Evidence-Based Effects of High-Intensity Interval Training on Exercise Capacity and Health: A Review with Historical Perspective

Exploring the gut-exercise link: A systematic review of gastrointestinal disorders in physical activity

BACKGROUND

The relationship between exercise and gastrointestinal (GI) health is complex and bidirectional. While moderate exercise generally promotes gut health by enhancing motility, reducing inflammation, and supporting microbial balance, intense or prolonged physical activity may exacerbate GI symptoms, particularly in individuals with pre-existing digestive disorders. A deeper understanding of this interplay is essential for optimizing both exercise performance and GI well-being.

AIM

To synthesize current evidence on exercise-related GI disorders, exploring the prevalence, mechanisms, risk factors, and management strategies associated with exercise-induced GI symptoms.

METHODS

Following PRISMA guidelines, comprehensive searches of databases, including PubMed, Scopus, Web of Science, and EMBASE were conducted. Studies were included if they focused on exercise-induced GI disorders, encompassed randomized controlled trials, cohort studies, case-control studies, and cross-sectional designs, and addressed symptoms across various exercise modalities. Data were extracted and analyzed to identify patterns and implications for clinical and athletic practice.

RESULTS

A total of 231 studies met the inclusion criteria, highlighting both the benefits and risks of exercise on GI health. Regular moderate-intensity exercise, including activities such as walking, cycling, and yoga has been associated with improved GI function in conditions like gastroesophageal reflux disease, irritable bowel syndrome, inflammatory bowel disease, and constipation. These benefits are attributed to enhanced intestinal motility, reduced systemic inflammation, and improved gut barrier integrity. Additionally, exercise plays a role in regulating the gut-brain axis, with practices like yoga and Tai Chi demonstrating particular effectiveness in alleviating functional GI disorders. Conversely, high-intensity or prolonged exercise may contribute to symptoms such as nausea, diarrhea, and abdominal pain due to mechanisms like splanchnic hypoperfusion and increased intestinal permeability. Individual factors, including fitness level, dietary habits, hydration status, and underlying GI conditions, significantly influence the body’s response to exercise.

CONCLUSION

Moderate-intensity exercise is a beneficial and well-tolerated intervention for promoting GI health, whereas high-intensity activities require careful monitoring, particularly in individuals with pre-existing GI disorders. Personalized exercise and dietary strategies are essential for balancing the benefits of physical activity with the risk of GI distress. Further research is needed to explore the long-term effects of exercise on gut microbiota composition and overall digestive health.

Diabetes Mellitus and Associated Vascular Disease: Pathogenesis, Complications, and Evolving Treatments

Diabetes mellitus is a metabolic disorder, characterized by elevated blood sugar levels (hyperglycemia) and insulin dysregulation. This disease is associated with morbidity and mortality, including significant potential vascular complications. High levels of hyperglycemia lead to not only elevated levels of reactive oxygen species but also advanced glycation end products, which are detrimental to the vascular endothelium and reduce protective compounds such as nitric oxide and prostacyclin. This damage contributes to the development of both macrovascular and microvascular complications. The present investigation explores the pathophysiological mechanisms of diabetic vascular complications and evaluates current management strategies, including lifestyle modifications, pharmacological treatments, and emerging therapies. The review underscores the importance of ongoing progress in diabetes management and patient education to lead to optimal patient-health outcomes and quality of life for individuals with diabetes mellitus.

Twelve-week interval training alters cytokines, adipokines and bone markers in women with obesity

This study aimed to investigate the effects of a 12-week high-intensity interval training on inflammatory cytokines, adipokines, and markers of bone turnover and examine whether high-intensity interval training-induced changes in inflammatory cytokines and adipokines were associated with changes in markers of bone turnover. Twenty-four women with obesity (mean [standard deviation]: age: 36.1 [3.38] years, height: 158.9 [11.9] cm, and body mass index: 31.9 [1.5] kg/m2) were randomly assigned to either control (n=10) or high-intensity interval training (n=14) groups. Body mass (- 2.7%), fat mass (- 15%), and percent body fat (- 6.2%) significantly decreased (p<0.05), while the predicted V̇O2max increased (29.6%; p<0.001) following the high-intensity interval training program. The training program resulted in increased adiponectin (7.6%) and osteocalcin (11.3%; p<0.05) and reduced tumor necrosis factor alpha (66.1%), interleukin-1α (18.6%), C-reactive protein (24.0%), leptin (21.5%), and carboxy-terminal telopeptide cross-linking type one collagen (14%; p<0.05). When high-intensity interval training and control groups were analyzed separately, training-induced changes in inflammatory cytokines and adipokines were not associated with changes in bone turnover markers (p>0.05), whereas significant associations were found when the data of the groups were analyzed together (p<0.05). In conclusion, a 12-week high-intensity interval exercise program improves the inflammatory state, adipokines, markers of bone turnover, cardiorespiratory fitness, and body composition in women with obesity.

The role of coenzyme Q10 in exercise tolerance and muscle strength

Context: Coenzyme Q10 (CoQ10) is a vital compound found in nearly all cells, and in mitochondria, it facilitates ATP production, and its reduced form acts as a powerful antioxidant, neutralizing reactive oxygen species (ROS) and preventing oxidative damage. Notably, during intense or endurance exercise, the body's increased energy demands and ROS production can lead to oxidative stress, muscle fatigue, inflammation, and exercise-induced muscle damage (EIMD).

Objectives: This review will explore the mechanisms of CoQ10, its impact on exercise performance to be addressed.

Results: CoQ10 has been shown to counteract these effects by supporting mitochondrial function, cell membranes, and reducing ROS. Research has demonstrated that CoQ10 supplementation lowers lipid peroxidation, reduces muscle damage indicators like creatine kinase (CK), lactate dehydrogenase (LDH-5 or LDH M), and myoglobin (Mb), and accelerates recovery from EIMD. Nevertheless, the impact of CoQ10 on performance has varied depending on factors such as dosage, duration, exercise type, and individual characteristics.

High-intensity interval training exercise decreases brain CB1 receptor levels in male and female adult rats

The numerous health benefits of exercise are well-documented, including its efficacy in treating substance use disorders (SUDs). Several exercise regimens have been proposed; however, the most effective regimen for patients with addiction has yet to be elucidated. High-intensity interval training (HIIT) exhibits considerable potential compared to aerobic and resistance exercise. Dopamine signaling is recognized as a key neurobiological mechanism contributing to HIIT's therapeutic potential for SUDs; however, the role of the endocannabinoid system in this context is not well understood. The present study investigated the effects of HIIT exercise on endocannabinoid signaling by measuring cannabinoid receptor 1 (CB1R) binding in the brains of male and female rats using [3H]SR141716A autoradiography. Male and female rats were separated into sedentary and HIIT exercise groups. For six weeks, exercise was completed daily on a treadmill for 30 min (10 3-min intervals) progressively increasing speed to 0.8 mph (21.5 m/min). The HIIT program significantly reduced CB1R binding in both sexes across multiple brain regions, including the striatum, thalamus, and distinct areas of the cortex. Sex differences were observed wherein males exhibited greater CB1R binding than females across brain regions, including the cerebellum, striatum, and parts of the cortex. Males experienced an increase in mean cerebellum CB1R binding due to HIIT, whereas females showed no effect in this region. The results suggest HIIT exercise can modulate endocannabinoid signalling by way of decreased CB1R binding. These findings further support the intensity dependence of endocannabinoid modulation and highlight potential pathways for exercise-induced neurobiological and behavioural change.

Methodological and aerobic capacity adaptations of high-intensity interval training at different altitudes in distance runners: A comprehensive meta-analysis

High-intensity interval training (HIIT) in hypoxia has demonstrated superior increases in aerobic capacity (VO2 max) adaptations, but this has not been explored in distance runners. This study examined the methodological and VO2 max adaptations of HIIT under different altitude conditions in distance runners. We searched the PubMed, ProQuest, Europe PMC, ScienceDirect, and Cochrane databases until August 2024. Among the 1183 reviewed studies, six studies were included. The PEDro score determined the methodological quality, and a meta-analysis was performed using Jamovi software. The results revealed that VO2 max improved more in hypoxic (4.4%-13%) HIIT than in normoxic (1%-8.3%) HIIT. The meta-analysis results revealed that the effect of HIIT under hypoxia on the VO2 max overall standardized mean difference (SMD) was 0.68, with a 95% confidence interval [0.3, 1.06], p < 0.001. Conversely, the pooled SMD was not related to the type of hypoxia (p = 0.4), training status (p = 0.36), intervention week (p = 0.82), and sex (p = 0.32). In conclusion, HIIT under hypoxia achieves a greater VO2 max improvement than normoxia. Endurance athletes and coaches could plan to benefit from such training. However, studies on females using different HIIT protocols and participants at different natural altitudes are limited. This review is registered under the PROSPERO CRD42024578473.

The Role of Plant-Based Nutrition and Exercise in Metabolic Syndrome: A Narrative Review

BACKGROUND/OBJECTIVES

Metabolic syndrome (MetS) is a prevalent health condition characterized by central obesity, insulin resistance, hypertension, and dyslipidemia, increasing the risk of cardiovascular disease and type 2 diabetes. Lifestyle interventions, particularly plant-based nutrition and exercise, are essential for managing MetS. While both strategies are well-documented independently, their synergistic effects remain less explored. This narrative review integrates findings from both domains to evaluate their combined impact on metabolic syndrome. The review examines the individual and combined impacts of plant-based nutrition and exercise on MetS-related metabolic dysfunction.

