Purpose: To determine if: (i) mean power output and enjoyment of high‐intensity interval training (HIIT) are enhanced by virtual‐reality (VR)‐exergaming (track mode) compared to standard ergometry (blank mode), (ii) if mean power output of HIIT can be increased by allowing participants to race against their own performance (ghost mode) or by increasing the resistance (hard mode), without compromising exercise enjoyment.Methods: Sixteen participants (8 males, 8 females, VO₂max: 41.2 ± 10.8 ml⁻¹·kg⁻¹·min⁻¹) completed four VR‐HIIT conditions in a partially‐randomised cross‐over study; (1a) blank, (1b) track, (2a) ghost, and (2b) hard. VR‐HIIT sessions consisted of eight 60 s high‐intensity intervals at a resistance equivalent to 70% (77% for hard) maximum power output (P_MAX), interspersed by 60 s recovery intervals at 12.5% P_MAX, at a self‐selected cadence. Expired gases were collected and VO₂ measured continuously. Post‐exercise questionnaires were administered to identify differences in indices related to intrinsic motivation, subjective vitality, and future exercise intentions.Results: Enjoyment was higher for track vs. blank (difference: 0.9; 95% CI: 0.6, 1.3) with no other differences between conditions. There was no difference in mean power output for track vs. blank, however it was higher for track vs. ghost (difference: 5 Watts; CI: 3, 7), and hard vs. ghost (difference: 19 Watts; 95% CI: 15, 23).Conclusions: These findings demonstrate that VR‐exergaming is an effective intervention to increase enjoyment during a single bout of HIIT in untrained individuals. The presence of a ghost may be an effective method to increase exercise intensity of VR‐HIIT.

Objectives: This systematic review with meta-analysis compared cardiometabolic syndrome (CMS) in adults with chronic (≥1 year) spinal cord injury (SCI) to non-SCI individuals (controls) and athletes, analyzing the effect of specific injury characteristics and exploring temporal and geographical trends. Methods: Ovid Medline, Embase, Cochrane, CINAHL, Scopus, and Web of Science were searched from inception to September 2024. Adults with chronic SCI were included based on observational and baseline data derived from experimental studies. Quality Assessment Criteria for Evaluating Primary Research Papers from a Variety of Fields assessed quality. Weighted means with 95% bootstrapped confidence intervals (CI) were computed for risk stratification. Group differences were assessed using random effects meta-analysis, calculating weighted mean differences with 95% bootstrapped CI. Temporal and geographical trends were evaluated with linear regression based on sample-size-weighted distributions and relevant covariates. Results: Of 31,163 identified records, 471 studies were included (n ≤ 31,782 SCI participants). CMS was present in men with SCI, paraplegia, tetraplegia, and injuries above T6; men with complete SCI (AIS A); and men and women with motor-complete SCI (AIS A–B). Compared to controls, adults with SCI had a lower body mass index (BMI), higher total and visceral fat, and worse lipid and carbohydrate profiles, including increased insulin resistance (IR). Tetraplegia was associated with greater visceral fat, poorer glycemic control, and lower BMI, insulin sensitivity, high-density lipoprotein-cholesterol (HDL-C), and triglycerides than paraplegia. Motor-complete SCI had lower BMI, HDL-C, and fasting glucose than motor-incomplete injuries. Injuries above T6 had lower blood pressure and higher fasting insulin levels than those below T6. Athletes with SCI had a lower BMI, fat mass, and fasting glucose, and higher systolic blood pressure than non-athletes with SCI, but frequently presented with obesity and carbohydrate dysfunction. Temporal analysis revealed increasing obesity trends and improved systolic blood pressure, while other CMS risk factors remained unchanged. We also identified global variations in obesity, lipids, blood pressure, and carbohydrate patterns. Conclusions: With a large sample, we revealed a widespread cardiometabolic burden in chronic SCI, even among athletes. Specifically, obesity, IR, and hypoalphalipoproteinemia worsened with increasing injury severity, alongside rising obesity trends and geographic disparities in risk profiles. These patterns highlight the evolution of what was deemed an epidemic into a global cardiometabolic pandemic.

