High-Intensity Interval Training (HIIT) has gained prominence as a time-efficient and effective exercise modality to improve cardiovascular (CV) fitness, metabolic health, and physical performance. Therefore, our aim was to synthesize current clinical research on the effects of HIIT on the Autonomic Nervous System. We conducted the search for studies in the Directory of Open Access Journals, Embase, Virtual Health Library, Pubmed, and Scielo databases, in January of 2024. We included a total of 20 studies in our review. This literature review highlights the potential of HIIT to modulate the Autonomic Nervous System, enhancing CV function and overall health. Despite the promising findings, the interpretation of the results is tempered by the variability in study designs, populations, and methodologies. Future research should address these limitations, aiming for a more nuanced understanding of the relationship between HIIT and Autonomic Nervous System function. The review indicates that standardized protocols need to consider individual characteristics and baseline autonomic states for clinical application. As the body of evidence grows, HIIT may emerge as a cornerstone of exercise prescriptions aimed at optimizing autonomic function and promoting CV health.
Impairments on body function, activities of daily living (ADL) and cognition are common after stroke. Eccentric resistance training (ERT) may be implemented to improve them. The primary objectives were to evaluate whether ERT improves body function, ADL and cognition after stroke. The secondary objectives were to evaluate whether ERT improves strength, gait, quality of life, and self-perceived health.Seven electronic databases were searched: Cochrane Central Register of Controlled Trials, Cochrane Stroke Group Trials Register, PubMed, Epistemonikos, Embase, SPORTDiscus, and WHO International Clinical Trials Registry Platform. Last search was run in December 2023, including studies since 2012. Selection criteria were studies with stroke participants of both sexes, aged 18 or more, with an intervention based on ERT. Accepted languages were English, Spanish or French.First search was done in pairs. Authors removed duplicate studies and those which did not meet inclusion criteria through title and abstracts. Finally, all authors, independently, screened the final search results and extracted data.Of 68 records identified, 15 were eligible and 6 were finally included (with moderate risk of bias), analyzing 159 participants. Body function (4 interventions, n = 84), gait (4 interventions, n = 115) and strength (3 interventions, n = 78) showed significantly better results when ERT was performed. Meta-analysis could not be done because of the few studies and their heterogeneity.This review provided low-moderate quality evidence suggesting that ERT might be effective at improving body function, strength, and gait after stroke. Besides, no harm was documented, and it was well-accepted.
Constipation is correlated with diminished cognitive function, revealing a possible rectum-brain connection. In this counter-balanced crossover trial, 13 elite triathletes underwent a Stroop test to assess cognitive function and executive control. The Stroop test was conducted both with and without magnesium oxide intake, with a 1-week washout period between sessions. Oxygenation and blood distribution during the cognitive challenge were measured using Near-Infrared Spectroscopy (NIRS). Measurements were taken in both the prefrontal brain and the sub-navel region, where the highest glucose uptake was detected under the 18F-fluorodeoxyglucose Positron Emission Tomography (PET) scan. A significant reduction in completion time for the Stroop test was observed after defecation compared to the non-defecated condition (non-defecation: [27.1 ± 1.1] s; non-magnesium defecation: [24.4 ± 0.9] s; magnesium defecation: [23.4 ± 0.8] s, p < 0.05). Stroop test performance was improved in all (100%, 13/13) of the participants after magnesium-induced defecation and most (69%, 9/13) of the participants after non-magnesium-induced defecation. While no alterations in oxygenation and blood distribution were observed in the prefrontal brain during the Stroop test, decreased oxygenation levels were observed in the sub-navel region under both defecated conditions, without significant changes in blood distribution (p < 0.05). This data suggests an acute increase in oxygen consumption at this specific region. The result of this study suggests an unexplored causal link between the state of the rectum and cognitive performance. Magnesium supplementation to improved rectal emptying presents a novel application for optimizing cognitive function in athletes navigating intricate racing conditions.