METHODS

A comprehensive review of 114 peer-reviewed studies was conducted to assess the role of plant-based diets and structured physical activity in improving insulin sensitivity, lipid profiles, inflammation, and weight management. Studies investigating the mechanisms through which dietary components and exercise modalities influence metabolic health were analyzed, along with behavioral and psychological factors affecting long-term adherence.

RESULTS

Plant-based diets, particularly those high in fiber, polyphenols, and healthy fats, improve glucose metabolism, reduce inflammation, and enhance cardiovascular health. Exercise complements these benefits by increasing insulin sensitivity, promoting fat oxidation, and improving lipid metabolism. When combined, plant-based nutrition and exercise provide superior metabolic outcomes, including greater reductions in visceral adiposity, improved endothelial function, and enhanced glycemic control.

CONCLUSIONS

Plant-based nutrition and structured exercise are effective strategies for managing MetS. Their synergistic effects highlight the importance of integrated lifestyle interventions for long-term metabolic health.

The role of resistance exercise-induced local metabolic stress in mediating systemic health and functional adaptations: could condensed training volume unlock greater benefits beyond time efficiency?

The majority of "specialised" exercise configurations (e.g., supersets, drop sets, blood flow restriction) are being assessed as "shortcuts" to hypertrophy and strength improvements. However, these advanced training techniques may also offer significant benefits for systemic health and functional outcomes across recreational and clinical populations via locally induced metabolic responses. Stress-regulating mechanisms are known to enhance the body's resilience by facilitating allostasis, the process of coordinating adaptive processes in reaction to stressors such as physical training. Yet, the role of the local metabolic stress provoked by resistance exercise has not gained much research attention despite its wide potential. Positive effects are not only linked to improved muscular endurance, hypertrophy and strength via primary and secondary mechanisms, but also to the release of myokines, hormones, microRNAs, immune factors, inflammatory substances and other endocrine molecules that initiate numerous health-promoting modifications on a systemic level. Resistance exercise strategies that maximise the local accumulation of metabolites are not well defined, although high volume, close proximity to failure and shorter rests seem to be a necessity. Additionally, blood flow restriction training provides a potent alternative for inducing local acidosis, thereby triggering several pathways associated with improved immunity and physical function even in remote muscle tissues. Future research is warranted to further explore advanced resistance training techniques, as these approaches may offer comparable benefits for physical and mental health to those seen with other forms of exercise such as high-intensity interval training and heavy resistance training.

Implementing High-Intensity Interval Training in Physical Education: Effects on Adolescents' Exercise Motivation

(1) Background: The aim of this study was to determine the effects of high-intensity interval training (HIIT) implemented in physical education classes on adolescents' motivation for exercise. (2) Methods: This study involved 60 male adolescents (16.23 ± 0.6 years) recruited from a local high school who were randomly assigned to either the HIIT group or the control group (CG). The Exercise Motivation Inventory-2 (EMI-2) questionnaire was used to assess how participation in a HIIT program influenced the motivation to exercise among adolescents. The experimental program consisted of a 12-week HIIT program, integrated into the preparatory part of physical education classes. Sessions were held twice weekly, with each session lasting ~10 min. The HIIT group performed the Tabata protocol, which consisted of two 4 min sequences of eight different high-intensity exercises (burpees, split jumps, jumping jacks, push-ups, wall ball, crunches, frog jumps, and Russian twists), each lasting 20 s with 10 s rest intervals, separated by a 1 min recovery period. The control group conducted the traditional moderate-intensity warm-up exercises for the same total duration. After the warm-up protocols, both groups continued with the same physical education classes, which included a variety of instructional and moderate-intensity activities. (3) Results: A significant time × group interaction was observed for social recognition (p = 0.04; partial eta squared η2p = 0.079, medium effect), indicating that HIIT had a superior effect compared to CG. Affiliation also showed a significant improvement in the HIIT group (p = 0.02), while no significant changes were noted in the CG (p = 0.35). Similarly, competition significantly increased in the HIIT group (p = 0.02), whereas no significant differences were found in the CG (p = 0.74). For all other motivational factors, no significant effects of time or group factors were found (p > 0.05). (4) Conclusions: This study highlights the positive effects of school-based HIIT on male adolescents' motivation, particularly in the area of social recognition.

Guidelines for animal models of endurance and resistance exercise

BACKGROUND

This mini-review details the guideline for implementing the most common exercise patterns in small laboratory rodents (mice/rats) and the advantages and disadvantages of each, in ways that are comparable to humans. Also, criteria for targeted selection and control of workload and intensity of activity are proposed in different exercise programs.

NEW METHOD

As an available and low-cost intervention in physiological, biochemical and cellular-molecular assessments, different exercise programs can be effective in the prevention/treatment of many skeletal-structural, behavioral and neurodegenerative disorders. Exercise tolerance/intolerance is an indicator of the complex function of the physiological, metabolic, neuromuscular, cardiovascular and respiratory systems, and in this sense, animal models of exercise are of interest to researchers by creating a controllable and precise environment.

RESULTS

Considering the different species of laboratory animals and various exercise paradigms, selecting the type, intensity and duration of the program in an optimal manner is a difficult task, especially in conditions such as old age or illness, and if necessary, existing research tools and protocols should be reviewed. In fact, one of the most attractive applications of exercise models is the discovery of preventive/therapeutic strategies for many disorders, which necessitates more knowledge about exercise protocols.

CONCLUSIONS

Animal models of endurance/resistance exercise on land/water make it possible to evaluate physiological/pathological conditions. However, to obtain optimal and reproducible results in human samples, the effectiveness of anesthetic drugs, surgical procedures, and the stress caused by exercise tools and equipment must be carefully controlled.

Effects of 10 weeks of walking-based exercise training on resting substrate oxidation in postmenopausal women with obesity

BACKGROUND AND AIMS

Accumulating evidence supports the effectiveness of moderate-intensity aerobic training on metabolic health, with limited studies investigating change in resting substrate oxidation. The aim of this study was to explore whether 10 weeks of walking-based aerobic training would alter substrate oxidation in postmenopausal women with obesity.

METHODS AND RESULTS

Twenty-four postmenopausal women with obesity who were assigned into the control (n = 12) or exercise groups (n = 12) undertook a 10-week aerobic training program (3 d·week-1) that involved walking exercises at 50-70% of heart rate reserve on a treadmill, with exercise volume increased from 25 to 40 min·day-1. Resting metabolic rate (RMR) and body composition were measured pre- and post-training. Whole-body substrate oxidation was calculated using respiratory data collected during RMR measurement via indirect calorimetry. No significant change was noted (p > 0.05) in resting fat oxidation and carbohydrate oxidation in the exercise group. Resting respiratory exchange ratio and RMR did not alter in response to the training program (p > 0.05).

CONCLUSION

Our results show that a 10-week of moderate-intensity aerobic training does not modify substrate oxidation in postmenopausal women with obesity.

Effects of resistance training vs high intensity interval training on body composition, muscle strength, cardiorespiratory fitness, and quality of life in survivors of breast cancer: a randomized trial

PURPOSE

Breast cancer treatments often lead to unfavourable changes in body composition, physical fitness, and quality of life (QoL). We compared the effects of resistance training (RT) and high-intensity interval training (HIIT) on these outcomes in survivors of breast cancer.

METHODS

Twenty-eight survivors of breast cancer, post-treatment (Stage I-III), aged 55.5 ± 8.8 years and body mass index 27.9 ± 5 kg/m2 were randomly allocated to a 12-week supervised RT (n = 14) or HIIT (n = 14) intervention, 3 days per week. Body composition (dual energy x-ray absorptiometry), upper and lower body muscle strength (1-repetition maximum), cardiorespiratory fitness (CRF) (Ekblom Bak Cycle Test), and QoL domains (EORTC QLQ-C30 and EORTC QLQ-BR45) were assessed at baseline and 12 weeks.

RESULTS

There were no significant differences between groups at baseline. Exercise attendance ranged from 81 to 85%. Between groups, there were significant differences (p ≤ 0.001) after 12 weeks in chest press strength for RT (mean difference [MD] = 4.7 kg) and CRF for HIIT (MD = 1.9 ml/min/kg). Within groups, there were significant improvements (p < 0.05) for % lean mass and % fat mass in both RT and HIIT, as well as for upper and lower body muscle strength, CRF, and QoL domains. No major adverse events were noted.

CONCLUSION

Both exercise groups improved body composition, physical fitness, and QoL domains over 12 weeks of RT or HIIT, although mode-specific benefits were apparent with more substantial improvements in lean mass and muscle strength with RT and reductions in % fat mass and improved CRF with HIIT. Tailored exercise programs should address the specific health needs of each patient.

Using Metabolic Testing to Personalize Behavioral Obesity Treatment

Background

There are large individual differences in weight loss and maintenance. Metabolic testing can provide phenotypical information that can be used to personalize treatment so that people remain in negative energy balance during weight loss and remain in energy balance during maintenance. Behavioral testing can assess the reinforcing value and change in the temporal window related to the personalized diet and exercise program to motivate people to maintain engagement in healthier eating and activity programs.

Objective

Provide an expository overview of how metabolic testing can be used to personalize weight control. Ideas about incorporating behavioral economic concepts are also included.

Methods

A broad overview of how resting metabolic rate, thermic effect of food and respiratory quotient can be used to improve weight control. Also discussed are behavioral economic principles that can maximize adherence to diet and activity protocols.

