17 research outputs found
Comparison of Cardiorespiratory and Metabolic Responses Between Kettlebell Half Marathon and Treadmill Running at the Same Average Oxygen Consumption: A Case Study
No full textPurposesIn kettlebell sport (KS) half marathon, the lift of the kettlebell is required for the highest number of repetitions in 30 min. No data are available on cardiorespiratory and metabolic responses during this exercise routine. The aim of the study was to evaluate cardiopulmonary and metabolic responses to KS half marathon compared to 30 min treadmill running, chosen as a reference paradigm of aerobic exercise, at the same average oxygen consumption (VO2).MethodsA male elite KS athlete was enrolled in two trials separated by 7 days of rest. In the first trial, one-hand long-cycle KS exercise with a 1/3 body weight kettlebell was performed for 30 min (kettlebell half marathon, KT); in the second trial, 30 min treadmill running (TR) was performed at the same average VO2 measured in the first trial (speed 9-10 km/h at 1 degrees uphill inclination). Metabolic and cardiopulmonary assessments [respiratory exchange ratio (RER), tidal volume (TV), breathing frequency (f), minute ventilation (VE)], blood lactate (BL) kinetics, heart rate (HR), and blood pressure (BP) were measured in both experimental sessions.ResultsThe average VO2 was 33.3 mL/min/kg in KT and 30.6 mL/min/kg in TR. The subject achieved RERpeak 1.17, RERmean 0.98, HRpeak 172 bpm (94% HRmax), HRmean 86% of HRmax, BPpeak 220/100 mmHg in KT, BLpeak 7.2 mmol/L (during trial) in KT and RERpeak 1.13, RERmean 0.89, HRpeak 142 bpm (78% HRmax), HRmean 70% of HRmax, BPpeak 160/80 mmHg, BLpeak 3.5 mmol/L (4 min after trial) mmol/L in TR.ConclusionData indicate that a KS half marathon determines much higher cardiopulmonary and metabolic responses to treadmill running performed at similar VO2
Nutrition and Exercise in a Case of Carnitine Palmitoyl-Transferase II Deficiency
No full textIn the mild subtype of inherited carnitine palmitoyltransferase II (CPTII) deficiency, muscular mitochondrial fatty acid beta-oxidation is impaired. In this condition, interventions involve daily dietary restriction of fats and increase of carbohydrates, whereas physical exercise is commonly contraindicated due to the risk of muscle pain and rhabdomyolysis. We present the case of a 14-year-old female with CPTII deficiency who underwent a 1-h session of unsupervised exercise training for 6 months, 3 days per week, including interval and resistance exercises, after diet assessment and correction. Before and after intervention, the resting metabolic rate (RMR) and respiratory quotient (RQ) were measured by indirect calorimetry, and a cardiopulmonary exercise test (CPET, 10 W/30 s to exhaustion) was performed. Interval training consisted of a 1 min run and a 5 min walk (for 15 min progressively increased to 30 min). During these efforts, the heart rate was maintained over 70% HR max corresponding to respiratory exchange ratio (RER) of 0.98. Resistance training included upper/lower split workouts (3 sets of 8 repetitions each, with 2 min rest between sets). Blood CK was checked before and 36 h after two training sessions chosen randomly without significant difference. After training, RMR increased (+8.1%) and RQ lowered into the physiological range (from 1.0 to 0.85). CPET highlighted an increase of peak power output (+16.7%), aerobic performance (VO2 peak, 8.3%) and anaerobic threshold (+5.7%), oxygen pulse (+4.5%) and a much longer isocapnic buffering duration (+335%). No muscle pain or rhabdomyolysis was reported. Results from our study highlight that training based on short-duration high-intensity exercise improves overall metabolism and aerobic fitness, thus being feasible, at least in a case of CPTII deficiency
Rifaximin modulates the vaginal microbiome and metabolome in women affected by bacterial vaginosis
No full textAbstract: Bacterial vaginosis (BV) is a common vaginal disorder characterized by the decrease of lactobacilli and overgrowth of Gardnerella vaginalis and resident anaerobic vaginal bacteria. In the present work, the effects of rifaximin vaginal tablets on vaginal microbiota and metabolome of women affected by BV were investigated by combining quantitative PCR and a metabolomic approach based on H-1 nuclear magnetic resonance. To highlight the general trends of the bacterial communities and metabolomic profiles in response to the antibiotic/placebo therapy, a multivariate statistical strategy was set up based on the trajectories traced by vaginal samples in a principal component analysis space. Our data demonstrated the efficacy of rifaximin in restoring a health-like condition in terms of both bacterial communities and metabolomic features. In particular, rifaximin treatment was significantly associated with an increase in the lactobacillus/BV-related bacteria ratio, as well as with an increase in lactic acid concentration and a decrease of a pool of metabolites typically produced by BV-related bacteria (acetic acid, succinate, shortchain fatty acids, and biogenic amines). Among the tested dosages of rifaximin (100 and 25 mg for 5 days and 100 mg for 2 days), 25 mg for 5 days was found to be the most effective
