The present study aimed to determine the effect of high intensity interval training (HIIT) in hypoxia on maximal oxygen uptake (VO_2max) compared with HIIT in normoxia with a Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA)-accordant meta-analysis and meta-regression. Studies which measured VO_2max following a minimum of 2 weeks intervention featuring HIIT in hypoxia versus HIIT in normoxia were included. From 119 originally identified titles, nine studies were included (n = 194 participants). Meta-analysis was conducted on change in (∆) VO_2max using standardised mean difference (SMD) and a random effects model. Meta-regression examined the relationship between the extent of environmental hypoxia (fractional inspired oxygen [FiO₂]) and ∆VO_2max and intervention duration and ∆VO_2max. The overall SMD for ∆VO_2max following HIIT in hypoxia was 1.14 (95% CI = 0.56–1.72; p < 0.001). Meta-regressions identified no significant relationship between FiO₂ (coefficient estimate = 0.074, p = 0.852) or intervention duration (coefficient estimate = 0.071, p = 0.423) and ∆VO_2max. In conclusion, HIIT in hypoxia improved VO_2max compared to HIIT in normoxia. Neither extent of hypoxia, nor training duration modified this effect, however the range in FiO₂ was small, which limits interpretation of this meta-regression. Moreover, training duration is not the only training variable known to influence ∆VO_2max, and does not appropriately capture total training stress or load. This meta-analysis provides pooled evidence that HIIT in hypoxia may be more efficacious at improving VO_2max than HIIT in normoxia. The application of these data suggest adding a hypoxic stimuli to a period of HIIT may be more effective at improving VO_2max than HIIT alone. Therefore, coaches and athletes with access to altitude (either natural or simulated) should consider implementing HIIT in hypoxia, rather than HIIT in normoxia where possible, assuming no negative side effects.

This study aimed to compare flow-mediated dilation values between individuals with Long COVID, Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS), and healthy age-matched controls to assess the potential implications for clinical management and long-term health outcomes. A case-case-control approach was employed, and flow-mediated dilation measurements were obtained from 51 participants (17 Long COVID patients, 17 ME/CFS patients, and 17 healthy age-matched controls). Flow-mediated dilation values were analysed using one-way ANOVA for between-group comparisons. Results revealed significantly impaired endothelial function in both Long COVID and ME/CFS groups compared to healthy age-matched controls as determined by maximum % brachial artery diameter post-occlusion compared to pre-occlusion resting diameter (6.99 ± 4.33% and 6.60 ± 3.48% vs. 11.30 ± 4.44%, respectively, both p < 0.05). Notably, there was no difference in flow-mediated dilation between Long COVID and ME/CFS groups (p = 0.949), despite significantly longer illness duration in the ME/CFS group (ME/CFS: 16 ± 11.15 years vs. Long COVID: 1.36 ± 0.51 years, p < 0.0001). The study demonstrates that both Long COVID and ME/CFS patients exhibit similarly impaired endothelial function, indicating potential vascular involvement in the pathogenesis of these post-viral illnesses. The significant reduction in flow-mediated dilation values suggests an increased cardiovascular risk in these populations, warranting careful monitoring and the development of targeted interventions to improve endothelial function and mitigate long-term health implications.

Breast cancer chemotherapy, although very potent against tumour tissue, results in significant cardiovascular toxicity. The focus of research in this area has been predominantly towards cardiotoxicity. There is limited evidence detailing the impact of such treatment on the vasculature despite its central importance within the cardiovascular system and resultant detrimental effects of damage and dysfunction. This review highlights the impact of chemotherapy for breast cancer on the vascular endothelium. We consider the most likely mechanisms of endothelial toxicity to be through direct damage and dysfunction of the endothelium. There are sharp consequences of these detrimental effects as they can lead to cardiovascular disease. However, there is potential for exercise to alleviate some of the vascular toxicity of chemotherapy, and the evidence for this is provided. The potential role of exercise in protecting against vascular toxicity is explained, highlighting the recent in-human and animal model exercise interventions. Lastly, the mediating mechanisms of exercise protection of endothelial health is discussed, focusing on the importance of exercise for endothelial health, function, repair, inflammation and hyperlipidaemia, angiogenesis, and vascular remodelling. These are all important counteracting measures against chemotherapy-induced toxicity and are discussed in detail.