Results

Research suggests that measuring metabolic rate can be used to set calorie goals for weight loss and maintenance, thermic effect of food to increase energy expenditure, and respiratory quotient to guide macronutrient composition of the diet and maximize fat loss. Developing programs that foster a strong motivation to eat healthier and be active can maximize treatment success.

Conclusion

Incorporating metabolic measures can personalize behavioral weight loss programs, and the use of behavioral economic principles can increase the probability of adherence and long-term success in weight control.

Qualitative Description of Exercise Perceptions and Experiences Among People With Human Immunodeficiency Virus in the High-Intensity Exercise to Attenuate Limitations and Train Habits Study

BACKGROUND

The benefits of physical activity (PA), specifically exercise, among older adults in general are well known. Yet globally, there is concern regarding limited engagement in PA, increased obesity, and frailty among older people with human immunodeficiency virus related to low levels of PA.

METHODS

We conducted in-depth interviews among 30 older, sedentary people with human immunodeficiency virus participating in the ongoing High-Intensity Exercise to Attenuate Limitations and Train Habits (HEALTH study, NCT04550676) between February 2021 and August 2022. A semistructured interview guide, informed by two minds theory, which frames behavior change as an intention-behavior gap between 2 neurocognitive systems, was used to elicit data from participants. Interviews explored general exercise perceptions, self-efficacy for exercise, mobile health intervention tailoring, outcome expectations, and PA goals. Thirty interviews from 33 participants were recorded and transcribed verbatim, and deductive and inductive thematic analysis were used using Dedoose.

RESULTS

Physical activity was defined as maintaining daily living activities and addressing health goals. Previous experiences with PA varied among participants and were influenced by chronic illnesses, including human immunodeficiency virus; motivation; work commitments; interest; and social support. Reported barriers to PA included antiretroviral adverse effects, comorbidities, aging, and the COVID-19 pandemic. Changes in health status, body changes, and relationships were identified as benefits of PA. Conversations with healthcare providers supporting exercise goals were perceived to be important but rarely received by the participants.

CONCLUSION

Understanding how older people with human immunodeficiency virus perceive PA is crucial to developing tailored strategies and structuring service delivery within the healthcare setting to promote a physically active life.

Overview of mechanisms related to citrulline malate supplementation and different methods of high-intensity interval training on sports performance: A narrative review

Regular exercise is a practical non-pharmacological approach to maintaining physical and mental health through rehabilitation and prevention of chronic diseases due to its cardiovascular, cardiorespiratory, neurological, and neuromuscular benefits. Despite awareness of the benefits of exercise, a "lack of time" has proven to be the most common impediment to regular activity. Thus, a time-efficient and potentially enjoyable training modality with growing popularity is high-intensity interval training (HIIT). HIIT incorporates intermittent bouts of work and recovery intervals performed at an intensity close to maximal oxygen consumption (VO2max). HIIT is considered to have equivalent or superior benefits compared to moderate-intensity continuous training (MICT). This narrative review focuses on the mechanisms of Citrulline Malate (CM) supplementation and various modes of HIIT on exercise performance. CM serves as a nitric-oxide enhancer leading to improved aerobic and anaerobic exercise performance by increasing muscle adenosine triphosphate (ATP) production, vasodilation, and blood flow to the active musculature and boosting work capacity. This article reviews the mechanisms related to CM supplementation and different modes of HIIT on exercise performance. Even though a single, acute 8 g dose of CM has been recommended, its mechanism of action remains to be seen due to the synergistic impact of both components (citrulline and malate). Moreover, the limited evidence for the standard level of supplement use and source of purchase results in athletes' self-prescription of supplements. Therefore, to reduce the risk of accidental doping or toxicity, further studies should continue to investigate the optimal dose, timing, mechanism of action, as well as reliable sources of purchase for CM consumption.

Exercise Training and Cardiac Rehabilitation in Patients After Percutaneous Coronary Intervention: Comprehensive Assessment and Prescription

Current guidelines on acute and chronic coronary syndromes recommend comprehensive and multidisciplinary exercise-based cardiac rehabilitation in Class I. Indeed, in patients after a percutaneous coronary intervention, this supervised and structured rehabilitation program improves cardiovascular risk and reduces adverse events and mortality. After an initial assessment, including a peak exercise capacity evaluation, patients follow a tailored multidisciplinary program consisting of aerobic and resistance exercise training, risk factor management, dietary counselling, physical activity counselling, weight control management, psychosocial support, and education. However, tailored management and exercise prescription require careful assessment and risk consideration of several variables such as left ventricular dysfunction, comorbidities, aging, coronary artery disease severity, physical activity capacity, and type of coronary syndrome. The functional and prognostic benefits of cardiac rehabilitation have been widely demonstrated in patients after a percutaneous coronary intervention; however, referral is still limited, although exercise should be strongly recommended to these patients in the context of cardiovascular prevention. Therefore, the aim of our article is to provide an updated, critical, and state-of-the-art review of exercise training and cardiac rehabilitation programs in patients after a percutaneous coronary intervention. Furthermore, practical approaches to the management of these patients with a multidisciplinary and personalized intervention will be provided.

The impact of 24-forms Tai Chi on alpha band power and physical fitness in young adults: a randomized controlled trial

Regular physical activity is beneficial for health, but research on interventions for young people's physical and mental health remains limited. Tai Chi may have potential benefits, but its effects on young adults are not well - studied. 45 college students were randomly assigned to a Tai Chi (TC) group or a control group. The TC group underwent 45-minute sessions, three times a week for 12 weeks. Physical health performance and alpha-band power of resting-state electroencephalography were measured before and after the intervention. Both groups improved in long jump performance (p < 0.05), but the TC group had a greater improvement (13.73 ± 15.54 vs. 4.91 ± 9.24 cm). The alpha-band power increased in the TC group and decreased in the control group. Tai Chi can enhance physical fitness and alpha-band power in college students, suggesting its potential as a health-promoting activity.

Impact of Probiotic Supplementation and High-Intensity Interval Training on Primary Dysmenorrhea: A Double-Blind, Randomized Controlled Trial Investigating Inflammation and Hormonal Modulation

Background: Dysmenorrhea, categorized as primary (PD) or secondary (SD), significantly affects females during their reproductive years, impairing quality of life, performance, and social relationships. Alongside medical treatment, exercise and probiotics are complementary measures for managing PD and promoting health. This study examined the impact of probiotic supplementation and high-intensity interval training (HIIT) on PD severity, physiological modulation, and physical fitness. Methods: Participants, recruited according to the primary dysmenorrhea criteria, were divided into non-PD (control) and PD groups, with the PD group further classified into dysmenorrhea (Dysmen), dysmenorrhea with probiotics (DysmenPro), dysmenorrhea with exercise (DysmenEx), and dysmenorrhea with both (DysmenExPro). Interventions included 10 weeks of HIIT and probiotics. Pre- and post-intervention assessments included questionnaires on premenstrual and menstrual symptoms, physical fitness evaluations, and blood sample analyses for biochemical, hormonal, and prostaglandin levels. Results: HIIT significantly reduced premenstrual symptoms, menstrual distress, and pain severity, likely due to hormone (estradiol, prolactin, progesterone, cortisol) modulation and decreased inflammation (high-sensitivity C-reactive protein, PGE2, PGF2α). Cardiovascular endurance and explosive strength showed improvement through high-intensity interval training (HIIT), whereas probiotics had no significant effect on these aspects of physical fitness. While probiotics reduced premenstrual and menstrual distress symptoms, they had no notable impact on pain, inflammation, or hormone levels. Dysmenorrhea-related discomforts were correlated significantly with inflammation and hormones. Conclusions: The intervention strategy involving probiotics and HIIT exercise may be utilized as an alternative and complementary treatment to alleviate PD symptoms. Furthermore, this strategy could also be incorporated into educational health plans to promote women's health and potentially prevent gynecological disorders in the adolescent population.

A Systematic Review and Meta-Analysis on Aerobic Fitness Dynamics in Post-COVID-19 Athletes: Implications in the Return-to-Play Performance

Maximal oxygen uptake (V.O2max) assesses athletic performance; however, its values are inconsistent in post-COVID-19 athletes. This study aimed to analyze the dynamics of V.O2max in post-COVID-19 athletes. Observational studies were identified by screening the PubMed database published up to 17 July 2023. The initial electronic search found 320 studies. Of these, 26 employing the cardiopulmonary exercise test (CPET) to assess aerobic fitness were selected. Of the 2625 pooled athletes, 1464 were infected and considered as the post-COVID-19 group, either asymptomatic or symptomatic, while the remaining 1161, who were uninfected or had V.O2max results prior to infection, were defined as the infection-free group. Age and V.O2max were differently distributed between post-COVID-19 athletes and those without infection (p = 0.03 in both). Persistent symptoms athletes had 8 mL/Kg/min lower V.O2max than those without infection (p = 0.04). In addition, post-infected athletes who underwent CPET after 12 weeks showed a significant reduction of 2.9 mL/Kg/min in V.O2max according to the increase in body mass index (BMI). The pooled analysis showed that aerobic fitness was reduced in athletes post-COVID-19. V.O2max was negatively correlated with BMI in those who underwent CPET at 12 weeks, suggesting that symptoms persist beyond 12 weeks, affecting return-to-play.

