatonin following exercise training. This association supports the mechanistic role of melatonin in promoting lymphocyte apoptosis either via the extrinsic mediator pathway or via inhibition of lymphocyte division in the thymus and lymph nodes. Additionally, the correlation between melatonin, lymphocyte apoptosis, TAC, and COX activities significantly supports their role in enhancing physical performance. Conclusions: The main findings of this study were that HIIT exercise training for 12 weeks significantly improved adiposity markers, glycemic control parameters, and physical performance of sedentary older adult men. In addition, melatonin secretion, % of lymphocyte apoptosis, COX activities, and TAC as biological aging markers were significantly increased following HIIT exercise training interventions for 12 weeks. The use of HIIT exercise was effective in improving biological aging, which is adequate for supporting chronological age, especially regarding aging problems. However, subsequent studies are required with long-term follow-up to consider HIIT as a modulator for several cardiometabolic health problems in older individuals with obesity.

Assessment of Self-Determined Motivation in Exercise: A Systematic Review and Meta-analysis

systematic review and meta-analysis to assess associations between types of self-determined motivation in exercise with selected parameters of studies using Behavioral Regulation in Exercise Questionnaires (BREQs). Following PRISMA 2020 guidelines, we screened 244 studies from PubMed, ScienceDirect, and Scopus against criteria and selected 43 articles for qualitative synthesis. Of those, 40 studies reporting mean scores and standard deviations of six regulations of BREQs, representing self-determined motivation types, were selected for meta-analysis. The pooled mean scores were the highest in intrinsic regulation at 4.00 (95%CI: 2.92–5.09), followed by identified, integrated, introjected, external, and motivation regulations at 3.65 (95%CI: 3.06–4.24), 3.11 (95%CI: 2.68–3.55), 2.21 (95%CI: 1.88–2.53), 1.42 (95%CI: 0.93–1.92), and 0.94 (95%CI: 0.67–1.12), respectively. Findings indicated significant associations between longer exercise duration and introjected (β = 0.014, p = 0.027) and identified (β = 0.014, p = 0.021) regulations. An inverse relationship was found with a higher female participation rate (β=-0.047, p=0.042), while exercise settings in sports and fitness centers exhibited a stronger association with intrinsic motivations (β=2.700, p=0.039). No significant differences were observed among the versions of BREQs in measuring self-determined motivation. This investigation of context invariance utilizing the particular validated scale contributes to furthering comprehension of the instrument in sports and fitness settings. Additionally, it is essential to take into account sex and the exercise environment concerning self-determined motivation when predicting long-term exercise adherence. Doi: 10.28991/HEF-2023-04-02-08 Full Text: PDF

Caffeine Augments the Lactate and Interleukin-6 Response to Moderate-Intensity Exercise.

The release of interleukin (IL)-6 from contracting skeletal muscle is thought to contribute to some of the health benefits bestowed by exercise. This IL-6 response seems proportional to exercise volume and to lactate production. Unfortunately, high volumes of exercise are not feasible for all people. Caffeine augments the magnitude of increase in circulating IL-6 in response to high-intensity and long-duration exercise. Caffeine also increases circulating concentrations of lactate during exercise. We hypothesized that caffeine, ingested before short-duration, moderate-intensity exercise, would lead to greater circulating concentrations of lactate and IL-6 in a study population comprising both male and female individuals. Twenty healthy adults (10 men and 10 women age 25 ± 7 yr (mean ± SD)) completed 30 min of moderate-intensity cycle ergometer exercise, at an intensity corresponding to 60% peak oxygen uptake, after ingesting either caffeine (6 mg·kg -1 ) or placebo. Arterialized-venous blood was collected throughout each of the exercise sessions. Compared with placebo, caffeine increased circulating concentrations of lactate at the end of exercise (5.12 ± 3.67 vs 6.45 ± 4.40 mmol·L -1 , P < 0.001) and after 30 min of inactive recovery (1.83 ± 1.59 vs 2.32 ± 2.09 mmol·L -1 , P = 0.006). Circulating IL-6 concentrations were greatest after 30 min of inactive recovery ( P < 0.001) and higher with caffeine (2.88 ± 2.05 vs 4.18 ± 2.97, pg·mL -1 , P < 0.001). Secondary analysis indicated sex differences; caffeine increased the IL-6 response to exercise in men ( P = 0.035) but not in women ( P = 0.358). In response to moderate-intensity exercise, caffeine evoked greater circulating lactate concentrations in men and women but only increased the IL-6 response to exercise in men. These novel findings suggest that for men unwilling or unable to perform high-intensity and/or long-duration exercise, caffeine may augment the health benefits of relatively short, moderate-intensity exercise.

Low-load resistance exercise completed to volitional failure decreases pain perception post-exercise in females and males

Exercise-induced hypoalgesia (EIH) is the acute pain reduction post-exercise. Typically, high-intensity and/or long-duration exercise is required to elicit EIH. Alternatively, low-load resistance exercise with blood flow restriction (LL+BFR) may elicit EIH. However, there is conflicting evidence regarding the necessary repetitions and volume load. This study evaluated EIH after 75-repetitions (1×30, 3×15) (BFR-75) and four sets to volitional failure (BFR-F) protocols. Twenty-six participants completed unilateral knee extensions at 30% of maximal strength using a BFR-75 and BFR-F protocol. Pain pressure threshold (PPT) of the rectus femoris was assessed before and after exercise. Repetitions completed, volume load, occlusion time, and PPT were analyzed. Participants completed more repetitions (91.4±30.5), volume load (5,204.9±2,367.0 Nm), and had a longer occlusion time (345.8±76.2 seconds) during BFR-F compared to BFR-75 (73.2±3.7 repetitions, 4,451.1±1,498.1 Nm, 300.5±52.2 seconds, respectively). Collapsed across sex, PPT increased from pre- (3.24±1.91 kgf) to post-exercise (3.76±2.27 kgf) for BFR-F but not BFR-75 (3.51±1.67 to 3.68±2.04 kgf). The results indicated that BFR-F, but not BFR-75, elicited EIH, as assessed by an increase in PPT. Lower loads used during LL+BFR may be a clinically relevant alternative to high-intensity and/or long-duration exercise in populations that may not tolerate high-intensity or prolonged exercise to induce EIH.