This study aimed (1) to describe the experience of adolescents and adults using FitSpirit asynchronous virtual (V) exercise videos that target adolescent girls, (2) to compare physical activity (PA) levels and exercise-related self-perception variables among groups (2019 in-person [IP], 2021 IP, and 2021 V) of adolescent girls, and (3) to assess the association between the adolescents’ PA levels and their exercise-related self-perception in response to IP (pre-pandemic and during pandemic) and V (during pandemic) FitSpirit exercise modes. Regarding the first aim, 28 adolescent girls ([15.5 ± 0.8] years old) and 29 adult women ([33.0 ± 10.3] years old) experienced the V exercise mode. For the second and third aims, 376 girls ([15.3 ± 1.7] years old) participated IP in 2019 (pre-pandemic), 339 girls ([14.9 ± 1.6] years old) participated IP in 2021 (during the pandemic), and 27 girls ([15.5 ± 0.8] years old) watched V FitSpirit exercise videos in 2021 (during the pandemic). Data was collected using online questionnaires. Chi-square (χ2) and Pearson tests were performed. Adults (76%) had a significantly higher intention to use FitSpirit exercise videos again than adolescents (14%) (p < 0.001). For IP exercise mode, we observed significant correlations between PA levels and being proud (r = 0.08, p = 0.046), feeling good (r = 0.14, p < 0.001), and being disappointed (r = −0.12, p < 0.001). For the V exercise mode, there were no significant correlations. In conclusion, better exercise-related self-perception was only correlated to PA levels when IP training was offered. These first findings support IP training for adolescent girls when the pandemic situation allows it.
The present investigation examined the influence of age and pubertal transition on magnitude of muscle damage and inflammatory response following high intensity incremental treadmill running till volitional exhaustion in sixty-four sedentary prepubertal (n = 32) and postpubertal (n = 32) boys who were randomly recruited in the study. Muscle damage and inflammatory markers like creatine kinase (CK), lactate dehydrogenase (LDH), alanine aminotransferase (ALT), aspartate aminotranferase (AST), C-Reactive Protein (CRP) and Interleukin-6 (IL-6) were estimated before and after exercise. Serum CK, LDH, AST, ALT, CRP and IL-6 levels significantly increased after exercise in both the groups in comparison to respective pre-exercise values. Although CK, LDH, CRP and IL-6 responses were significantly higher in postpubertal boys, no intergroup variation was noted in post-exercise ALT activity. Age and body mass index (BMI) had significant positive correlation with post-exercise CK, LDH, AST, CRP, and IL-6 levels. Muscle injury and inflammation were significantly higher in postpubertal boys, suggesting a rise in these responses as a function of age and muscle mass during onset of puberty. Post-exercise release pattern of ALT was not influenced by age and puberty. Data also revealed that concentric endurance exercise did not induce extensive muscle damage and inflammation in both the groups. Drastic elevation in IL-6 level despite lower muscle damage implied that this marker was released from contracting muscle fibers independent of muscle damage and acute inflammation. The magnitude of this post-exercise IL-6 release increased as a function of age and BMI.
This study examined the repeated bout effect (RBE) on muscle damage markers following two bouts of neuromuscular electrical stimulation (NMES) in untrained individuals. Following familiarization, participants received 45 consecutive NMES to the biceps brachii at an intensity that produced low evoked force for the elbow flexors. Muscle damage markers (maximal voluntary isometric contraction [MVIC], elbow range of motion [ROM], muscle soreness via visual analogue scale [VAS] scores, pressure pain threshold [PPT], and muscle thickness) were measured before (PRE), after (POST), 1 day after (24 POST), and 2 days after (48 POST) NMES. Following 1 week of rest, procedures were replicated. Separate repeated measures two-way ANOVAs examined each measure. There were no interactions or bout main effects for MVIC or ROM. Time main effects indicated PRE MVIC was greater than POST (p = 0.002) and 24-POST (p = 0.024), and PRE ROM was greater than POST (p = 0.036). There was no interaction for muscle thickness. Respective time and bout main effects indicated muscle thickness at PRE was less than POST (p = 0.017), and second-bout muscle thickness (p = 0.050) was less compared to the initial-bout. For PPT, there was an interaction (p = 0.019). Initial-bout PRE PPT was less than POST (p = 0.033). Initial-bout 48-POST PPT was less than second-bout 48-POST (p = 0.037). There was a significant interaction for VAS (p = 0.009). Initial-bout PRE VAS was less than POST (p = 0.033) and 24-POST (p = 0.015). Initial-bout POST and 24-POST VAS were greater than second-bout POST (p = 0.023) and 24-POST (p = 0.006), respectively. The results support RBE on muscle damage markers related to inflammation, but not MVIC and ROM.