Correlation of Sit-to-Stand Test and 6-Minute Walk Test to Illustrate Cardiorespiratory Fitness in Systolic Heart Failure Patients

OBJECTIVE

To prove 5-time sit-to-stand (5-STS) and 30-second sit-to-stand (30sSTS) tests in assessing cardiorespiratory fitness in chronic heart failure (HF) patients with systolic dysfunction. Alternative tests, such as 5-STS and 30sSTS, may be used to assess cardiorespiratory fitness in patients with HF but have not been thoroughly evaluated. Thus, this study aimed to prove 5-STS and 30sSTS tests in assessing cardiorespiratory fitness in chronic HF patients with systolic dysfunction.

METHODS

A cross-sectional study was done, evaluating chronic HF patients with systolic dysfunction that have received optimal guideline directed medical treatment for at least 3 months. All patients underwent the same intervention on the same day, starting with an initial 5-STS test, followed by a 30sSTS, and a 6-minute walk test (6MWT).

RESULTS

A total of 34 patients were enrolled in this study. The median left ventricular ejection fraction was 44% (interquartile range=34%-48%). Mean values of 5-STS, 30sSTS, and 6MWT were 13.90±4.72, 13.29±3.38, and 463.65±87.04, respectively. 5-STS showed moderate correlation with 6MWT (r=-0.436, p=0.01). However, the 30sSTS revealed strong correlation with 6MWT (r=0.629, p<0.001).

CONCLUSION

The 30sSTS test had strong correlation with 6MWT. It could be used to illustrate cardiorespiratory fitness in chronic HF patients with systolic dysfunction.

Relationship between psychological empowerment, physical activity enjoyment, and response to a HIIT Program in physically inactive young women: a prospective multicentre study

BACKGROUND

This study aimed to investigate the relationship of psychological empowerment and enjoyment of physical activity with changes in physical activity levels, sleep quality, and muscular endurance following a high-intensity interval training (HIIT) program in physically inactive young women.

METHODS

A total of 61 physically inactive young women (age: 20.1 ± 2.7 y) were recruited to participate in a six-month HIIT intervention delivered via a smartphone app. Outcome measures included physical activity levels (MET-min/week), muscular endurance (plank test), and sleep quality through the Pittsburgh Sleep Quality Index (PSQI). The Healthy Lifestyle and Personal Control Questionnaire (HLPCQ) and the Physical Activity Enjoyment Scale (PACES) were used to assess psychological empowerment and enjoyment, respectively. Repeated measures ANOVA and covariate analyses were performed to evaluate the impact of the intervention and the role of psychological empowerment and enjoyment.

RESULTS

At 6 months, significant improvements in physical activity (p < 0.001; ηp²=0.336) and muscular endurance (p = 0.005; ηp²=0.085) were observed, with large and moderate effect sizes, respectively. The PACES showed a significant interaction with time for MET-min/week (F = 11.67, p = 0.001, ηp²=0.129), suggesting that enjoyment influenced the increase in physical activity. No significant differences in sleep quality were observed (p > 0.05).

CONCLUSION

Enjoyment plays a crucial role in the response to HIIT programs among physically inactive young women, particularly in improving weekly physical activity levels. Psychological training showed no significant relationship with the outcomes studied.

High-intensity interval training to improve cardiorespiratory fitness in a patient with frailty and multimorbidity: A case report

BACKGROUND

Low cardiorespiratory fitness predicts worse postoperative outcomes, exacerbated by age and frailty. Preoperative High-Intensity Interval Training (HIIT) improves cardiorespiratory fitness and postoperative outcomes but is challenging to implement in frailty due to perceived risks.

PURPOSE

The aim of this case report was to demonstrate feasibility of HIIT in a patient with frailty and multimorbidity.

CASE PRESENTATION

An 83-year-old frail male with atrial fibrillation and limited mobility presenting with locally advanced rectal cancer was assessed as unfit for major surgery unless his cardiorespiratory fitness improved. Initial cardiopulmonary exercise testing demonstrated low cardiorespiratory fitness (peak oxygen consumption (V ˙ O2peak) of 11.45 mL·min-1·kg-1). He subsequently underwent 15 supervised HIIT sessions targeting a Rating of Perceived Exertion ≥ 15.

OUTCOMES

The patient demonstrated initial substantial improvements in his physical condition, increasing maximal work rate from 27.5 W to 55 W. However, there was no additional progress following session eight. At his post-exercise CPET he rapidly fatigued, resulting in a V ˙ O2peak of 7.4 mL·min-1kg-1. Clinical investigations revealed a worsening anemia with a hemoglobin of 92 g/L caused by an undiagnosed synchronous cecal tumor which was corrected preoperatively. Postoperatively, the patient recovered without complications and was successfully discharged home.

CONCLUSION

Personalized HIIT improved exercise duration and work rate and was associated with positive postoperative outcomes in this patient with frailty and multimorbidity. A unique feature of this case was the unexpected loss of training progress and V ˙ O2peak deterioration post-HIIT, which prompted further clinical investigations. These identified a worsening anemia and resulted in important changes in both the preoperative and intraoperative treatment.

Influence of the Type of Physical Training on the Physical Fitness of Army Cadets

INTRODUCTION

Military Physical Training programs represent a constant challenge for the Armed Forces to improve body composition indices and physical fitness levels. This study aimed to verify the influence of the type of training on the physical fitness and body composition of army cadets, using 2 strategies: a sports program (Athletes group) and conventional physical training (Traditional group).

MATERIALS AND METHODS

This study involved new entrant male cadets who were selected for the Athletes group (n = 243, 19.08 ± 1.23 years) or the Traditional group (n = 356, 18.89 ± 0.97 years), with assessments occurring before and after the period of training (31.4 ± 3.9 weeks). Dual-energy X-ray absorptiometry was used to measure the bone mineral content (BMC), fat mass (FM), percentage of fat mass (%FM), and lean soft tissue (LST). The physical tests evaluated the 3,000 m run (RUN), 50 m swim (SWIM), pull-ups (PULL) on the horizontal bar, push-ups (PUSH) on the ground, and abdominal flexion (SITUP).

RESULTS

Time × group interaction effects were observed for BMC (P < .001), LST (P < .023), RUN (P < .001), PULL (P = .006), PUSH (P < .001), SITUP (P = .007), and SWIM (P < .001). A significant effect of time was noted for all variables analyzed in both groups, except %FM. The Athletes group achieved better results in body composition and in PULL, PUSH, RUN, and SWIM at baseline and after the training period. The Traditional group demonstrated higher relative changes (%) after the training period in the LST (P = .001), PULL (P < .001), PUSH (P < .001), SITUP (P < .004), and SWIM (P < .001) compared to the Athletes group.

CONCLUSION

Both physical training programs improved body composition and physical performance.

Oxidative Stress and Cardiovascular Complications in Type 2 Diabetes: From Pathophysiology to Lifestyle Modifications

Type 2 diabetes mellitus (T2DM) is a chronic metabolic disorder that significantly increases the risk of cardiovascular disease, which is the leading cause of morbidity and mortality among diabetic patients. A central pathophysiological mechanism linking T2DM to cardiovascular complications is oxidative stress, defined as an imbalance between reactive oxygen species (ROS) production and the body's antioxidant defenses. Hyperglycemia in T2DM promotes oxidative stress through various pathways, including the formation of advanced glycation end products, the activation of protein kinase C, mitochondrial dysfunction, and the polyol pathway. These processes enhance ROS generation, leading to endothelial dysfunction, vascular inflammation, and the exacerbation of cardiovascular damage. Additionally, oxidative stress disrupts nitric oxide signaling, impairing vasodilation and promoting vasoconstriction, which contributes to vascular complications. This review explores the molecular mechanisms by which oxidative stress contributes to the pathogenesis of cardiovascular disease in T2DM. It also examines the potential of lifestyle modifications, such as dietary changes and physical activity, in reducing oxidative stress and mitigating cardiovascular risks in this high-risk population. Understanding these mechanisms is critical for developing targeted therapeutic strategies to improve cardiovascular outcomes in diabetic patients.

History and perspectives on interval training in sport, health, and disease

Exercise can be conducted as low-intensity continuous training (LICT) or a variety of higher intensity work/rest formats, collectively called interval training. Interval training was developed for athletes in the early 20th century. It was systemized in Sweden as Fartlek, and in Germany as die interval Method, in the 1930s. Most contemporary forms of interval training evolved from these progenitors. In essence, interval training allows a large volume of high-intensity or race specific training to be performed while controlling the development of fatigue. Adding interval training to LICT done by athletes adds about 2%-4% to performance achievable with LICT, which represents a competitively meaningful difference in performance (e.g., 4:25 vs. 4:00 over 1 mile). More recently, interval training has been applied to health- fitness participants and even to patients with health conditions. Studies indicate that a comparatively low volume of interval training can produce substantial improvement in physiologic capacity, in as little as 20% of training time versus LICT. There are data indicating that interval training can be reasonably pleasant, have good adherence, and is safe, even in patients. Although interval training was originally designed for athletics, the fundamental patterns of work versus recovery are remarkably similar in healthy adults and patients. Although the total volume of training and both absolute and relative intensity and magnitude of homeostatic disturbance are larger in athletes, the overall pattern of effort is the same in fitness participants and patients. Interval training can thus be characterized as an important step in the evolution of exercise training.