Cutaneous metastasis from vulvar squamous cell carcinoma: a rare occurrence that should not be forgotten
No full textVulvar cancer accounts for 5% of the female genital tract cancers. Cutaneous metastases from vulvar cancer are extremely rare and for this reason, it can be difficult to reach a diagnosis with a consequent delay in the treatment. A systematic literature review of articles on this subject was conducted through a MEDLINE-based search for articles published in English or French. To date, 16 cases (including ours unpublished) of cutaneous metastasis from vulvar cancer have been reported. Cutaneous metastasis can occur from any stage of vulvar cancer, even after a short period. Different treatments have been described but none of them seems to be more effective. In all reported cases the prognosis was very poor. Every time a vulvar cancer survivor shows a suspicious cutaneous lesion, this should be biopsied to exclude skin relapse. Impact statement Cutaneous metastases from vulvar cancer are extremely rare and due to its rarity, a standard treatment has not been established yet. Cutaneous metastasis can occur from any stage of vulvar cancer, even after a short period. In all the reported cases, the prognosis was very poor. Every time a vulvar cancer survivor shows a suspect cutaneous lesion, this should be biopsied to exclude skin relapse
Muscle Fiber Conduction Velocity Correlates With the Age at Onset in Mild FSHD Cases
No full textA majority of patients with facioscapulohumeral muscular dystrophy (FSHD) report severe fatigue. The aim of this study was to explore whether fatigability during a performance task is related to the main clinical features of the disease in mildly affected patients. A total of 19 individuals with a molecular genetic-based diagnosis of FSHD (median D4Z4 deletion length of 27 kb) performed two isometric flexions of the dominant biceps brachii at 20% of their maximal voluntary contraction (MVC) for 2 min, and then at 60% MVC until exhaustion. Fatigability indices (average rectified value, mean frequency, conduction velocity, and fractal dimension) were extracted from the surface electromyogram (sEMG) signal, and their correlations with age, age at onset, disease duration, D4Z4 contraction length, perceived fatigability, and clinical disability score were analyzed. The conduction velocity during the low level contraction showed a significant negative correlation with the age at onset (p < 0.05). This finding suggest the assessment of conduction velocity at low isometric contraction intensities, as a potential useful tool to highlight differences in muscle involvement in FSHD patients
Increased resistance towards fatigability in patients with facioscapulohumeral muscular dystrophy
No full textPurpose In facioscapulohumeral muscular dystrophy (FSHD) fatigue is a major complaint. We aimed to investigate whether during isometric sustained elbow flexions, performance fatigability indexes differ in patients with FSHD with respect to healthy controls. Methods Seventeen patients with FSHD and seventeen healthy controls performed two isometric flexions of the dominant biceps brachii at 20% of their maximal voluntary contraction (MVC) for 2 min and then at 60% MVC until exhaustion. Muscle weakness was characterized as a percentage of predicted values. Maximal voluntary strength, endurance time and performance fatigability indices (mean frequency of the power spectrum (MNF), muscle fiber conduction velocity (CV) and fractal dimension (FD)), extracted from the surface electromyogram signal (sEMG) were compared between the two groups. Results In patients with FSHD, maximal voluntary strength was 68.7% of predicted value (p < 0.01). Compared to healthy controls, FSHD patients showed reduced MVC (p < 0.001; r = 0.62) and lower levels of performance fatigability, characterized by reduced rate of changes in MNF (p < 0.01; r = 0.56), CV (p < 0.05; 0.37) and FD (p < 0.001; r = 0.51) and increased endurance time (p < 0.001; r = 0.63), during the isometric contraction at 60% MVC. Conclusion A decreased reduction in the slopes of all the considered sEMG parameters during sustained isometric elbow flexions suggests that patients with FSHD experience lower levels of performance fatigability compared to healthy controls
Motor unit synchronization and firing rate correlate with the fractal dimension of the surface EMG: A validation study