Maintaining healthy myofiber type and metabolic function early after spinal cord injury (SCI) may prevent chronic metabolic disorders. This study compares the effects of a 2–5 week combined (aerobic + resistance) neuromuscular electrical stimulation (Comb-NMES) regimen versus a sham control treatment on muscle protein signaling for glucose uptake, myofiber type distribution, and metabolic function. Twenty participants (31 ± 9 years of age) with an SCI (C4-L1, AIS level A–C) within 14 days of the SCI were randomly assigned to control (N = 8) or Comb-NMES (N = 12). Sessions were given three times per week. Fasting blood samples and vastus lateralis muscle biopsies were collected 24–48 h before or after the last session. Western blots were performed to quantify proteins, immunohistochemical analyses determined muscle myofiber distribution, and enzymatic assays were performed to measure serum glucose, insulin, and lipids. Our main findings include a decrease in fasting glucose (p < 0.05) and LDL-C (p < 0.05) levels, an upregulation of CamKII and Hexokinase (p < 0.05), and an increase in type I (+9%) and a decrease in type IIx (−36%) myofiber distribution in response to Comb-NMES. Our findings suggest that maintaining healthy myofiber type and metabolic function may be achieved via early utilization of Comb-NMES.

In individuals with a spinal cord injury (SCI), rapid skeletal muscle atrophy and metabolic dysfunction pose profound rehabilitation challenges, often resulting in substantial loss of muscle mass and function. This study evaluates the effect of combined neuromuscular electrical stimulation (Comb-NMES) on skeletal muscle cross-sectional area (CSA) and inflammatory signaling within the acute phase of SCI. We applied a novel Comb-NMES regimen, integrating both high-frequency resistance and low-frequency aerobic protocols on the vastus lateralis muscle, to participants early post-SCI. Muscle biopsies were analyzed for CSA and inflammatory markers pre- and post-intervention. The results suggest a potential preservation of muscle CSA in the Comb-NMES group compared to a control group. Inflammatory signaling proteins such as TLR4 and Atrogin-1 were downregulated, whereas markers associated with muscle repair and growth were modulated beneficially in the Comb-NMES group. The study’s findings suggest that early application of Comb-NMES post-SCI may attenuate inflammatory pathways linked to muscle atrophy and promote muscle repair. However, the small sample size and variability in injury characteristics emphasize the need for further research to corroborate these results across a more diverse and extensive SCI population.

Study design: Secondary analysis of a randomized, multi-center, placebo-controlled study(Sygen®). Objectives: To evaluate racial differences in serological markers in individuals with spinal cord injury(SCI) across the first year of injury. Setting: Hospitals in North America. Methods: Serological markers (e.g.,cell count, liver, kidney, and pancreatic function, metabolism, and muscle damage) were assessed among 316 participants (247 White, 69 Black) at admission, weeks 1, 2, 4, 8, and 52 post-injury. Linear mixed models were employed to explore the main effects of time, race (Black vs. White), and their interaction, with adjustment of covariates such as study center, polytrauma, injury (level, completeness), treatment group, and sex. Results: A main effect of race was observed where White individuals had higher alanine transaminase, blood urea nitrogen(BUN), BUN/Creatinine ratio, sodium, and chloride, while Black individuals had higher calcium, total serum protein, and platelets. For markers with interaction effects, post-hoc comparisons showed that at week 52, White individuals had higher mature neutrophils, hematocrit, hemoglobin, mean corpuscular hemoglobin, albumin, and triglycerides, and Black individuals had higher amylase. Eosinophils, monocytes, red blood cells, aspartate aminotransferase, bilirubin, cholesterol, partial thromboplastin time, urine specific gravity, urine pH, CO2, and inorganic phosphorus did not differ between races. Conclusions: Our results revealed racial differences in serological markers and underscores the importance of considering race as a determinant of physiological responses. Future studies are warranted to explore the causes and implications of these racial disparities to facilitate tailored clinical management and social policy changes that can improve health equity.