Marching band (MB) artists are often part of the general student population and not required to complete a pre-participation health screening to identify predisposing medical conditions or risks for injury/illness. Anecdotally, exertional heat illnesses (EHI) are a concern for MB artists. As more athletic trainers provide MB healthcare, research is needed on EHI occurrence and MB associated EHI risk factors. We utilized an exploratory cross-sectional study design to determine EHI risk factors, including previous EHI occurrence, among collegiate MB artists. MB artists (n = 1 207; age = [19.6 ± 1.3] years) actively participating in their college/university's MB during the 2019 football season completed an online survey to characterize demographics, medical history, medication and supplement use, and nutrition behaviors. Chi-square and binomial logistical regressions assessed associations between categorical variables. Previous EHI was reported by 50.6% of MB artists, with 466 (76.3%) experiencing exertional heat exhaustion and 31 (5.1%) exertional heat stroke. More females reported exertional heat exhaustion overall (68.2%, p < 0.001) and in the previous year (73.3%, p < 0.001). Experiencing a previous EHI was significantly associated with having a mood/neurological condition (63.5%, p < 0.001), diagnosed (74.3%, p = 0.004) or perceived eating disorder (66.7%, p < 0.001), and taking prescription medications (59.4%, p < 0.001), over-the-counter medications (58.9%, p = 0.002), and supplements (55.4%, p = 0.037). Half of collegiate MB artists reported experiencing previous EHIs and engaged in behaviors known to increase EHI risk. MB artists should complete pre-participation examinations to identify pre-existing medical conditions and risks for adverse medical events. Healthcare providers working with MB artists should develop policies and procedures to mitigate EHI risks and occurrence.
The integration of exercise prescriptions into cancer adjuvant therapy presents challenges stemming from the ambiguity surrounding the precise mechanism through which exercise intervention mitigates the risk of hepatocellular carcinoma (HCC) mortality and recurrence. Elucidation of this specific mechanism has substantial social and clinical implications. In this study, tumor-bearing mice engaged in voluntary wheel running exhibited a notable decrease in tumor growth, exceeding 30%. Microarray analysis revealed an upregulation of cytokine-related pathways as a potential explanation for this effect. The inclusion of granulocyte-macrophage colony-stimulating factor (GM-CSF) was found to enhance tumor cell proliferation, while the absence of GM-CSF resulted in a marked inhibition of tumor cell growth. The findings suggest that exercise-induced serum from mice can impede the proliferation of mouse tumor cells, with the adipokine chemerin inhibiting the growth factor GM-CSF. Additionally, exercise was found to stimulate chemerin secretion by brown adipose tissue. Chemerin suppression led to a reduction in the inhibition of tumor cell proliferation. The results of this study suggest that exercise may stimulate the release of adipokines from brown adipose tissue, transport them through the blood to the distant tumor microenvironment, and downregulate GM-CSF expression, alleviating tumor immunosuppression in the tumor microenvironment, thereby inhibiting at HCC progression. These findings provide a theoretical basis for incorporating exercise prescription into cancer treatment.
It is well-known that not meeting the 24-hours (h) movement guidelines, including insufficient physical activity (PA), excessive sedentary behavior (SB), inadequate sleep duration, and their combinations, are independent risk factors for noncommunicable diseases (NCDs). The prevalence of not meeting the guidelines is high across the world, especially in China where has one of the largest population. Some studies have estimated the economic cost of insufficient PA in China, which is useful to guide policymakers to develop and implement effective health actions. However, several research gaps should be discussed and addressed for better evidence base and decision making. This commentary aims to provide a research insight into gaps and recommendations related to the analysis of economic cost of not meeting the 24-h movement guidelines. Some major research gaps can be indicated, including less research attention on excessive SB and inadequate sleep, limited evidence regarding NCDs associated with not meeting all 24-h movement guidelines considered in economic cost analysis, absence of evidence on estimated cost of not meeting the guidelines, and the adherence to methodological guide. Future research is required to address the gaps to guide effective health policy development in China. We hope that this commentary can play an important role in updating research evidence and advancing policy practice.