Exercise snacks and physical fitness in sedentary populations

Physical inactivity remains a pressing global public health concern. Prolonged periods of sedentary behavior have been linked to heightened risks of non-communicable diseases such as cardiovascular diseases and type 2 diabetes, while engaging in any form of physical activity can elicit favorable effects on health. Nevertheless, epidemiological research indicates that people often struggle to meet recommended physical activity guidelines, citing time constraints, lack of exercise equipment, and environmental limitations as common barriers. Exercise snacks represents a time-efficient approach with the potential to improve physical activity levels in sedentary populations, cultivate exercise routines, and enhance the perception of the health benefits associated with physical activity. We review the existing literature on exercise snacks, and examine the effects of exercise snacks on physical function and exercise capacity, while also delving into the potential underlying mechanisms. The objective is to establish a solid theoretical foundation for the application of exercise snacks as a viable strategy for promoting physical activity and enhancing overall health, particularly in vulnerable populations who are unable to exercise routinely.

Aerobic Exercise and Metformin: A Dual Approach to Enhancing Glycemic Maintenance in Type 2 Diabetes Mellitus

Type 2 diabetes mellitus (T2DM) is a widespread metabolic condition characterized by elevated glucose levels followed by deficiency in insulin secretion. Metformin notably decreased the incidence of T2DM by 31% and it exerts its effects through various signaling pathways. Databases searched included PubMed, Google Scholar, and Scopus from 2000 to 2024. One of the primary mechanisms involves AMPK activation which causes reduced lipogenesis and improved fatty acid oxidation in the liver and muscles. Key molecules affected by metformin include acetyl-CoA carboxylase (ACC) and sterol regulatory element-binding protein 1c (SREBP-1c), both involved in lipid synthesis regulation. Aerobic exercise has also emerged as a crucial component in managing T2DM due to its improved effects on hyperglycemia and insulin sensitivity. Key signaling pathways affected in T2DM include the PI3K/Akt, AMP-activated protein kinase (AMPK), and MAPK/ERK pathways which play essential roles in regulating glucose homeostasis, glycogenesis, and insulin secretion. When comparing the mechanisms and efficacy of aerobic exercise and metformin, it becomes evident that aerobic exercise primarily enhances physical fitness and metabolic function, while metformin exerts its effects through biochemical pathways involving AMPK activation. Aerobic exercise and metformin are effective for managing T2DM, though they operate through different mechanisms. Regular aerobic exercise improves insulin sensitivity, enhances cardiovascular health, and promotes weight loss, while metformin primarily decreases hepatic gluconeogenesis and enhances insulin secretion. Understanding the intricate signaling pathways affected by metformin and aerobic exercise provides valuable insights into its mechanisms of action and clinical implications for treating diabetic patients effectively.

Effects of Workplace Supervised Exercise on Psychological Capital: An Intervention Study

Public employees face a growing array of professional challenges, and psychological capital (PC) has emerged as a valuable resource to address them. Workplace supervised exercise (WSE) programs can improve physical fitness and personal resources, though their adoption in organizations is limited. This study examines the impact of a long-term WSE program on the psychological capital of public administration employees. Fifty-five participants completed PC questionnaires and attended at least 40% of the sessions; 49.1% were women, and 40% were over 50 years old (age range: 24-73 years). A quasi-experimental design without a control group was used with a longitudinal design, and a nine-month WSE program (from October to June) was implemented. The data show gender-specific variations in PC patterns. Among men, incremental increases were observed over the three measurement intervals, with statistical significance achieved only in self-efficacy and hope. Among women, an upward trend was observed between October and February without statistical significance, followed by a slight decline. The results suggest that the WSE program may enhance personal resources, particularly hope and self-efficacy, highlighting the importance of tailoring WSE programs to the specific characteristics of the target group.

Motivators and barriers to exercise in college students compared to faculty and staff

Objective: Compare the barriers and motivators to exercise in faculty/staff compared to students. Participants: Students and faculty/staff who were enrolled or employed at a college in Pennsylvania were emailed a link to a 91-question online Qualtrics® survey. Methods: The survey collected demographic information as well as physical activity habits and included the Barriers to Being Active Questionnaire, Motivations for Physical Activities Measure, and Behavioral Regulation in Exercise Questionnaire. Results: Faculty/staff (n = 69) were older and had a higher BMI than students (n = 97) (both p < 0.001). There were no differences in physical activity habits between groups. Faculty/staff reported social influences being a significantly (p = 0.02) greater barrier to physical activity than students. Students reported appearance (p = 0.002) and competence (p = 0.02) to be significantly higher motivators compared to faculty/staff. Both groups reported moderate self-determined motivation. Conclusion: Appropriate strategies can be employed by identifying the motivators and barriers to physical activity in students and faculty/staff.

A Comparison of Physical Activity and Exercise Recommendations for Public Health: Inconsistent Activity Messages Are Being Conveyed to the General Public

We examined the similarities and differences between government-supported public health activity recommendations from the World Health Organization (WHO), the Centers for Disease Control and Prevention (CDC), the National Health Service (NHS), the Department of Health and Aged Care (DHAC), and one of the most renowned public health activity recommendations, the 10,000 Steps Program. The findings derived from our evaluation suggest a lack of consistency in public health activity recommendations, including the nomenclature used to describe aerobic activity, the amount of time required per week to meet the minimum recommendation for moderate and vigorous activity, and variations in the intensities required to meet aerobic activity recommendations. We also found that moderate-intensity activity (3.0 to less than 6.0 METS) is achieved across the lifespan with normal (i.e., mean), rather than vigorous, walking speeds; this suggests the MET level for moderate-intensity activity may need to be re-examined. The suggested strength activities must also be considered to ensure that the activities maintain or improve strength in the general public. Among the reviewed recommendations, none distinguished between physical activity and exercise, which may contribute to the low levels of exercise participation among the general public. Since exercise is medicine, the most recognized government-supported public health activity recommendations should place a greater emphasis on exercise over physical activity. Moreover, given the low levels of activity in the general public, more care should be given to provide a consistent, clear, and direct message regarding activity recommendations.

The impact of various mind-body exercises on cardiorespiratory function and quality of life in heart failure patients: A network meta-analysis

OBJECTIVE

This study aims to compare the relative effects of different mind-body exercises on cardiorespiratory function and quality of life in Heart failure (HF) patients, providing valuable insights for their rehabilitation.

METHODS

We conducted a search across seven Chinese and English databases, including China National Knowledge Infrastructure (CNKI) and Web of Science. A network meta-analysis was performed using STATA 14.0 within a frequentist framework.

RESULTS

A total of 38 studies were included, encompassing eight types of mind-body exercises. Ten studies reported peak VO2, indicating that dancing outperformed Tai Chi (MD:3.52, 95 % CI:6.74, -0.30) and Baduanjin (MD:2.34, 95 % CI:4.32, -0.36). Additionally, Pilates demonstrated greater effectiveness than Yijinjing, aside from Tai Chi (MD:5.10, 95 % CI:8.71, -1.49) and Baduanjin (MD:3.92, 95 % CI:6.50, -1.34). Twenty-one studies reported the six-minute walk test (6MTW), with only Tai Chi significantly improving 6MTW scores compared to the control group (MD: 50.77, 95 % CI: 8.12, 93.42). Twenty-three studies assessed left ventricular ejection fraction (LVEF), finding that Tai Chi (MD: 3.83, 95 % CI: 2.07, 5.59), Baduanjin (MD: 2.90, 95 % CI: 1.04, 4.76), and yoga (MD: 3.32, 95 % CI: 0.37, 6.27) significantly increased LVEF in HF patients. Nineteen studies evaluated quality of life, with the Liuzijue possibly being the most effective intervention (SUCRA: 98.9).

CONCLUSION

Different mind-body exercises have their own advantages in improving the heart function and quality of life of HF patients. In the future, higher-quality studies with larger samples are needed to further verify the validity of the results.

Effects of high-intensity interval training on selected indicators of physical fitness among male team-sport athletes: A systematic review and meta-analysis

BACKGROUND

Superior physical fitness and performance are essential in male team sports. Among a myriad of training methodologies, high-intensity interval training (HIIT) has gained popularity owing to its unparalleled efficiency and effectiveness. Previous studies have established that HIIT is a proven and effective approach for enhancing various physiological performance outcomes, particularly oxygen consumption capacity, in individual sports. Despite potential differences in training practices between male and female athletes, HIIT is recognized as an anaerobic training approach for team-sport athletes. This systematic review aimed to comprehensively and innovatively analyze the existing literature to examine the effectiveness of HIIT on oxygen consumption performance among male team-sport athletes.

METHODS

A comprehensive literature search was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines across the PubMed, SCOPUS, Web of Science, and SPORTDiscus databases until December 31, 2023. The inclusion criteria for this review encompassed research articles published in peer-reviewed journals that specifically focused on the impact of HIIT on the oxygen consumption performance of male players engaged in team sports. The study population exclusively consisted of male participants. The collected data included study characteristics, participant demographics, intervention details, and outcomes. Methodological quality assessment was performed using standardized criteria. The effect sizes (ESs) were calculated, and a meta-analysis was conducted using a random-effects model.

RESULTS

The literature search yielded 13 eligible studies encompassing 286 athletes aged 14-26 years. The meta-analysis showed statistically significant enhancements in maximal oxygen uptake (VO2max) in six studies (ES, 0.19-0.74; p < 0.005), Yo-Yo Intermittent Recovery Test (YYIRT) performance in six studies (ES, 0.20-2.07; p = 0.009), repeated-sprint ability total time (RSAtotal) in five studies (ES, 0.18-1.33; p < 0.001), and the best and average times for repeated-sprint ability (RSAbest and RSAmean, respectively) in four studies (ES, 0.47-1.50; p < 0.001). However, two studies did not report any significant differences in the outcomes of the Velocity in 30-15 Intermittent Fitness Test (VIFT) between the experimental and control groups (ES, -0.08 and -0.27; p = 0.87 and 0.443, respectively). Moreover, one study did not report any significant differences in the maximal aerobic speed (MAS) (ES, 0.41, p = 0.403).