No full textThe fractal dimension (FD) of the surface electromyographic (EMG) signal has been reported to be influenced by changes in the firing rate and synchronization of motor units. The purpose of this study was to validate these relations during experimental signals.Thirteen healthy subjects (12 men and 1 woman) performed an isometric knee extension at 5 % of their maximal voluntary contraction for 300 s. Intramuscular and surface EMG signal were recorded concurrently from the vastus medialis obliquus. Synchronization and firing rate were calculated from the decomposed intramuscular EMG signal, while FD was estimated using the box-counting method. The first and last 50 s of contractions were considered during the correlation analyses.FD was negatively related to the level of motor unit synchronization (rs = -0.30; p < 0.05) and positively correlated with firing rate (rs = 0.25; p < 0.01) when all data were pooled. FD was correlated with firing rate only during the initial 50 s of contraction (rs = 0.52; p < 0.001).FD of the sEMG signal is a parameter mostly related to the firing rate when fatigue does not develop and may be considered as an index of performance fatigability during sustained or at the end of prolonged contractions at very low forces. Indeed, FD cannot be considered as an exclusive index of motor unit synchronization during fatiguing contractions, but rather as largely related to central factors
Inter-Gender sEMG Evaluation of Central and Peripheral Fatigue in Biceps Brachii of Young Healthy Subjects
No full textThe purpose of the present study was to evaluate inter-arm and inter-gender differences in fractal dimension (FD) and conduction velocity (CV) obtained from multichannel surface electromyographic (sEMG) recordings during sustained fatiguing contractions of the biceps brachii.A total of 20 recreationally active males (24±6 years) and 18 recreationally active females (22±9 years) performed two isometric contractions at 120 degrees elbow joint angle: (1) at 20% maximal voluntary contraction (MVC) for 90 s, and (2) at 60% MVC until exhaustion the time to perform the task has been measured. Signals from sEMG were detected from the biceps brachii using bidimensional arrays of 64 electrodes and initial values and rate of change of CV and FD of the sEMG signal were calculated.) of CV and FD slopes was found between genders (p>0.05). During the sustained 60% MVC no statistical correlation was found between MVC and CV or FD initial estimates nor between MVC and CV or FD slopes both in males and females whereas. A significant positive correlation between CV and FD slopes was found in both genders (males: r = 0,61; females: r = 0,55).Fatigue determines changes in FD and CV values in biceps brachii during sustained contractions at 60% MVC. In particular males show greater increase in the rate of change of CV and FD than females whereas no difference in percentage change of these sEMG descriptors of fatigue was found. A significant correlation between FD and CV slopes found in both genders highlights that central and peripheral myoelectric components of fatigue may interact during submaximal isometric contractions
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Rifaximin modulates the colonic microbiota of patients with Crohn's disease: an in vitro approach using a continuous culture colonic model system.
No full textRifaximin, a rifamycin derivative, has been reported to induce clinical remission of active Crohn's disease (CD), a chronic inflammatory bowel disorder. In order to understand how rifaximin affects the colonic microbiota and its metabolism, an in vitro human colonic model system was used in this study. We investigated the impact of the administration of 1800 mg/day of rifaximin on the faecal microbiota of four patients affected by colonic active CD [Crohn's disease activity index (CDAI > 200)] using a continuous culture colonic model system. We studied the effect of rifaximin on the human gut microbiota using fluorescence in situ hybridization, quantitative PCR and PCR–denaturing gradient gel electrophoresis. Furthermore, we investigated the effect of the antibiotic on microbial metabolic profiles, using 1H-NMR and solid phase microextraction coupled with gas chromatography/mass spectrometry, and its potential genotoxicity and cytotoxicity, using Comet and growth curve assays. Rifaximin did not affect the overall composition of the gut microbiota, whereas it caused an increase in concentration of Bifidobacterium, Atopobium and Faecalibacterium prausnitzii. A shift in microbial metabolism was observed, as shown by increases in short-chain fatty acids, propanol, decanol, nonanone and aromatic organic compounds, and decreases in ethanol, methanol and glutamate. No genotoxicity or cytotoxicity was attributed to rifaximin, and conversely rifaximin was shown to have a chemopreventive role by protecting against hydrogen peroxide-induced DNA damage. We demonstrated that rifaximin, while not altering the overall structure of the human colonic microbiota, increased bifidobacteria and led to variation of metabolic profiles associated with potential beneficial effects on the host