Commonly reported symptoms of long-COVID may have different patterns of prevalence and presentation across different countries. While some limited data has been reported for the UK, national specificity for Scotland is less clear. We present a cross-sectional survey to examine the symptom prevalence, frequency and severity of long-COVID for people living with the condition in Scotland. An online survey was created in the English language and was available between 21^st April 2022 and 5^th August 2022. Participants were included if they were ≥18 years old, living in Scotland, and had self-diagnosed or confirmed Long-COVID; and excluded if they were hospitalised during their initial infection. Within this article we quantify symptom prevalence, frequency, severity, and duration. Participants (n=253) reported the most prevalent long-COVID symptoms to be post-exertional malaise (95%), fatigue/tiredness (85%), and cognitive impairment (68%). Fatigue/tiredness, problems with activities of daily living (ADL), and general pain were most frequently occurring, whilst sleep difficulties, problems with ADL, and nausea were the most severe. Scottish Index of Multiple Deprivation associated with symptom number, severity and frequency, while vaccine status, age, sex, and smoking status had limited or no association. These findings outline the challenges faced for those living with long COVID and highlight the need for longitudinal research to ascertain a better understanding of the condition and its longer-term societal impact.

Background/Objectives: Advancements in breast cancer therapeutics, such as anthracyclines, are improving cancer survival rates but can have side effects that limit their use. Cardiotoxicity, defined as damage to the heart caused by cancer therapeutics, is characterised by a significant reduction in left ventricular ejection fraction (LVEF) and symptoms of cardiac dysfunction. Multiple oral supplements exist with antioxidant and anti-inflammatory properties that have the potential to lower cardiotoxicity risk and ameliorate the complications associated with left ventricular dysfunction. In this review, we evaluate the current status of using nutritional interventions to modulate cardiotoxicity. Methods: We used specific keywords to search for articles that met our predetermined inclusion and exclusion criteria to review the evidence and provide insights for future research. Results: Seven studies were identified as eligible for this review: six focused on oral supplementation strategies in breast cancer patients undergoing chemotherapy, and one focused on nutritional counselling and adherence to the Mediterranean diet in breast cancer survivors’ post-treatment. There was a significantly attenuated reduction in LVEF in five studies that monitored cardiometabolic health, and there were significant improvements in blood serum levels of cardiac biomarkers across all studies. Conclusions: Current evidence suggests that appropriate nutritional interventions, alongside chemotherapy, can modulate the risk of cardiotoxic side effects. This highlights the potential of oral antioxidant supplementation and Mediterranean diet counselling to decrease tertiary cancer therapy costs associated with cardiovascular complications.

There has been some effort to map the prevalence, frequency, and severity of symptoms of long-COVID at local and national levels. However, what is frequently absent from such accounts is details of the impact the disease and its symptoms have had on those living with the condition. In this manuscript, we present details of impact to work, caring, and mental health gathered using a cross-sectional survey. Data were collected using an online survey which was available from 21^st April 2022 to 5^th August 2022. Included participants had either self-diagnosed or confirmed long-COVID, were living in Scotland, and were ≥18 years old. Hospitalisation during initial COVID-19 infection was an exclusion criterion. Participants were asked to report on the impact of their illness on everyday activities such as working, studying, or caring. They also completed an assessment of their current mood. People with long-COVID were often severely impacted in their ability to work and study. Severe impact on work and study were predicted by more severe and more frequent fatigue, more severe pain, and more severe cognitive impairment. Respondents' ability to care for child dependants was also associated with more severe and more frequent fatigue, as well as more severe cognitive impairments. More severe pain associated with greater impact on adult care. Negative mood correlated most strongly with frequency and severity of neurological symptoms, including lack of attention, loss of smell, impaired sense of smell, loss of taste, impaired sense of taste, and loss of appetite. Long-COVID has a significant impact on ability to work, study, and care for dependants. The severity of this impact is associated with specific symptom burden, including fatigue, pain, and cognitive impairment.