CONCLUSIONS

HIIT significantly improved VO2max, YYIRT, and RSA; however, it did not appear to enhance VIFT and MAS performance, irrespective of age or competition level. These findings indicate that HIIT could serve as a valuable method for improving oxygen consumption performance (VO2max, YYIRT, and RSA) in male team-sport athletes, offering a time-efficient alternative to the traditional training methods. Further research is warranted to investigate its impact on performance outcomes in competitive settings and identify optimal HIIT protocols tailored to specific team sports.

Effects of high-intensity interval training versus moderate-intensity continuous training on vascular function among individuals with overweight and obesity-a systematic review

BACKGROUND

The study aimed to investigate and systematically review the evidence relating to the effects of high-intensity interval training (HIIT) versus moderate-intensity continuous training (MICT) on vascular function such as arterial diameter, arterial stiffness, pulse wave velocity, blood flow, etc. in individuals with overweight and obesity.

METHODS

The entire content of PubMed (MEDLINE), Scopus, SPORT Discus® (via EBSCO host), CINAHL, and Web of Science were searched. Only experimental research studies conducted in adult participants aged ≥18 years, published in English before January 2023 were included.

RESULTS

A total of 5397 studies were reviewed for the title and abstract with 11 studies being included for data extraction. The review resulted in a total of 346 individuals with overweight and obesity with body mass index (BMI) ranging between 25-36 kg/m2. HIIT and MICT intensities resulted in 85%-95% and 60%-70% maximal heart rate (MHR) respectively. Seven out of 11 studies showed some concerns about the overall risk of bias. Six of 11 studies reported improving vascular function following HIIT than MICT.

CONCLUSION

HIIT is a more effective and time-efficient exercise for enhancing vascular functions in individuals with overweight and obesity, leading to improvements in flow-mediated dilation by 3.9% and arterial diameter by 4.8%, compared to MICT.

Effects of a Six-Month Physical Activity Program on Health Risk Factors and Body Composition Among Overweight and Obese Middle-Aged Adults

Introduction. Physical activity is vital for preventing and managing lifestyle-related diseases, which pose significant health and socio-economic challenges. This study aimed to evaluate the effects of a six-month supervised physical activity program on health risk factors and body composition in middle-aged individuals with overweight or obesity. Methods. The study involved 166 men and women aged 30 to 65 years, with a body mass index (BMI) ranging from 26 to 35 and moderate to severe health risks. Participants of the study were engaged in a six-month physical activity training program designed in accordance with World Health Organization guidelines. Comprehensive assessments were performed at baseline and after the intervention, including measurements of various anthropometric and body composition parameters, as well as evaluations of functional performance. Fitness tests were also conducted to assess participants' physical capacity and to monitor improvements throughout the training period. Results. Baseline measures of body mass composition and age demonstrated a strong positive correlation with visceral fat rating (VFR) in both men (r = 0.364, p < 0.001) and women (r = 0.420, p = 0.002). Following the six-month training program, participants exhibited an average improvement of 30% (p < 0.001) in their Cooper endurance test results. The physical activity intervention positively impacted body mass index (BMI) and various body composition metrics, including fat mass, VFR, and muscle mass, across all participants and most subgroups (gender, BMI, and age). In males, training at higher maximum heart rate (HRmax) zones significantly contributed to a reduction in the percentage of fat mass (80-89% HRmax) and an increase in the percentage of muscle mass (70-79% and 80-89% HRmax). Conclusions. The study indicates that a six-month supervised physical activity program significantly improves health risk factors and body composition (visceral fat reduction and improvement in percent of fat and muscle mass) among middle-aged individuals with overweight or obesity. Therefore, we advocate for the integration of structured physical activity interventions into healthcare practices to effectively enhance health outcomes in this population.

Physical activity levels and musculoskeletal disease risk in adults aged 45 and above: a cross-sectional study

BACKGROUND

Musculoskeletal disease (MSD) is a major cause of disability among older adults, and understanding the role of physical activity (PA) in preventing these conditions is crucial. This study aimed to explore the association between PA levels and MSD risk among adults aged 45 and above, clarify the dose‒response relationship, and provide tailored guidelines.

METHODS

Using data from the China Health and Retirement Longitudinal Study (CHARLS), a cross-sectional analysis was conducted on 15,909 adults aged 45 and over. The study population was divided into MSD (n = 7014) and nMSD (n = 8895) groups based on musculoskeletal health status. PA levels were assessed using the International Physical Activity Questionnaire and categorized into low intensity physical activity (LIPA), moderate vigorous physical activity (MVPA), and vigorous physical activity (VPA). Multivariable logistic regression models and restricted cubic spline regression were used to examine the relationship between PA levels and MSD risk in middle-aged and older adults. Sensitivity analyses and stratified analyses were also performed.

RESULTS

The main outcome measures were musculoskeletal diseases prevalence and PA levels. MVPA and VPA reduced MSD risk by 19% [OR = 0.81, 95% CI (0.72, 0.90), P < 0.001] and 12% [OR = 0.88, 95% CI (0.79, 0.98), P < 0.05], respectively. What's more, after adjusting for confounding factors, VPA increased risk by 32% [OR = 1.32, 95% CI (1.04, 1.66), P < 0.05]. The relationship was nonlinear, showing a U-shaped pattern with age and hypertension status as significant moderators. The optimal PA energy expenditure was identified as approximately 1500 metabolic equivalents of tasks (METs) per week for adults aged 45-74, 1400 METs per week for those aged 75 and above, and 1600 METs per week for hypertensive adults aged 45 and older.

CONCLUSIONS

For adults aged 45 years and older, VPA significantly increases the risk of MSD. Adults aged 45 years and older should adjust their weekly METs based on their age. Additionally, those with hypertension should moderately increase their weekly METs to promote optimal musculoskeletal health.

High-intensity intermittent exercise increases serum levels of chitinase 3-like protein-1 and matrix metalloproteinase-9 in persons with multiple sclerosis

The study aimed to evaluate the effect of high-intensity intermittent exercise (HIIE) on serum levels of MMP-9 and CHI3L1 in multiple sclerosis. Study group received HIIE twice a week for 12 weeks, while control group received no treatment. In intra-group comparison, study group showed a significant increase in MMP-9 and CHI3L1 levels, while control group showed no significant difference. In intergroup comparison, a significant difference was found only in CHI3L1 levels after treatment. The increase in MMP-9 and CH3L-1 concentrations in study group suggests that these biomarkers may play a role in regulating specific skeletal muscle adaptations due to HIIE.

Changes in the force-time curve during a repeat power ability assessment using loaded countermovement jumps

Background

Repeat power ability (RPA) assessments traditionally use discrete variables, such as peak power output, to quantify the change in performance across a series of jumps. Rather than using a discrete variable, the analysis of the entire force-time curve may provide additional insight into RPA performance. The aims of this study were to (1) analyse changes in the force-time curve recorded during an RPA assessment using statistical parametric mapping (SPM) and (2) compare the differences in the force-time curve between participants with low and high RPA scores, as quantified by traditional analysis.

Materials and Methods

Eleven well-trained field hockey players performed an RPA assessment consisting of 20 loaded countermovement jumps with a 30% one repetition maximum half squat load (LCMJ20). Mean force-time series data was normalized to 100% of the movement duration and analysed using SPM. Peak power output for each jump was also derived from the force-time data and a percent decrement score calculated for jumps 2 to 19 (RPA%dec). An SPM one-way ANOVA with significance accepted at α = 0.05, was used to identify the change in the force-time curve over three distinct series of jumps across the LCMJ20 (series 1 = jumps 2-5, series 2 = jumps 9-12 and series 3 = jumps 16-19). A secondary analysis, using an independent T-test with significance accepted at p < 0.001, was also used to identify differences in the force-time curve between participants with low and high RPA%dec.

Results

Propulsive forces were significantly lower (p < 0.001) between 74-98% of the movement compared to 0-73% for changes recorded during the LCMJ20. Post hoc analysis identified the greatest differences to occur between jump series 1 and jump series 2 (p < 0.001) at 70-98% of the movement and between jump series 1 and jump series 3 (p < 0.001) at 86-99% of the movement. No significant differences were found between jump series 2 and jump series 3. Significant differences (p < 0.001) in both the braking phase at 44-48% of the jump and the propulsive phase at 74-94% of the jump were identified when participants were classified based on low or high RPA%dec scores (with low scores representing an enhanced ability to maintain peak power output than high scores).

Conclusion

A reduction in force during the late propulsive phase is evident as the LCMJ20 progresses. SPM analysis provides refined insight into where changes in the force-time curve occur during performance of the LCMJ20. Participants with the lower RPA%dec scores displayed both larger braking and propulsive forces across the LCMJ20 assessment.

