Background/Objectives: Parkinson’s disease (PD) is a progressive neurodegenerative disorder characterized by motor symptoms such as tremor, bradykinesia, rigidity, and postural instability. In the absence of disease-modifying therapies, exercise remains one of the few interventions shown to effectively reduce fall risk and improve mobility. However, it remains unclear whether skeletal muscle ATP metabolism is impaired in PD, and whether the benefits of exercise arise primarily from improvements in central motor control or peripheral metabolic adaptations. Methods: Fourteen individuals with PD and five healthy controls underwent kinetic ³¹P Magnetic Resonance Spectroscopy (MRS) to assess resting muscle ATP synthesis and dynamic ³¹P MRS during in-magnet exercise to evaluate oxidative phosphorylation in active muscle. Results: At rest, ATP synthesis rates mediated by ATPase and creatine kinase (CK) were on average 46 ± 23% and 24 ± 9% lower, respectively, in the PD group compared to controls (p < 0.005), suggesting peripheral mitochondrial dysfunction. During plantar flexion exercise at 15% of lean body mass, range of motion (ROM) was reduced by 22 ± 5% in PD participants (p = 0.01). Despite this, post-exercise recovery of phosphocreatine (PCr) and inorganic phosphate (Pi) was similar between groups. Recovery time constants for PCr and Pi correlated with participants’ total weekly exercise time, indicating a metabolic adaptation to regular physical activity. Modest ROM improvements were observed in both groups following calf-raise exercise training. Conclusions: Reduced skeletal muscle ATP metabolism may contribute to peripheral weakness in PD. Regular exercise appears to promote adaptive metabolic responses, highlighting the need for therapeutic strategies targeting both central and peripheral components of PD.

Purpose: The prevalence of individuals with obesity classes 4 and 5 is increasing, with no optimal surgical approach identified. With the rising popularity of one anastomosis gastric bypass (OAGB), we conducted a single-arm meta-analysis to assess its outcomes in this population. Materials and Methods: A comprehensive search of PubMed, Scopus, EMBASE, and Cochrane identified studies on OAGB reporting weight loss, comorbidity remission, and complications. Statistical analysis was performed using RStudio 4.4.1. Heterogeneity was assessed using the Cochrane Q test and I 2 statistics. Results: Seventeen studies including 2,274 patients (mean age, 40.44 years), were identified. The analysis revealed a rising trend up to 24 months, with a pooled excess weight loss (%) of 68.08% (95% confidence interval [CI], 63.64-72.52; I 2 =95.6%), and total weight loss (%) of 36.63% (95% CI, 35.34-37.92; I 2 =84.6%) at 12 months. Diabetes and hypertension remission rates were 82.02% (95% CI, 70.36-89.77; I 2 =59.5%) and 78.06% (95% CI, 59.05-89.77; I 2 =84.9%), respectively. The incidence of de novo gastroesophageal reflux disease was 4.38% (95% CI, 0.61-25.59; I 2 =91.9%). Conclusion: OAGB can be a valuable option for this population, awaiting long-term data.

Background/Objectives: Dynamic changes in inorganic phosphate (Pi), phosphocreatine (PCr), and pH during post-exercise recovery reflect underlying muscle energetics and mitochondrial ATP synthesis, but the conventional single-pool model assuming uniform metabolic response fails to address myofiber composition and pH-dependent metabolic heterogeneity in skeletal muscle. This study aimed to characterize the interplay between pH, Pi, and PCr, and to develop an analytical method for assessing pH-resolved ATP synthesis using ³¹P MRS. Methods: Five healthy subjects underwent dynamic ³¹P MRS scans during plantar flexion exercise. ATP synthesis was evaluated from post-exercise PCr and Pi recovery time courses using the single-pool model, and from Pi recovery time courses using a multi-pool model in which the Pi signal lineshape was segmented into four pH-specific pools: alkaline (pH 7.3 ± 0.2), neutral (pH 7.0 ± 0.1), mildly acidic (pH 6.8 ± 0.1), and moderately acidic (pH 6.6 ± 0.1). Results: The single-pool model showed that during exercise, Pi increased proportionally to PCr depletion, and both Pi and PCr recovered monoexponentially immediately after exercise with ${\tau }_{\mathrm{Pi}} \left(33\pm 9 \mathrm{s}\right)<{\tau }_{\mathrm{PCr}} (40 \pm 9 \mathrm{s})$; ATP remained stable while pH exhibited a “heart-beat” pattern, characterized by an initial alkalization followed by neutralization during exercise, a post-exercise acidic undershoot, and a subsequent slow recovery (${\tau }_{\mathrm{pH}}\gg {\tau }_{\mathrm{PCr}}$). The four-pool model demonstrated a pronounced pH dependence of Pi recovery, with slower recovery at lower pH (${\tau }_{\mathrm{Pi}}$: 19 ± 6 s at pH 7.3, 25 ± 7 s at pH 7.0, 32 ± 11 s at pH 6.8, and 46 ± 17 s at pH 6.6). Pi recovery is slowed with aging under acidic conditions, with little or no effect observed at neutral or alkaline pH. These results provide new insights into skeletal muscle metabolic heterogeneity, reflecting how different myofiber microenvironments modulate ATP synthesis. Conclusions: By overcoming the constraints of the single-pool model, the proposed multi-pool framework uncovers pH-dependent ATP synthesis and provides direct evidence of pronounced metabolic heterogeneity in skeletal muscle during exercise and recovery.