Relationships between physical fitness and match running demands during a futsal congested-weeks training camp

This study examines the relationships between body composition, anthropometry and physical fitness measures, and internal and external load (match physical and running demands) during a congested period of an overseas futsal training camp. Eleven under-20 national futsal players participated in a eleven-day training camp. During the matches, exercise heart rate (HR) and locomotion profiles were recorded via a Polar Team Pro system as the players' internal and external load. The friendly matches were scheduled on the training camp's 2nd, 4th, 6th, 8th, and 10th days. A repeated-measures analysis of variance (ANOVA) and Pearson's correlation coefficient were used for statistical analysis. The results revealed significant differences in sprint (F = 2.74, p = 0.04, η2 = 0.21), accelerations (F = 3.63, p = 0.04, η2 = 0.27), and decelerations (F = 2.73, p = 0.04, η2 = 0.21) performance between the five matches (p < 0.05). Also, the overall body composition and physical fitness measures had large to very large correlations with match running demands during congested periods of futsal competition (p < 0.05). In conclusion, the baseline body composition and the overall physical fitness measures may be essential factors in match running demands during a congested futsal match period. Futsal players who perform better in the 30-15 Intermittent Fitness Test can sustain a greater volume of high-intensity accelerations during a congested period.

ASC speck serum concentrations, a component of sterile cellular inflammation, are associated with individual cardiopulmonary capacity

Aims

Exercise-induced cellular stress and sterile inflammation are of increasing interest. ASC specks are a component of the intracellular NLRP3-inflammasome and can be released into the blood. For example, serum ASC specks are increased after marathon running. We therefore tested whether ASC specks are potentially associated with the individual response to physical training and cardiopulmonary capacity.

Methods

We performed a prospective study in 45 healthy athletes. Blood samples were taken before and after cardiopulmonary exercise testing (CPET). ASC speck concentrations were quantitated using flow cytometry.

Results

Baseline ASC speck levels correlated with clinical parameters of body composition (height, weight, BMI) and parameters of cardiopulmonary performance (peak VO2, peak oxygen pulse, heart rate after exercise). Athletes with lowest baseline ASC speck concentrations have a significantly lower BMI (22.0 ± 1.8 vs. 24.9 ± 1.6 kg/m2), higher heart rate at rest (72 ± 10 vs. 58 ± 10 beats/min), lower peak VO2 (2692 ± 629 vs. 3404 ± 747 mL/min) and lower peak oxygen pulse (15.6 ± 3.4 vs. 20.7 ± 3.5 mL/heart rate). Overall, ASC speck concentrations showed no significant change after CPET (7.0 ± 4.5 vs. 8.0 ± 5.4 ASC specks/µL, p = 0.3). However, subgroup analysis revealed a significant increase in circulating ASC specks in athletes with the lowest baseline values (2.37 ± 0.84 vs. 8.43 ± 7.52 ASC specks/µL, p < 0.05). Athletes with an increase in ASC speck concentrations in response to CPET had a lower peak oxygen pulse compared to those with a decrease (17.1 ± 4.2 vs. 19.8 ± 4.1, p < 0.05).

Conclusion

Low ASC speck baseline values as well as an increase in response to exercise are associated with lower peak oxygen pulse in healthy athletes.

Assessing the criterion validity of the activPAL CREA v1.3 algorithm and ActiPASS 2023.12 software for detecting steps during a progressive treadmill-based laboratory protocol

Thigh-worn accelerometry is commonly implemented to measure step cadence. The default activPAL CREA algorithm is a valid measure of cadence during walking, but its validity during running is unknown. The ActiPASS software is designed to analyse tri-axial accelerometry data from various brands. We tested the validity of CREA v1.3 and ActiPASS 2023.12 to measure step cadence against manually-counted steps. Forty-five participants (26♀, 23.4 ± 4.6 years) completed 5 walking (6 min each, 2-4 mph) and 5 running treadmill (5-7 mph) stages (423 total stages completed). Based on equivalence testing, walking cadence (stages 1-5: 92-124 steps/min) from CREA was statistically equivalent (zone: <±2.2% of the manually-counted mean) to manual counts (92-125 steps/min). However, CREA underpredicted cadence during running stages (stages 6-10: 143-135 steps/min) by ~ 11-20 steps/min (p < 0.001). The ActiPASS-derived cadences were equivalent (zone: <±3.3%) to manual counts for all walking stages (99-127 steps/min) except Stage 1 (zone: ±10.5%). ActiPASS underpredicted cadences during running (stages 6-10: 137-153 steps/min) by ~ 10-16 steps/min (p < 0.001) compared to manual counts (stages 6-10: 154-164 steps/min). The CREA v1.3 algorithm is a valid measure of cadence during walking while ActiPASS 2023.12 is a valid measure of cadence during medium-fast walking. Further research is required to improve step cadence estimation across ambulation speeds.

The effect of aerobic and high-intensity interval training on plasma pentraxin 3 and lipid parameters in overweight and obese women

Background

It is unclear whether different exercise programs lead to an increase in the concentration of plasma Pentraxin3 (PTX3), an anti-inflammatory protein. This study aimed to investigate the effects of aerobic exercise (AE) and high-intensity interval training (HIIT) on plasma PTX3 levels in overweight and obese women.

Method

A total of 45 sedentary women aged between 32.26 ± 6.30 voluntarily participated in the study. The control group (CG, n = 15) was selected among normal-weight women. Women in the group of participants who partook in exercise consisted of overweight and obese women according to a random method, including the AE group (n = 15) and the HIIT group (n = 15). The AE session conducted was 50 min in duration and consisted of warm-up exercises (5 min), and primary exercises (40 min, basic aerobic-step exercises). HIIT consists of warm-up exercises (5 min), primary exercises (work intervals: 6-10 × 1 min (80-90% HRmax), rest intervals: 1 min (walk, 50% HRmax), 21-29 min running. The exercises were applied for three sessions/week for 12 weeks. Fasting blood samples were taken from all participants before and after exercise and their body composition was measured.

Results

As a result of two different 12-week exercises, serum PTX3 levels increased significantly by 47.53% in the AE group and 50.21% in the HIIT group (p < 0.01). It was determined that the mean PTX3 before and after exercise increased from 1.71 ± 0.43 to 2.47 ± 0.40 ng/dL and HIIT from 1.62 ± 0.39 to 2.31 ± 0.33 ng/dL. A significant decrease in body mass index (BMI) values were detected, approximately 5.81% in the AE group and 5.06% in the HIIT group (p < .01). A significant decrease was detected in glucose, insulin, HOMA-IR, LDL-C, and hsCRP whereas HDL-C and VO2max value increased significantly in both exercise groups (p < .05; p < .01). There were no significant differences in TG and TC levels between groups (p > .05). Also, no significant differences were found between the two types of exercises in terms of parameters. A significant negative correlation in the total sample was found between PTX3 with BMI, fat mass, LDL-C, and hsCRP.

Conclusion

The percentage change in PTX3 values was not different between exercise types, whereas PTX3 was increased with exercise, regardless of the type of exercise. It can be said that both aerobic and HIIT increase PTX3, VO2max levels and improve lipid metabolism in overweight and obese women.

Effects of aquatic and land high-intensity interval trainings on selected bio- and physiological variables among obese adolescents

Background

Obesity among adolescents have become a global public health problem. Exercises can effectively improve the bio-physiological factors of obese adolescents. High-intensive interval training (HIIT) has been applied to obese adolescents. Studies have reported that the Aquatic environment may bring the same or more positive exercise effects as the land environment. Therefore, the purpose of this study was to examine the effects of aquatic and land interventions on selected bio-and physiological variables among obese adolescences.

Methods

Twenty-eight obese adolescents who met the requirements participated in and completed this study. The participants were randomly assigned to Aquatic HIIT group (n=17) or Land HIIT group (n=11) for a four-week exercise intervention, 3 time/week. Each Intervention program was one-hour long, including 20 minutes of warm-up, 30 minutes of HIIT and 10 minutes of stretching and relaxation. Bio- and physiological variables including Anthropometry and body composition, Physical Function and blood pressure, and Lipid metabolism indexes were collected before and after the Aquatic and Land interventions.

Results

After four weeks of exercise interventions, the body mass, BMI, body fat rate, waist circumference, hip circumference and body water content were significantly reduced (p<0.05), and the lean body mass were significantly increased (p<0.05) in both groups. Both group exhibited significant effects in decreasing, systolic blood pressure (p<0.05), diastolic blood pressure (p<0.01), and increasing vital capacity and total energy consumption (p<0.05). The Aquatic HIIT group showed significant effects on reducing Rest heart rate (p<0.05), but no significant changes in Rest heart rate in Land HIIT group (p=0.364). The low-density lipoprotein cholesterol in both groups was significantly decreased (p<0.05). Moreover, the Aquatic HIIT group had significant better improvements (p<0.05) in lean body mass, waist circumference, waist-to-hip ratio, vital capacity and total energy consumption than Land HIIT group did.

Conclusions

The results of the present study demonstrated that in a short-term (4 weeks) both Aquatic and Land HIIT interventions may improve the body composition, physical function, blood pressure and low-density lipoprotein cholesterol (LDL-C) of overweight and obese adolescents. Furthermore, the Aquatic HIIT may be superior than the Land HIIT in weight control among the obese adolescents.

How Can Promoting Skeletal Muscle Health and Exercise in Children and Adolescents Prevent Insulin Resistance and Type 2 Diabetes?

Skeletal muscle secretome, through its paracrine and endocrine functions, contributes to the maintenance and regulation of overall physiological health. We conducted a narrative review on the role of skeletal muscle and exercise in maintaining glucose homeostasis, driving insulin resistance (IR), and preventing type 2 diabetes in pediatric populations, especially in the context of overweight and obesity. Myokines such as interleukin (IL)-6, IL-8, and IL-15, as well as irisin, myonectin, and myostatin, appear to play a crucial role in IR. Skeletal muscle can also become a target of obesity-induced and IR-induced inflammation. In the correlation between muscle, IR, and inflammation, the role of infiltration of the immune cells and the microvasculature may also be considered. It remains unclear which exercise approach is the best; however, combining aerobic exercise with resistance training seems to be the most effective strategy for managing IR, with high-intensity activities offering superior metabolic benefits and long-term adherence. Encouraging daily participation in enjoyable and engaging exercise is key for long-term commitment and effective glucose metabolism management. Promoting physical activity in children and adolescents must be a top priority for public health, not only in terms of individual quality of life and well-being but also for community health.

Evaluating the Effectiveness of the Annual Physical Training Plan for Masters +45 Women Half Marathon Athletes: A Guideline Model for Good Practices for Programming Effort Volume and Intensity

This study presents the implementation and results of the Annual Physical Training Program for Masters +45 Half Marathoners (PASm-12), focused on optimizing athletic performance through rigorous planning of training volume and intensity. PASm-12, structured over 12 mesocycles and 52 microcycles, was applied to 6 female runners with over 10 years of experience. The results indicate that the total running volume achieved (2347 km) was 90.2% of the volume proposed by PASm-12 (2603.2 km), with statistically significant differences in most mesocycles (Cohen's f2 = 6.24, t = -5.997, p = 0.002, indicating a large effect size). The training intensity was achieved at an average of 94.8% of what was proposed by PASm-12, with significant differences in several mesocycles (Cohen's f2 = 0.45, t = -1.972 to -3.984, p < 0.05, indicating a moderate to large effect size). The female runners' performances in field tests generally showed faster times than the maximum and average values proposed in PASm-12, with the exception of the final competition, where performance was slightly lower due to external competitive factors (Cohen's d = -0.53, t = -1.192, p = 0.3). This plan, demonstrating good practice, could serve as a guideline model for amateur runners who do not have specialist counseling. PASm-12 can reduce the risk of injury, prevent excessive fatigue, and support ongoing participation in sports activities. Additionally, the implementation of this plan could provide amateur runners with a safe and effective training structure, contributing to improved health and athletic performance.

Effects of High-Intensity Interval Training on the Parameters Related to Physical Fitness and Health of Older Adults: A Systematic Review and Meta-Analysis

BACKGROUND

As a novel and time-efficient exercise form, high-intensity interval training (HIIT) has shown great potential in improving health-related physical fitness among diverse populations. However, empirical evidence on its efficacy among the elderly has not been well summarized. This systematic review and meta-analysis aimed to determine the effect of HIIT interventions on the parameters related to physical fitness and health of older adults, including resting heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), cardiorespiratory fitness (CRF), body mass index (BMI), body fat percent (BF%), waist circumference (WC), muscular endurance (ME), muscular strength (MS), muscular power (MP), balance and flexibility, compared to non-exercise and other-exercise (e.g., moderate-intensity continuous training, resistance training) conditions.

METHODS

Literature published from January 2000 to May 2023 was collected through extensive searches across eight databases and relevant review papers. Randomized controlled trials (RCTs) featuring a minimum 2-week exercise intervention for older adults (≥ 60 years) were included. The pooled effect size of Hedges'g was estimated using random-effects models in R. Meta-regression was performed for both categorical (health status, duration of training programme, and frequency) and continuous moderators (mean age, male rate, and attrition rate).

RESULTS

Forty-four eligible RCTs with 1863 participants (52.1% female; 60.5-81.2 years) were included in the quantitative analysis. Compared to non-exercise condition, HIIT significantly improved resting HR (g = -0.36, 95%CI = [-0.67, -0.05], P = 0.032), SBP (g = -0.29, 95%CI = [-0.54, -0.03], P = 0.008), CRF (g = 0.77, 95%CI = [0.51, 1.04], P < 0.001), BF% (g = -0.26, 95%CI = [-0.41, -0.11], P = 0.006), MS (g = 0.47, 95%CI = [0.23, 0.71], P = 0.004), ME (g = 0.65, 95%CI = [0.10, 1.19], P = 0.036), and balance (e.g., timed-up-and-go) (g = -0.79, 95%CI = [-1.19, -0.40], P = 0.035). Compared to other-exercise condition, HIIT significantly improved resting HR (g = -0.11, 95%CI = [-0.21, -0.01], P = 0.029), SBP (g = -0.14, 95%CI = [-0.28, -0.01], P = 0.038), and CRF (g = 0.23, 95%CI = [0.07, 0.38], P = 0.008). No significant difference was found between HIIT and non-exercise condition for DBP, BMI and WC, as well as between HIIT and other-exercise condition for DBP, BMI, BF%, WC, ME, and balance (all P > 0.05). Meta-regression indicated that mean age moderated the HIIT effect on resting HR (b = -0.02, P = 0.014; HIIT vs. other-exercise condition) and SBP (b = 0.03, P = 0.048; HIIT vs. non-exercise), and attrition rate moderated the effect on CRF (b = 0.03, P = 0.007; HIIT vs. non-exercise).

CONCLUSION

This study supports the efficacy of HIIT in improving resting HR, SBP, CRF, BF%, MS, ME and balance among older adults. More empirical evidence is needed to determine the efficacy of HIIT for MP and flexibility in this population.

TRIAL REGISTRATION

PROSPERO CRD42022316246.

Assessing physical fitness adaptations in collegiate male soccer players through training load parameters: a two-arm randomized study on combined small-sided games and running-based high-intensity interval training

Objective

To evaluate the effects of a 4-week intervention combining small-sided games (SSGs) and high-intensity interval training (HIIT) on physical fitness in collegiate male soccer players.

Methods

Twenty-one soccer players were randomly assigned to either the HIIT + SSGs group (n = 11) or a control group (n = 10). Physical fitness was assessed at baseline and 1-week post-intervention, including countermovement jump (CMJ), change of direction (COD) test, sprint test, repeated sprint ability (RSA) test, and 30-15 Intermittent Fitness Test (30-15IFT). The intervention comprised eight sessions over 4 weeks: four SSGs and four HIIT.

Results

The intervention group showed small to moderate improvements: mean RSA improved by 4.5% (p = 0.07), CMJ increased by 3.2% (p = 0.12), and 30-15IFT scores enhanced by 6.8% (p = 0.09). Key predictors of group membership included heart rate load per minute (OR 1.602) and various GPS variables.

Conclusion

The 4-week intervention combining SSGs with HIIT did not produce statistically significant improvements in most physical fitness variables compared to the control group. Although there were positive trends in variables such as RSA and 30-15IFT, these changes were modest and not statistically significant. The results suggest that while the combined SSGs and HIIT approach shows potential, its impact on physical fitness over a 4-week period is limited, with some variables, like CMJ, even showing decreases.

Cardiorespiratory fitness, atrial fibrillation and stroke: a review of the evidence in 2024

INTRODUCTION

The body of evidence linking cardiorespiratory fitness (CRF) levels with the risk of atrial fibrillation (AF) and stroke - two interconnected cardiovascular conditions - is not entirely consistent. Furthermore, specific CRF thresholds beyond which the risk of AF or stroke might not decrease are not well defined.

AREAS COVERED

This review summarizes research evidence on the role of CRF in the development of AF and stroke including dose-response relationships in general population participants, explores the biological mechanisms through which CRF may exert its effects, assesses the potential implications for clinical care and population health, identifies gaps in the current evidence, and suggest directions for future research. MEDLINE and Embase were searched from inception until July 2024 to identify observational longitudinal and interventional studies as well as systematic reviews and meta-analyses related to these study designs.

EXPERT OPINION

In the general population, increasing levels of CRF, achieved through consistent physical activity, can significantly reduce the likelihood of developing AF and stroke. The findings also advocate for a tailored approach to exercise prescriptions, acknowledging the plateau in benefits for AF risk beyond certain CRF levels, while advocating for higher intensity or prolonged activity to further reduce stroke risk.

Intensity and Pace Calculation of Ultra Short Race Pace Training (USRPT) in Swimming-Take-Home Messages and Statements for Swimming Coaches

A recently referenced method known as ultra short race pace training (USRPT), designed to familiarize swimmers with the pace of a swimming event by using high volumes and submaximal intensities, has emerged as an efficient approach, enhancing performance and predicting swimming outcomes. Despite its recognized benefits, particularly its lower physiological burden compared to other training methods, research on USRPT is still in its early stages. There are misunderstandings related to its intensity and the pace of calculation. This systematic review aims to provide valid statements identifying the pros and cons of USRPT as a training stimulus and providing swimming coaches with key messages and advice about this training method. For the analysis, 90,612 studies from PubMed, EBSCO, Science Direct, and Google Scholar databases were screened to research the background, intensity, and pace calculation of the USRPT method, although only four met the inclusion criteria. The final screening of the selected studies was conducted using a PRISMA-P document. USRPT has the potential to become a dominant training stimulus, offering a precise alternative to the often vague training sets that many swimmers use. However, further studies focusing on specific aspects of intensity and pace calculation within USRPT sets are needed for comprehensive understanding. In conclusion, USRPT appears to be a submaximal variation of high-intensity interval training (HIIT) with low blood lactate relevance to swimming events. Also, the pace calculation must be implemented considering the different demands of each point of a swimming event.